Thermal and Non-thermal X-Rays from the LMC Super Bubble 30 Dor C

We report on the discovery of thermal and non-thermal X-rays from the shells of the super bubble (SB) 30 Dor C in the Large Magellanic Cloud (LMC). The X-ray morphology is a nearly circular shell with a radius of about 40 pc, which is bright on the northern and western sides. The spectra of the shells are different from region to region. The southern shell shows clear emission lines, and is well fitted with a model of a thin-thermal plasma (kT = 0.21keV) in non-equilibrium ionization (NEI) plus a power-law component. This thermal plasma is located inside of the H alpha emission, which is the outer edge of the shell of the SB. The northern and western sides of the SB are dim in H alpha emission, but are bright in non-thermal (power-law) X-rays with a photon index of 2.1-2.9. The non-thermal X-ray shell traces the outer boundary of the radio shell. These features of thin-thermal and non-thermal X-rays are similar to those of SN 1006, a prototype of synchrotron X-ray shell, but the non-thermal component of 30 Dor C is about ten-times brighter than that of SN 1006. 30 Dor C is the first candidate of an extragalactic SB, in which energetic electrons are accelerating in the shell. The age is much older than that of SN 1006, and hence the particle acceleration time in this SB may be longer than those in normal shell-like SNRs. We found point-like sources associated with some of tight star clusters. The X-ray luminosity and spectrum are consistent with those of young clusters of massive stars. Point-like sources with non-thermal spectra are also found in the SB. These may be background objects (AGNs) or stellar remnants (neutron stars or black holes).Comment: 11 pages, 6 figures, Accepted for publication in ApJ, the paper with full resolution images in http://www-cr.scphys.kyoto-u.ac.jp/member/bamba/Paper/30DorC.pd

Spitzer observations of the N157B supernova remnant and its surroundings

(Aims): We study the LMC interstellar medium in the field of the nebula N157B, which contains a supernova remnant, an OB association, ionized gas, and high-density dusty filaments in close proximity. We investigate the relative importance of shock excitation by the SNR and photo-ionization by the OB stars, as well as possible interactions between the supernova remnant and its environment. (Methods): We apply multiwavelength mapping and photometry, along with spatially resolved infrared spectroscopy, to identifying the nature of the ISM using new infrared data from the Spitzer space observatory and X-ray, optical, and radio data from the literature. (Results): The N157B SNR has no infrared counterpart. Infrared emission from the region is dominated by the compact blister-type HII region associated with 2MASS J05375027-6911071 and excited by an O8-O9 star. This object is part of an extended infrared emission region that is associated with a molecular cloud. We find only weak emission from the shock-indicator [FeII], and both the excitation and the heating of the extended cloud are dominated by photo-ionization by the early O stars of LH99. (Conclusions): Any possible impact by the expanding SNR does not now affect the extended cloud of molecules and dust, despite the apparent overlap of SNR X-ray emission with infrared and Ha emission from the cloud. This implies that the supernova progenitor cannot have been more massive than about 25 solar masses.Comment: 10 pages, 8 figures, published in A&

Multi-scenario modelling of learning

International audienceDesigning an educational scenario is a sensitive and challenging activity because it is the vector of learning. However, the designed scenario may not correspond to some learners’ characteristics (pace of work, cognitive styles, emotional factors, prerequisite knowledge, …). To personalize the learning task and adapt it gradually to each learner, several scenarios are needed. Adaptation and personalization are difficult because it is necessary on the one hand to know in advance the profiles and on the other hand to produce the multiple scenarios corresponding to these profiles. Our model allows to design many scenarios without knowing the learner profiles beforehand. Furthermore, it offers each learner opportunities to choose a scenario and to change it during their learning process. The model ensures that all announced objectives have enough resources for acquiring knowledge and activities for evaluation

Covalent enzyme coupling on cellulose acetate membranes for glucose sensor development

International audienceMethods for immobilizing glucose oxidase (GOx) on cellulose acetate (CA) membranes are compared. The optimal method involves covalent coupling of bovine serum albumin (BSA) to CA membrane and a subsequent reaction of the membrane with GOx, which has previously been activated with an excess of p-benzoquinone. This coupling procedure is fairly reproducible and allows the preparation of thin membranes (5-20 µm) showing high surface activities (1-3 U/cm2) which are stable over a period of 1-3 months. Electrochemical and radiolabeling experiments show that enzyme inactivation as a result of immobilization is negligible. A good correlation between surface activity of membranes and their GOx load is observed

Scale up mHealth HIV interventions: site and public health perspectives and lessons learned from P3

A number of mobile health (mHealth) interventions have been shown to be effective and highly acceptable tools for improving human immunodeficiency virus (HIV) prevention and care for youth. Scale-up of efficacious technology-based interventions is challenging and best practices for scale-up have not been clearly established. Developers of mHealth interventions should have plans in mind for wide scale implementation throughout all stages of development including planning, during trials and during analysis and dissemination. We discuss an approach of focus on researchers, funders and potential implementers including members of the community, public health practitioners and policymakers during initial planning, trials, analysis and dissemination, and planning for scale-up. Development of the P3 (Prepared, Protected, emPowered) mobile application (app), an intervention built to encourage and increase pre-exposure prophylaxis (PrEP) adherence among young men who have sex with men (YMSM) and young transgender women who have sex with men (YTWSM), is discussed in terms of designing for scale-up and lessons learned

Cost of peer mystery shopping to increase cultural competency in community clinics offering HIV/STI testing to young men who have sex with men: results from the get connected trial

IntroductionCultural competency has been identified as a barrier to lesbian, gay, bisexual and transgender (LGBT) populations seeking care. Mystery shopping has been widely employed in the formal health care sector as a quality improvement (QI) tool to address specific client needs. The approach has had limited use in community-based organizations due in part to lack of knowledge and resource requirement concerns. Several mystery shopping initiatives are now being implemented which focus on the LGBT population with the goal of reducing barriers to accessing care. One subset targets men who have sex with men (MSM) to increase uptake of human immunodeficiency virus (HIV) testing. No study investigates the costs of these initiatives. Get Connected was a randomized control trial with the objective of increasing uptake of HIV-prevention services among young men who have sex with men (YMSM) through use of a resource-locator application (App). The initial phase of the trial employed peer-led mystery shopping to identify culturally competent HIV testing sites for inclusion in the App. The second phase of the trial randomized YMSM to test the efficacy of the App. Our objective was to determine the resource inputs and costs of peer-led mystery shopping to identify clinics for inclusion in the App as costs would be critical in informing possible adoption by organizations and sustainability of this model.MethodsThrough consultation with study staff, we created a resource inventory for undertaking the community-based, peer-led mystery shopping program. We used activity-based costing to price each of the inputs. We classified inputs as start-up and those for on-going implementation. We calculated costs for each category, total costs and cost per mystery shopper visit for the four-month trial and annually to reflect standard budgeting periods for data collected from September of 2019 through September of 2020.ResultsRecruitment and training of peer mystery shoppers were the most expensive tasks. Average start-up costs were $10,001 (SD$39.8). Four-month average implementation costs per visit were $228 (SD$1.97). Average annual implementation costs per visit were 33% lower at $151 (SD$5.60).ConclusionsPeer-led, mystery shopping of HIV-testing sites is feasible, and is likely affordable for medium to large public health departments