Non-stationary rotating black holes: Entropy and Hawking's radiation

We derive a class of non-stationary embedded rotating black holes and study the Hawking's radiation effects on these embedded black holes. The surface gravity, entropy and angular velocity, which are three important properties of black holes, are presented for each of these embedded black holes.Comment: 36 pages, LaTe

Scaling of the Fano effect of the in-plane Fe-As phonon and the superconducting critical temperature in Ba1−x_{1-x}Kx_{x}Fe2_{2}As2_{2}

By means of infrared spectroscopy we determine the temperature-doping phase diagram of the Fano effect for the in-plane Fe-As stretching mode in Ba$_{1-x}$K$_{x}$Fe$_{2}$As$_{2}$. The Fano parameter $1/q^2$, which is a measure of the phonon coupling to the electronic particle-hole continuum, shows a remarkable sensitivity to the magnetic/structural orderings at low temperatures. More strikingly, at elevated temperatures in the paramagnetic/tetragonal state we find a linear correlation between $1/q^2$ and the superconducting critical temperature $T_c$. Based on theoretical calculations and symmetry considerations, we identify the relevant interband transitions that are coupled to the Fe-As mode. In particular, we show that a sizable $xy$ orbital component at the Fermi level is fundamental for the Fano effect and possibly also for the superconducting pairing.Comment: Supplemental materials are available upon reques

Psychology students’ perception of and engagement with feedback as a function of year of study

Undergraduate students’ perception of feedback and level of engagement with the feedback they receive have gained increasing attention in the educational literature recently to identify areas which require educators’ attention. However, research in this area has generally been based on limited self-selecting samples, and has not considered how students’ relationship with feedback may alter depending on their year of study. To address this, a survey measuring students’ views and practices regarding feedback was completed at a higher education institution by 447 first-, second- and third-year psychology students, representing 77% of the cohort. Findings revealed that third years responded more negatively in both areas than their first- and second-year counterparts, whose ratings on these aspects themselves were far from optimal. These findings highlight the need for early interventions to improve students’ perception of and engagement with feedback in the earlier years, and to prevent the recorded deterioration later on in the degree course

Inflating Lorentzian Wormholes

It has been speculated that Lorentzian wormholes of the Morris- Thorne type might be allowed by the laws of physics at submicroscopic, e.g. Planck, scales and that a sufficiently advanced civilization might be able to enlarge them to classical size. The purpose of this paper is to explore the possibility that inflation might provide a natural mechanism for the enlargement of such wormholes to macroscopic size. A new classical metric is presented for a Lorentzian wormhole which is imbedded in a flat deSitter space. It is shown that the throat and proper length of the wormhole inflate. The resulting properties and stress-energy tensor associated with this metric are discussed.Comment: 24 pg

Observer agreement for small bowel ultrasound in Crohn's disease: results from the METRIC trial

PURPOSE: To prospectively evaluate interobserver agreement for small bowel ultrasound (SBUS) in newly diagnosed and relapsing Crohn's disease. METHODS: A subset of patients recruited to a prospective trial comparing the diagnostic accuracy of MR enterography and SBUS underwent a second SBUS performed by one of a pool of six practitioners, who recorded the presence, activity and location of small bowel and colonic disease. Detailed segmental mural and extra-mural observations were also scored. Interobserver variability was expressed as percentage agreement with a construct reference standard, split by patient cohort, grouping disease as present or absent. Prevalence adjusted bias adjusted kappa (PABAK), and simple percentage agreement between practitioners, irrespective of the reference standard, were calculated. RESULTS: Thirty-eight patients (11 new diagnosis, 27 relapse) were recruited from two sites. Overall percentage agreement for small bowel disease presence against the consensus reference was 82% (52-95% (95%CI)), kappa coefficient (κ) 0.64, (substantial agreement) for new diagnosis and 81%, κ 0.63 (substantial agreement) for the relapsing cohort. Agreement for colonic disease presence was 64%, κ 0.27 (fair agreement) in new diagnosis and 78%,κ 0.56 (moderate agreement) in the relapsing cohort. Simple agreement between practitioners was 84% and 87% for small bowel and colonic disease presence respectively. Practitioners agreed on small bowel disease activity in 24/27 (89%) where both identified disease. Kappa agreement for detailed mural observations ranged from κ 0.00 to 1.00. CONCLUSION: There is substantial practitioner agreement for small bowel disease presence in newly diagnosed and relapsing CD patients, supporting wider dissemination of enteric US

Being a Self-Employed Older Woman: From Discrimination to Activism

This article presents an autobiographical account of an older woman’s lived experience of self-employment. Little is known about women who experience ongoing self-employment into their 50s and beyond. Shoshanna’s personal narrative describes her experiences and the challenges she has faced as she reflects upon her attempts to grow and sustain her business and the implications of ageism and gender inequality in laying a claim to entrepreneurship. The narrative proceeds to reflect on her activist work, as it is constructed through the creation of a social enterprise to support older people. Shoshanna’s narrative provides valuable insights into the intersection of age and gender in self-employment moving from discrimination to active support

