1,697 research outputs found

    Observations of an Energetically Isolated Quiet Sun Transient: Evidence of Quasi-Steady Coronal Heating

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    Increasing evidence for coronal heating contributions from cooler solar atmospheric layers, notably quiet Sun (QS) conditions, challenges standard solar atmospheric descriptions of bright transition region (TR) emission. As such, questions to the role of dynamic QS transients in contributing to the total coronal energy budget are elevated. Using observations from the {\it Atmospheric Imaging Assembly} and {\it Heliosemic Magnetic Imager} on board the {\it Solar Dynamics Observatory}, and numerical model extrapolations of coronal magnetic fields, we investigate a dynamic QS transient energetically isolated to the TR and extruding from a common footpoint shared with two heated loop arcades. A non-casual relationship is established between episodic heating of the QS transient and wide-spread magnetic field re-organization events, while evidence is found favoring a magnetic topology typical of eruptive processes. Quasi-steady interchange reconnection events are implicated as a source of the transient's visibly bright radiative signature. We consider the QS transient's temporally stable (≈\approx\,35\,min) radiative nature occurs as a result of the large-scale magnetic field geometries of the QS and/or relatively quiet nature of the magnetic photosphere, which possibly act to inhibit energetic buildup processes required to initiate a catastrophic eruption phase. This work provides insight to the QS's thermodynamic and magnetic relation to eruptive processes quasi-steadily heating a small-scale dynamic and TR transient. This work elevates arguments of non-negligible coronal heating contributions from cool atmospheric layers in QS conditions, and increases evidence for solar wind mass feeding of dynamic transients therein.Comment: 13 pages, 9 figure

    Economic basis of education

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    https://stars.library.ucf.edu/prism/1239/thumbnail.jp

    Effectiveness of diet and physical activity interventions amongst adults attending colorectal and breast cancer screening: a systematic review and meta-analysis

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    Purpose: To estimate the effectiveness of tailored physical activity and dietary interventions amongst adults attending colorectal and breast cancer screening. Methods: Five literature databases were systematically searched to identify randomised controlled trials (RCTs) of tailored physical activity and/or dietary interventions with follow-up support initiated through colorectal and breast cancer screening programmes. Outcomes included markers of body fatness, physical activity, and dietary intake. Mean differences (MDs) or standardised mean differences (SMDs) with 95% confidence intervals (CIs) were pooled using random effects models. Results: Five RCTs met the inclusion criteria encompassing a total of 722 participants. Diet and physical activity interventions led to statistically significant reductions in body mass (MD − 1.6 kg, 95% CI − 2.7 to − 0.39 kg; I2 = 81%; low quality evidence), body mass index (MD − 0.78 kg/m2, 95% CI − 1.1 to − 0.50 kg/m2; I2 = 21%; moderate quality evidence), and waist circumference (MD − 2.9 cm, 95% CI − 3.8 to − 1.91; I2 = 0%; moderate quality evidence), accompanied by an increase in physical activity (SMD 0.31, 95% CI 0.13 to 0.50; I2 = 0%; low quality evidence) and fruit and vegetable intake (SMD 0.33, 95% CI 0.01 to 0.64; I2 = 51%; low quality evidence). Conclusion: There is low quality evidence that lifestyle interventions involving follow-up support lead to modest weight loss and increased physical activity and fruit and vegetable intake. Due to the modest intervention effects, low quality of evidence and small number of studies, further rigorously designed RCTs with long-term follow-up of modifiable risk factors and embedded cost–benefit analyses are warranted (PROSPERO ref: CRD42020179960)

    Comparative Analysis of a Transition Region Bright Point with a Blinker and Coronal Bright Point Using Multiple EIS Emission Lines

