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Signatures of feedback in the spectacular extended emission region of NGC 5972
(2023) Harvey, Thomas; Maksym, W. Peter; Keel, William; Koss, Michael; Bennert, Vardha N.; Chojnowski, S. Drew; Treister, Ezequiel; Finlez, Carolina; Lintott, Chris J.; Moiseev, Alexei; Simmons, Brooke D.; Sartori, Lia F.; Urry, Megan
We present Chandra X-ray Observatory observations and Space Telescope Imaging Spectrograph spectra of NGC 5972, one of the 19 ‘Voorwerpjes’ galaxies. This galaxy contains an extended emission-line region (EELR) and an arcsecond scale nuclear bubble. NGC 5972 is a faded active galactic nucleus (AGN), with EELR luminosity suggesting a 2.1 dex decrease in Lbol in the last ∼5 × 104 yr. We investigate the role of AGN feedback in exciting the EELR and bubble given the long-term variability and potential accretion state changes. We detect broad-band (0.3–8 keV) X-ray emission in the near-nuclear regions, coincident with the [O III] bubble, as well as diffuse soft X-ray emission coincident with the EELR. The soft nuclear (0.5–1.5 keV) emission is spatially extended and the spectra are consistent with two APEC thermal populations (∼0.80 and ∼0.10 keV). We find a bubble age >2.2 Myr, suggesting formation before the current variability. We find evidence for efficient feedback with Pkin/Lbol ∼ 0.8 per cent, which may be overestimated given the recent Lbol variation. [O III] kinematics show a 300 km s−1 high-ionization velocity consistent with disturbed rotation or potentially the line-of-sight component of a ∼780 km s−1 thermal X-ray outflow capable of driving strong shocks to photoionize the precursor material. We explore possibilities to explain the overall jet, radio lobe and EELR misalignment including evidence for a double supermassive black hole which could support a complex misaligned system.
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Effects of the First Spontaneous Breathing Trial in Children With Tracheostomy and Long-Term Mechanical Ventilation
(NLM (Medline), 2023) Villarroel-Silva, Gregory; Jalil Contreras, Yorschua Frederick; Moya-Gallardo, E.; Oyarzun Aguirre, Ignacio Javier; Moscoso Altamira, Gonzalo Andrés; Astudillo Maggio, Claudia Ester; Damiani Rebolledo, Luis Felipe
Copyright © 2023 by Daedalus Enterprises.BACKGROUND: Weaning and liberation from mechanical ventilation in pediatric patients with tracheostomy and long-term mechanical ventilation constitute a challenging process due to diagnosis heterogeneity and significant variability in the clinical condition. We aimed to evaluate the physiological response during the first attempt of a spontaneous breathing trial (SBT) and to compare variables in subjects who failed or passed the SBT. METHODS: This was a prospective observational study in tracheostomized children with long-term mechanical ventilation admitted to the Hospital Josefina Martinez, Santiago, Chile, between 2014-2020. Cardiorespiratory variables such as breathing pattern, use of accessory respiratory muscles, heart rate, breathing frequency, and oxygen saturation were registered at baseline and throughout a 2-h SBT with or without positive pressure depending on an SBT protocol. Comparison of demographic and ventilatory variables between groups (SBT failure and success) was performed. RESULTS: A total of 48 subjects were analyzed (median [IQR] age of 20.5 [17.0-35.0] months, 60% male). Chronic lung disease was the primary diagnosis in 60% of subjects. Eleven (23%) total subjects failed the SBT (< 2 h), with an average failure time of 69 ± 29 min. Subjects who failed the SBT had a significantly higher breathing frequency, heart rate, and end-tidal CO2 than subjects who succeeded (P < .001). In addition, subjects who failed the SBT had significantly shorter duration of mechanical ventilation before the SBT, higher proportion unassisted SBT, and higher rate of deviation SBT protocol in comparison with subjects who succeeded. CONCLUSIONS: Conducting an SBT to evaluate the tolerance and cardiorespiratory response in tracheostomized children with long-term mechanical ventilation is feasible. Time on mechanical ventilation before the first attempt and type of SBT (with or without positive pressure) could be associated with SBT failure.
