Association of acculturation with cardiac structure and function among Hispanics/Latinos: a cross-sectional analysis of the echocardiographic study of Latinos.

OBJECTIVE:Hispanics/Latinos, the largest immigrant population in the USA, undergo the process of acculturation and have a large burden of heart failure risk. Few studies have examined the association of acculturation on cardiac structure and function. DESIGN:Cross-sectional. SETTING:The Echocardiographic Study of Latinos. PARTICIPANTS:1818 Hispanic adult participants with baseline echocardiographic assessment and acculturation measured by the Short Acculturation Scale, nativity, age at immigration, length of US residence, generational status and language. PRIMARY AND SECONDARY OUTCOME MEASURES:Echocardiographic assessment of left atrial volume index (LAVI), left ventricular mass index (LVMI), early diastolic transmitral inflow and mitral annular velocities. RESULTS:The study population was predominantly Spanish-speaking and foreign-born with mean residence in the US of 22.7 years, mean age of 56.4 years; 50% had hypertension, 28% had diabetes and 44% had a body mass index &gt;30 kg/m2. Multivariable analyses demonstrated higher LAVI with increasing years of US residence. Foreign-born and first-generation participants had higher E/e' but lower LAVI and e' velocities compared with the second generation. Higher acculturation and income &gt;20K were associated with higher LVMI, LAVI and E/e' but lower e' velocities. Preferential Spanish-speakers with an income <20K had a higher E/e'. CONCLUSIONS:Acculturation was associated with abnormal cardiac structure and function, with some effect modification by socioeconomic status

Steady jets from radiatively efficient hard states in GRS 1915+105

Recent studies of different X-ray binaries (XRBs) have shown a clear correlation between the radio and X-ray emission. We present evidence of a close relationship found between the radio and X-ray emission at different epochs for GRS1915+105, using observations from the Ryle Telescope and Rossi X-ray Timing Explorer satellite. The strongest correlation was found during the hard state (also known as the `plateau' state), where a steady AU-scale jet is known to exist. Both the radio and X-ray emission were found to decay from the start of most plateau states, with the radio emission decaying faster. An empirical relationship of $S_{\rm{radio}}\propto S_{\rm{X-ray}}^{\xi}$ was then fitted to data taken only during the plateau state, resulting in a power-law index of $\xi\sim1.7\pm0.3$, which is significantly higher than in other black hole XRBs in a similar state. An advection-flow model was then fitted to this relationship and compared to the universal XRB relationship as described by Gallo et al. (2003). We conclude that either (I) the accretion disk in this source is radiatively efficient, even during the continuous outflow of a compact jet, which could also suggest a universal turn-over from radiatively inefficient to efficient for all stellar-mass black holes at a critical mass accretion rate ($\dot{m}_{\rm{c}}\approx10^{18.5}$ g/s); or (II) the X-rays in the plateau state are dominated by emission from the base of the jet and not the accretion disk (e.g. via inverse Compton scattering from the outflow).Comment: 9 pages, 7 figures, accepted in A&

The efficiency control in the building sector

La efectividad del control en el sector de la construcción, es la búsqueda de una solución a una de las problemáticas para muchas empresas que dedican sus actividades a ejecutar proyectos de obra, donde la documentación de la información se vuelve un conjunto de inconvenientes, debido a que mucha de la documentación son procesos oficinescos que no permiten la correcta ejecución de los proyectos. Esta problemática es la causante de una serie de inconvenientes en la medida que se van ejecutando los proyectos, donde lo común es encontrar personal desmotivado, información escaza, imprecisa, archivos descomunales, pérdida de identidad de la información y derroche del presupuesto. Mediante una encuesta dicotómica, enfocada a personas que dedican sus labores al desarrollo de obras de construcción en el país, con perfiles profesionales de diferentes ramas, se buscara saber su opinión basado en la experiencia que han tenido en sus proyectos, se analizan las respuestas y se llega a una conclusión basada además en la opinión de algunos expertos que han realizado artículos sobre el tema. Además, de realizar el análisis de cada una de las respuestas de los encuestados, se analizan los conceptos de efectividad que ayuden a entender con mayor precisión de lo que se expone en esta investigación.The effectiveness of control in the construction sector, is the search for a solution to one of the problems for many companies that dedicate their activities to implement construction projects, where the documentation of information becomes a set of inconveniences, because many of the documentation are office processes that do not allow the proper implementation of projects. This problem is the cause of a series of inconveniences as the projects are executed; where the typical thing is to find unmotivated personnel, scarce and imprecise information, huge files, loss of identity of the information and waste of the budget. By means of a dichotomous survey, focused on people who dedicate their work to the development of construction works in the country, with professional profiles of different branches, we seek to know their opinion based on the experience they have had in their projects, the answers are analyzed and a conclusion is reached based on the opinion of some experts who have written articles on the subject. In addition to the analysis of each of the answers of the respondents, the concepts of effectiveness are analyzed to help understand more precisely what is exposed in this research.Especializació

