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The relationship between B-field orientation and density structure in molecular clouds is often assessed using the histogram of relative orientations (HRO). We perform a plane-of-the-sky geometrical analysis of projected B-fields, by interpreting HROs in dense, spheroidal, pre-stellar, and protostellar cores. We use James Clerk Maxwell Telescope POL-2 850 |$\mu$| m polarization maps and Herschel column density maps to study dense cores in the Ophiuchus molecular cloud complex. We construct two-dimensional core models, assuming Plummer column density profiles and modelling both linear and hourglass B-fields. We find that high-aspect ratio ellipsoidal cores produce strong HRO signals, as measured using the shape parameter |$\xi$|⁠. Cores with linear fields oriented |$<\!\! 45 ^{\circ }$| from their minor axis produce constant HROs with |$-1 \lt \xi \lt 0$|⁠ , indicating that fields are preferentially parallel to column density gradients. Fields parallel to the core minor axis produce the most negative value of |$\xi$|⁠. For low-aspect ratio cores, |$\xi \approx 0$| for linear fields. Hourglass fields produce a minimum in |$\xi$| at intermediate densities in all cases, converging to the minor-axis-parallel linear field value at high and low column densities. We create HROs for six dense cores in Ophiuchus. |$\rho$| Oph A and IRAS 16293 have high aspect ratios and preferentially negative HROs, consistent with moderately strong field behaviour. |$\rho$| Oph C, L1689A, and L1689B have low aspect ratios, and |$\xi \approx 0$|⁠. |$\rho$| Oph B is too complex to be modelled using a simple spheroidal field geometry. We see no signature of hourglass fields, agreeing with previous findings that dense cores generally exhibit linear fields on these size scales. [ABSTRACT FROM AUTHOR]

Polarized dust emission is a key tracer in the study of interstellar medium and of star formation. The observed polarization, however, is a product of magnetic field structure, dust grain properties, and grain alignment efficiency, as well as their variations in the line of sight, making it difficult to interpret polarization unambiguously. The comparison of polarimetry at multiple wavelengths is a possible way of mitigating this problem. We use data from HAWC+ /SOFIA and from SCUBA-2/POL-2 (from the BISTRO survey) to analyse the NGC 2071 molecular cloud at 154, 214, and 850  |$\mu$| m. The polarization angle changes significantly with wavelength over part of NGC 2071, suggesting a change in magnetic field morphology on the line of sight as each wavelength best traces different dust populations. Other possible explanations are the existence of more than one polarization mechanism in the cloud or scattering from very large grains. The observed change of polarization fraction with wavelength, and the 214-to-154 |$\mu$| m polarization ratio in particular, are difficult to reproduce with current dust models under the assumption of uniform alignment efficiency. We also show that the standard procedure of using monochromatic intensity as a proxy for column density may produce spurious results at HAWC+wavelengths. Using both long-wavelength (POL-2, 850  |$\mu$| m) and short-wavelength (HAWC+, |$\lesssim 200\, \mu$| m) polarimetry is key in obtaining these results. This study clearly shows the importance of multi-wavelength polarimetry at submillimetre bands to understand the dust properties of molecular clouds and the relationship between magnetic field and star formation. [ABSTRACT FROM AUTHOR]

We present the SCUBA-2 850 |$\mu$| m component of JINGLE, the new JCMT large survey for dust and gas in nearby galaxies, which with 193 galaxies is the largest targeted survey of nearby galaxies at 850  |$\mu$| m. We provide details of our SCUBA-2 data reduction pipeline, optimized for slightly extended sources, and including a calibration model adjusted to match conventions used in other far-infrared (FIR) data. We measure total integrated fluxes for the entire JINGLE sample in 10 infrared/submillimetre bands, including all WISE, Herschel -PACS, Herschel -SPIRE, and SCUBA-2 850  |$\mu$| m maps, statistically accounting for the contamination by CO(J = 3–2) in the 850  |$\mu$| m band. Of our initial sample of 193 galaxies, 191 are detected at 250  |$\mu$| m with a ≥5σ significance. In the SCUBA-2 850  |$\mu$| m band we detect 126 galaxies with ≥3σ significance. The distribution of the JINGLE galaxies in FIR/sub-millimetre colour–colour plots reveals that the sample is not well fit by single modified-blackbody models that assume a single dust-emissivity index (β). Instead, our new 850  |$\mu$| m data suggest either that a large fraction of our objects require β < 1.5, or that a model allowing for an excess of sub-mm emission (e.g. a broken dust emissivity law, or a very cold dust component ≲10 K) is required. We provide relations to convert FIR colours to dust temperature and β for JINGLE-like galaxies. For JINGLE the FIR colours correlate more strongly with star-formation rate surface-density rather than the stellar surface-density, suggesting heating of dust is greater due to younger rather than older stellar-populations, consistent with the low proportion of early-type galaxies in the sample. [ABSTRACT FROM AUTHOR]

NGC 4654, an Scd galaxy in the Virgo cluster, is asymmetric in its H i distribution, with a sharp cutoff in the north-west and a long tail in the south-east, while its CO is extended to the north-west where the H i is compressed and hence its surface density is increased. This galaxy is reported to have experienced tidal interaction about 500 Myr ago, and to have been undergoing ram pressure continuously until now. To investigate the environmental effects on the interstellar medium, we make a point-to-point comparison between the H i, H2, and star formation rate surface densities. The mean H i surface density at the north-west is about 25 M⊙ pc−2, which is higher than the threshold where H i surface density begins to saturate. The ratio of molecular to atomic hydrogen (Rmol) in the north-west region is lower than that of the other regions. Star formation efficiency with respect to the molecular gas (SFEH2) at the north-west appears to be higher than the other regions with the same total gas surface density. We discuss the high SFEH2 at the north-west region and propose the possibility that the intracluster medium (ICM) pushes the low-metal gas from the outer radius into the north-west region. In a low-metallicity environment, it has been reported that high ΣH i can exist without saturation and stars can be formed from the cold atomic hydrogen phase rather than from the molecular phase. Suggestion of inflow of the outer metal-poor gas into the north-west explains well the high ΣH i and SFEH2 of the north-west region. We suggest another possibility, of H i conversion into H2 due to the increase of gas surface density and midplane pressure due to the ICM pressure at the north-west. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of trunk stability training based on visual feedback on trunk stability, balance, and upper limb function in patients with stroke. Twenty-eight patients with chronic stroke were randomly assigned to either a trunk support group (n = 14) or a trunk restraint group (n = 14) that practiced upper limb training with trunk support and trunk restraint, respectively, based on visual feedback for 30 min per day, three times per week, for 4 weeks. The postural assessment scale for stroke (PASS) was used to assess the stability of patients, and the functional reaching test (FRT) was performed to assess balance. To assess upper extremity function, a range of motion (ROM) test, manual muscle testing (MMT), and Fugl–Meyer assessment-upper limb (FMA-upper limb) were performed. Consequently, both groups showed significant differences before and after training in the PASS, FRT, shoulder flexion ROM, triceps brachii MMT, and FMA-upper limb (p < 0.05), while the trunk support group showed more significant improvements than the trunk restraint group in the PASS, FRT, and FMA-upper limb (p < 0.05). Trunk support-based upper limb training effectively improved trunk stability, balance, and upper limb function and is beneficial as an upper limb training method. Providing trunk support is more effective than restricting the trunk; trunk support-based upper limb training is expected to promote voluntary participation when combined with visual feedback. [ABSTRACT FROM AUTHOR]