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Many dwarf galaxies have disproportionately rich globular cluster (GC) systems for their luminosities. Moreover, the GCs tend to be preferentially associated with the most metal-poor stellar populations in their parent galaxies, making them attractive tracers of the halos of dwarf (and larger) galaxies. In this contribution, I briefly discuss some constraints on cluster disruption obtained from studies of metal-poor GCs in dwarf galaxies. I then discuss our recent work on detailed abundance analysis from integrated-light spectroscopy of GCs in Local Group dwarf galaxies.

An overview of our current understanding of the formation and evolution of star clusters is given, with the main emphasis on high-mass clusters. Clusters form deeply embedded within dense clouds of molecular gas. Left-over gas is cleared within a few million years and, depending on the efficiency of star formation, the clusters may disperse almost immediately or remain gravitationally bound. Current evidence suggests that a small percentage of star formation occurs in clusters that remain bound, although it is not yet clear whether this fraction is truly universal. Internal two-body relaxation and external shocks will lead to further, gradual dissolution on time scales of up to a few hundred million years for low-mass open clusters in the Milky Way, while the most massive clusters (>105M) have lifetimes comparable to or exceeding the age of the Universe. The low-mass end of the initial cluster mass function is well approximated by a power-law distribution, Formula , but there is mounting evidence that quiescent spiral discs form relatively few clusters with masses M>2x105M. In starburst galaxies and old globular cluster systems, this limit appears to be higher, at least several x106M. The difference is likely related to the higher gas densities and pressures in starburst galaxies, which allow denser, more massive giant molecular clouds to form. Low-mass clusters may thus trace star formation quite universally, while the more long-lived, massive clusters appear to form preferentially in the context of violent star formation. [ABSTRACT FROM AUTHOR]

We use the Panchromatic Hubble Andromeda Treasury survey data set to perform spatially resolved measurements of star cluster formation efficiency (Γ), the fraction of stellar mass formed in long-lived star clusters. We use robust star formation history and cluster parameter constraints, obtained through color–magnitude diagram analysis of resolved stellar populations, to study Andromeda’s cluster and field populations over the last ∼300 Myr. We measure Γ of 4%–8% for young, 10–100 Myr-old populations in M31. We find that cluster formation efficiency varies systematically across the M31 disk, consistent with variations in mid-plane pressure. These Γ measurements expand the range of well-studied galactic environments, providing precise constraints in an H i-dominated, low-intensity star formation environment. Spatially resolved results from M31 are broadly consistent with previous trends observed on galaxy-integrated scales, where Γ increases with increasing star formation rate surface density (ΣSFR). However, we can explain observed scatter in the relation and attain better agreement between observations and theoretical models if we account for environmental variations in gas depletion time (τdep) when modeling Γ, accounting for the qualitative shift in star formation behavior when transitioning from a H2-dominated to a H i-dominated interstellar medium. We also demonstrate that Γ measurements in high ΣSFR starburst systems are well-explained by τdep-dependent fiducial Γ models. [ABSTRACT FROM AUTHOR]

We present a sample of 11 M31 Cepheids in stellar clusters, derived from the overlap of the Panchromatic Hubble Andromeda Treasury cluster catalog and the Pan-STARRS1 (PS1) disk Cepheid catalog. After identifying the PS1 Cepheids in the Hubble Space Telescope (HST) catalog, we calibrate the PS1 mean magnitudes using the higher resolution HST photometry, revealing up to 1 mag offsets due to crowding effects in the ground-based catalog. We measure ages of the clusters by performing single-age stellar population fits to their color–magnitude diagrams excluding their Cepheids. From these cluster age measurements, we derive an empirical period–age relation which agrees well with the existing literature values. By confirming this relation for M31 Cepheids, we justify its application in high-precision pointwise age estimation across M31. [ABSTRACT FROM AUTHOR]

We examine the radial distributions of stellar populations in the globular cluster (GC) M15, using Hubble Space Telescope/Wide Field Camera 3 (WFC3) photometry of red giants in the nitrogen-sensitive F343N–F555W color. Surprisingly, we find that giants with “primordial” composition (i.e., N abundances similar to those in field stars) are the most centrally concentrated within the WFC3 field. We then combine our WFC3 data with Sloan Digital Sky Survey photometry and find that the trend reverses for radii (3 pc) where the ratio of primordial to N-enhanced giants increases outward, as already found by Lardo et al. The ratio of primordial to enriched stars thus has a U-shaped dependency on radius with a minimum near the half-light radius. N-body simulations show that mass segregation might produce a trend resembling the observed one, but only if the N-enhanced giants are less massive than the primordial giants, which requires extreme He enhancement (). However, such a large difference in Y is incompatible with the negligible optical color differences between primordial and enriched giants, which suggest and thus a difference in turn-off mass of between the different populations. The radial trends in M15 are thus unlikely to be of dynamical origin and presumably reflect initial conditions, a result that challenges all current GC formation scenarios. We note that population gradients in the central regions of GCs remain poorly investigated and may show a more diverse behavior than hitherto thought. [ABSTRACT FROM AUTHOR]

