New Colour-Mass to Light Relations: the role of the Asymptotic Giant Branch phase and of interstellar dust

Colour-M/L (mass-to-light) relations are a popular recipe to derive stellar mass in external galaxies. Stellar mass estimates often rely on near infrared (NIR) photometry, considered an optimal tracer since it is little affected by dust and by the "frosting" effect of recent star formation episodes. However, recent literature has highlighted that theoretical estimates of the NIR M/L ratio strongly depend on the modelling of the Asymptotic Giant Branch (AGB) phase. We use the latest Padova isochrones, with detailed modelling of the Thermally Pulsing AGB phase, to update theoretical colour-M/L relations in the optical and NIR and discuss the consequences for the estimated stellar masses in external galaxies. We also discuss the effect of attenuation by interstellar dust on colour-M/L relations in the statistical case of large galaxy samples.Comment: 17 pages, 13 figures. MNRAS in pres

Philadelphia's Changing Schools and What Parents Want From Them

Based on a survey, examines parents' expectations from and perceptions of school reforms, performance, and options among district-run, charter, private, and Catholic schools; priorities; and challenges by race/ethnicity, age, and income

What are the determinants of quality of life in people with cervical dystonia?

Background: Little is known about the quality of life in patients with cervical dystonia, although pain and depression are relatively common. Objective: To test the hypothesis that an individual’s ability to cope with the disease will modify the association of intrinsic, extrinsic, and disease related factors with quality of life. Methods: Patients with cervical dystonia diagnosed by a movement disorder specialist were recruited from seven European countries. Data on quality of life (SF-36), measures of coping, and intrinsic, extrinsic, and disease related factors were collected by a self completed postal questionnaire. Results: 289 patients (101 men and 188 women), mean age 55 years, completed the questionnaire. Both physical and mental quality of life scores were predicted by self esteem and self deprecation, educational level, employment status, social support, response to botulinum toxin, disease severity, social participation, stigma, acceptance of illness, anxiety, and depression. In multivariable analyses, the strongest predictors were anxiety and depression. Severe depression was associated with a 19.1 point decrement in the physical summary score (95% confidence interval, -31.7 to -6.6; p = 0.003); however, disease duration and severity remained predictors. Conclusions: Care for patients with cervical dystonia must not only focus on reducing the severity of the dystonia but also on the psychological wellbeing of the patient. Interventions aimed at treating depression or anxiety, especially of a cognitive nature, may have a large impact on improving quality of life

Low-temperature chemistry using the R-matrix method

Techniques for producing cold and ultracold molecules are enabling the study of chemical reactions and scattering at the quantum scattering limit, with only a few partial waves contributing to the incident channel, leading to the observation and even full control of state-to-state collisions in this regime. A new R-matrix formalism is presented for tackling problems involving low- and ultra-low energy collisions. This general formalism is particularly appropriate for slow collisions occurring on potential energy surfaces with deep wells. The many resonance states make such systems hard to treat theoretically but offer the best prospects for novel physics: resonances are already being widely used to control diatomic systems and should provide the route to steering ultracold reactions. Our R-matrix-based formalism builds on the progress made in variational calculations of molecular spectra by using these methods to provide wavefunctions for the whole system at short internuclear distances, (a regime known as the inner region). These wavefunctions are used to construct collision energy-dependent R-matrices which can then be propagated to give cross sections at each collision energy. The method is formulated for ultracold collision systems with differing numbers of atoms.Comment: Presented at Faraday Discussion on the Theory of Chemical Reactions Published in Faraday Discussion

Pericyte, Neural Crest And Adipocyte Differentiation Markers: Support For A Novel Hypothesis For The Origin Of Hemangiomas

