bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fibrilación auricular en pacientes con ataque cerebrovascular: experiencia en un centro de referencia del suroccidente colombiano
Authors: García Lina , Pérez Manuel , Amaya González Pablo 
Published: December 2016

Introducción: La fibrilación auricular se presenta como uno de los principales factores de riesgo para la presencia de eventos isquémicos cerebrales de origen cardioembólico, siendo cada vez mayor su prevalencia, especialmente por aumento de la edad poblacional. Este tipo de arritmia hace que sea necesario un tipo de prevención secundaria diferente a la realizada en otras patologías.
Objetivo: Describir las características de los pacientes con ataque cerebrovascular isquémico (ACV) y su relación con fibrilación auricular.
Materiales y métodos: Estudio descriptivo-retrospectivo de individuos con ACV isquémico. Se recolectó información sobre factores de riesgo para enfermedad cerebrovascular, presencia o no de fibrilación auricular y tratamiento recibido. Se realizaron tablas comparativas según la presencia o ausencia de fibrilación auricular. Se consideraron significativos los valores de p inferiores a 0,05.
Resultados: Se incluyeron 246 pacientes con una mediana de edad de 71 años, la mitad de sexo masculino. Entre los factores de riesgo para ACV isquémico la prevalencia de hipertensión arterial (HTA) fue 73,9%, ACV previo 23,9%, tabaquismo previo 20,7%. La prevalencia de fibrilación auricular fue del 24,3%, siendo mayor en pacientes con falla cardiaca concomitante (OR 3,5 95%; IC 1,6-7,75; p = 0,000). Se observó menor probabilidad de fibrilación auricular entre los hombres (OR 0,49 95%; IC 0,26-0,92 p = 0,018). La dilatación de la aurícula izquierda estuvo presente en el 43,1% de los individuos con ACV isquémico. De quienes recibían anticoagulantes orales, 57% tenían fibrilación auricular. Solo 15% de los pacientes cumplieron criterios para realizar trombólisis. La mortalidad por cualquier causa en pacientes con ACV isquémico fue de 13,8% y en el grupo de fibrilación auricular del 16%.
Conclusión: El ACV isquémico es una patología prevalente en nuestra población y aproximadamente uno de cada cinco pacientes con ACV presentan fibrilación auricular previa o diagnosticada de novo durante el evento. La mortalidad en este subgrupo fue del 16%.
Estado actual de la esclerosis múltiple en Colombia
Authors: Jiménez-Pérez Cheryl E. , Zarco-Montero Luis A. , Castañeda-Cardona Camilo , Otálora Esteban Margarita , Martínez Andrea , Rosselli Diego 
Published: December 2016

Introducción: Dos estudios epidemiológicos de esclerosis múltiple (EM) la describen como de bajo riesgo en Colombia. Hay, sin embargo, nuevos sistemas de información que permiten una aproximación más precisa.
Objetivo:Estimar la prevalencia nacional de EM, así como por regiones del país, y analizar los costos de los fármacos usados en Colombia.
Materiales y métodos: Se obtuvieron datos del Registro Individual de Prestación de Servicios de Salud (RIPS), con el código diagnóstico G35X para esclerosis múltiple, tomando los diagnósticos confirmados nuevos y repetidos entre 2009 y 2013, por sexo, grupo etario y departamento. Para el análisis de medicamentos se usó la base de datos Sismed del 2014, incluyendo los fármacos disponibles en Colombia: interferón beta-1A, interferón beta-1B, acetato de glatiramer, natalizumab, fingolimod y mitoxantrona.
Resultados:Según los RIPS, en Colombia se atendieron, en el período 2009-2013, un total de 3.462 personas con diagnóstico de esclerosis múltiple. La prevalencia nacional para el período fue de 7,52/100.000, con las cifras más altas en Bogotá (16,25), donde se atendieron 1.213 pacientes, seguido de los departamentos del Quindío (13,03) y Risaralda (11,18). La mayor proporción de pacientes se encuentra entre los 50 y 54 años de edad, y las mujeres representan más del 70%. Adicionalmente, en 2014 se invirtieron 86.000 millones de pesos (43 millones de dólares) en medicamentos para esclerosis múltiple, lo que equivale a cerca de 25 millones por paciente.
The learning curve in endoscopic endonasal resection of craniopharyngiomas
Authors: Kshettry Varun R. , Do Hyunwoo , Elshazly Khaled , Farrell Christopher J. , Nyquist Gurston , Rosen Marc , Evans James J. 
Published: December 2016

OBJECTIVE
There is a paucity of literature regarding the learning curve associated with performing endoscopic endonasal cranial base surgery. The purpose of this study was to determine to what extent a learning curve might exist for endoscopic endonasal resection in cases of craniopharyngiomas.

