686 research outputs found
Examining the orbital decay targets KELT-9 b, KELT-16 b, and WASP-4b, and the transit-timing variations of HD 97658 b
Context. Tidal orbital decay is suspected to occur for hot Jupiters in particular, with the only observationally confirmed case of this being WASP-12b. By examining this effect, information on the properties of the host star can be obtained using the so-called stellar modified tidal quality factor Q*âČ, which describes the efficiency with which the kinetic energy of the planet is dissipated within the star. This can provide information about the interior of the star.
Aims. In this study, we aim to improve constraints on the tidal decay of the KELT-9, KELT-16, and WASP-4 systems in order to find evidence for or against the presence of tidal orbital decay. With this, we want to constrain the Q*âČ value for each star. In addition, we aim to test the existence of the transit timing variations (TTVs) in the HD 97658 system, which previously favoured a quadratic trend with increasing orbital period.
Methods. Making use of newly acquired photometric observations from CHEOPS (CHaracterising ExOplanet Satellite) and TESS (Transiting Exoplanet Survey Satellite), combined with archival transit and occultation data, we use Markov chain Monte Carlo (MCMC) algorithms to fit three models to the data, namely a constant-period model, an orbital-decay model, and an apsidal-precession model.
Results. We find that the KELT-9 system is best described by an apsidal-precession model for now, with an orbital decay trend at over 2 Ï being a possible solution as well. A Keplerian orbit model with a constant orbital period provides the best fit to the transit timings of KELT-16 b because of the scatter and scale of their error bars. The WASP-4 system is best represented by an orbital decay model at a 5 Ï significance, although apsidal precession cannot be ruled out with the present data. For HD 97658 b, using recently acquired transit observations, we find no conclusive evidence for a previously suspected strong quadratic trend in the data
The Orbit of Warm Jupiter WASP-106b is aligned with its Star
Understanding orbital obliquities, or the misalignment angles between a star's rotation axis and the orbital axis of its planets, is crucial for unraveling the mechanisms of planetary formation and migration. In this study, we present an analysis of RossiterâMcLaughlin (RM) observations of the warm Jupiter exoplanet WASP-106 b. The high-precision radial velocity measurements were made with HARPS and HARPS-N during the transit of this planet. We aim to constrain the orientation of the planet's orbit relative to its host star's rotation axis. The RM observations are analyzed using a code which models the RM anomaly together with the Keplerian orbit given several parameters in combination with a Markov chain Monte Carlo implementation. We measure the projected stellar obliquity in the WASP-106 system for the first time and find λ = (â1 ± 11)°, supporting the theory of quiescent migration through the disk
Theoretical studies of the historical development of the accounting discipline: a review and evidence
Many existing studies of the development of accounting thought have either been atheoretical or have adopted Kuhn's model of scientific growth. The limitations of this 35-year-old model are discussed. Four different general neo-Kuhnian models of scholarly knowledge development are reviewed and compared with reference to an analytical matrix. The models are found to be mutually consistent, with each focusing on a different aspect of development. A composite model is proposed. Based on a hand-crafted database, author co-citation analysis is used to map empirically the entire literature structure of the accounting discipline during two consecutive time periods, 1972â81 and 1982â90. The changing structure of the accounting literature is interpreted using the proposed composite model of scholarly knowledge development
Evaluation of Three Primary Teachersâ Approaches to Teaching Scientific Concepts in Persuasive Ways
The research set out in this paper seeks to develop pedagogical knowledge regarding how persuasive teaching approaches can be developed in primary science classrooms. To achieve this, the paper examines three case studies in which the teachers have been charged to develop and implement teaching strategies designed to persuade their children of the usefulness and validity of target scientific concepts. The analysis probes the teachersâ choice of contexts and patterns of discourse using criteria drawn from the sociocultural literature. Outcomes of the study exemplify how the teachersâ choices of learning contexts fail to emphasise the functionality of the target concepts and as a consequence scant rewards are provided for the children to participate actively in conceptually rich discourse. The final part of the paper explores how the development of what the author calls theme-specific plots, could be used to help teachers to stage teaching and learning performances which emphasise the functionality of specific explanatory models
The Future of Qualitative Research in Psychology: Accentuating the Positive.
