The luminosity functions and stellar masses of galactic disks and spheroids

We present a method to obtain quantitative measures of galaxy morphology and apply it to a spectroscopic sample of field galaxies in order to determine the luminosity and stellar mass functions of galactic disks and spheroids. For our sample of approximately 600 galaxies, we estimate, for each galaxy, the bulge-to-disk luminosity ratio in the I band using a two-dimensional image fitting procedure. Monte Carlo simulations indicate that reliable determinations are only possible for galaxies approximately 2 mag brighter than the photometric completeness limit, leaving a sample of 90 galaxies with well-determined bulge-to-total light ratios. Using our measurements of individual disk and bulge luminosities for these 90 galaxies, we construct the luminosity functions of disks and spheroids and, using a stellar population synthesis model, we estimate the stellar mass functions of each of these components. The disk and spheroid luminosity functions are remarkably similar, although our rather small sample size precludes a detailed analysis. We do, however, find evidence in the bivariate luminosity function that spheroid-dominated galaxies occur only among the brightest spheroids, while disk-dominated galaxies span a much wider range of disk luminosities. Remarkably, the total stellar mass residing in disks and spheroids is approximately the same. For our sample (which includes galaxies brighter than M*+2, where M* is the magnitude corresponding to the characteristic luminosity), we find the ratio of stellar masses in disks and spheroids to be 1.3+/-0.2. This agrees with the earlier estimates of Schechter & Dressler but differs significantly from that of Fukugita, Hogan, & Peebles. Ongoing large photometric and redshift surveys will lead to a large increase in the number of galaxies to which our techniques can be applied and thus to an improvement in the current estimates

Possibility of Using a Satellite-Based Detector for Recording Cherenkov Light from Ultrahigh-Energy Extensive Air Showers Penetrating into the Ocean Water

We have estimated the reflected component of Cherenkov radiation, which arises in developing of an extensive air shower with primary energy of 10^20 eV over the ocean surface. It has been shown that, under conditions of the TUS experiment, a flash of the reflected Cherenkov photons at the end of the fluorescence track can be identified in showers with zenith angles up to 20 degrees.Comment: 5 pages, 3 figures. This preprint corrects errors which appeared in the English version of the article published in Bull. Rus. Acad. Sci. Phys., 2011, Vol. 75, No. 3, p. 381. The original russian text was published in Izv. RAN. Ser. Fiz., 2011, Vol. 75, No. 3, p. 41

Social, intellectual, psychological, and attractiveness judgements of lay people about patients before and after combined orthodontic-orthognathic surgical treatment

Background Facial appearance plays a significant role in the success of social interactions. There is a limited amount of evidence investigating the influence of combined orthodontic-orthognathic surgical treatment on the social judgments of lay people. Objective The aim of this study was to investigate whether changes in facial appearance following orthognathic surgery alter the social judgements made by lay people. Ethical approval Ethical approval was granted from the University of Sheffield School of Clinical Dentistry Research Ethics Committee on 17th August 2020 (Reference: 033775). Materials and methods This cross-sectional, web-based survey involved clinical photographs of six Caucasian female patients pre- and post-combined orthodontic-orthognathic treatment. Three patients had a pre-treatment class 2 skeletal pattern, and three patients had a pre-treatment class 3 skeletal pattern. Staff and students at the University of Sheffield, UK were invited to evaluate five personality traits: (i) friendliness, (ii) intelligence, (iii) attractiveness, (iv) self-confidence, and (5) trustworthiness using a 5-point Likert scale. The trait scores were summed to obtain a total social judgement score, and a paired t-test was used to compare the total scores from pre- and post-treatment images. Results There were 261 responses to the survey of which 181 (75%) were completed fully. The total social judgement scores from after treatment images were higher compared with the pre-treatment images (mean diff 1.6; P < .001) indicating more positive social judgements. The improvements in perceived social judgments were more notable for class 3 patients (mean diff 2.7) compared to class 2 patients (mean diff 0.7). Conclusion Social judgement scores were higher (more positive) from post-treatment images of patient faces than their pre-treatment images. The findings highlight the possible indirect benefits combined orthodontic-orthognathic surgical treatment may have on an individual in a social setting

On a Testing Methodology for the Mechanical Property Assessment of a New Low-Cost Titanium Alloy Derived from Synthetic Rutile

Mechanical property data of a low-cost titanium alloy derived directly from synthetic rutile is reported. A small-scale testing approach comprising consolidation via field-assisted sintering technology, followed by axisymmetric compression testing, has been designed to yield mechanical property data from small quantities of titanium alloy powder. To validate this approach and provide a benchmark, Ti-6Al-4V powder has been processed using the same methodology and compared with material property data generated from thermo-physical simulation software. Compressive yield strength and strain to failure of the synthetic rutile-derived titanium alloy were revealed to be similar to that of Ti-6Al-4V

Cross-cultural adaptation of the condition-specific malocclusion impact questionnaire for the Malayalam-speaking population—a psychometric scale validation study