METHODS
A retrospective review was performed for all endoscopic endonasal craniopharyngioma resections performed at Thomas Jefferson University from 2005 to 2015. To assess for a learning curve effect, patients were divided into an early cohort (2005–2009, n = 20) and a late cohort (2010–2015, n = 23). Preoperative demographics, clinical presentation, imaging characteristics, extent of resection, complications, tumor control, and visual and endocrine outcomes were obtained. Categorical variables and continuous variables were compared using a 2-sided Fisher's exact test and t-test, respectively.

RESULTS
Only the index operation performed at the authors' institution was included. There were no statistically significant differences between early and late cohorts in terms of patient age, sex, presenting symptoms, history of surgical or radiation treatment, tumor size or consistency, hypothalamic involvement, or histological subtype. The rate of gross-total resection (GTR) increased over time from 20% to 65% (p = 0.005), and the rate of subtotal resection decreased over time from 40% to 13% (p = 0.078). Major neurological complications, including new hydrocephalus, meningitis, carotid artery injury, or stroke, occurred in 6 patients (15%) (8 complications) in the early cohort compared with only 1 (4%) in the late cohort (p = 0.037). CSF leak decreased from 40% to 4% (p = 0.007). Discharge to home increased from 64% to 95% (p = 0.024). Visual improvement was high in both cohorts (88% [early cohort] and 81% [late cohort]). Rate of postoperative panhypopituitarism and permanent diabetes insipidus both increased from 50% to 91% (p = 0.005) and 32% to 78% (p = 0.004), which correlated with a significant increase in intentional stalk sacrifice in the late cohort (from 0% to 70%, p < 0.001).

CONCLUSIONS
High rates of near- or total resection and visual improvement can be achieved using an endoscopic endonasal approach for craniopharyngiomas. However, the authors did find evidence for a learning curve. After 20 cases, they found a significant decrease in major neurological complications and significant increases in the rates of GTR rate and discharge to home. Although there was a large decrease in the rate of postoperative CSF leak over time, this was largely attributable to the inclusion of very early cases prior to the routine use of vascularized nasoseptal flaps. There was a significant increase in new panhypopituitarism and diabetes insipidus, which is attributable to increase rates of intentional stalk sacrifice.
A quantitative analysis of craniopharyngioma cyst expansion during and after radiation therapy and surgical implications
Authors: Lamiman Kelly , Wong Kenneth K. , Tamrazi Benita , Nosrati Jason D. , Olch Arthur , Chang Eric L. , Kiehna Erin N. 
Published: December 2016

OBJECTIVE
When complete resection of craniopharyngioma is not achievable or the sequelae are prohibitive, limited surgery and radiation therapy have demonstrated excellent local disease control while minimizing treatment-related sequelae. When residual tissue exists, there is a propensity for further cyst development and expansion during and after radiation therapy. This can result in obstructive hydrocephalus, visual changes, and/or clinical decline. The authors present a quantitative analysis of cyst expansion during and after radiotherapy and examine how it affected subsequent management.

METHODS
The authors performed an institutional review board–approved retrospective study of patients with histologically confirmed craniopharyngioma treated between 2000 and 2015 with surgery and intensity-modulated radiation therapy (IMRT) at a single institution. Volumetric measurements of cyst contours were generated by radiation oncology treatment planning software postoperatively, during IMRT, and up to 12 months after IMRT. Patient, tumor, and treatment–related variables were collected until the last known follow-up and were analyzed.

RESULTS
Twenty-seven patients underwent surgery and IMRT. The median total radiation dose was 54 Gy. Of the 27 patients, 11 patients (40.7%) demonstrated cyst expansions within 1 year of IMRT. Of note, all tumors with cyst expansion were radiographically Puget Grade 2. Maximal cyst expansion peaked at 4.27 months following radiation therapy, with a median volume growth of 4.1 cm3 (mean 9.61 cm3) above the postoperative cyst volume. Eight patients experienced spontaneous cyst regression without therapeutic intervention. Three patients experienced MRI-confirmed cyst enlargement during IMRT, all of whom required adaptive planning to ensure adequate coverage of the entire tumor volume. Two of these 3 patients required ventriculoperitoneal shunt placement and additional intervention. One underwent additional resection, and the other had placement of an intracystic catheter for aspiration and delivery of intracystic interferon within 12 months of completing IMRT. All 3 patients now have stable disease.