In this paper we reflect on current trends and anticipate future prospects regarding qualitative research in Psychology. We highlight various institutional and disciplinary obstacles to qualitative research diversity, complexity and quality. At the same time, we note some causes for optimism, including publication breakthroughs and vitality within the field. The paper is structured into three main sections which consider: 1) the positioning of qualitative research within Psychology; 2) celebrating the different kinds of knowledge produced by qualitative research; and 3) implementing high quality qualitative research. In general we accentuate the positive, recognising and illustrating innovative qualitative research practices which generate new insights and propel the field forward. We conclude by emphasising the importance of research training: for qualitative research to flourish within Psychology (and beyond), students and early career researchers require more sophisticated, in-depth instruction than is currently offered
A qualitative study of professional and client perspectives on information flows and decision aid use
<p>Abstract</p> <p>Background</p> <p>This paper explores the meanings given by a diverse range of stakeholders to a decision aid aimed at helping carers of people in early to moderate stages of dementia (PWD) to select community based respite services. Decision aids aim to empower clients to share decision making with health professionals. However, the match between health professionals' perspectives on decision support needs and their clients' perspective is an important and often unstudied aspect of decision aid use.</p> <p>Methods</p> <p>A secondary analysis was undertaken of qualitative data collected as part of a larger study. The data included twelve interviews with carers of people with dementia, three interviews with expert advisors, and three focus groups with health professionals. A theoretical analysis was conducted, drawing on theories of 'positioning' and professional identity.</p> <p>Results</p> <p>Health professionals are seen to hold varying attitudes and beliefs about carers' decision support needs, and these appeared to be grounded in the professional identity of each group. These attitudes and beliefs shaped their attitudes towards decision aids, the information they believed should be offered to dementia carers, and the timing of its offering. Some groups understood carers as needing to be protected from realistic information and consequently saw a need to filter information to carer clients.</p> <p>Conclusion</p> <p>Health professionals' beliefs may cause them to restrict information flows, which can limit carers' ability to make decisions, and limit health services' ability to improve partnering and shared decision making. In an era where information is freely available to those with the resources to access it, we question whether health professionals should filter information.</p
Kinematics of the Southern Rhodope Core Complex (North Greece)
The Southern Rhodope Core Complex is a wide metamorphic dome exhumed in the northern Aegean as a result of large-scale extension
from mid-Eocene to mid-Miocene times. Its roughly triangular shape is bordered on the SW by the Jurassic and Cretaceous metamorphic
units of the Serbo-Macedonian in the Chalkidiki peninsula and on the N by the eclogite bearing gneisses of the Sideroneron
massif. The main foliation of metamorphic rocks is flat lying up to 100 km core complex width. Most rocks display a stretching
lineation trending NEĂą SW. The Kerdylion detachment zone located at the SW controlled the exhumation of the core complex from
middle Eocene to mid-Oligocene. From late Oligocene to mid-Miocene exhumation is located inside the dome and is accompanied
by the emplacement of the synkinematic plutons of Vrondou and Symvolon. Since late Miocene times, extensional basin sediments
are deposited on top of the exhumed metamorphic and plutonic rocks and controlled by steep normal faults and flat-ramp-type
structures. Evidence from Thassos Island is used to illustrate the sequence of deformation from stacking by thrusting of the
metamorphic pile to ductile extension and finally to development of extensional Plio-Pleistocene sedimentary basin. Paleomagnetic
data indicate that the core complex exhumation is controlled by a 30ĂŻÂżÂœ dextral rotation of the Chalkidiki block. Extensional
displacements are restored using a pole of rotation deduced from the curvature of stretching lineation trends at core complex
scale. It is argued that the Rhodope Core Complex has recorded at least 120 km of extension in the North Aegean, since the
last 40 My
The boomerang effect of radicalism in Discursive Psychology: A critical overview of the controversy with the Social Representations Theory.
This article provides a critical overview of the controversy between the Radical approach to Discursive Psychology (RDP) and the Social Representations Theory (SRT) and aims: a)?to show what is potentially complementary and contradictory in Discursive Psychology (DP) and the Social Representations Theory, when and why they are incompatible, and whether and how it is possible and/or desirable to integrate these two approaches. b)?to describe how the radicalism of the socio-constructionist thesis upheld by Discourse Analysis can give rise to several hard-to-solve problems, which may then be translated into a boomerang effect. In the final section, it highlights interest in dialog and âcross-fertilizationâ between researchers inspired by the less radical approach to discursive psychology and those inspired by the Social Representations Theory, pointing out the effect of methodological implications that would ensue
A pedagogy of friendship: young children's friendships and how schools can support them?
Childrenâs friendships are often neglected by teachers and researchers. This phenomenological study conducted with seven children aged five and six years explores young childrenâs perceptions of their everyday friendship experiences. This multi-method study used role play interviews, drawings and persona doll scenarios to consider childrenâs everyday experiences of friendship in school. The paper discusses the importance of socio-cultural aspects of childrenâs friendship including: imaginary friends; losing friends; protecting time and space to develop friendships and childrenâs routines and practices as they form and maintain friendships. Data and findings are discussed, leading to an original conceptual framework: a âPedagogy of Friendshipâ. This is designed to help children make meaning from their friendship experiences and also provide practitioners with the opportunity to nurture and scaffold children through their friendship experiences in schools. We suggest that there is a need to raise the profile of childrenâs friendships in early childhood education and generate an educational perspective on friendship. Finally we conclude that listening to childrenâs views of friendship indicates that the application of the framework of a âPedagogy of Friendshipâ would be beneficial to childrenâs all round learning and development.
Keywords - children's perceptions, phenomenology, friendship, key stage one, Pedagogy of Friendshi
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