102 research outputs found
Workplans: workshop on planetary nebula observations
This workshop is the second of the WORKPLANS series, which we started in 2016. The main
goal of WORKPLANS is to build up a network of planetary nebulae (PNe) experts to address the main
open questions in the field of PNe research. The specific aims of the WORKPLANS workshop series
are (i) to discuss and prioritize the most important topics to be investigated by the PN community in
the following years; (ii) to establish a network of excellent researchers with complementary expertise;
(iii) to formulate ambitious observing proposals for the most advanced telescopes and instrumentation
presently available (ALMA, SOFIA, VLT, GTC, HST, etc.), addressing those topics; and (iv) to develop
strategies for major proposals to future observatories (JWST, ELT, SPICA, Athena, etc.). To achieve
these goals, WORKPLANS II brought together experts in all key sub-areas of the PNe research field,
namely: analysis and interpretation of PNe observational data; theoretical modeling of gas and
dust emission; evolution from Asymptotic Giant Branch stars (PNe progenitors) to PNe; and the
instrumentation and technical characteristics of the relevant observatoriesI.A. acknowledges the support of Coordenação de Aperfeiçoamento de Pessoal de Nível
Superior—Brasil (CAPES)—Finance Code 001. This research is supported by Space Telescope Science Institute
grant HST-GO-15953.001-A to RIT (J.K.). T.U. was supported by NASA under grant NNX15AF24G issued
through the Science Mission Directorate. E.V. acknowledges support from the “On the rocks II project” funded
by the Spanish Ministerio de Ciencia, Innovación y Universidades under grant PGC2018-101950-B-I00. The Workshop was organized with the financial support of the Lorentz Center, which was provided by the Netherlands
Organization for Scientific Research (NWO) and the Leiden Universit
The Herschel Planetary Nebula Survey (HerPlaNS) - a comprehensive dusty photoionization model of NGC6781
We perform a comprehensive analysis of the planetary nebula (PN) NGC6781 to
investigate the physical conditions of each of its ionized, atomic, and
molecular gas and dust components and the object's evolution, based on
panchromatic observational data ranging from UV to radio. Empirical nebular
elemental abundances, compared with theoretical predictions via nucleosynthesis
models of asymptotic giant branch (AGB) stars, indicate that the progenitor is
a solar-metallicity, 2.25-3.0 Msun initial-mass star. We derive the best-fit
distance of 0.46 kpc by fitting the stellar luminosity (as a function of the
distance and effective temperature of the central star) with the adopted
post-AGB evolutionary tracks. Our excitation energy diagram analysis indicate
high excitation temperatures in the photodissociation region (PDR) beyond the
ionized part of the nebula, suggesting extra heating by shock interactions
between the slow AGB wind and the fast PN wind. Through iterative fitting using
the Cloudy code with empirically-derived constraints, we find the best-fit
dusty photoionization model of the object that would inclusively reproduce all
of the adopted panchromatic observational data. The estimated total gas mass
(0.41 Msun) corresponds to the mass ejected during the last AGB thermal pulse
event predicted for a 2.5 Msun initial-mass star. A significant fraction of the
total mass (about 70 percent) is found to exist in the PDR, demonstrating the
critical importance of the PDR in PNe that are generally recognized as the
hallmark of ionized/H+ regions.Comment: 34 pages, 13 Figures and 16 Tables, accepted for publication in the
Astrophysical Journal Supplement Serie
Capacitación tributaria y su efecto en la determinación del impuesto a la renta de cuarta categoría a las directoras de la Empresa Representaciones CARYSUN E.I.R.L., Sullana 2020
La presente investigación tuvo como objetivo determinar el efecto de la capacitación
tributaria en la determinación del Impuesto a la Renta de cuarta categoría de las
directoras de la empresa Representaciones Carysun E.I.R.L. La metodología
desarrollada es aplicativa correlacional, teniendo como muestra a 20 personas, se
empleó para la recolección de datos como instrumento a la encuesta. Se planteó
como hipótesis que la capacitación tributaria genera un efecto positivo en la
determinación del impuesto a la renta de cuarta categoría en las directoras de la
empresa Representaciones Carysun E.I.R.L. Los resultados obtenidos a través de la
Prueba U de Mann-Whitney, revelaron que antes de la aplicación de la capacitación
tributaria a las directoras, en la tabla 15, el nivel de probabilidad fue de 0,912 siendo