CONCLUSIONS
Craniopharyngioma cyst expansion occurred in approximately 40% of the patients during or after radiotherapy. In the majority of patients, cyst expansion was a self-limiting process and did not confer a worse outcome. During radiotherapy, cyst expansion may be apparent on image-guided radiation therapy. Adaptive IMRT planning may be required to ensure that the intended IMRT dose covers the entire tumor and cyst volume. The sequelae of cyst expansion include progressive hydrocephalus, which may be treated with a shunt. For patients with solitary cyst expansion, cyst aspiration and/or intracystic interferon may result in disease control.
Remarques sur l'acclimatation en France de Procambarus clarkii (Decapoda Cambaridae)
Authors: Laurent P.-J. , Leloirn H. , Neveu André 
Published: December 2016

Remarks on the acclimatization of Procambarus clarkii in France (Decapoda Cambaridae)
We observed populations of P. clarkii in several locations in South-Western part of France, the department Gard and Brittany. Although dense populations have been encountered ten years after acclimatization, this crayfish does not seem to have induce, until now, detectable migrations. Such a behaviour differs with Orconectes limosus's behaviour. Once settled in a place, O. limosus, moves quickly downstream through entire watershed, using, if necessary, canals as way of migration. French climatic conditions are probably not very favourable for P. clarkii, however some individuals develop adaptations and become able to multiply as soon as the conditions improve. Human interventions could however open widely the French continental waters to a generalized invasion of P. clarkii like in Spain. Such an event could be considered as a great threat on both the astacological situation and aquatic biota.
HEATING MECHANISMS IN THE LOW SOLAR ATMOSPHERE THROUGH MAGNETIC RECONNECTION IN CURRENT SHEETS
Authors: Ni Lei , Lin Jun , Roussev Ilia I. , Schmieder Brigitte 
Published: December 2016

ABSTRACT
We simulate several magnetic reconnection processes in the low solar chromosphere/photosphere; the radiation cooling, heat conduction and ambipolar diffusion are all included. Our numerical results indicate that both the high temperature (≳8 × 104 K) and low temperature (∼104 K) magnetic reconnection events can happen in the low solar atmosphere (100–600 km above the solar surface). The plasma β controlled by plasma density and magnetic fields is one important factor to decide how much the plasma can be heated up. The low temperature event is formed in a high β magnetic reconnection process, Joule heating is the main mechanism to heat plasma and the maximum temperature increase is only several thousand Kelvin. The high temperature explosions can be generated in a low β magnetic reconnection process, slow and fast-mode shocks attached at the edges of the well developed plasmoids are the main physical mechanisms to heat the plasma from several thousand Kelvin to over 8 × 104 K. Gravity in the low chromosphere can strongly hinder the plasmoid instability and the formation of slow-mode shocks in a vertical current sheet. Only small secondary islands are formed; these islands, however, are not as well developed as those in the horizontal current sheets. This work can be applied to understand the heating mechanism in the low solar atmosphere and could possibly be extended to explain the formation of common low temperature Ellerman bombs (∼104 K) and the high temperature Interface Region Imaging Spectrograph (IRIS) bombs (≳8 × 104) in the future.
A NEW APPROACH TO ANALYZING HST SPATIAL SCANS: THE TRANSMISSION SPECTRUM OF HD 209458 b
Authors: Tsiaras A. , Waldmann I. P. , Rocchetto M. , Varley R. , Morello G. , Damiano M. , Tinetti G. 
Published: December 2016

ABSTRACT
The Wide Field Camera 3 on the Hubble Space Telescope is currently one of the most widely used instruments for observing exoplanetary atmospheres, especially with the use of the spatial scanning technique. An increasing number of exoplanets have been studied using this technique as it enables the observation of bright targets without saturating the sensitive detectors. In this work, we present a new pipeline for analyzing the data obtained with the spatial scanning technique, starting from the raw data provided by the instrument. In addition to commonly used correction techniques, we take into account the geometric distortions of the instrument, the impact of which may become important when they are combined with the scanning process. Our approach can improve the photometric precision for existing data and also extend the limits of the spatial scanning technique, as it allows the analysis of even longer spatial scans. As an application of our method and pipeline, we present the results from a reanalysis of the spatially scanned transit spectrum of HD 209458 b. We calculate the transit depth per wavelength channel with an average relative uncertainty of 40 ppm. We interpret the final spectrum with

