Spinorial Characterizations of Surfaces into 3-dimensional pseudo-Riemannian Space Forms

We give a spinorial characterization of isometrically immersed surfaces of arbitrary signature into 3-dimensional pseudo-Riemannian space forms. For Lorentzian surfaces, this generalizes a recent work of the first author in $\mathbb{R}^{2,1}$ to other Lorentzian space forms. We also characterize immersions of Riemannian surfaces in these spaces. From this we can deduce analogous results for timelike immersions of Lorentzian surfaces in space forms of corresponding signature, as well as for spacelike and timelike immersions of surfaces of signature (0,2), hence achieving a complete spinorial description for this class of pseudo-Riemannian immersions.Comment: 9 page

Declension Narratives, Literary Representations of Mental Disability, and New England Identity Construction: A Disabilities Studies Analysis of Northern New England Texts

This thesis employs the framework of Disabilities Theory, particularly the Social-Constructivist Model, to examine the literary figure of mental disability as a robust and reflexive trope in the construction of New England\u27s regional identity at the turn of the twentieth century through the late-twentieth century

AN EXAMINATION OF THE RELATION BETWEEN MEMORY SELF-EFFICACY AND WORKING MEMORY WITHIN THE COGNITIVE RESERVE FRAMEWORK

Dementia has been found to negatively affect multiple aspects of cognitive functioning. Despite an increasing prevalence of cognitive decline, many aging adults do not experience reduced cognitive functioning. The reason as to why some experience cognitive decline and others do not is still unclear. One leading theory thought to explain this phenomenon is the cognitive reserve theory (CR), which proposes that certain lifestyle factors (e.g., educational attainment, occupational attainment, and leisure activity participation) prolong one’s cognitive functioning and reduce the risk of cognitive decline. Memory self-efficacy (MSE), defined as one’s beliefs in their memory ability, was found to be positively related to cognitive ability, but has not been studied in concert with CR factors. Additionally, working memory, which intersects memory and executive functioning, has seldom been examined in past CR studies. The present study sought to fill these gaps by constructing a hierarchical regression to analyze if MSE explains working memory variance over and above the existing CR factors. A sample of United States adults age 55+ were recruited via MTurk. MSE (β = .42, p \u3c .001) explained variance in working memory over and above existing CR factors (i.e., educational attainment, occupational attainment, and leisure activity participation) in a hierarchical regression analysis, after controlling for age, depression, and anxiety, R2 change = .17, F(1, 186) = 40.70, p \u3c .001. These findings illustrate that MSE explains a large, unique portion of variance that is not explained by CR factors commonly thought to explain cognitive functioning

Are SAT Scores a Strong Predictor of Student Success? A Study of Education Majors, Admission Variables and the Impact of Leadership Development

This research looks at the use of SAT scores in the college admission process in regards to their ability to accurately predict the success of a student in pursuit of their undergraduate degree – specifically in the academic area of teacher preparation

Open access at a crossroads: library publishing and bibliodiversity

The open access movement has gained momentum since the Budapest Open Access Initiative (BOAI) first launched twenty years ago. Notably, there has been a drastic increase in the number of open access articles. Concerns have been raised about equality and diversity issues, however, for researchers without an affiliation (e.g. independent, unemployed and retired researchers) and researchers on the ‘scientific periphery’ who are excluded from the gold open access model. This article argues that the gold open access model is destructive to the knowledge production ecosystem by addressing the importance of bibliodiversity and the ways in which library publishing can contribute to sustainable and equitable knowledge production

Systemic inflammatory response to cardiac surgery: does female sex really protect?