The motivational antecedents of the development of mental toughness: a self-determination theory perspective

Mental toughness is a topic that has received growing attention in psychological literature over the past decade. Although some researchers have attempted to understand how mental toughness is developed, little effort has been made to integrate an understanding of mental toughness development with established psychological theory and research. The aim of our review is to demonstrate the utility of theory and research on motivation for understanding mental toughness and its development. In particular, we propose that self-determination theory provides a sound basis for understanding the motivational antecedents of mental toughness. To achieve our aim, we consider concepts that bridge mental toughness and self-determination theory literature, namely striving, surviving, and thriving. We conclude our review with suggestions for future lines of empirical enquiry that could be pursued to further test our propositions

Towards a framework for analysis of eye-tracking studies in the three dimensional environment: a study of visual search by experienced readers of endoluminal CT colonography.

Objective: Eye tracking in three dimensions is novel, but established descriptors derived from two-dimensional (2D) studies are not transferable. We aimed to develop metrics suitable for statistical comparison of eye-tracking data obtained from readers of three-dimensional (3D) “virtual” medical imaging, using CT colonography (CTC) as a typical example. Methods: Ten experienced radiologists were eye tracked while observing eight 3D endoluminal CTC videos. Sub-sequently, we developed metrics that described their visual search patterns based on concepts derived from 2D gaze studies. Statistical methods were developed to allow analysis of the metrics. Results: Eye tracking was possible for all readers. Visual dwell on the moving region of interest (ROI) was defined as pursuit of the moving object across multiple frames. Using this concept of pursuit, five categories of metrics were defined that allowed characterization of reader gaze behaviour. These were time to first pursuit, identi-fication and assessment time, pursuit duration, ROI size and pursuit frequency. Additional subcategories allowed us to further characterize visual search between readers in the test population. Conclusion: We propose metrics for the characterization of visual search of 3D moving medical images. These metrics can be used to compare readers’ visual search patterns and provide a reproducible framework for the analysis of gaze tracking in the 3D environment. Advances in knowledge: This article describes a novel set of metrics that can be used to describe gaze behaviour when eye tracking readers during interpretation of 3D medical images. These metrics build on those established for 2D eye tracking and are applicable to increasingly common 3D medical image displays

The Doing and Undoing of the “Autistic Child”: Cutting Together and Apart Interview-based Empirical Materials

This article discusses how posthuman and new materialist theories afford us opportunities to rethink the production of the “autistic child,” drawing on a qualitative research project on parenthood in the context of childhood disability in Italy. We will put some Baradian’s key concepts (intra-action, agential cut and cutting together-apart) to work in glancing at the complexities we keep encountering when a mother, Arianna, describes her relationship with her daughter Laura. The aim of this article is twofold: first, to methodologically re-turn the production of the “autistic child,” and second, to rethink and unsettle the dichotomies that constitute some children as “disabled human beings,” abnormal, and undesirable

The accuracy of diagnostic indicators for coeliac disease: A systematic review and meta-analysis

Background: The prevalence of coeliac disease (CD) is around 1%, but diagnosis is challenged by varied presentation and non-specific symptoms and signs. This study aimed to identify diagnostic indicators that may help identify patients at a higher risk of CD in whom further testing is warranted. // Methods: International guidance for systematic review methods were followed and the review was registered at PROSPERO (CRD42020170766). Six databases were searched until April 2021. Studies investigating diagnostic indicators, such as symptoms or risk conditions, in people with and without CD were eligible for inclusion. Risk of bias was assessed using the QUADAS-2 tool. Summary sensitivity, specificity, and positive predictive values were estimated for each diagnostic indicator by fitting bivariate random effects meta-analyses. // Findings: 191 studies reporting on 26 diagnostic indicators were included in the meta-analyses. We found large variation in diagnostic accuracy estimates between studies and most studies were at high risk of bias. We found strong evidence that people with dermatitis herpetiformis, migraine, family history of CD, HLA DQ2/8 risk genotype, anaemia, type 1 diabetes, osteoporosis, or chronic liver disease are more likely than the general population to have CD. Symptoms, psoriasis, epilepsy, inflammatory bowel disease, systemic lupus erythematosus, fractures, type 2 diabetes, and multiple sclerosis showed poor diagnostic ability. A sensitivity analysis revealed a 3-fold higher risk of CD in first-degree relatives of CD patients. // Conclusions: Targeted testing of individuals with dermatitis herpetiformis, migraine, family history of CD, HLA DQ2/8 risk genotype, anaemia, type 1 diabetes, osteoporosis, or chronic liver disease could improve case-finding for CD, therefore expediting appropriate treatment and reducing adverse consequences. Migraine and chronic liver disease are not yet included as a risk factor in all CD guidelines, but it may be appropriate for these to be added. Future research should establish the diagnostic value of combining indicators