ObjectiveExamine the effectiveness of specific modes of exercise training in non-specific chronic low back pain (NSCLBP).DesignNetwork meta-analysis (NMA).Data sourcesMEDLINE, CINAHL, SPORTDiscus, EMBASE, CENTRAL.Eligibility criteriaExercise training randomised controlled/clinical trials in adults with NSCLBP.ResultsAmong 9543 records, 89 studies (patients=5578) were eligible for qualitative synthesis and 70 (pain), 63 (physical function), 16 (mental health) and 4 (trunk muscle strength) for NMA. The NMA consistency model revealed that the following exercise training modalities had the highest probability (surface under the cumulative ranking (SUCRA)) of being best when compared with true control: Pilates for pain (SUCRA=100%; pooled standardised mean difference (95% CI): −1.86 (–2.54 to –1.19)), resistance (SUCRA=80%; −1.14 (–1.71 to –0.56)) and stabilisation/motor control (SUCRA=80%; −1.13 (–1.53 to –0.74)) for physical function and resistance (SUCRA=80%; −1.26 (–2.10 to –0.41)) and aerobic (SUCRA=80%; −1.18 (–2.20 to –0.15)) for mental health. True control was most likely (SUCRA≤10%) to be the worst treatment for all outcomes, followed by therapist hands-off control for pain (SUCRA=10%; 0.09 (–0.71 to 0.89)) and physical function (SUCRA=20%; −0.31 (–0.94 to 0.32)) and therapist hands-on control for mental health (SUCRA=20%; −0.31 (–1.31 to 0.70)). Stretching and McKenzie exercise effect sizes did not differ to true control for pain or function (p>0.095; SUCRA<40%). NMA was not possible for trunk muscle endurance or analgesic medication. The quality of the synthesised evidence was low according to Grading of Recommendations Assessment, Development and Evaluation criteria.Summary/conclusionThere is low quality evidence that Pilates, stabilisation/motor control, resistance training and aerobic exercise training are the most effective treatments, pending outcome of interest, for adults with NSCLBP. Exercise training may also be more effective than therapist hands-on treatment. Heterogeneity among studies and the fact that there are few studies with low risk of bias are both limitations.

Whether supernovae are major sources of dust in galaxies is a long-standing debate. We present infrared and submillimeter photometry and spectroscopy from the Herschel Space Observatory of the Crab Nebula between 51 and 670 µm as part of the Mass Loss from Evolved StarS program. We compare the emission detected with Herschel with multiwavelength data including millimeter, radio, mid-infrared and archive optical images. We carefully remove the synchrotron component using the Herschel and Planck fluxes measured in the same epoch. The contribution from line emission is removed using Herschel spectroscopy combined with Infrared Space Observatory archive data. Several forbidden lines of carbon, oxygen and nitrogen are detected where multiple velocity components are resolved, deduced to be from the nitrogen-depleted, carbon-rich ejecta. No spectral lines are detected in the SPIRE wavebands; in the PACS bands, the line contribution is 5% and 10% at 70 and 100 µm and negligible at 160 µm. After subtracting the synchrotron and line emission, the remaining farinfrared continuum can be fit with two dust components. Assuming standard interstellar silicates, the mass of the cooler component is 0.24 +0.32 −0.08 M ⊙ for T = 28.1 +5.5 −3.2 K. Amorphous carbon grains require 0.11 ± 0.01 M ⊙ of dust with T = 33.8 +2.3 −1.8 K. A single temperature modified blackbody with 0.14 M ⊙ and 0.08 M ⊙ for silicate and carbon dust respectively, provides an adequate fit to the farinfrared region of the spectral energy distribution but is a poor fit at 24-500 µm. The Crab Nebula has condensed most of the relevant refractory elements into dust, suggesting the formation of dust in core-collapse supernova ejecta is efficient.

Noble gas molecules have not hitherto been detected in space. From spectra obtained with the Herschel Space Observatory, we report the detection of emission in the 617.5- and 1234.6-gigahertz J = 1-0 and 2-1 rotational lines of (36)ArH(+) at several positions in the Crab Nebula, a supernova remnant known to contain both molecular hydrogen and regions of enhanced ionized argon emission. Argon-36 is believed to have originated from explosive nucleosynthesis in massive stars during core-collapse supernova events. Its detection in the Crab Nebula, the product of such a supernova event, confirms this expectation. The likely excitation mechanism for the observed (36)ArH(+) emission lines is electron collisions in partially ionized regions with electron densities of a few hundred per centimeter cubed.

We have constructed MOCASSIN photoionization plus dust radiative transfer models for the Crab Nebula corecollapse supernova (CCSN) remnant, using either smooth or clumped mass distributions, in order to determine the chemical composition and masses of the nebular gas and dust. We computed models for several different geometries suggested for the nebular matter distribution but found that the observed gas and dust spectra are relatively insensitive to these geometries, being determined mainly by the spectrum of the pulsar wind nebula which ionizes and heats the nebula. Smooth distribution models are ruled out since they require 16-49 M of gas to fit the integrated optical nebular line fluxes, whereas our clumped models require 7.0 M of gas. A global gas-phase C/O ratio of 1.65 by number is derived, along with a He/H number ratio of 1.85, neither of which can be matched by current CCSN yield predictions. A carbonaceous dust composition is favoured by the observed gas-phase C/O ratio: amorphous carbon clumped model fits to the Crab's Herschel and Spitzer infrared spectral energy distribution imply the presence of 0.18-0.27 M of dust, corresponding to a gas to dust mass ratio of 26-39. Mixed dust chemistry models can also be accommodated, comprising 0.11-0.13 M of amorphous carbon and 0.39-0.47 M of silicates. Power-law grain size distributions with mass distributions that are weighted towards the largest grain radii are derived, favouring their longer-term survival when they eventually interact with the interstellar medium. The total mass of gas plus dust in the Crab Nebula is 7.2±0.5 M , consistent with a progenitor star mass of ∼ 9 M .

Nonspecific chronic low back pain (CLBP) is a common clinical condition that has impacts at both the individual and societal level. Pain intensity is a primary outcome used in clinical practice to quantify the severity of CLBP and the efficacy of its treatment; however, pain is a subjective experience that is impacted by a multitude of factors. Moreover, differences in effect sizes for pain intensity are not observed between common conservative treatments, such as spinal manipulative therapy, cognitive behavioral therapy, acupuncture, and exercise training. As pain science evolves, the biopsychosocial model is gaining interest in its application for CLBP management. The aim of this article is to discuss our current scientific understanding of pain and present why additional factors should be considered in conservative CLBP management. In addition to pain intensity, we recommend that clinicians should consider assessing the multidimensional nature of CLBP by including physical (disability, muscular strength and endurance, performance in activities of daily living, and body composition), psychological (kinesiophobia, fear‐avoidance, pain catastrophizing, pain self‐efficacy, depression, anxiety, and sleep quality), social (social functioning and work absenteeism), and health‐related quality‐of‐life measures, depending on what is deemed relevant for each individual. This review also provides practical recommendations to clinicians for the assessment of outcomes beyond pain intensity, including information on how large a change must be for it to be considered “real” in an individual patient. This information can guide treatment selection when working with an individual with CLBP.