Sex hormones have important interactions with the immune system and modulate the inflammatory response. In this regard, oestrogen inhibits the transcription of proinflammatory cytokines and confers tissue protection in experimental models. On the basis of this evidence, Trotter et al. in this issue of Critical Care addressed the question of whether, in children, female sex would protect against the deleterious effects of cardiac operations with cardiopulmonary bypass by providing a favourable anti-inflammatory cytokine balance. The observations made in that study suggest sex-related immunomodulation and organ protection during cardiac surgery in the paediatric population. Prospective trials conducted in large series, including sex hormone determination in neonates, infants and children with congenital cardiac defects, are necessary to test this hypothesis. The verification of sex-related intraoperative organ protection would provide new opportunities for preventing the uncontrolled systemic inflammatory response that may occur during cardiac surgery

Promoting Equity and Assuring Teaching and Learning Quality: Magisterial Lectures in a Philippine University during the COVID-19 Pandemic

When the COVID-19 pandemic forced universities to shift to online learning, one of the challenges to faculty and administrators was to provide students with high-quality, curriculum-based learning materials that could be accessed despite students’ variable levels of Internet access. Part of the Ateneo de Manila University’s response to this challenge is the production of the Magisterial Lectures, an Open Educational Resource (OER) series of video lectures by some of the University’s most respected faculty members. The goals of this paper are to describe how the production of the lectures was guided by the principles of quality and equity; to discuss the use and reach of the lectures based on YouTube analytics and a survey of Ateneo students and teachers; and to measure the impact of the lectures on students’ learning experience. We enact quality in terms of curricular alignment and high production value. Equity was achieved by making the resource available publicly, free of charge. We found that the videos reached over 350,000 viewers in 37 countries. A survey of Ateneo students and teachers, the primary beneficiaries, shows that these materials were effective educational tools. Their effectiveness is attributable to the grounding of the production in quality and equity; the teachers’ careful integration of the recordings in their lessons; and the students’ engagement with the lectures following their own learning preferences and strategies

The Incubation Effect Among Students Playing an Educational Game for Physics

The incubation effect (IE) is a problem-solving phenomenon composed of three phases: pre-incubation where one fails to solve a problem; incubation, a momentary break where time is spent away from the unsolved problem; and post-incubation where the unsolved problem is revisited and solved. Literature on IE was limited to experiments involving traditional classroom activities. This initial investigation showed evidence of IE instances in a computer-based learning environment. This paper consolidates the studies on IE among students playing an educational game called Physics Playground and presents further analysis to examine the incidence of post-incubation or the revisit to a previously unsolved problem. Prior work, which focused on predicting successful outcomes, includes a coarse-grained IE model developed with logistic regression on aggregated data and an improved model which leveraged long short-term memory (LSTM) combined with dimensionality reduction visualization technique and clustering on fine-grained data. The additional analysis which aims to understand factors that may trigger the post-incubation phase also used fine-grained data and LSTM to create a revisit model. Results show that time elapsed relative to the activity period and encountering a problem with a similar solution during incubation were possible factors in revisiting previously unsolved problems

Chaos-based TOA estimator for DS-UWB ranging systems in multiuser environment

International audienceIn this paper, we present a chaos-based decoupled multiuser ranging (DEMR) estimator for multiuser DS-UWB ranging system. In the DEMR estimator, users are decoupled by the knowledge of all the users' limited number of data bits. Then, the ranging performance of each user mainly depends on the non-cyclic autocorrelation property of the spreading code. Based on this property, we improve DEMR estimator by using the selected binary chaotic sequences instead of the Gold sequences in order to increase the system capacity and to improve the ranging accuracy. Simulations in CM1 channel show that the chaos-based DEMR estimator is quite near-far resistant and achieves a noticeable ranging accuracy even in a heavily loaded system. Compared with using Gold sequences, chaos-based DEMR not only works with more users than full load of Gold sequences but also improves the ranging accuracy especially under low SNR condition

Low complexity TOA estimator for multiuser DS-UWB system

International audienceIn this paper, we present a low complexity Time Of Arrival (TOA) estimator for direct-sequence ultra-wideband (DS-UWB) ranging system. With the assumption that TOA is the integer multiples of chip duration, our decoupled multiuser ranging (DEMR) estimator employs integrate-and-dump filter (IDF) in chip sampling rate instead of matched filter (MF) as the front-end to reduce sampling rate and to simplify the structure of estimator. This subsampling estimator is simplified substantially in dense multipath environment furthermore due to the long repetition time of DS-UWB pulse. Simulation results show that compared with other low complexity TOA estimator, DEMR estimator is not only quite near-far resistant, but also can obtain noticeable ranging performance in the fully loaded system