Optical Photometry of the Type Ia SN 1999ee and the Type Ib/c SN 1999ex in IC 5179

We present UBVRIz lightcurves of the Type Ia SN 1999ee and the Type Ib/c SN 1999ex, both located in the galaxy IC 5179. SN 1999ee has an extremely well sampled lightcurve spanning from 10 days before Bmax through 53 days after peak. Near maximum we find systematic differences ~0.05 mag in photometry measured with two different telescopes, even though the photometry is reduced to the same local standards around the supernova using the specific color terms for each instrumental system. We use models for our bandpasses and spectrophotometry of SN 1999ee to derive magnitude corrections (S-corrections) and remedy this problem. This exercise demonstrates the need of accurately characterizing the instrumental system before great photometric accuracies of Type Ia supernovae can be claimed. It also shows that this effect can have important astrophysical consequences since a small systematic shift of 0.02 mag in the B-V color can introduce a 0.08 mag error in the extinction corrected peak B magnitudes of a supernova and thus lead to biased cosmological parameters. The data for the Type Ib/c SN 1999ex present us with the first ever observed shock breakout of a supernova of this class. These observations show that shock breakout occurred 18 days before Bmax and support the idea that Type Ib/c supernovae are due to core collapse of massive stars rather than thermonuclear disruption of white dwarfs.Comment: 55 pages, 15 figures, accepted by the Astronomical Journa

Manejo terapéutico y diagnóstico en equipo multidisciplinario y resultados obtenidos en gestantes con cardiopatía orgánica

Las enfermedades cardiovasculares afectan aproximadamente al 2% de las mujeres embarazadas, por lo que suponen un aumento del riesgo tanto para la madre como para el feto. El embarazo y el parto producen cambios fisiológicos sustanciales que requieren de una adecuada adaptación del sistema cardiovascular. Estos cambios fisiológicos que son muy bien tolerados en las gestantes sin cardiopatía, exponen a la mujer con enfermedad cardiovascular a eventos clínicos significativos. Este es un trabajo descriptivo, retrospectivo, de casos consecutivos de pacientes que acudieron a la División de Medicina Cardiovascular, del Hospital de Clínicas en un período comprendido entre Agosto de 2013 a Junio de 2014. Incluye a 5 pacientes embarazas y portadoras de cardiopatías conocidas o desconocidas. La edad promedio fue de 27 años, rango etario de 17 a 36 años. La edad gestacional al momento de la consulta fue de 34 semanas por fecha de última menstruación, menor edad gestacional 30 semanas y mayor edad gestacional 38 semanas. El síntoma principal de consulta fue la disnea (100%), edema de miembros inferiores en 3 pacientes (60%), y palpitaciones en 2 pacientes (40%). El manejo diagnóstico y terapéutico conjunto con un seguimiento detallado y adecuado por un equipo multidisciplinario de cardiólogos, clínicos, ginecólogos, anestesiólogos y cirujanos cardiovasculares facilitan una buena evolución clínica y un desenlace exitoso del embarazo y parto de la gestante con la cardiopatía orgánica. Como resultado de este manejo multidisciplinario todos los recién nacidos tuvieron buena evolución durante su permanencia en la unidad de cuidados intensivos sin inconvenientes

Optical and Infrared Photometry of the Type Ia Supernovae 1991T, 1991bg, 1999ek, 2001bt, 2001cn, 2001cz, and 2002bo

We present optical and/or infrared photometry of the Type Ia supernovae SN 1991T, SN 1991bg, SN 1999ek, SN 2001bt, SN 2001cn, SN 2001cz, and SN 2002bo. All but one of these supernovae have decline rate parameters Delta m_15(B) close to the median value of 1.1 for the whole class of Type Ia supernovae. The addition of these supernovae to the relationship between the near-infrared absolute magnitudes and Delta m_15(B) strengthens the previous relationships we have found, in that the maximum light absolute magnitudes are essentially independent of the decline rate parameter. (SN 1991bg, the prototype of the subclass of fast declining Type Ia supernovae, is a special case.) The dispersion in the Hubble diagram in JHK is only ~0.15 mag. The near-infrared properties of Type Ia supernovae continue to be excellent measures of the luminosity distances to the supernova host galaxies, due to the need for only small corrections from the epoch of observation to maximum light, low dispersion in absolute magnitudes at maximum light, and the minimal reddening effects in the near-infrared.Comment: Astron. J., 128, 3034 (Dec. 2004). This version with updated author list, addresses, acknowledgments, reference

Reforms and Counter-Reforms in Bolivia

This paper analyzes reforms and counter-reforms in Bolivia in recent decades and their effects on the policymaking process (PMP) and productivity. Bolivias PMP has shifted from a formal representative democracy to a participative and direct type of democracy where street protest and other non-conventional forms of political participation have become dominant. While reforms have increased productivity, they have failed to secure the political support necessary to assure long-term sustainability. In contrast, counter-reforms have so far enjoyed extensive political support, but productivity has stagnated since this process started, with declining economic growth and job creationdevelopments likely to undermine support for the counter-reform process. The document stresses the need to rebuild a consensus around a PMP capable of increasing productivity and employment creation while restoring social cohesion

Successful double valve replacement in a pregnant woman with refractory heart failure due to early dysfunction of the biological prosthesis in the aortic valve position

