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We have investigated the physical properties of Planck Galactic Cold Clumps (PGCCs) located in the Galactic Plane, using the JCMT Plane Survey (JPS) and the SCUBA-2 Continuum Observations of Pre-protostellar Evolution (SCOPE) survey. By utilizing a suite of molecular-line surveys, velocities, and distances were assigned to the compact sources within the PGCCs, placing them in a Galactic context. The properties of these compact sources show no large-scale variations with Galactic environment. Investigating the star-forming content of the sample, we find that the luminosity-to-mass ratio (L / M) is an order of magnitude lower than in other Galactic studies, indicating that these objects are hosting lower levels of star formation. Finally, by comparing ATLASGAL sources that are associated or are not associated with PGCCs, we find that those associated with PGCCs are typically colder, denser, and have a lower L / M ratio, hinting that PGCCs are a distinct population of Galactic Plane sources. [ABSTRACT FROM AUTHOR]

Context: Theoretical scenarios describe the phenomenon of mass accumulation by high-mass young stellar objects (HMYSOs) through disk accretion. Aims: To find out whether the rotation of the core around hyper-compact (HC) HII regions is common Methods: The molecular core G301.1364-00.2249A was selected as the subject of investigation. Observations were carried out on CH3CN, SO2, H29α radio recombination line and continuum emission. Analysis involved the "Moment 0, 1, 2" and "Population-diagram" methods. Result: The structures of G301.1364-00.2249A exhibited clear definition. CH3CN moment 0 images revealed multiple enhanced emission regions and an absorption area. The moment 1 image depicted a velocity gradient from southeast to northwest. Conclusion: The molecular gas has a rotational motion in the direction from the southeast to northwest. The rotational temperature was measured at 293 K. [ABSTRACT FROM AUTHOR]

Patients with resistant or recurrent acute lymphoblastic leukemia were treated with vindesine 3 mg/m2/IV weekly X 4, daunomycin 25 mg/m2/IV weekly X 4, and prednisone 40 mg/m2/PO daily X 28. Seventeen (44%) of 38 evaluable patients achieved complete remission. Fifty-one percent of 31 patients in first relapse achieved complete remission, while only one of five in second or third relapse and neither of two resistant to first induction achieved complete remission. The major toxicity was hematologic. The median duration of complete remission was only 6 weeks and median survival from start of the study, 3 months, with 22% patients remaining alive at 10 months. We conclude that the vindesine, prednisone, and daunomycin combination is no more effective than vincristine, prednisone, and daunomycin in achieving remission of relapsed acute lymphoblastic leukemia patients, and is more toxic than the latter regimen. [ABSTRACT FROM AUTHOR]

Context. The formation of high-mass stars remains unknown in many aspects. There are two competing families of models to explain the formation of high-mass stars. On the one hand, quasi-static models predict the existence of high-mass pre-stellar cores sustained by a high degree of turbulence. On the other hand, competitive accretion models predict that high-mass proto-stellar cores evolve from low or intermediate mass proto-stellar cores in dynamic environments. Aims. The aim of the present work is to bring observational constraints at the scale of high-mass cores (~0.03 pc). Methods. We targeted with ALMA and MOPRA a sample of nine starless massive dense cores (MDCs) discovered in a recent Herschel/HOBYS study. Their mass and size (~110 M⊙ and r = 0.1 pc, respectively) are similar to the initial conditions used in the quasi-static family of models explaining for the formation of high-mass stars. We present ALMA 1.4 mm continuum observations that resolve the Jeans length (λJeans ~ 0.03 pc) and that are sensitive to the Jeans mass (MJeans ~ 0.65 M⊙) in the nine starless MDCs, together with ALMA-12CO(2–1) emission line observations. We also present HCO+(1–0), H13CO+(1–0) and N2H+(1–0) molecular lines from the MOPRA telescope for eight of the nine MDCs. Results. The nine starless MDCs have the mass reservoir to form high-mass stars according to the criteria by Baldeschi et al. (2017). Three of the starless MDCs are subvirialized with αvir ~ 0.35, and four MDCs show sign of collapse from their molecular emission lines. ALMA observations show very little fragmentation within the MDCs. Only two of the starless MDCs host compact continuum sources, whose fluxes correspond to <3 M⊙ fragments. Therefore, the mass reservoir of the MDCs has not yet been accreted onto compact objects, and most of the emission is filtered out by the interferometer. Conclusions. These observations do not support the quasi-static models for high-mass star formation since no high-mass pre-stellar core is found in NGC 6334. The competitive accretion models, on the other hand, predict a level of fragmentation much higher than what we observe. [ABSTRACT FROM AUTHOR]

Reports on key developments relevant to archaeology and social anthropology worldwide as of March 2003. Research on Maasai settlements in southern Kenya; Behind-the-scenes information on a museum display on Etruscans, Greeks and Romans; Staging of the 3rd annual Robert Burns lunch.