Objectives The study aimed to develop a regional version of the Malocclusion Impact Questionnaire (MIQ-Malayalam) for the Malayalam-speaking Indian population. Methods The English version of MIQ was translated into Malayalam through a rigorous translation process, followed by cross-cultural adaptation. Young people aged below 18 years who were just about to start orthodontic treatment were invited to complete the Malayalam version of MIQ along with the available native version of the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ). The MIQ-Malayalam was readministered after 14 days to assess test-retest reliability. Treatment need was assessed normatively using the Dental Health Component of the Index of Orthodontic Treatment Need (IOTN-DHC) and subjectively using Aesthetic Component of the Index of Orthodontic Treatment Need (IOTN-AC). Results A total of 210 subjects completed the questionnaires (males = 47.2%; females = 52.8%; age = 12-17 years, mean = 15 years and 3 months; standard deviation = 1.9) and 50 completed repeat questionnaires. Internal consistency and test-retest reliability were high (Cronbach’s alpha = 0.952; Intra-class Correlation Coefficient = 0.93). Exploratory factor analysis derived 4 factors with exclusion of 1 item. There were significant differences (P < .05) in MIQ scores between IOTN-DHC subgroups, ensuring discriminant validity. There was a high correlation between total MIQ and total PIDAQ scores (rho = 0.884), while low between total MIQ and IOTN-AC scores (rho = 0.203). Conclusion The Malayalam version of MIQ was found to be valid and reliable and can serve as a useful condition-specific measure of oral health-related quality of life

An entangled two photon source using biexciton emission of an asymmetric quantum dot in a cavity

A semiconductor based scheme has been proposed for generating entangled photon pairs from the radiative decay of an electrically-pumped biexciton in a quantum dot. Symmetric dots produce polarisation entanglement, but experimentally-realised asymmetric dots produce photons entangled in both polarisation and frequency. In this work, we investigate the possibility of erasing the `which-path' information contained in the frequencies of the photons produced by asymmetric quantum dots to recover polarisation-entangled photons. We consider a biexciton with non-degenerate intermediate excitonic states in a leaky optical cavity with pairs of degenerate cavity modes close to the non-degenerate exciton transition frequencies. An open quantum system approach is used to compute the polarisation entanglement of the two-photon state after it escapes from the cavity, measured by the visibility of two-photon interference fringes. We explicitly relate the two-photon visibility to the degree of Bell-inequality violation, deriving a threshold at which Bell-inequality violations will be observed. Our results show that an ideal cavity will produce maximally polarisation-entangled photon pairs, and even a non-ideal cavity will produce partially entangled photon pairs capable of violating a Bell-inequality.Comment: 16 pages, 10 figures, submitted to PR

Phage Therapy of Mycobacterium Infections: Compassionate Use of Phages in 20 Patients With Drug-Resistant Mycobacterial Disease

Background: Nontuberculous Mycobacterium infections, particularly Mycobacterium abscessus, are increasingly common among patients with cystic fibrosis and chronic bronchiectatic lung diseases. Treatment is challenging due to intrinsic antibiotic resistance. Bacteriophage therapy represents a potentially novel approach. Relatively few active lytic phages are available and there is great variation in phage susceptibilities among M. abscessus isolates, requiring personalized phage identification. Methods: Mycobacterium isolates from 200 culture-positive patients with symptomatic disease were screened for phage susceptibilities. One or more lytic phages were identified for 55 isolates. Phages were administered intravenously, by aerosolization, or both to 20 patients on a compassionate use basis and patients were monitored for adverse reactions, clinical and microbiologic responses, the emergence of phage resistance, and phage neutralization in serum, sputum, or bronchoalveolar lavage fluid. Results: No adverse reactions attributed to therapy were seen in any patient regardless of the pathogen, phages administered, or the route of delivery. Favorable clinical or microbiological responses were observed in 11 patients. Neutralizing antibodies were identified in serum after initiation of phage delivery intravenously in 8 patients, potentially contributing to lack of treatment response in 4 cases, but were not consistently associated with unfavorable responses in others. Eleven patients were treated with only a single phage, and no phage resistance was observed in any of these. Conclusions: Phage treatment of Mycobacterium infections is challenging due to the limited repertoire of therapeutically useful phages, but favorable clinical outcomes in patients lacking any other treatment options support continued development of adjunctive phage therapy for some mycobacterial infections

‘We Are Not As They Think About Us’: Exploring Omani EFL Learners’ ‘Selves’ in Digital Social Spaces

This paper reports a research study of Omani EFL learners’ motivation to engage in social technologies through the medium of English, adopting Dörnyei’s (2009) L2 Motivational Self System as the main theoretical framework, whilst exploring other emergent context-sensitive motivational driving forces. The purpose of the research study was to explore identities and self-perceptions of Omani nationals using social media to learn English, an under-researched context. Reflective focused group discussions were conducted with 14 university-age students, along with individually composed language learning histories. The data of the research lends substantial support to the relevance of the L2 Motivational Self System in the Omani context, highlighting, in particular, the emerging collective national and religious identities of young Omani nationals. The paper argues for the need to deepen and broaden our understanding of the association of English social technologies and the national and religious affiliations of learners

Projected WIMP sensitivity of the LUX-ZEPLIN dark matter experiment

LUX-ZEPLIN (LZ) is a next-generation dark matter direct detection experiment that will operate 4850 feet underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. Using a two-phase xenon detector with an active mass of 7 tonnes, LZ will search primarily for low-energy interactions with weakly interacting massive particles (WIMPs), which are hypothesized to make up the dark matter in our galactic halo. In this paper, the projected WIMP sensitivity of LZ is presented based on the latest background estimates and simulations of the detector. For a 1000 live day run using a 5.6-tonne fiducial mass, LZ is projected to exclude at 90% confidence level spin-independent WIMP-nucleon cross sections above 1.4 × 10-48cm2 for a 40 GeV/c2 mass WIMP. Additionally, a 5σ discovery potential is projected, reaching cross sections below the exclusion limits of recent experiments. For spin-dependent WIMP-neutron(-proton) scattering, a sensitivity of 2.3 × 10−43 cm2 (7.1 × 10−42 cm2) for a 40 GeV/c2 mass WIMP is expected. With underground installation well underway, LZ is on track for commissioning at SURF in 2020