La capacitación y su nivel de impacto en el desempeño laboral de los auditores gubernamentales 2021

El objetivo general de este estudio fue determinar el alcance del impacto de la capacitación en el desempeño laboral de los auditores gubernamentales. La investigación fue de tipo aplicada, de enfoque cuantitativo y de nivel correlacional. Asimismo, en la muestra de estudio se consideró el criterio de muestreo probabilístico conformándose un total de treinta y seis auditores. La técnica empleada de recolección de datos fue la encuesta y como instrumento el cuestionario que tuvo veinticinco ítems, entre los cuales catorce correspondieron a la variable capacitación, mientras que, once a la variable desempeño laboral. Este instrumento fue validado a través del juicio de expertos y se determinó su confiabilidad mediante el Alpha de Cronbach. El resultado obtenido de la aplicación de la encuesta permitió determinar que sí existió un nivel de impacto positivo de la capacitación en el desempeño laboral de los auditores gubernamentales, de acuerdo a la correlación determinada por el Rho de Spearman que evidenció un 0,489 considerada correlación positiva moderada. En tal sentido, se concluyó que el nivel de impacto que la capacitación generó en el desempeño laboral de los auditores resultó siendo positiva y coadyuvó al fortalecimiento del conocimiento en materia de Control Gubernamental

A transient low-frequency QPO from the black hole binary GRS 1915+105

We present the results of the timing analysis of five Rossi X-ray Timing Explorer observations of the Black Hole Candidate GRS 1915+105 between 1996 September and 1997 December. The aim was to investigate the possible presence of a type-B quasi-periodic oscillation (QPO). Since in other systems this QPO is found to appear during spectral transitions from Hard to Soft states, we analyzed observations characterized by a fast and strong variability, in order to have a large number of transitions. In GRS 1915+105, transitions occur on very short time scales (~ sec): to single them out we averaged Power Density Spectra following the regular path covered by the source on a 3D Hardness-Hardness-Intensity Diagram. We identified both the type-C and the type-B quasi-periodic oscillations (QPOs): this is the first detection of a type-B QPO in GRS 1915+105. As the spectral transitions have been associated to the emission and collimation of relativistic radio-jets, their presence in the prototypical galactic jet source strengthens this connection.Comment: 13 pages, 9 figures, accepted for publication on MNRA

Models of the Compact Jet in GRS 1915+105

In this article, models are constructed of the compact jet in GRS 1915+105 during an epoch of optimal data capture. On April 02, 2003, the object was observed in the hard X-ray/soft gamma ray band (INTEGRAL), hard X-ray band (RXTE), near IR (ESO/New Technology Telescope) and the VLBA (8.3 GHz and 15 GHz). The source was in a so-called "high plateau state." The large radio flux provides high signal to noise ratios in the radio images. Thus, one can image the jet out to large distances ($> 10^{15}$ cm). This combined with the broadband coverage make this epoch the best suited for modeling the jet. The parametric method developed in the papers \cite{ghi85,ghi89,ghi96,sam97} that has been successfully utilized in the realm of extragalactic radio jets is implemented. The basic model is one where external inverse Compton (EIC) scattering of accretion disk photons by jet plasma provides the hard X-ray powerlaw. Unlike AGN jets, it is found that the radio jet must be highly stratified in the transverse direction in order to produce the observed surface brightness distribution in the radio images. Various jet models are considered. The jet power is $Q \approx 3-4 \times 10^{38}$ ergs/sec if the hard X-ray powerlaw luminosity is from EIC in the jet and $Q \approx 2 - 9 \times 10^{37}$ ergs/sec if the X-rays are emitted from the accretion disk corona. These estimates indicate that the jet power can be as high as 60% of the total X-ray luminosity.Comment: To appear in MNRA

Detailed Radio to Soft Gamma-ray Studies of the 2005 Outburst of the New X-ray Transient XTE J1818-245

XTE J1818-245 is an X-ray nova that experienced an outburst in 2005, first seen by the RXTE satellite. The source was observed simultaneously at various wavelengths up to soft gamma-rays with the INTEGRAL satellite, from 2005 February to September. X-ray novae are extreme systems that often harbor a black hole, and are known to emit throughout the electromagnetic spectrum when in outburst. We analyzed radio, (N)IR, optical, X-ray and soft gamma-ray observations and constructed simultaneous broad-band X-ray spectra. Analyzing both the light curves in various energy ranges and the hardness-intensity diagram enabled us to study the long-term behavior of the source. Spectral parameters were typical of the Soft Intermediate States and the High Soft States of a black hole candidate. The source showed relatively small spectral variations in X-rays with considerable flux variation in radio. Spectral studies showed that the accretion disc cooled down from 0.64 to 0.27 keV in 100 days and that the total flux decreased while the relative flux of the hot medium increased. Radio emission was detected several times, and, interestingly, five days after entering the HSS. Modeling the spectral energy distribution from the radio to the soft gamma-rays reveals that the radio flares arise from several ejection events. XTE J1818-245 is likely a black hole candidate transient source that might be closer than the Galactic Bulge. The results from the data analysis trace the physical changes that took place in the system at a maximum bolometric luminosity of (0.4-0.9)e38 erg/s (assuming a distance between 2.8-4.3 kpc) and they are discussed within the context of disc and jet models.Comment: Accepted for publication in Astronomy and Astrophysics. 11 Figures, 3 Table

