GMRT Low Frequency Observations of Extrasolar Planetary Systems

Extrasolar planets are expected to emit detectable low frequency radio emission. In this paper we present results from new low frequency observations of two extrasolar planetary systems (Epsilon Eridani and HD 128311) taken at 150 MHz with the Giant Metrewave Radio Telescope (GMRT). These two systems have been chosen because the stars are young (with ages < 1 Gyr) and are likely to have strong stellar winds, which will increase the expected radio flux. The planets are massive (presumably) gas giant planets in longer period orbits, and hence will not be tidally locked to their host star (as is likely to be the case for short period planets) and we would expect them to have a strong planetary dynamo and magnetic field. We do not detect either system, but are able to place tight upper limits on their low frequency radio emission, at levels comparable to the theoretical predictions for these systems. From these observations we have a 2.5sigma limit of 7.8 mJy for Epsilon Eri and 15.5 mJy for HD 128311. In addition, these upper limits also provide limits on the low frequency radio emission from the stars themselves. These results are discussed and also the prospects for the future detection of radio emission from extrasolar planets.Comment: 6 pages, 2 figures, accepted for publication in MNRA

Are We There Yet? Data Saturation in Qualitative Research

Failure to reach data saturation has an impact on the quality of the research conducted and hampers content validity. The aim of a study should include what determines when data saturation is achieved, for a small study will reach saturation more rapidly than a larger study. Data saturation is reached when there is enough information to replicate the study when the ability to obtain additional new information has been attained, and when further coding is no longer feasible. The following article critiques two qualitative studies for data saturation: Wolcott (2004) and Landau and Drori (2008). Failure to reach data saturation has a negative impact on the validity on one’s research. The intended audience is novice student researchers

Many Body Effects on the Transport Properties of Single-Molecule Devices

The conductance through a molecular device including electron-electron and electron-phonon interactions is calculated using the Numerical Renormalization Group method. At low temperatures and weak electron-phonon coupling the properties of the conductance can be explained in terms of the standard Kondo model with renormalized parameters. At large electron-phonon coupling a charge analog of the Kondo effect takes place that can be mapped into an anisotropic Kondo model. In this regime the molecule is strongly polarized by a gate voltage which leads to rectification in the current-voltage characteristics of the molecular junction.Comment: 4 pages, 4 figures, minor changes, added reference

Are We There Yet? Data Saturation in Qualitative Research

Failure to reach data saturation has an impact on the quality of the research conducted and hampers content validity. The aim of a study should include what determines when data saturation is achieved, for a small study will reach saturation more rapidly than a larger study. Data saturation is reached when there is enough information to replicate the study when the ability to obtain additional new information has been attained, and when further coding is no longer feasible. The following article critiques two qualitative studies for data saturation: Wolcott (2004) and Landau and Drori (2008). Failure to reach data saturation has a negative impact on the validity on one’s research. The intended audience is novice student researcher

“This Life is Normal for Me” : A Study of Everyday Life Experiences and Coping Strategies of Live-in Carers in Taiwan

Recruiting migrant live-in carers has become the main strategy to address the rapid increase in the number of older persons with intensive care needs in many parts of the developed world. This is also the case in northern Taiwan, where this study took place. Thirteen live-in carers from Indonesia and the Philippines were interviewed in the fall of 2019. In this article, we discuss their two main coping strategies: a) “accepting destiny”, which refers to carers accepting their life and viewing their role as a live-in carer as a job that allowed them to meet their parents’ expectations of financial support; and b) “connecting to significant others”, which is the most important way carers found motivation to keep going. However, despite their coping strategies, working as a live-in carer was experienced as a challenging and precarious lifestyle. In the conclusion, we discuss how professional social workers in collaboration with decision-makers and non-governmental organizations in Taiwan could contribute to fostering a system that would support live-in carers in ways that allow them, and the older persons they care for, to thrive.Peer reviewe

