A class of new solutions for Einstein’s field equations, by choosing the ansatz e?(r)=1+kr2R21+r2R2 metric potential, are obtained under Karmarkar condition. It is found that a number pulsars like 4U 1820-30, PSR J1903+327, 1608-52, Vela X-1, J1614-2230, Cen X-3 can be accomodated in this model. We have displayed nature physical parameters and energy conditions throughout distribution using num...

El Trienio Liberal (1820-1823) es ampliamente conocido por ser el segundo régimen constitucional de la historia España, inaugurado gracias al triunfo del pronunciamiento Riego en enero 1820. En ese sentido, sobre él gravitan las enormes dificultades que tuvieron los liberales para poner marcha un Estado alternativo absolutista, Fernando VII se sintió, además profundamente incómodo, también caut...

The type of Lasiocampa decolorata (KLUG, 1830), collected in 1820, was successfully barcoded to generate a 658bp COI-fragment after 194 years. The resulting molecular data allowed the description of two closely related species from Morocco: Lasiocampa hannae SPEIDEL, MOOSER & WITT sp. n. from the Anti Atlas and Lasiocampa editae SPEIDEL, MOOSER & WITT sp. n. from the High Atlas.

Entre 1815 y mediados de la década 1820 mayoría los pueblos o ciudades rioplatenses, protagonistas del proceso revolucionario, se separó sus demarcaciones provinciales proclamó también su independencia soberanía. Las historiografías políticas sobre estas trayectorias, denominadas “procesos autonomía provincial”, atribuyeron sentidos posteriores a experiencias que contuvieron modulaciones divers...

We have discovered a 7.06±0.08 Hz quasi-periodic oscillation (QPO) in the X-ray flux of the lowluminosity low-mass X-ray binary (LMXB) and atoll source 4U 1820–30. This QPO was only observable at the highest observed mass accretion rate, when the source was in the uppermost part of the banana branch, at a 2–25 keV luminosity of 5.4×10 erg s (for a distance of 6.4 kpc). The QPO had a FWHM of onl...

Historical studies enable understanding past facts that may justify some reflections about the present, as well taking back important professional and scientific characters events in history. Among them, one finds Sebastião Ferreira Soares, who lived Imperial Brazil dedicated more than 40 years of his life working studying to understand present existing accounting practices time, point out weak...