Assessing luminosity correlations via cluster analysis: Evidence for dual tracks in the radio/X-ray domain of black hole X-ray binaries

[abridged] The radio:X-ray correlation for hard and quiescent state black hole X-ray binaries is critically investigated in this paper. New observations of known sources, along with newly discovered ones, have resulted in an increasingly large number of outliers lying well outside the scatter about the quoted best-fit relation. Here, we employ and compare state of the art data clustering techniques in order to identify and characterize different data groupings within the radio:X-ray luminosity plane for 18 hard and quiescent state black hole X-ray binaries with nearly simultaneous multi-wavelength coverage. Linear regression is then carried out on the clustered data to infer the parameters of a relationship of the form {ell}_{r}=alpha+beta {ell}_x through a Bayesian approach (where {ell} denotes log lum). We conclude that the two cluster model, with independent linear fits, is a significant improvement over fitting all points as a single cluster. While the upper track slope (0.63\pm0.03) is consistent, within the errors, with the fitted slope for the 2003 relation (0.7\pm0.1), the lower track slope (0.98\pm0.08) is not consistent with the upper track, nor it is with the widely adopted value of ~1.4 for the neutron stars. The two luminosity tracks do not reflect systematic differences in black hole spins as estimated either from reflection, or continuum fitting method. These results are insensitive to the selection of sub-samples, accuracy in the distances, and to the treatment of upper limits. Besides introducing a further level of complexity in understanding the interplay between synchrotron and Comptonised emission from black hole X-ray binaries, the existence of two tracks in the radio:X-ray domain underscores that a high level of caution must be exercised when employing black hole luminosity relations for the purpose of estimating a third parameter, such as distance or mass.Comment: MNRAS, in press (10 pages, 7 figures

Is the plateau state in GRS 1915+105 equivalent to canonical hard states?

GRS1915+105 is a very peculiar black hole binary that exhibits accretion-related states that are not observed in any other stellar-mass black hole system. One of these states, however -- referred to as the plateau state -- may be related to the canonical hard state of black hole X-ray binaries. Both the plateau and hard state are associated with steady, relatively lower X-ray emission and flat/inverted radio emission, that is sometimes resolved into compact, self-absorbed jets. However, while generally black hole binaries quench their jets when the luminosity becomes too high, GRS1915+105 seems to sustain them despite the fact that it accretes at near- or super-Eddington rates. In order to investigate the relationship between the plateau and the hard state, we fit two multi-wavelength observations using a steady-state outflow-dominated model, developed for hard state black hole binaries. The data sets consist of quasi-simultaneous observations in radio, near-infrared and X-ray bands. Interestingly, we find both significant differences between the two plateau states, as well as between the best-fit model parameters and those representative of the hard state. We discuss our interpretation of these results, and the possible implications for GRS 1915+105's relationship to canonical black hole candidates.Comment: accepted for publication in MNRA

Combining 4D Flow MRI and Complex Networks Theory to Characterize the Hemodynamic Heterogeneity in Dilated and Non-dilated Human Ascending Aortas

Motivated by the evidence that the onset and progression of the aneurysm of the ascending aorta (AAo) is intertwined with an adverse hemodynamic environment, the present study characterized in vivo the hemodynamic spatiotemporal complexity and organization in human aortas, with and without dilated AAo, exploring the relations with clinically relevant hemodynamic and geometric parameters. The Complex Networks (CNs) theory was applied for the first time to 4D flow magnetic resonance imaging (MRI) velocity data of ten patients, five of them presenting with AAo dilation. The time-histories along the cardiac cycle of velocity-based quantities were used to build correlation-based CNs. The CNs approach succeeded in capturing large-scale coherent flow features, delimiting flow separation and recirculation regions. CNs metrics highlighted that an increasing AAo dilation (expressed in terms of the ratio between the maximum AAo and aortic root diameter) disrupts the correlation in forward flow reducing the correlation persistence length, while preserving the spatiotemporal homogeneity of secondary flows. The application of CNs to in vivo 4D MRI data holds promise for a mechanistic understanding of the spatiotemporal complexity and organization of aortic flows, opening possibilities for the integration of in vivo quantitative hemodynamic information into risk stratification and classification criteria