We are All Interdependent : A Study of Relationships Between Migrant Live-In Carers and Employers in Taiwan

For the past three decades, to meet the increasing need for long-term care, the Taiwanese government’s primary approach has been to import migrant care workers. In this article, we analyse qualitative interview data produced in an Indigenous community. Drawing on Kittay’s feminist dependency theory, we explore the interrelationships and collaborative efforts between live-in carers and their employers. Three types of relationships were identified: ‘unsupportive relationships’, where the live-in carer was treated as a servant; ‘supportive relationships’, where the live-in carer was treated as a care worker; and ‘semi-supportive relationships’, where the live-in carer was treated as a carer-servant. In conclusion, the article sheds light on how the live-in carer arrangement could be practised in ways that allow live-in carers and thereby their care recipients to thrive.Peer reviewe

Bayesian optimization of the PC algorithm for learning Gaussian Bayesian networks

The PC algorithm is a popular method for learning the structure of Gaussian Bayesian networks. It carries out statistical tests to determine absent edges in the network. It is hence governed by two parameters: (i) The type of test, and (ii) its significance level. These parameters are usually set to values recommended by an expert. Nevertheless, such an approach can suffer from human bias, leading to suboptimal reconstruction results. In this paper we consider a more principled approach for choosing these parameters in an automatic way. For this we optimize a reconstruction score evaluated on a set of different Gaussian Bayesian networks. This objective is expensive to evaluate and lacks a closed-form expression, which means that Bayesian optimization (BO) is a natural choice. BO methods use a model to guide the search and are hence able to exploit smoothness properties of the objective surface. We show that the parameters found by a BO method outperform those found by a random search strategy and the expert recommendation. Importantly, we have found that an often overlooked statistical test provides the best over-all reconstruction results

How to Conduct a Mini-Ethnographic Case Study: A Guide for Novice Researchers

The authors present how to construct a mini-ethnographic case study design with the benefit of an ethnographic approach bounded within a case study protocol that is more feasible for a student researcher with limited time and finances. The novice researcher should choose a design that enables one to best answer the research question. Secondly, one should choose the design that assists the researcher in reaching data saturation. Finally, the novice researcher must choose the design in which one can complete the study within a reasonable time frame with minimal cost. This is particularly important for student researchers. One can blend study designs to be able to use the best of each design that can mitigate the limitations of each as well. The authors are experienced ethnographers who currently chair dissertation committees where a student has chosen a mini-ethnographic case study design

A remarkable recurrent nova in M 31: The predicted 2014 outburst in X-rays with Swift

The M 31 nova M31N 2008-12a was recently found to be a recurrent nova (RN) with a recurrence time of about 1 year. This is by far the fastest recurrence time scale of any known RNe. Our optical monitoring programme detected the predicted 2014 outburst of M31N 2008-12a in early October. We immediately initiated an X-ray/UV monitoring campaign with Swift to study the multiwavelength evolution of the outburst. We monitored M31N 2008-12a with daily Swift observations for 20 days after discovery, covering the entire supersoft X-ray source (SSS) phase. We detected SSS emission around day six after outburst. The SSS state lasted for approximately two weeks until about day 19. M31N 2008-12a was a bright X-ray source with a high blackbody temperature. The X-ray properties of this outburst were very similar to the 2013 eruption. Combined X-ray spectra show a fast rise and decline of the effective blackbody temperature. The short-term X-ray light curve showed strong, aperiodic variability which decreased significantly after about day 14. Overall, the X-ray properties of M31N 2008-12a are consistent with the average population properties of M 31 novae. The optical and X-ray light curves can be scaled uniformly to show similar time scales as those of the Galactic RNe U Sco or RS Oph. The SSS evolution time scales and effective temperatures are consistent with a high-mass WD. We predict the next outburst of M31N 2008-12a to occur in autumn 2015.Comment: 13 pages, 7 figures, 3 tables; accepted for publication in A&