VLA observations of water masers towards 6.7 GHz methanol maser sources

22 GHz water and 6.7 GHz methanol masers are usually thought as signposts of early stages of high-mass star formation but little is known about their associations and the physical environments they occur in. The aim was to obtain accurate positions and morphologies of the water maser emission and relate them to the methanol maser emission recently mapped with Very Long Baseline Interferometry. A sample of 31 methanol maser sources was searched for 22 GHz water masers using the VLA and observed in the 6.7 GHz methanol maser line with the 32 m Torun dish simultaneously. Water maser clusters were detected towards 27 sites finding 15 new sources. The detection rate of water maser emission associated with methanol sources was as high as 71%. In a large number of objects (18/21) the structure of water maser is well aligned with that of the extended emission at 4.5 $\mu$m confirming the origin of water emission from outflows. The sources with methanol emission with ring-like morphologies, which likely trace a circumstellar disk/torus, either do not show associated water masers or the distribution of water maser spots is orthogonal to the major axis of the ring. The two maser species are generally powered by the same high-mass young stellar object but probe different parts of its environment. The morphology of water and methanol maser emission in a minority of sources is consistent with a scenario that 6.7 GHz methanol masers trace a disc/torus around a protostar while the associated 22 GHz water masers arise in outflows. The majority of sources in which methanol maser emission is associated with the water maser appears to trace outflows. The two types of associations might be related to different evolutionary phases.Comment: accepted by Astronomy & Astrophysic

The power of the Ingroup for promoting collective action: How distinctive treatment from fellow minority members motivates collective action

This is the final version. Available on open access from Elsevier via the DOI in this recordAround the world, protests tied to the Black Lives Matter movement are highlighting myriad forms of unjust treatment that racial and ethnic minorities face, and prompting countries to reckon with these injustices. When considering racial/ethnic minorities’ motivation to engage in these collective actions (alongside allies), it is certainly spurred in part by witnessing and experiencing such unjust treatment. Yet because this intergroup mistreatment commands strong attention (rightly so), less attention has been given to another potential force behind minorities’ collective action motivations – the (positive) treatment coming from members of their own racial/ethnic group. Bridging theory on intragroup relations and collective action, in four studies we demonstrate that when racial/ethnic minorities are shown appreciation for the ideas and insights they bring to their group – for instance, when fellow members seek them out for their ideas during conversation; expressions of distinctive treatment – it positively affects their sense of value to the group as a whole, and, in turn, their willingness to engage in collective action. Moreover, we demonstrate how these processes feed into other established explanations for collective action, outlined in the social identity model of collective action (SIMCA; e.g., perceived injustice). We also show that even a single expression of distinctive treatment from a few unknown ingroup members can have positive effects, especially when those members have high standing within the group. Overall, this illustrates the power of the ingroup – how taking opportunities to seek out a fellow member’s ideas and perspectives can be a potent force for promoting collective action.European Association of Social PsychologySociety for Personality and Social Psycholog

Excited-state hydroxyl maser catalogue from the methanol multibeam survey -- I. Positions and Variability

We present the results of the first complete unbaised survey of the Galactic Plane for 6035-MHz excited-state hydroxyl masers undertaken as part of the Methanol Multibeam Survey. These observations cover the Galactic longitude ranges $186^{\circ}Peer reviewedFinal Published versio

Intra-subject repeatability of in vivo intervertebral motion parameters using quantitative fluoroscopy.

Purpose: In vivo quantification of intervertebral motion through imaging has progressed to a point where biomarkers for low back pain are emerging. This makes possible deeper study of the condition’s biometrics. However, the measurement of change over time involves error. The purpose of this prospective investigation is to determine the intra-subject repeatability of six in vivo intervertebral motion parameters using quantitative fluoroscopy. Methods: Intra-subject reliability (ICC) and minimal detectable change (MDC) of baseline to 6-week follow-up measurements were calculated for 6 lumbar spine intervertebral motion parameters in 109 healthy volunteers. A standardised quantitative fluoroscopy (QF) protocol was used to provide measurements in the coronal and sagittal planes using both passive recumbent and active weight bearing motion. Parameters were: intervertebral range of motion (IV-RoM), laxity, motion sharing inequality (MSI), motion sharing variability (MSV), flexion translation, and anterior disc height change during flexion. Results: The best overall intra subject reliability (ICC) and agreement (MDT) were for disc height (ICC 0.89, MDC 43%) and IV-RoM (ICC 0.96, MDC 60%) and the worst for MSV (ICC 0.04, MCD 408%). Laxity, MSI and translation had acceptable reliability (most ICCs >0.60), but not agreement (MDC >85%). Conclusion: Disc height and IV-RoM measurement using QF could be considered for randomised trials while laxity, MSI and translation could be considered for moderators, correlates or mediators of patient reported outcomes. MSV had both poor reliability and agreement over 6 weeks

