The chemical composition of carbon stars: The R-type stars

The aim of this work is to shed some light on the problem of the formation of carbon stars of R-type from a detailed study of their chemical composition. We use high-resolution and high signal-to-noise optical spectra of 23 R-type stars selected from the Hipparcos catalogue. The chemical analysis is made using spectral synthesis in LTE and state-of-the-art carbon-rich spherical model atmospheres. We derive their CNO content (including the carbon isotopic ratio), average metallicity, lithium, and light (Sr, Y, Zr) and heavy (Ba, La, Nd, Sm) s-element abundances. The observed properties of the stars (galactic distribution, kinematics, binarity, photometry and luminosity) are also discussed. Our analysis shows that late-R stars are carbon stars with identical chemical and observational characteristics than the normal (N-type) AGB carbon stars. We confirm the results of the sole previous abundance analysis of early-R stars by Dominy (1984, ApJS, 55, 27), namely: they are carbon stars with near solar metallicity showing enhanced nitrogen, low carbon isotopic ratios and no s-element enhancements. In addition, we have found that early-R stars have Li abundances larger than expected for post RGB tip giants. We also find that a significant number (aprox. 40 %) of the early-R stars in our sample are wrongly classified, being probably classical CH stars and normal K giants. In consequence, we suggest that the number of true R stars is considerably lower than previously believed. We briefly discuss the different scenarios proposed for the formation of early-R stars. The mixing of carbon during an anomalous He-flash is favoured, although no physical mechanism able to trigger that mixing has been found yet. The origin of these stars still remains a mystery.Comment: 15 pages, 8 figures, accepted for publication in Astronomy and Astrophysic

Factors that affect quality of work life of the millennials linked to the commercial sector in Colombia

The present investigation has two aims: (1) to empirically examine the factors that affect QWL among the millennials working in the commercial sector in Colombia and (2) to investigate the role of a set of individual differences as moderators (for example, gender, educational level and type of contract) in a complete QWL model, based on the methodology of (Tarhini, Hone, & Liu, 2014). The instrument used was the Work Quality of Life Tool (Wage and Subjective Conditions) which has been validated in the previous studies. The total of 1,163 surveys were conducted with workers from the commercial sector in Colombia who belong to the generation Y or the millennial generation, that is, born between 1981 and 2000. The results show that training, promotion, wages and the relationship of the individual with their work directly and positively affect the quality of work life in the study sample. We conduct a confirmatory factor analysis based on structural equations, revealing that the majority of the hypothesis associated with gender, educational level and type of contract were supported. This study serves to support the establishment of programs, projects and management plans to generate adequate use of the talents and skills of the millennials and thus create challenging and satisfactory jobs that increase organizational productivity. © 2021, Centre of Sociological Research. All rights reserved

Teletrabajo y desempeño laboral de los trabajadores de la Oficina de Abastecimiento del Ministerio de Desarrollo e Inclusión Social –Lima 2021

La presente investigación tuvo por objetivo general determinar la relación entre teletrabajo y desempeño laboral de los trabajadores de la Oficina de Abastecimiento del Ministerio de Desarrollo e Inclusión Social – Lima 2021. Para tal efecto, se tuvo en cuenta una metodología de enfoque cuantitativo, de alcance correlacional y de diseño no experimental. En consecuencia, para obtener la información se aplicó una encuesta mediante un cuestionario de preguntas con alternativa de Likert, en una población y muestra de 52 trabajadores. Los resultados reportados indicaron que la relación entre teletrabajo y desempeño laboral fue de 0.335 y p-valor de 0.015. Asimismo, se encontró relación entre teletrabajo con objetivos de la evaluación del desempeño y tipos de evaluación; no encontrándose relación con conductas del desempeño laboral. Se concluyó que existe relación significativa entre teletrabajo y desempeño laboral de los trabajadores de la Oficina de Abastecimiento del MIDIS- Lima 2021

Gastric adenocarcinoma microRNA profiles in fixed tissue and in plasma reveal cancer-associated and Epstein-Barr virus-related expression patterns

MicroRNA expression in formalin fixed paraffin embedded tissue (FFPE) or plasma may add value for cancer management

Evolution of Angiogenic Factors in Pregnant Patients with Breast Cancer Treated with Chemotherapy