Rheumatic fever continues to be a frequent cause of cardiac valve disease in developing countries. The combination of rheumatic heart disease and pregnancy represents a challenge in the management of these patients. Prevention strategies are often insufficient; this is why we continue to observe complicated cases that demand more complex treatments. We are reporting the case of a 20-year-old woman, with a history of aortic valve replacement and mitral valve repair due to rheumatic heart disease. Two years later after her valve replacement, she attended consultation with signs and symptoms of heart failure in functional class III during a pregnancy of 20 weeks. The echocardiography showed: dysfunctional biological aortic prosthesis with severe stenosis and moderate regurgitation (central and para-valve leak), as well as severe mitral valve insufficiency, eccentric, directed towards the atrial free wall. She was admitted, and received optimal medical treatment for 4 weeks with little response and subsequent worsening. A multidisciplinary committee was formed including cardiologists, cardiac surgeons, obstetricians, neonatologists, and specialists in bioethics. It was decided to proceed with valve replacement surgery during the 21st week of her gestation. Successful double valve replacement (mitral and aortic) was performed, without complications for the patient or the fetus. She was discharged in good health. In her 38th week of gestation, a successful cesarean delivery was performed without any complications.</p

The relation between QRS complex fragmentation and segmental abnormalities of the myocardial contractility in patients with coronary artery disease

Background: Fragmented QRS (fQRS) is defined as any QRS complex with duration of less than 120 ms (ms) and at least one notch in the R or S wave in two or more leads belonging to the same coronary territory. The fQRS represents a delay in ventricular conduction caused by a myocardial scar associated to arrhythmic events. Methods: This is a descriptive, retrospective, cross-sectional study of a total of 123 patientsadmitted with ischemic heart disease. The aim was to correlate the presence of fQRS in a conventional 12-leads electrocardiogram (ECG) with myocardial regional motility disorders. Results: A total of 62% of the patients were male, the mean age was 63 ± 12 SD. fQRS was observed in 44% (64% men and 36% women), the most frequent location being the inferior wall (61%), followed by the anteroseptal and lateral walls (14% for both). Of the 36 patients with fQRS, 30 had segmental disorders, while 6 did not. Of the 45 patients without fQRS, 28 had segmental disorders, but 17 did not, which gives us a sensitivity of 52% (moderate SnNout) and specificity of 74% (high SpPin), with a positive predictive value of 83%, a negative predictive value of 38% and a prevalence of 72%. Conclusion: The presence of fQRS in the ECG has high specificity and a high positive predictive value of the existence of segmental myocardial motility disorders in patients with documented coronary artery disease

Exploring Mannosylpurines as Copper Chelators and Cholinesterase Inhibitors with Potential for Alzheimer’s Disease

Alzheimer’s Disease (AD) is characterized by a progressive cholinergic neurotransmission imbalance, with a decrease of acetylcholinesterase (AChE) activity followed by a significant increase of butyrylcholinesterase (BChE) in the later AD stages. BChE activity is also crucial for the development of Aβ plaques, the main hallmarks of this pathology. Moreover, systemic copper dyshomeostasis alters neurotransmission leading to AD. In the search for structures targeting both events, a set of novel 6-benzamide purine nucleosides was synthesized, differing in glycone configuration and N7/N9 linkage to the purine. Their AChE/BChE inhibitory activity and metal ion chelating properties were evaluated. Selectivity for human BChE inhibition required N9-linked 6-deoxy-α-d-mannosylpurine structure, while all three tested β-d-derivatives appeared as non-selective inhibitors. The N9-linked l-nucleosides were cholinesterase inhibitors except the one embodying either the acetylated sugar or the N-benzyl-protected nucleobase. These findings highlight that sugar-enriched molecular entities can tune bioactivity and selectivity against cholinesterases. In addition, selective copper chelating properties over zinc, aluminum, and iron were found for the benzyl and acetyl-protected 6-deoxy-α-l-mannosyl N9-linked purine nucleosides. Computational studies highlight molecular conformations and the chelating molecular site. The first dual target compounds were disclosed with the perspective of generating drug candidates by improving water solubility

Desolación y nuevos vínculos sociales

La inquietud a las cual se ha buscado dar respuesta en este número de la revista es sobre la existencia, todavía, de posibilidades para la autonomía y/o el despliegue de proyectos autónomos, en un momento histórico en el cual la imposición de un pensamiento único y la homogeneización inmisericorde a través del consumo, es realizada mediante la globalización de los mercados y la unificación del espacio mundial. ¿Existe aún espacio para que la subjetividad de las personas y el deseo no sean subordinados por las formas de consumo impulsadas desde la publicidad y el marketing? ¿Ha logrado el capitalismo conquistar el deseo? ¿Subsisten aún espacios de la vida no colonizados por la economía mercantil? ¿Son posibles otras formas de globalización, no destructivas e insolidarias, como la que actualmente experimentamos? Han sido preguntas como éstas las que inspiraron la realización de este segundo número de Polis. Si bien creemos que éste es un debate que recién se inicia, tenemos la convicción de haber logrado reunir un conjunto de aportes intelectuales que pueden abrir paso a una tarea propia de la universidad, y a la vez necesaria e intransferible: criticar a partir de un debate democrático, mediante el diálogo y la confrontación de ideas, una forma de vida profundamente excluyente para muchos seres humanos, insustentable económica y ambientalmente en el mediano y largo plazo, crecientemente antidemocrática en su gestión, y destructora de identidades, de lenguas y de relaciones de convivialidad