Convergence: A Story of Quantiles and Spillovers

In this paper, we revisit the analysis of cross-country convergence by combining spatial econometrics and panel quantile regressions to estimate conditional -convergence models. Moreover, we use both exogenous and endogenous weight matrices. Our results show that indeed the effects of initial per capita income, investment rate, population growth and human capital on growth rates vary considerably across the estimated quantiles. Convergence is not a generalized phenomenon across the conditional growth distribution. Moreover, while using exogenous spatial weight matrices does not substantially alter the findings found in a-spatial models, it appears that endogenous weights dramatically affect the estimates of the convergence process

Mohs Surgery Outside Usual Indications: A Review

The body of literature supporting the use of Mohs micrographic surgery (MMS) in tumors outside the main indications (basal cell carcinoma, squamous cell carcinoma, dermatofibrosacroma protuberans, lentigo maligna) is constantly growing, but it is still based on case reports, case series, or at best institutional case series that focus on a single malignancy. Our aim in this review was to assess use of MMS in an array of rare tumors outside the usual indications. A review was performed using the MEDLINE database and the search engine ClinicalKey®. We reviewed the use of MMS on atypical fibroxanthoma (AFX)/malignant fibrous histiocytoma, microcystic adnexal carcinoma, extramammary Paget’s disease, Merkel cell carcinoma, pocrine/eccrine carcinoma/porocarcinoma, trichilemmal carcinoma, leiomyosarcoma, and angiosarcoma. Mohs micrographic surgery appears to be scarcely used in these tumors due to their low incidence. It is mainly performed for tumors in the H-zone of the face, and can be performed safely. The overall recurrence rate is lower compared with simple or wide local excision. MMS should be used in a more generalized fashion for these tumors

Mohs Surgery Outside Usual Indications: A Review

The body of literature supporting the use of Mohs micrographic surgery (MMS) in tumors outside the main indications (basal cell carcinoma, squamous cell carcinoma, dermatofibrosacroma protuberans, lentigo maligna) is constantly growing, but it is still based on case reports, case series, or at best institutional case series that focus on a single malignancy. Our aim in this review was to assess use of MMS in an array of rare tumors outside the usual indications. A review was performed using the MEDLINE database and the search engine ClinicalKey®. We reviewed the use of MMS on atypical fibroxanthoma (AFX)/malignant fibrous histiocytoma, microcystic adnexal carcinoma, extramammary Paget’s disease, Merkel cell carcinoma, pocrine/eccrine carcinoma/porocarcinoma, trichilemmal carcinoma, leiomyosarcoma, and angiosarcoma. Mohs micrographic surgery appears to be scarcely used in these tumors due to their low incidence. It is mainly performed for tumors in the H-zone of the face, and can be performed safely. The overall recurrence rate is lower compared with simple or wide local excision. MMS should be used in a more generalized fashion for these tumors

Solidificación de aminoácidos en la captura de CO2

Los procesos de captura de CO2 son muy importantes ya que permiten reducir las emisiones de CO2 a la atmósfera, por ejemplo las que realizanlas plantas de producción de energía. Los aminoácidos son unos compuestos químicos que se pueden utilizar para la absorción de CO2 y que pueden ayudar a mejorar la captura de CO2. La solidificación de estas especies en los sistemas de absorción empleados para capturar el CO2 puede ser un problema importante al poder dañar el equipo, o un beneficio,ya que se podría emplear para aumentar la captura del dióxido de carbono. Por ello es importante conocer en qué condiciones puede tener lugar la solidificación. La solidificación puede provenir de la congelación o de la precipitación. Por ello en este trabajo se han determinadolos puntos de congelación y solubilidades con el fin de determinar la solidificación de los aminoácidos. Se utilizan aminoácidos como el glicinato de sodio y el glicinato de potasio

Truncation of the Inner Accretion Disk around a Black Hole at Low Luminosity

Most black hole binaries show large changes in X-ray luminosity caused primarily by variations in mass accretion rate. An important question for understanding black hole accretion and jet production is whether the inner edge of the accretion disk recedes at low accretion rate. Measurements of the location of the inner edge (Rin) can be made using iron emission lines that arise due to fluorescence of iron in the disk, and these indicate that Rin is very close to the black hole at high and moderate luminosities (near 1% of the Eddington luminosity, Ledd). Here, we report on X-ray observations of the black hole GX 339-4 in the hard state by Suzaku and the Rossi X-ray Timing Explorer (RXTE) that extend iron line studies to 0.14% Ledd and show that Rin increases by a factor of >27 over the value found when GX 339-4 was bright. The exact value of Rin depends on the inclination of the inner disk (i), and we derive 90% confidence limits of Rin > 35 Rg at i = 0 degrees and Rin > 175 Rg at i = 30 degrees. This provides direct evidence that the inner portion of the disk is not present at low luminosity, allowing for the possibility that the inner disk is replaced by advection- or magnetically-dominated accretion flows.Comment: Accepted for ApJ Letters, 5 pages, 4 figure