Factors angiogènics; Quimioteràpia; EmbaràsFactores angiogénicos; Quimioterapia; EmbarazoAngiogenic factors; Chemotherapy; PregnancyHigh prevalence of placental-derived complications, such as preeclampsia and intrauterine growth restriction, has been reported in women with breast cancer (BC) treated with chemotherapy during pregnancy (PBC-CHT). Aim: To ascertain whether PBC-CHT is associated with an imbalance of angiogenic factors, surrogate markers for placental insufficiency, that could explain perinatal outcomes. Methods: Prospective study between 2012 and 2016 in a single institution. Soluble fms-like tyrosine kinase (sFlt-1), placental growth factor (PlGF), and soluble endoglin (sEng) in maternal blood were assessed throughout pregnancy in 12 women with BC and 215 controls. Results: Cancer patients were treated with doxorubicin-based regimes and with taxanes. Ten PBC-CHT (83%) developed obstetrical complications. At the end of the third trimester, significantly higher levels of sFlt-1; sFlt-1/PGF ratio, and sEng levels were observed in BC women as compared to controls. Moreover; there was a significant correlation between plasma levels of sFlt-1 and the number of chemotherapy cycles administered. Besides, more chemotherapy cycles correlated with lower birthweight and head circumference at birth. Conclusions: Women with BC treated during pregnancy showed an antiangiogenic state compatible with placental insufficiency. Angiogenic factors could be useful in the clinical obstetric management of these patients; although further studies will be required to guide clinical decision-making.This study was funded by the Spanish Research Project in Health funded by ISCIII, the state plan for scientific and technical research and innovation 2015–2018, and European Regional Development Fund (ERDF), ref. PI15/02252. This study was also supported in part by RETICS ‘Maternal and Child Health and Development Network’ (SAMID Network), funded by the PN I + D + i 2008–2016 (Spain), ISCIII-Sub-Directorate General for Research Assessment and Promotion, and the European Regional Development Fund (ERDF), ref. RD12/0026 and RD16/0022. O.S. was supported by SAMID Network (RD12/0026/0016 and RD16/0022/0015) and S.M. was supported by “Paseico de la mama”

Polarization-tuneable excitonic spectral features in the optoelectronic response of atomically thin ReS2

The low crystal symmetry of rhenium disulphide (ReS2) leads to the emergence of dichroic optical and optoelectronic response, absent in other layered transition metal dichalcogenides, which could be exploited for device applications requiring polarization resolution. To date, spectroscopy studies on the optical response of ReS2 have relied almost exclusively in characterization techniques involving optical detection, such as photoluminescence, absorbance, or reflectance spectroscopy. However, to realize the full potential of this material, it is necessary to develop knowledge on its optoelectronic response with spectral resolution. In this work, we study the polarization-dependent photocurrent spectra of few-layer ReS2 photodetectors, both in room conditions and at cryogenic temperature. Our spectral measurements reveal two main exciton lines at energies matching those reported for optical spectroscopy measurements, as well as their excited states. Moreover, we also observe an additional exciton-like spectral feature with a photoresponse intensity comparable to the two main exciton lines. We attribute this feature, not observed in earlier photoluminescence measurements, to a non-radiative exciton transition. The intensities of the three main exciton features, as well as their excited states, modulate with linear polarization of light, each one acquiring maximal strength at a different polarization angle. We have performed first-principles exciton calculations employing the Bethe-Salpeter formalism, which corroborate our experimental findings. Our results bring new perspectives for the development of ReS2-based nanodevices

Studying and supporting collaborative care processes

Paper presented at the Human Factors & Ergonomics Society (HFES 2005), June 13, 2005.In patient care today, teams of practitioners from various disciplines must coordinate their efforts in order to deliver care successfully. Frontline nurses and physicians must interact with social workers, therapists, physician assistants, nurse practitioners, and others to develop and carry out coordinated plans of care. Also, clinical team members must communicate with patients and their families in language that can be understood and acted upon. In support of these goals, JCAHO standards require patient care to be planned and provided in an interdisciplinary, collaborative manner. As hospital units develop processes for collaborative care in complex environments such as post-surgery and critical care units, it is important to understand what constitutes success for these processes and how they can be enabled and supported. This report documents a series of field visits and simulations designed to observe, videotape, and interview collaborative care team members, patients, and family members engaged in varying forms of collaborative practice. This ongoing research is being conducted by a multi-disciplinary team of medical and social scientists with a shared goal of studying and supporting collaborative care processes

Communications analysis of the concord collaborative care model

Presentation given at the 2005 Safety Across High-Consequence Industries Conference ,SAHI 2005, Saint Louis, MO. Retrieved July 18, 2007 from http://www.cis.drexel.edu/faculty/gerry/pub/sahi2005.pdf