8383 research outputs found
Sort by
The unequal-time matter power spectrum: impact on weak lensing observables
Get PDFFrom IOP Publishing via Jisc Publications RouterHistory: received 2020-12-15, accepted 2021-06-04, ppub 2021-08, open-access 2021-08-02, epub 2021-08-02Publication status: PublishedAbstract: We investigate the impact of a common approximation of weak lensing power spectra: the use of single-epoch matter power spectra in integrals over redshift. We disentangle this from the closely connected Limber's approximation. We derive the unequal-time matter power spectrum at one-loop in standard perturbation theory and effective field theory to deal with non-linear physics. We compare these formalisms and conclude that the unequal-time power spectrum using effective field theory breaks for larger scales. As an alternative we introduce the midpoint approximation. We also provide, for the first time, a fitting function for the time evolution of the effective field theory counterterms based on the Quijote simulations. Then we compute the angular power spectrum using a range of approaches: the Limber approximation, and the geometric and midpoint approximations. We compare our results with the exact calculation at all angular scales using the unequal-time power spectrum. We use DES Y1 and LSST-like redshift distributions for our analysis. We find that the use of the Limber's approximation in weak lensing diverges from the exact calculation of the angular power spectrum on large-angle separations, ℓ < 10. Even though this deviation is of order 2% maximum for cosmic lensing, we find the biggest effect for galaxy clustering and galaxy-galaxy lensing. We show that not only is this true for upcoming galaxy surveys, but also for current data such as DES Y1. Finally, we make our pipeline and analysis publicly available as a Python package called unequalpy
The unequal-time matter power spectrum: impact on weak lensing observables
Get PDFFrom IOP Publishing via Jisc Publications RouterHistory: received 2020-12-15, accepted 2021-06-04, ppub 2021-08, open-access 2021-08-02, epub 2021-08-02Publication status: PublishedAbstract: We investigate the impact of a common approximation of weak lensing power spectra: the use of single-epoch matter power spectra in integrals over redshift. We disentangle this from the closely connected Limber's approximation. We derive the unequal-time matter power spectrum at one-loop in standard perturbation theory and effective field theory to deal with non-linear physics. We compare these formalisms and conclude that the unequal-time power spectrum using effective field theory breaks for larger scales. As an alternative we introduce the midpoint approximation. We also provide, for the first time, a fitting function for the time evolution of the effective field theory counterterms based on the Quijote simulations. Then we compute the angular power spectrum using a range of approaches: the Limber approximation, and the geometric and midpoint approximations. We compare our results with the exact calculation at all angular scales using the unequal-time power spectrum. We use DES Y1 and LSST-like redshift distributions for our analysis. We find that the use of the Limber's approximation in weak lensing diverges from the exact calculation of the angular power spectrum on large-angle separations, ℓ < 10. Even though this deviation is of order 2% maximum for cosmic lensing, we find the biggest effect for galaxy clustering and galaxy-galaxy lensing. We show that not only is this true for upcoming galaxy surveys, but also for current data such as DES Y1. Finally, we make our pipeline and analysis publicly available as a Python package called unequalpy
Understanding the Contribution of Intellectual Disability Nurses: Scoping Research
Get PDFThis is a presentation that was delivered at the IASSIDD Europe Congress 6-8 July 2021, Amsterdam, Netherlands
Ischemic Heart Disease in Nigeria: Exploring the Challenges, Current Status, and Impact of Lifestyle Interventions on Its Primary Healthcare System
Get PDFThe burden of ischemic heart disease in Nigeria calls for an evidence-based, innovative, and interdisciplinary approach towards decreasing health inequalities resulting from individual lifestyle and poor socioeconomic status in order to uphold the holistic health of individuals to achieve global sustainability and health equity. The poor diagnosis and management of ischemic heart disease in Nigeria contributes to the inadequate knowledge of its prognosis among individuals, which often results in a decreased ability to seek help and self-care. Hence, current policies aimed at altering lifestyle behaviour to minimize exposure to cardiovascular risk factors may be less suitable for Nigeria’s diverse culture. Mitigating the burden of ischemic heart disease through the equitable access to health services and respect for the autonomy and beliefs of individuals in view of achieving Universal Health Coverage (UHC) requires comprehensive measures to accommodate, as much as possible, every individual, notwithstanding their values and socioeconomic status
To What Extent do the Approaches to Leadership of General Further Education College Principals Sustain a Culture that Enhances Institutional Outcomes?