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The Biblical Hermeneutics of Noetus of Smyrna
(2023) Morales, Xavier
Noetus of Smyrna, who probably lived at the end of the 2d century, was proclaimed the father of modalism by the history of dogmas. His character, eclipsed by his successors to the role of the main representative of modalism (Sabellius or Marcellus of Ancyra), remains enigmatic. The two main documentary sources, Against Noetus (Contra Noetum) and Refutation of All Heresies (Refutatio omnium haeresium), give a discordant presentation of him: defender of a naïve interpretation of biblical monotheism or inventor of a Christian heracliteism? This article, after a brief historical introduction, studies the scriptural hermeneutics of the Smyrniot to show that Noetus is not a simplistic exegete or a narrow-minded theologian. His theology of divine identity, which it is wrong to call modalism, is based on an intelligent analysis of the Scriptures.
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Uso de modelo alométrico para la evaluación del almacenamiento de carbono en uva de mesa (Vitis vinífera)
María Consuelo Arellano Salas; Arellano, Eduardo
Estimar el contenido de carbono en la biomasa de cultivos perennes como el de uva de mesa (Vitis vinifera) es relevante en el contexto de la sustentabilidad agrícola ya que permite comprender su potencial de secuestrar carbono. Este estudio evalúa el contenido de biomasa de 20 individuos de vid de mesa en un cultivo ubicado en la Región de O’Higgins. El objetivo fue generar un modelo de biomasa perenne del cultivo con énfasis en el contenido de carbono. Los objetivos específicos fueron: desarrollar metodologías para la estimación de biomasa aérea y radicular de las plantas mediante método destructivo; formular modelos de estimación de biomasa a partir de variables dendrométricas y de relaciones alométricas; y determinar el contenido de carbono a partir del modelo de biomasa propuesto. La estimación de biomasa total fue a partir de un modelo de biomasa aérea y radicular y arrojó valores de carbono (ton/ha) de 18,2 (15,6 de biomasa aérea y 2,6 de radicular), con un promedio de carbono por individuo del 54%. Estos valores son mayores a los reportados por otros estudios, posiblemente por factores como la variedad, la edad y el sistema de conducción del cultivo. Se concluye que las vides de mesa son cultivos perennes con un alto potencial de almacenar carbono en sus tejidos leñosos. Este trabajo es un aporte a la viticultura nacional por proponer el primer modelo para la estimación de carbono en la biomasa de cultivos de uva de mesa en Chile.
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Foreign Language Enjoyment, Linguistic Self-confidence, and the Oral Production of Past-tense Irregular Verbs in Online Interaction
(2023) Núñez Carmona, Melissa Belén; Ramay, Allison; Pontificia Universidad Católica de Chile. Facultad de Letras
The present study investigated the acquisition of the irregular past tense in an online setting through a positive psychology lens. Due to the learning and contextual needs of the participant, the pedagogical efforts of this research project were put on her linguistic as well as sociocultural development. The constructs involved were foreign language enjoyment (FLE) and linguistic self-confidence (LSC), which have been studied in relation to other sociolinguistic variables inside the classroom. The current study aimed to a) analyze an EFL student’s foreign language enjoyment while speaking to other English-language users through a video chat online platform and b) analyze the role of foreign language enjoyment in relationship to the oral production of irregular past tense verbs in online conversations. To achieve these objectives, a mixed-methods design was used in the context of a case study. Data was obtained from pre- and post-intervention interviews with the student, in which her FLE and LSC levels were measured as well as her irregular past tense performance, and oral interactions with other English speakers from around the globe through the HelloTalk language-learning app. It was found that the factors of the participant’s FLE and LSC were positively influenced by the intervention and that the accurate production of irregular past-tense forms is related to a learner’s LSC levels. This piece of research sheds light on ways of boosting L2 learners’ FLE and, more specifically, their LSC by using social-media-like language-learning tools for oral practice and real-life interaction.