superior al nivel de probabilidad de 0.05, por ende se determina que la capacitación
tributaria no genera un efecto positivo en la determinación del impuesto a la renta de
cuarta categoría, mientras que el post test se obtuvo una probabilidad de 0.007 siendo
menor a la probabilidad de 0.05 por lo tanto se determina que las directoras obtuvieron
un alto nivel de aprendizaje. Por ello se concluye que es importante que toda persona,
que comience a realizar una actividad económica, entre a un proceso de capacitación
tributaria continua que vaya de acuerdo a sus necesidades.The objective of this research was to determine the effect of tax training in the
determination of the fourth category income tax of the directors of the company
Representaciones Carysun E.I.R.L. The methodology developed is correlational
applicative, having as a sample 20 people, it was used for data collection as a survey
instrument. It was hypothesized that tax training generates a positive effect in the
determination of the fourth category income tax in the directors of the company
Representaciones Carysun E.I.R.L. The results obtained through the Mann-Whitney
U Test, revealed that before the application of the tax training to the directors, in table
15, the probability level was 0.912, being higher than the probability level of 0.05, by
Thus, it is determined that the tax training does not generate a positive effect in the
determination of the fourth category income tax, while the post-test obtained a
probability of 0.007 being less than the probability of 0.05, therefore it is determined
that the directors they obtained a high level of learning. Therefore, it is concluded that
it is important that every person, who begins to carry out an economic activity, enters
a process of continuous tax training that is according to their needs.Tesi
Análisis de la Sección 28 de las NIIF para las PYMES “Beneficios a Empleados” en la contabilidad de la Empresa ARCONSA S.A. en el año 2020
La presente investigación “Análisis de la sección 28 de NIIF para las PYMES, beneficios a empleados” se enfoca en analizar la importancia de dicha norma y conocer los beneficios a empleados que la empresa ARCONSA S. A ofrece a su personal de trabajo y el impacto que tienen estos en la contabilidad así mismo presentar dichos beneficios, es por ello que el objetivo principal es Analizar la sección 28 “Beneficios a empleados” de NIIF para las PYMES en la contabilidad de la empresa ARCONSA S.A en el año 2020.
Para poder desarrollarla nos hemos basado en información contenida en las Normas de Información Financiera para Pequeñas y Medianas Empresas (NIIF para las PYMES), realizando un estudio más profundo en lo relacionado con los beneficios a los empleados, además de la información contable que se fue revisando, analizando y poniendo en práctica las disposiciones legales que rigen al sector laboral de nuestro país. Se realizo un análisis a la entidad ARCONSA S. A entidad dedicada al ramo de la construcción de obras, diseño, consultoría e interventoría; teniendo una excelente referencia en el mercado por la diversidad y calidad de sus servicios.
Con este trabajo se cumple el objetivo de analizar la aplicación la sección 28 de NIIF para las PYMES, se verifica el registro de los beneficios. En el caso se expone la manera que la empresa objeto de estudio presenta los estados financieros y precisamente los beneficios a los empleados. Al final se presentan las conclusiones a las que llegamos luego de terminar nuestro trabajo, las cuales pretenden ayudar a la empresa a obtener otra visión sobre la NIIF para pyme para una mejor toma de decisiones, y de igual forma se presenta una serie de citas bibliográficas a las cuales hemos recurrido para obtener más información.
Palabras claves: Beneficios a los empleados, Pequeñas y medianas empresas, NII
Mapping NGC 7027 in New Light: CO and HCO Emission Reveal Its Photon- and X-ray-Dominated Regions
The young and well-studied planetary nebula NGC 7027 harbors significant
molecular gas that is irradiated by luminous, point-like UV (central star) and
diffuse (shocked nebular) X-ray emission. This nebula represents an excellent
subject to investigate the molecular chemistry and physical conditions within
photon- and X-ray-dominated regions (PDRs and XDRs). As yet, the exact
formation routes of CO and HCO in PN environments remain uncertain.
Here, we present 2 resolution maps of NGC 7027 in the irradiation
tracers CO and HCO, obtained with the IRAM NOEMA interferometer, along
with SMA CO and HST 2.12~m H data for context. The CO map
constitutes the first interferometric map of this molecular ion in any PN.