Get PDFWhat educational leadership does - not what educational leadership is. This powerful benchmark statement supports me to tell the stories of principals, middle managers and teachers within different General Further Education College settings. In this interpretive hermeneutical examination of the concepts of leadership and culture from the perspectives of three levels of General Further Education College staff I consider and interpret what they think and believe about contemporary approaches to leadership and the establishment of organisational culture through an examination of their lived experiences. I use a thematic analysis to shine a light on the experiences of three principals, three middle managers and three teachers in three institutions. The impact of the Incorporation of General Further Education Colleges since April 1993 and the subsequent marketisation and significant increase in accountability is well documented over many decades. The recognition of the dichotomy which exists in the further education sector between competing business requirements and approaches to student learning have shaped approaches to leadership and the culture required in individual colleges and the further education sector. My analysis is framed by two leadership relationship models. Nietzsche’s master and slave morality is utilised in conjunction with Graen and Uhl-Bien’s leader-member exchange theory to examine present approaches to leadership and the relationships they produce to inform macro and institutional sub-cultures to meet the competing demands on the further education sector and individual General Further Education Colleges. This framework is supported by theorists concerned with the evolution of further education leadership type and cultural development in a sector driven by market forces and government policy. The thesis highlights the impact of leadership approaches on college direction and how these concepts impact on organisational outcomes
Promoting junior school students’ anti-bullying beliefs with the CATZ Cross-age Teaching Zone intervention
Get PDFThe version of record of this article, first published in [International Journal of Bullying Prevention], is available online at Publisher’s website: http://dx.doi.org/10.1007/s42380-021-00111-9In tackling the widespread problem of bullying victimisation, researchers have acknowledged the value of focusing on changing bullying-related beliefs and using peer-based interventions. In three studies (N = 419, 237 intervention and 182 controls), we tested the effectiveness of the CATZ cross-age teaching programme by inviting small groups of 11-year-olds to incorporate information supporting positive beliefs (concerning non-physical forms of bullying, the value of disclosing being bullied to adults, and helping victims) into a lesson they devised for themselves and to deliver that to small groups of 9-year-olds. Specifically, we examined if the intervention would promote that (i) non-physical forms of bullying are unacceptable (study 1), (ii) disclosing bullying to adults and getting the right kind of help have value and importance (study 2), and (iii) victims can be assisted in safe ways (study 3). Self-reports of nine specific aspects of these beliefs were collected from CATZ tutors and age-matched controls prior to and following the intervention, and at five-week follow-up in one study, using both open and closed questions. Results indicated significant positive effects of CATZ on all nine outcome variables, with mostly medium and high effect sizes. These findings support the use of CATZ to foster positive anti-bullying beliefs, and issues related to its wider uptake are discussed
The Fall of the House of Wynnstay: The 1885 Election in East Denbighshire
Get PDFThis is the author's accepted version of an article published in ©Welsh History Review/Cylchgrawn Hanes Cymru, 2021This article discusses the 1885 election in East Denbighshire when the Williams-Wynn family of Wynnstay lost the parliamentary seat that the family had represented for over 170 years. The election took place amidst the backdrop of legislative changes to corrupt practices, the electorate, and changing constituency boundaries. Conservative and Liberal party organisation in East Denbighshire is discussed
Composite Matrices from Group Rings, Composite G-Codes and Constructions of Self-Dual Codes
Get PDFIn this work, we define composite matrices which are derived from group rings. We extend the idea of G-codes to composite G-codes. We show that these codes are ideals in a group ring, where the ring is a finite commutative Frobenius ring and G is an arbitrary finite group. We prove that the dual of a composite G-code is also a composite G-code. We also define quasi-composite G-codes. Additionally, we study generator matrices, which consist of the identity matrices and the composite matrices.
Together with the generator matrices, the well known extension method, the neighbour method and its generalization, we find extremal binary self-dual codes of length 68 with new weight enumerators for the rare parameters = 7; 8 and 9: In particular, we find 49 new such codes. Moreover, we show that the codes we find are inaccessible from
other constructions
Postcolonial pictures examining the Penguin edition book covers of Paul Theroux's travel writing through a visual social semiotic lens
Get PDFTravel literature, Paul Theroux writes, “moves from journalism to fiction, arriving […] at autobiography” (2008: 332). Perhaps because of this hybridity, travel writing is an enduring genre, and its texts are subject to fertile academic interpretation and re-interpretation. However, less attention has been given to the paratextual elements of the travel book. Book covers play a key role in establishing the nature and context of a written work. They operate as visual social semiotic forms, comprising textual and visual signifiers that stand “for an object or concept” (Moriarty, 2011: 228). The argument here is the resulting signs may encode meanings beyond the commercial purpose of the book cover. Semiotic analysis is therefore applied to the covers of Paul Theroux’s novel-length travel books. It is argued the Penguin book covers that feature on editions released over the last 40 years frequently include covert signifiers of unequal power relationships between western travellers and the
peoples and cultures they encounter
‘University is a non‐Muslim experience, you know? The experience is as good as it can be’: Satisfied settling in Muslim students’ experiences and implications for Muslim student voice
Get PDFFrom Wiley via Jisc Publications RouterHistory: received 2020-10-26, rev-recd 2021-01-09, accepted 2021-05-05, pub-electronic 2021-06-06Article version: VoRPublication status: PublishedWe report findings from a cross‐institutional investigation testing the applicability of a new concept, ‘satisfied settling’, which describes the ways in which students are unconsciously ‘settling for less’ in terms of their university experiences. The context of exploration for this article was that of Muslim students’ experiences as a critical area which has received little previous focus. Our results describe a staged cognitive process undertaken by students to subconsciously excuse institutional failures to support their religious needs by settling for lower levels of satisfaction. The ‘counter stories’ told by 19 Muslim students (via semi‐structured interviews) detail how their voices are heard or silenced around the deep importance of religious provisions in their university experiences. Satisfied settling was ultimately found to translate across institutional contexts, and the applicability of the concept is discussed in extending to other marginalised student groups
Data sources:
Access Repository Dashboard
Do you manage ChesterRep? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!