AMUSE-Virgo II. Down-sizing in black hole accretion

(Abridged) We complete the census of nuclear X-ray activity in 100 early type Virgo galaxies observed by the Chandra X-ray Telescope as part of the AMUSE-Virgo survey, down to a (3sigma) limiting luminosity of 3.7E+38 erg/s over 0.5-7 keV. The stellar mass distribution of the targeted sample, which is mostly composed of formally `inactive' galaxies, peaks below 1E+10 M_Sun, a regime where the very existence of nuclear super-massive black holes (SMBHs) is debated. Out of 100 objects, 32 show a nuclear X-ray source, including 6 hybrid nuclei which also host a massive nuclear cluster as visible from archival HST images. After carefully accounting for contamination from nuclear low-mass X-ray binaries based on the shape and normalization of their X-ray luminosity function, we conclude that between 24-34% of the galaxies in our sample host a X-ray active SMBH (at the 95% C.L.). This sets a firm lower limit to the black hole occupation fraction in nearby bulges within a cluster environment. At face value, the active fraction -down to our luminosity limit- is found to increase with host stellar mass. However, taking into account selection effects, we find that the average Eddington-scaled X-ray luminosity scales with black hole mass as M_BH^(-0.62^{+0.13}_{-0.12}), with an intrinsic scatter of 0.46^({+0.08}_{-0.06}) dex. This finding can be interpreted as observational evidence for `down-sizing' of black hole accretion in local early types, that is, low mass black holes shine relatively closer to their Eddington limit than higher mass objects. As a consequence, the fraction of active galaxies, defined as those above a fixed X-ray Eddington ratio, decreases with increasing black hole mass.Comment: Accepted for publication in ApJ (no changes wrt v1

Fossil Gas and the Electromagnetic Precursor of Supermassive Binary Black Hole Mergers

Using a one-dimensional height integrated model, we calculate the evolution of an unequal mass binary black hole with a coplanar gas disk that contains a gap due to the presence of the secondary black hole. Viscous evolution of the outer circumbinary disk initially hardens the binary, while the inner disk drains onto the primary (central) black hole. As long as the inner disk remains cool and thin at low $\dot{M}_{\rm ext}$ (rather than becoming hot and geometrically thick), the mass of the inner disk reaches an asymptotic mass typically \sim 10^{-3}-10^{-4}\Msun. Once the semimajor axis shrinks below a critical value, angular momentum losses from gravitational waves dominate over viscous transport in hardening the binary. The inner disk then no longer responds viscously to the inspiraling black holes. Instead, tidal interactions with the secondary rapidly drive the inner disk into the primary. Tidal and viscous dissipation in the inner disk lead to a late time brightening in luminosity $L\propto t_{\rm minus}^{5/4}$, where $t_{\rm minus}$ is the time prior to the final merger. This late time brightening peaks $\sim 1$ day prior to the final merger at $\sim 0.1 L_{\rm Edd}$. This behavior is relatively robust because of self regulation in the coupled viscous-gravitational evolution of such binary systems. It constitutes a unique electromagnetic signature of a binary supermassive black hole merger and may allow the host galaxy to be identified if used in conjunction with the Laser Interferometric Space Antenna (LISA) localization.Comment: 11 pages, 6 figures, submitted to MNRA

The Strayed Reveller, No. 7

The seventh issue of The Strayed Reveller.https://scholarworks.sfasu.edu/reveller/1006/thumbnail.jp

Raising the bar (9)

This editorial summarizes the papers published in issue 13(4) so as to raise the bar in applied spatial economic research and highlight new trends. The first paper develops an economic geography model with trade costs in all sectors and different shares of unskilled labour in all locations. The second paper translates an economic geography model into a dynamic spatial econometric model and then estimates the unknown parameters to test for congestion spillover effects among Chinese cities. The following paper also investigates spillover effects, but of sovereign and banking risks across countries. The fourth paper empirically examines if a higher market potential results in higher average productivity and lower productivity dispersion of Italian retailers. The fifth paper demonstrates that modelling more than one spatial lag in the independent variables, using different specifications of the spatial weight matrix, can be used as a tool to correct for an omitted variable bias. The final paper develops a test for the existence of non-parametric non-linearities in a linear spatial econometric model