Comparison of CO and HCO maps reveal strikingly different emission
morphologies, as well as a systematic spatial displacement between the two
molecules; the regions of brightest HCO, found along the central waist of
the nebula, are radially offset by 1 (900 au) outside the
corresponding CO emission peaks. The CO emission furthermore precisely
traces the inner boundaries of the nebula's PDR (as delineated by near-IR H
emission), suggesting that central star UV emission drives CO formation.
The displacement of HCO radially outward with respect to CO is
indicative that dust-penetrating soft X-rays are responsible for enhancing the
HCO abundance in the surrounding molecular envelope, forming an XDR. These
interferometric CO and HCO observations of NGC 7027 thus clearly
establish the spatial distinction between the PDR and XDR formed (respectively)
by intense UV and X-ray irradiation of molecular gas.Comment: 15 pages, 7 figures, 1 tabl
Modelling the Warm H2 Infrared Emission of the Helix Nebula Cometary Knots
Molecular hydrogen emission is commonly observed in planetary nebulae. Images
taken in infrared H2 emission lines show that at least part of the molecular
emission is produced inside the ionised region. In the best-studied case, the
Helix nebula, the H2 emission is produced inside cometary knots (CKs),
comet-shaped structures believed to be clumps of dense neutral gas embedded
within the ionised gas. Most of the H2 emission of the CKs seems to be produced
in a thin layer between the ionised diffuse gas and the neutral material of the
knot, in a mini photodissociation region (PDR). However, PDR models published
so far cannot fully explain all the characteristics of the H2 emission of the
CKs. In this work, we use the photoionisation code \textsc{Aangaba} to study
the H2 emission of the CKs, particularly that produced in the interface H^+/H^0
of the knot, where a significant fraction of the H2 1-0S(1) emission seems to
be produced. Our results show that the production of molecular hydrogen in such
a region may explain several characteristics of the observed emission,
particularly the high excitation temperature of the H2 infrared lines. We find
that the temperature derived from H2 observations even of a single knot, will
depend very strongly on the observed transitions, with much higher temperatures
derived from excited levels. We also proposed that the separation between the
H_alpha and NII peak emission observed in the images of CKs may be an effect of
the distance of the knot from the star, since for knots farther from the
central star the NII line is produced closer to the border of the CK than
H_alpha.Comment: Accepted by MNRAS. The paper contains 12 pages, 9 figures, and 3
table
Ligand diversity contributes to the full activation of the jasmonate pathway in Marchantia polymorpha
In plants, jasmonate signaling regulates a wide range of processes from growth and development to defense responses and thermotolerance. Jasmonates, such as jasmonic acid (JA), (+)-7-iso-jasmonoyl-l-isoleucine (JA-Ile), 12-oxo-10,15(Z)-phytodienoic acid (OPDA), and dinor-12-oxo-10,15(Z)-phytodienoic acid (dn-OPDA), are derived from C18 (18 Carbon atoms) and C16 polyunsaturated fatty acids (PUFAs), which are found ubiquitously in the plant kingdom. Bryophytes are also rich in C20 and C22 long-chain polyunsaturated fatty acids (LCPUFAs), which are found only at low levels in some vascular plants but are abundant in organisms of other kingdoms, including animals. The existence of bioactive jasmonates derived from LCPUFAs is currently unknown. Here, we describe the identification of an OPDA-like molecule derived from a C20 fatty acid (FA) in the liverwort Marchantia polymorpha (Mp), which we term (5Z,8Z)-10-(4-oxo-5-((Z)-pent-2-en-1-yl)cyclopent-2-en-1-yl)deca-5,8-dienoic acid (C20-OPDA). This molecule accumulates upon wounding and, when applied exogenously, can activate known Coronatine Insensitive 1 (COI1) -dependent and -independent jasmonate responses. Furthermore, we identify a dn-OPDA-like molecule (Δ4-dn-OPDA) deriving from C20-OPDA and demonstrate it to be a ligand of the jasmonate coreceptor (MpCOI1-Mp Jasmonate-Zinc finger inflorescence meristem domain [MpJAZ]) in Marchantia. By analyzing mutants impaired in the production of LCPUFAs, we elucidate the major biosynthetic pathway of C20-OPDA and Δ4-dn-OPDA. Moreover, using a double mutant compromised in the production of both Δ4-dn-OPDA and dn-OPDA, we demonstrate the additive nature of these molecules in the activation of jasmonate responses. Taken together, our data identify a ligand of MpCOI1 and demonstrate LCPUFAs as a source of bioactive jasmonates that are essential to the immune response of M. polymorpha.Peer reviewe
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