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    Since their discovery twenty year ago, transition region bright points (TRBPs) have never been observed spectroscopically. Bright point properties have not been compared with similar transition region and coronal structures. In this work we have investigated three transient quiet Sun brightenings including a TRBP, a coronal BP (CBP) and a blinker. We use time-series observations of the extreme ultraviolet emission lines of a wide range of temperature T (log T = 5.3 - 6.4) from the EUV imaging spectrometer (EIS) onboard the Hinode satellite. We present the EIS temperature maps and Doppler maps, which are compared with magnetograms from the Michelson Doppler Imager (MDI) onboard the SOHO satellite. Doppler velocities of the TR BP and blinker are <,25 km s−1^{-1}, which is typical of transient TR phenomena. The Dopper velocities of the CBP were found to be < 20 km s^{-1} with exception of those measured at log T = 6.2 where a distinct bi-directional jet is observed. From an EM loci analysis we find evidence of single and double isothermal components in the TRBP and CBP, respectively. TRBP and CBP loci curves are characterized by broad distributions suggesting the existence of unresolved structure. By comparing and contrasting the physical characteristics of the events we find the BP phenomena are an indication of multi-scaled self similarity, given similarities in both their underlying magnetic field configuration and evolution in relation to EUV flux changes. In contrast, the blinker phenomena and the TRBP are sufficiently dissimilar in their observed properties as to constitute different event classes. Our work indicates that the measurement of similar characteristics across multiple event types holds class-predictive power, and is a significant step towards automated solar atmospheric multi-class classification of unresolved transient EUV sources.Comment: 38 pages, 16 figure

    Schooling habits of yellowfin tuna (Neothunnus macropterus) and skipjack (Katsuwonus pelamis) in the Eastern Pacific Ocean, as indicated by purse seine catch records, 1946-1955

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    ENGLISH: These aspects of the schooling habits of the yellowfin and skipjack tuna may be investigated by means of the logbook records of the catches of individual sets of the nets of purse-seine vessels. For both purposes it must be assumed that a set is made, in each case, on a single school of fish. The study of school sizes based on these data requires the additional assumption either that the entire school is captured or that each set captures a constant fraction of the school upon which it is made. In this paper we report on the results of such investigations based on logbook records of the purse-seine fleet. SPANISH: Estos aspectos de los hábitos gregarios de los atunes aleta amarilla y barrilete pueden ser investigados a base de los registros de bitácora en que se anotan las pescas resultantes de cada una de las operaciones con la red de encierre que realizan los barcos rederos. Para ambos propósitos hay que suponer que las operaciones se efectúan, en cada caso, en un cardumen independiente. El estudio de los tamaños de los cardúmenes o manchas, a base de estos datos, requiere una suposición adicional: que el cardumen entero es capturado o, en su defecto, que en cada operación con la red se pesca una fracción constante de la mancha objeto de la pesca. En el presente artículo damos cuenta de los resultados de dichas investigaciones basadas en los registros de bitácora que lleva la flota de embarcaciones que utilizan redes de encierre. (PDF contains 47 pages.

    Intersubjective systems theory: A fallibalist journey.

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    Intersubjective systems theory is the view that personal experience always emerges, maintains itself, and transforms in relational contexts. It is held for reasons of personal inclinations, philosophical belief, and clinical conviction. As a clinical sensibility, it primarily includes an emphasis on the emotional convictions or organizing principles that systematize experience, the personal engagement of the analyst, and the refusal to argue about reality. Key words: intersubjective; system; psychoanalysis; fallibilism; reductionism; phenomenology; experience; contextualism; hermeneutics We grace our beliefs by calling them theories. (Emmanuel Ghent) Why is intersubjective systems theory so compelling for me? First, a few words are provided about this psychoanalytic approach. This theory examines the field-two personal worlds of experience in the system they create and from which they emerge-in human development and in any form of psychoanalytic treatment. Because of this focus, intersubjectivity theory also implies a contextualist view of development and of pathogenesis, describes the emergence and modification of subjectivity (the experiential world), and defines all these processes as irreducibly relational. The observational/participatory focus is the evolving psychological field constituted by the interplay between the differently organized experiential worlds of child and caregivers, patient and analyst, and so on. Informally, it means I am always trying not only to describe experience (yours, mine, and ours) in this temporal-relational context but also to understand in what relational contexts we became the people who participate and experience as we do

    Social Media Practices of School Administrators: The Time is Now

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    The educational disruption caused by COVID-19 increased awareness of the value of organizational resiliency/sustainability and the critical need for administrators to provide timely communication among all stakeholders. If preparation programs are to provide administrators with the skills and knowledge to effectively use social media as a communication tool, we must explore the practices and perceptions of school administrators’ use of social media to communicate with stakeholders and to identify their recommended social media communication practices. The Social Media as a Tool to Effectively Communicate with Stakeholders Survey and interviews were used for data collection. Findings are focused on comfort levels, perceived effectiveness, benefits, concerns, and recommended practices reported by the school administrators who participated in the study. While, social media was found to be an effective communication tool that can promote and support positive public relations, there were noted gaps in self-efficacy and best practices of the reporting administrators. Research literature, preparation programs, and practicing administrators will equally benefit from the outcomes of this study
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