Exploring the nature and variation of the stigma associated with loneliness

This is the final version. Available on open access from SAGE Publications via the DOI in this recordThe current study uses data from The British Broadcasting Corporation Loneliness Experiment to explore the social stigma of loneliness and how it varies by gender, age and cultural individualism. We examined stigmatizing judgements of people who are lonely (impressions of those who feel lonely and attributions for loneliness), perceived stigma in the community and self-stigma (shame for being lonely and inclination to conceal loneliness), while controlling for participants’ own feelings of loneliness. The scores on most measures fell near the mid-point of the scales, but stigmatizing perceptions depended on the measure of stigmatization that was used and on age, gender and country-level individualism. Multilevel analyses revealed that men had more stigmatizing perceptions, more perceived community stigma, but less self-stigma than women; young people had higher scores than older people on all indicators except for internal versus external attributions and people living in collectivist countries perceived loneliness as more controllable and perceived more stigma in the community than people living in individualistic countries. Finally, young men living in individualistic countries made the most internal (vs. external) attributions for loneliness. We discuss the implications of these findings for understandings of loneliness stigma and interventions to address loneliness.Wellcome TrustAuthor accepted manuscript replaced with published version by Caroline Huxtable on 2022-05-0

European VLBI Network imaging of 6.7 GHz methanol masers

Context. Methanol masers at 6.7 GHz are well known tracers of high-mass star-forming regions. However, their origin is still not clearly understood. Aims. We aimed to determine the morphology and velocity structure for a large sample of the maser emission with generally lower peak flux densities than those in previous surveys. Methods. Using the European VLBI Network (EVN) we imaged the remaining sources from a sample of sources that were selected from the unbiased survey using the Torun 32 m dish. In this paper we report the results for 17 targets. Together they form a database of a total of 63 source images with high sensitivity (3σ rms = 15−30 mJy/beam ), milliarcsecond angular resolution (6−10 mas) and very good spectral resolution (0.09 km/s or 0.18 km/s ) for detailed studies. Results. We studied in detail the properties of the maser clouds and calculated the mean and median values of the projected size (17.4 ± 1.2 au and 5.5 au, respectively) as well as the FWHM of the line (0.373 ± 0.011 km/s and 0.315 km/s for the mean and median values, respectively), testing whether it was consistent with Gaussian profile. We also found maser clouds with velocity gradients (71%) that ranged from 0.005 km/s/au to 0.210 km/s/au. We tested the kinematic models to explain the observed structures of the 6.7 GHz emission. There were targets where the morphology supported the scenario of a rotating and expanding disk or a bipolar outflow. Comparing the interferometric and single-dish spectra we found that, typically, 50–70% of the flux was missing. This phenomena is not strongly related to the distance of the source. Conclusions. The EVN imaging reveals that in the complete sample of 63 sources the ring-like morphology appeared in 17% of sources, arcs were seen in a further 8%, and the structures were complex in 46% cases. The ultra-compact (UC) H II regions coincide in position in the sky for 13% of the sources. They are related both to extremely high and low luminosity masers from the sample

1,6-Cyclophellitol Cyclosulfates : A New Class of Irreversible Glycosidase Inhibitor

The essential biological roles played by glycosidases, coupled to the diverse therapeutic benefits of pharmacologically targeting these enzymes, provide considerable motivation for the development of new inhibitor classes. Cyclophellitol epoxides and aziridines are recently established covalent glycosidase inactivators. Inspired by the application of cyclic sulfates as electrophilic equivalents of epoxides in organic synthesis, we sought to test whether cyclophellitol cyclosulfates would similarly act as irreversible glycosidase inhibitors. Here we present the synthesis, conformational analysis, and application of novel 1,6-cyclophellitol cyclosulfates. We show that 1,6-epi-cyclophellitol cyclosulfate (α-cyclosulfate) is a rapidly reacting α-glucosidase inhibitor whose 4C1 chair conformation matches that adopted by α-glucosidase Michaelis complexes. The 1,6-cyclophellitol cyclosulfate (β-cyclosulfate) reacts more slowly, likely reflecting its conformational restrictions. Selective glycosidase inhibitors are invaluable as mechanistic probes and therapeutic agents, and we propose cyclophellitol cyclosulfates as a valuable new class of carbohydrate mimetics for application in these directions