Introduction: Hemangiomas are the most common benign tumor of infancy. They are unique in that their behavioral course is well-described with a microvascular proliferative phase, quiescent phase and regressive fatty involuting phase. First, it is posited in this work that the cell of origin will have angiogenic and adipogenic properties, like the pericyte. Second, the predilection of the lesion to areas of embryologic fusions in the head and neck indicate that the neural crest may be involved. Previous research focused on the angiogenic characteristics of proliferating hemangiomas, this work is novel in that it investigates markers involved in adipogenesis. This study explores the possibility that hemangiomas are pericyte-like stem cell tumors, derived from the neural crest, capable of adipocyte differentiation. Methods: Markers for pericytes, stem cells and neural crest cells as well as adipocyte differentiation were analyzed using using immunohistochemistry, immunofluorescence and quantitative RT-PCR. These markers included: NG2, SMA, calponin, CD90(Thy1), GLUT1, dlk (pericytes); Pauf5 (Oct4), Nanog, Sox2, Sox9, Sox10, c-myc (stem cells); Nestin, Sox10, NGFR (p75), NG2 (neural crest cells) and C/EBPá, C/EBPâ, C/EBPä, PPARã, dlk, RXR, SREBF, Sox9, and Krûppel-like factors (KLF2, KLF4, KLF5, KLF6, KLF15) (adipocyte differentiation markers). Immunohistochemistry and immunofluorescence was done on formalin-fixed, paraffin-embedded archival tissue. qRT-PCR was performed on 15 hemangioma specimens (5 proliferating, 3 early quiescent, 4 late quiescent, and 5 involuting) and compared to Human Dermal Microvascular Endothlial Cells (HDMEC) utilizing the delta-delta Ct method of analysis. Hemangioma phase was determined by clinical notes. To compare hemangioma phases, a one-way ANOVA was done with a Tukey HSD post hoc analysis. Results: Immunohistochemistry identified these markers in the periluminal structures within the hemangiomas: GLUT1, dlk, SMA, and Nestin. Immunofluorescence identified these markers in a confirmatory pattern: GLUT1, dlk, SMA, Nestin, Sox2, Calponin and NG2. The qRTPCR analysis revealed that the relative expression of all (pericyte, stem cell, neural crest and adipocyte differentiation) analyzed markers was greater than that of the HDMEC control. Significant differences were found between the hemangioma phases for Sox9, C/EBPâ and KLF2. Conclusion: The work presented in this thesis is novel and informative. It demonstrated that hemangiomas indeed express pericyte, stem cell and neural crest cell markers. This is the first study to identify factors involved in adipocyte differentiation including dlk, PPARã and KLFs. The complex adipogenesis transcription cascade complicates the ability to draw conclusion in regard to adipocyte differentiation. However, the data presented provides support for the theory that hemangiomas are pericyte-like stem cell tumors derived from the neural crest capable of adipocyte differentiation

Low temperature scattering with the R-matrix method: argon-argon scattering

Results for elastic atom-atom scattering are obtained as a first practical application of RmatReact, a new code for generating high-accuracy scattering observables from potential energy curves. RmatReact has been created in response to new experimental methods which have paved the way for the routine production of ultracold atoms and molecules, and hence the experimental study of chemical reactions involving only a small number of partial waves. Elastic scattering between argon atoms is studied here. There is an unresolved discrepancy between different argon-argon potential energy curves which give different numbers of vibrational bound states and different scattering lengths for the argon-argon dimer. Depending on the number of bound states, the scattering length is either large and positive or large and negative. Scattering observables, specifically the scattering length, effective range, and partial and total cross-sections, are computed at low collision energies and compared to previous results. In general, good agreement is obtained, although our full scattering treatment yields resonances which are slightly lower in energy and narrower than previous determinations using the same potential energy curve.Comment: 26 pages, 9 figures, 3 table

Playful activism : memetic performances of palestinian resistance in TikTok #Challenges

Palestinians have long been using social media as a tool for activism. Each platform provides unique socio-technological affordances that shape users' communicative practices as networked publics. Focusing on the video-sharing platform TikTok, which has taken a "serious turn" in recent years, this article examines how Palestinian users performed playful acts of resistance during the escalation of violence between Palestinians and Israelis in May 2021. Applying a multimodal analysis to 500 TikTok videos posted during the conflict under #gazaunderattack, we identify three memetic templates (#challenge)-(1) lip-syncing, (2) duets, and (3) point-of-view-that unfold the ways TikTok's design and its play-based affordances ignite affective streams of audiovisual content that render playful activism in times of conflict. Driven by TikTok's culture of imitation and competition, playful activism enables the participation of ordinary users in political emerging events with the help of looping meme videos composed of collaborative, dialogic, and communal socio-technical functions. Playful activism transforms users' ritualized performances into powerful political instruments on TikTok and makes democratic participation more relatable, tangible, and accessible to various audiences

The use of technology in healthcare education: a literature review

This paper presents a literature review into the use of technology in healthcare education. A search of three electronic databases resulted in 20 articles for inclusion in the review. The articles were synthesised into a narrative review. The review identified four key themes across the literature: the types of technologies used in healthcare education; the integration of technology into the healthcare curriculum; the skills and knowledge of the healthcare educators; and the benefits of using technology for the learners. The literature demonstrated that a wide range of technologies are now used within healthcare education, and this requires educators to adapt their practice and develop their technical skills to be competent users. The successful integration of technology into healthcare curriculums can be beneficial for healthcare learners by developing their clinical and professional skills, and enhancing their learning experience