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In this work we present PRyMordial: A package dedicated to efficient computations of observables in the Early Universe with the focus on the cosmological era of Big Bang Nucleosynthesis (BBN). The code offers fast and precise evaluation of BBN light-element abundances together with the effective number of relativistic degrees of freedom, including non-instantaneous decoupling effects. PRyMordial is suitable for state-of-the-art analyses in the Standard Model as well as for general investigations into New Physics active during BBN. After reviewing the physics implemented in PRyMordial, we provide a short guide on how to use the code for applications in the Standard Model and beyond. The package is written in Python, but more advanced users can optionally take advantage of the open-source community for Julia. PRyMordial is publicly available on GitHub.

The recent measurement of helium-4 from the near-infrared spectroscopy of extremely metal-poor galaxies by the Subaru Survey may point to a new puzzle in the early Universe. We exploit this new helium measurement together with the percent-level determination of primordial deuterium, to assess indications for a nonvanishing lepton asymmetry during the big bang nucleosynthesis era, paying particular attention to the role of uncertainties in the nuclear reaction network. A cutting-edge Bayesian analysis focused on the role of the newly measured extremely metal-poor galaxies, jointly with information from the cosmic microwave background, suggests the existence of a nonzero lepton asymmetry at around the 2σ level, providing a hint for cosmology beyond lambda cold dark matter. We discuss conditions for a large total lepton asymmetry to be consistently realized in the early Universe.

Systematically and explicitly addressing the teaching of speaking is an aspect of English language teaching that is often underestimated. While teachers may be presenting various speaking activities in the classroom, such activities may amount to 'doing speaking' rather than 'teaching speaking'. In this article, I argue that being a competent teacher of speaking involves understanding the 'combinatorial' nature of speaking, which includes the linguistic and discoursal features of speech, the core speaking skills that enable speakers to process and produce speech, and the communication strategies for managing and maintaining spoken interactions. The article concludes by presenting a 'teaching-speaking cycle' (Goh and Burns, 2012) that teachers can use to plan tasks and activities that explicitly address these aspects of speaking and that scaffold student learning.

An excess γ-ray signal toward the outer halo of M31 has recently been reported. Although other explanations are plausible, the possibility that it arises from dark matter (DM) is valid. In this work we interpret the excess in the framework of DM annihilation, using as our representative case WIMP DM annihilating to bottom quarks, and we perform a detailed study of the systematic uncertainty in the J-factor for the M31 field. We find that the signal favors a DM particle with a mass of ~45-72 GeV. While the mass is well constrained, the systematic uncertainty in the cross section spans 3 orders of magnitude, ranging from ~5 × 10-27-5 × 10-24 cm3 s-1. This high uncertainty is due to two main factors, namely, an uncertainty in the substructure nature and geometry of the DM halos for both M31 and the Milky Way (MW), and correspondingly, an uncertainty in the contribution to the signal from the MW's DM halo along the line of sight. However, under the conditions that the minimum subhalo mass is ≲10-6M⊙ and the actual contribution from the MW's DM halo along the line of sight is at least ~30% of its total value, we show that there is a large overlap with the DM interpretations of both the Galactic center (GC) excess and the antiproton excess, while also being compatible with the limits for the MW dwarf spheroidals. More generally, we summarize the results from numerous complementary DM searches in the energy range 10 GeV-300 GeV corresponding to the GC excess and identify a region in parameter space that still remains viable for discovery of the DM particle.

One of the current challenges facing many universities is how to support teachers in becoming researchers. This article discusses the experiences at a small private Chilean university of a new action research programme that was developed as a vehicle for helping teachers to become involved in research and write a research publication for peer-reviewed journals. We present findings from research into similar programmes about relevant factors for their success, describe the programme developed at the university with five English as a Foreign Language teachers in 2016, and discuss some reflections on this first year of the programme.

Accounts of how teacher educators begin to plan, develop, and support action research programmes for language teachers are rare, as are descriptions of the responses of the teachers who participate. This article documents and analyses the initial processes of introducing and supporting a new programme of action research for language teachers at the Universidad Chileno-Británica de Cultura (UCBC) in Santiago, Chile. To evaluate the setting up of the programme and how the teachers have perceived it in its early stages, the authors, who are the programme facilitators, have conducted a meta-study. Data include workshop and meeting recordings, workshop observation notes, a reflective account, and a teacher questionnaire. The findings indicate that the teachers value the input and collaboration provided by an initial workshop, and subsequent meetings and discussions, very highly, but that issues of time, student involvement, and academic literature are areas for further debate and development. The article ends by drawing out the broader implications for UCBC and for others wishing to initiate similar action research programmes.

Teacher agency has become a growing research interest in language education, especially at the critical juncture of widespread globalisation, when many nations including Vietnam, the context of the study, have promulgated a new language policy to respond to this transformation. However, teacher agency remains under-examined despite a small number of recent studies. In response to the paucity in the current LP literature, this qualitative case study, grounded in positioning theory, aims to explore how English teachers exercise their agency in response to the policy under prescribed contextual conditions. Data were collected from multiple sources including in-depth interviews, classroom observations, and documents. The findings showed that teachers were positioned (by the policy and their institutions) as 'mere' policy implementers who were expected to strictly follow the mandates and instructions transferred to them. Their implementation was regularly supervised and inspected by their stakeholders (including Department of Education and Training, Bureau of Education and Training, and school leaders). However, in the classroom context, the teachers attempted to adapt the policy mandates according to their interpretations, preferences, choices, and current teaching conditions. The study also proposes implications for policy makers, educational managers and school leaders to facilitate teachers' active roles in reform implementation.

In this article, we describe and model the language classroom as a complex adaptive system (see Logan & Schumann, 2005). We argue that linear, categorical descriptions of classroom processes and interactions do not sufficiently explain the complex nature of classrooms, and cannot account for how classroom change occurs (or does not occur), over time. A relational model of classrooms is proposed which focuses on the relations between different elements (physical, environmental, cognitive, social) in the classroom and on how their interaction is crucial in understanding and describing classroom action. (Contains 5 figures, 2 tables, and 1 note.)

The recruitment of "native English-speaking teachers" (NESTs) is commonly practised in English as a Foreign Language (EFL) countries. This case study focuses on NESTs teaching in the setting of Vietnamese Foreign Language Centres (FLCs) - an under-researched non-state English language education sector. The case study investigates NESTs' professional learning support needs (PLSNs) across public and private FLCs. In-depth semi-structured interviews with 12 NESTs and 11 educational leaders revealed similarities and differences in the PLSNs of NESTs in public and private FLCs. What was most striking was the mismatches in the perceptions of the PLSNs of NESTs between educational leaders and teachers. This study calls for a need to listen to NESTs' voices and to consider the PLSNs of NESTs in English language reform policies and practice. The study puts forward implications for NESTs, policymakers, and educational leaders at a time of educational change in Vietnam and similar contexts. [ABSTRACT FROM AUTHOR]