-REx, our fully Bayesian spectral retrieval code, which confirms the presence of water vapor and clouds in the atmosphere of HD 209458 b. The narrow wavelength range limits our ability to disentangle the degeneracies between the fitted atmospheric parameters. Additional data over a broader spectral range are needed to address this issue.
KOI-1003: A NEW SPOTTED, ECLIPSING RS CVN BINARY IN THE KEPLER FIELD
Authors: Roettenbacher Rachael M. , Kane Stephen R. , Monnier John D. , Harmon Robert O. 
Published: December 2016

ABSTRACT
Using the high-precision photometry from the Kepler space telescope, thousands of stars with stellar and planetary companions have been observed. The characterization of stars with companions is not always straightforward and can be contaminated by systematic and stellar influences on the light curves. Here, through a detailed analysis of starspots and eclipses, we identify KOI-1003 as a new, active RS CVn star—the first identified with data from Kepler. The Kepler light curve of this close binary system exhibits the system’s primary transit, secondary eclipse, and starspot evolution of two persistent active longitudes. The near equality of the system’s orbital and rotation periods indicates the orbit and primary star’s rotation are nearly synchronized (

;

). By assuming the secondary star is on the main sequence, we suggest the system consists of a

subgiant primary and a

main-sequence companion. Our work gives a distance of 4400 ± 600 pc and an age of

, parameters which are discrepant with previous studies that included the star as a member of the open cluster NGC 6791.
TOMOGRAPHIC SEPARATION OF COMPOSITE SPECTRA. XII. THE PHYSICAL PROPERTIES AND SPECTRAL PHASE VARIABILITY OF THE MASSIVE CLOSE BINARY HD 159176
Authors: Penny Laura R. , Epps Jacob G. , Snyder Joseph D. 
Published: December 2016

ABSTRACT
We present our analysis of the double-lined, O-binary HD 159176 based on observations made with the International Ultraviolet Explorer (IUE). We use cross-correlation methods to obtain radial velocities, confirm the orbital elements, and estimate the UV flux ratio. In addition, we cross-correlate specific regions of the IUE spectra corresponding to Fe v, Fe iv, He ii, N iii, and O iv features to determine the phase dependence of the cross-correlation strength for those features. We tomographically reconstruct the individual component spectra, which we classify as O6.5 V + O7 V. We present the first light-curve analysis of observations from the HIPPARCOS satellite combined with data from Thomas & Pachoulakis and determine an orbital inclination,

. Both stars are well within their Roche surfaces. Our derived masses,

and

, are constrained by the known distance and reddening to NGC 6383 and the derived optical flux ratio, and agree within errors with predicted evolutionary masses. Both components display phase variations corresponding to the classical Struve–Sahade effect in the UV, Fe iv, N iii, and O iv cross-correlation functions. The Fe v features have remarkably uniform profile strengths except in observations prior to conjunctions, a possible post-quadrature Struve–Sahade effect. The derived orbital elements from the various ions are not affected by the Struve–Sahade variability. Both the spectral variability and derived orbital semi-amplitudes of He ii

suggest that this feature is formed preferentially on the inner hemispheres of the component stars.
SURFACE DENSITY EFFECTS IN QUENCHING: CAUSE OR EFFECT?
Authors: Lilly Simon J. , Carollo C. Marcella 
Published: December 2016

ABSTRACT
There are very strong observed correlations between the specific star formation rates (sSFRs) of galaxies and their mean surface mass densities, Σ, as well as other aspects of their internal structure. These strong correlations have often been taken to argue that the internal structure of a galaxy must play a major physical role, directly or indirectly, in the control of star formation. In this paper we show by means of a very simple toy model that these correlations can arise naturally without any such physical role once the observed evolution of the size–mass relation for star-forming galaxies is taken into account. In particular, the model reproduces the sharp threshold in Σ between galaxies that are star-forming and those that are quenched and the evolution of this threshold with redshift. Similarly, it produces iso-quenched-fraction contours in the f
Q(m, R
e) plane that are almost exactly parallel to lines of constant Σ for centrals and shallower for satellites. It does so without any dependence on quenching on size or Σ and without invoking any differences between centrals and satellites, beyond the different mass dependences of their quenching laws. The toy model also reproduces several other observations, including the sSFR gradients within galaxies and the appearance of inside-out build-up of passive galaxies. Finally, it is shown that curvature in the main-sequence sSFR–mass relation can produce curvature in the apparent B/T ratios with mass. Our analysis therefore suggests that many of the strong correlations that are observed between galaxy structure and sSFR may well be a consequence of things unrelated to quenching and should not be taken as evidence of the physical processes that drive quenching.
HIERARCHICAL GALAXY GROWTH AND SCATTER IN THE STELLAR MASS–HALO MASS RELATION
Authors: Gu (顾梦) Meng , Conroy Charlie , Behroozi Peter 
Published: December 2016