1,6-Cyclophellitol Cyclosulfates : A New Class of Irreversible Glycosidase Inhibitor

The essential biological roles played by glycosidases, coupled to the diverse therapeutic benefits of pharmacologically targeting these enzymes, provide considerable motivation for the development of new inhibitor classes. Cyclophellitol epoxides and aziridines are recently established covalent glycosidase inactivators. Inspired by the application of cyclic sulfates as electrophilic equivalents of epoxides in organic synthesis, we sought to test whether cyclophellitol cyclosulfates would similarly act as irreversible glycosidase inhibitors. Here we present the synthesis, conformational analysis, and application of novel 1,6-cyclophellitol cyclosulfates. We show that 1,6-epi-cyclophellitol cyclosulfate (α-cyclosulfate) is a rapidly reacting α-glucosidase inhibitor whose 4C1 chair conformation matches that adopted by α-glucosidase Michaelis complexes. The 1,6-cyclophellitol cyclosulfate (β-cyclosulfate) reacts more slowly, likely reflecting its conformational restrictions. Selective glycosidase inhibitors are invaluable as mechanistic probes and therapeutic agents, and we propose cyclophellitol cyclosulfates as a valuable new class of carbohydrate mimetics for application in these directions

Ammonia masers toward G358.931-0.030

We report the detection of ammonia masers in the non-metastable (6, 3), (7, 5) and (6, 5) transitions, the latter is the first unambiguous maser detection of that transition ever made. Our observations include the first VLBI detection of ammonia maser emission, which allowed effective constrain of the (6, 5) maser brightness temperature. The masers were detected towards G358.931-0.030, a site of 6.7-GHz class~II methanol maser emission that was recently reported to be undergoing a period of flaring activity. These ammonia masers appear to be flaring contemporaneously with the class~II methanol masers during the accretion burst event of G358.931-0.030. This newly detected site of ammonia maser emission is only the twelfth such site discovered in the Milky Way. We also report the results of an investigation into the maser pumping conditions, for all three detected masing transitions, through radiative transfer calculations constrained by our observational data. These calculations support the hypothesis that the ammonia (6, 5) maser transition is excited through high colour temperature infrared emission, with the (6, 5) and (7, 5) transition line-ratio implying dust temperatures >400K. Additionally, we detect significant linearly polarised emission from the ammonia (6, 3) maser line. Alongside our observational and radiative transfer calculation results, we also report newly derived rest frequencies for the ammonia (6, 3) and (6, 5) transitions.Comment: Accepted into MNRAS 2023 April 24. 13 pages, 5 figures, 3 table

GASKAP -- The Galactic ASKAP Survey

A survey of the Milky Way disk and the Magellanic System at the wavelengths of the 21-cm atomic hydrogen (HI) line and three 18-cm lines of the OH molecule will be carried out with the Australian Square Kilometre Array Pathfinder telescope. The survey will study the distribution of HI emission and absorption with unprecedented angular and velocity resolution, as well as molecular line thermal emission, absorption, and maser lines. The area to be covered includes the Galactic plane (|b|< 10deg) at all declinations south of delta = +40deg, spanning longitudes 167deg through 360deg to 79deg at b=0deg, plus the entire area of the Magellanic Stream and Clouds, a total of 13,020 square degrees. The brightness temperature sensitivity will be very good, typically sigma_T ~ 1 K at resolution 30arcsec and 1 km/s. The survey has a wide spectrum of scientific goals, from studies of galaxy evolution to star formation, with particular contributions to understanding stellar wind kinematics, the thermal phases of the interstellar medium, the interaction between gas in the disk and halo, and the dynamical and thermal states of gas at various positions along the Magellanic Stream.Comment: 45 pages, 8 figures, Pub. Astron. Soc. Australia (in press