Objectives: To evaluate the effectiveness of an innovative supervised exercise programme to mitigate the loss of lean body mass, functional capacity and quality of life in people with head and neck cancer, as well as to identify the optimal moment to apply it, before or after radiotherapy treatment, compared with the prescription of a physical activity plan carried out autonomously. Methods: Patients with squamous cell carcinoma of the head and neck (n = 144), treated with radiotherapy, will be randomly assigned to one of 3 comparison groups: pre-radiotherapy supervised exercise, post-radiotherapy supervised exercise and autonomous exercise, stratifying by human papillomavirus infection and previous surgery. The exercise programme will be carried out in 36 sessions over 12 weeks, combining moderate and high intensity strength and aerobic exercises. The main outcome variable is the change in lean body mass at 6 months measured by bioimpedance, while secondary variables are functional capacity, symptoms, quality of life and adverse effects. Longitudinal generalised mixed models will be used for the analyses of the repeated measurements at 3, 6, and 12 months after baseline. Conclusions: The pilot study supports the feasibility and safety of the project. However, as the programme progressed, attendance at the sessions decreased. Strategies will be necessary for increasing attendance, as well as involving the patient in their recovery and other incentives. Follow-up after treatment to assess acute/late toxicity will enable us to know the response to both the exercise programme and its adherence. Trial registration: NCT04658706 Date and version identifier: March 1, 2023. Version 1.1 [ABSTRACT FROM AUTHOR]

Young massive clusters (YMCs) are the most compact, high-mass stellar systems still forming at the present day. The precursor clouds to such systems are, however, rare due to their large initial gas mass reservoirs and rapid dispersal time-scales due to stellar feedback. None the less, unlike their high- z counterparts, these precursors are resolvable down to the sites of individually forming stars, and hence represent the ideal environments in which to test the current theories of star and cluster formation. Using high angular resolution (1 arcsec / 0.05 pc) and sensitivity ALMA observations of two YMC progenitor clouds in the Galactic Centre, we have identified a suite of molecular line transitions – e.g. c-C3H2 (7 − 6) – that are believed to be optically thin, and reliably trace the gas structure in the highest density gas on star-forming core scales. We conduct a virial analysis of the identified core and proto-cluster regions, and show that half of the cores (5/10) and both proto-clusters are unstable to gravitational collapse. This is the first kinematic evidence of global gravitational collapse in YMC precursor clouds at such an early evolutionary stage. The implications are that if these clouds are to form YMCs, then they likely do so via the 'conveyor-belt' mode, whereby stars continually form within dispersed dense gas cores as the cloud undergoes global gravitational collapse. The concurrent contraction of both the cluster-scale gas and embedded (proto-)stars ultimately leads to the high (proto-)stellar density in YMCs. [ABSTRACT FROM AUTHOR]

Radio continuum observations using the Australia telescope compact array at 5.5, 9.0, 17.0 and 22.8 GHz have detected free-free emission associated with 45 of 49 massive young stellar objects and HII regions. Of these, 26 sources are classified as ionized jets (12 of which are candidates), 2 as ambiguous jets or disc winds, 1 as a disc-wind, 14 as HII regions and 2 were unable to be categorized. Classification as ionized jets is based upon morphology, radio flux and spectral index, in conjunction with previous observational results at other wavelengths. Radio luminosity and momentum are found to scale with bolometric luminosity in the same way as low-mass jets, indicating a common mechanism for jet production across all masses. In 13 of the jets, we see associated non-thermal/optically thin lobes resulting from shocks either internal to the jet and/or at working surfaces. 10 jets display non-thermal (synchrotron emission) spectra in their lobes, with an average spectral index of α =-0.55 consistent with Fermi acceleration in shocks. This shows that magnetic fields are present, in agreement with models of jet formation incorporating magnetic fields. Since the production of collimated radio jets is associated with accretion processes, the results presented in this paper support the picture of disc-mediated accretion for the formation of massive stars with an upper limit on the jet phase lasting approximately 6.5×104 yr. Typical mass-loss rates in the jet are found to be 1.4× 10-5M⊙ yr-1 with associated momentum rates of the order of (1-2) × 10-2 M⊙ km s-1 yr-1. [ABSTRACT FROM AUTHOR]