ABSTRACT
The relation between galaxies and dark matter halos reflects the combined effects of many distinct physical processes. Observations indicate that the z = 0 stellar mass–halo mass (SMHM) relation has remarkably small scatter in stellar mass at fixed halo mass (≲0.2 dex), with little dependence on halo mass. We investigate the origins of this scatter by combining N-body simulations with observational constraints on the SMHM relation. We find that at the group and cluster scale (

M

vir

>

10

14

M

⊙

) the scatter due purely to hierarchical assembly is

≈
0.16

dex, which is comparable to recent direct observational estimates. At lower masses, mass buildup since

z
≈
2

is driven largely by in situ growth. We include a model for the in situ buildup of stellar mass and find that an intrinsic scatter in this growth channel of 0.2 dex produces a relation between scatter and halo mass that is consistent with observations from

10

12

M

⊙

<

M

vir

<

10

14.75

M

⊙

. The approximately constant scatter across a wide range of halo masses at z = 0 thus appears to be a coincidence, as it is determined largely by in situ growth at low masses and by hierarchical assembly at high masses. These results indicate that the scatter in the SMHM relation can provide unique insight into the regularity of the galaxy formation process.
MILLIMETER/SUBMILLIMETER SPECTROSCOPY OF TiO (X3Δr): THE RARE TITANIUM ISOTOPOLOGUES
Authors: Lincowski A. P. , Halfen D. T. , Ziurys L. M. 
Published: December 2016

ABSTRACT
Pure rotational spectra of the rare isotopologues of titanium oxide, 46TiO, 47TiO, 49TiO, and 50TiO, have been recorded using a combination of Fourier transform millimeter-wave (FTmmW) and millimeter/submillimeter direct absorption techniques in the frequency range 62–538 GHz. This study is the first complete spectroscopic characterization of these species in their X
3Δ
r
ground electronic states. The isotopologues were created by the reaction of N2O or O2 and titanium vapor, produced either by laser ablation or in a Broida-type oven, and observed in the natural Ti isotopic abundances. Between 10 and 11 rotational transitions J + 1

J were measured for each species, typically in all 3 spin–orbit ladders Ω = 1, 2, and 3. For 47TiO and 49TiO, hyperfine structure was resolved, originating from the titanium-47 and titanium-49 nuclear spins of I = 5/2 and 7/2, respectively. For the Ω = 1 and 3 components, the hyperfine structure was found to follow a classic Landé pattern, while that for Ω = 2 appeared to be perturbed, likely a result of mixing with the nearby isoconfigurational a
1Δ state. The spectra were analyzed with a case (a) Hamiltonian, and rotational, spin–orbit, and spin–spin parameters were determined for each species, as well as magnetic hyperfine and electric quadrupole constants for the two molecules with nuclear spins. The most abundant species, 48TiO, has been detected in circumstellar envelopes. These measurements will enable other titanium isotopologues to be studied at millimeter wavelengths, providing Ti isotope ratios that can test models of nucleosynthesis.
ALMA REVEALS POTENTIAL LOCALIZED DUST ENRICHMENT FROM MASSIVE STAR CLUSTERS IN II Zw 40
Authors: Consiglio S. Michelle , Turner Jean L. , Beck Sara , Meier David S. 
Published: December 2016

ABSTRACT
We present subarcsecond images of submillimeter CO and continuum emission from a local galaxy forming massive star clusters: the blue compact dwarf galaxy II Zw 40. At ∼0.″4 resolution (20 pc), the CO(3-2), CO(1-0), 3 mm, and 870 μm continuum maps illustrate star formation on the scales of individual molecular clouds. Dust contributes about one-third of the 870 μm continuum emission, with free–free accounting for the rest. On these scales, there is not a good correspondence between gas, dust, and free–free emission. Dust continuum is enhanced toward the star-forming region as compared to the CO emission. We suggest that an unexpectedly low and spatially variable gas-to-dust ratio is the result of rapid and localized dust enrichment of clouds by the massive clusters of the starburst.