Introduction: During the lockdown of the COVID-19 pandemic in Denmark in March 2020, the trauma Accidents and Emergency (A and E) Department of Odense University Hospital, Denmark, experienced a marked decline in visits. We had the impression that the decline in visits for non-severe injuries was larger than that for severe injuries., Methods: We analysed the incident rate ratio (IRR) between the first month of the lockdown with the IRR recorded in the month leading up to the lockdown. We then compared this IRR with the IRR for the equivalent periods of 2019. The outcomes were: diagnoses (or diagnosis groups), activity during injury (ADI), mechanisms of injury, age group and gender. Secondarily, certain specific diagnoses (or diagnosis groups) were analysed by ADI and mechanism of injury., Results: We observed a significant reduction by 30.6% of all hand injuries in 2020. The non-severe injuries had a significant IRR reduction of 58.7% and the severe injuries a reduction of 15.3%, which was non-significant. The IRR in 2020 was significantly lower in 2020 for the age groups: 0-14, 15-17 and 25-49 years. The relative reduction in IRR was markedly larger for men (40.8%) than for women (22.3%), although this difference was not significant., Conclusion: We observed a greater reduction in non-severe injuries than in severe injuries compared with 2019. Further studies are needed to fully examine the cause of this phenomenon. The reduction may be caused, in part, by a more restrictive attitude towards seeking medical help at a trauma A and E during the first COVID-19 lockdown., Funding: none TRIAL REGISTRATION. not relevant., (Articles published in the DMJ are “open access”. This means that the articles are distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits any non-commercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.)

The legislative process before the adoption of the revised European Union renewable energy directive mobilised various actors around the forest biomass issue in Europe. Which storylines do actors use to discuss and define the sustainability of forest biomass, how are the differences between the existing storylines explained, and can distinct 'discourse coalitions' of actors be observed as following each storyline? These questions are addressed through a discourse analysis to critically evaluate the debate around the utilisation of forest biomass for European renewable energy to identify persistent storylines adopted by discourse coalitions as they communicate their understanding of the issue, and compete to influence the policymaking and public perception. The hypotheses are that there are more than the hypothetical binary arrangement of pro versus anti storylines, and that some actors follow multiple storylines. Locating the methodological approach on the two dimensions; text versus context and critical versus constructivist, this study pays closer attention to context rather than on individual linguistic elements of texts. Regarding the second dimension, this study builds upon constructivist epistemology, being concerned with understanding which truths these storylines produce for their speakers, and their external influences upon alternative storylines and actors. The three storylines presented here represent three competing discourses regarding forest biomass usage in European renewable energy: forestry prioritised, climate focussed and critical. Each of these are promoted by actors aiming to gain discursive hegemony on the issue, both in terms of the impact of their discourse upon EU policy making and in the eyes of the public. Despite the discursive differences created by these deeply held opposing views of what sustainability and nature are and what this means for forest biomass, there were several points where narrative elements overlapped. These can provide insight for developing a more constructive debate on the sustainability of forest biomass., Competing Interests: Søren Larsen have read the journal’s policy and the authors of this manuscript have the following competing interests. Søren Larsen was employed by Danish Energy and Ørsted while working on this paper. Danish Energy is an association of Danish energy utilities, many of which have commercial interest in electricity and heat production from solid biomass. Ørsted is a Danish energy company that is involved in electricity and heat production from solid biomass. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

This study assesses the joint-specific sustained effect of collagenase clostridium histolyticum treatment of Dupuytren disease over a 5-year follow-up period. The study includes 107 consecutive treatments in patients with extension deficits greater than 20° affecting the metacarpophalangeal or proximal interphalangeal joints. Success was defined as no follow-up treatment due to relapse or maintained extension deficit less than 20°. The 5-year estimate of no follow-up treatment was 79% (95% CI: 64-88) for metacarpophalangeal and 49% (95% CI: 26-69) for proximal interphalangeal joints, which was a significant difference (log-rank test, p = 0.0044). For those who did not undergo re-treatment, a non-significant relapse was found for metacarpophalangeal joints and a 65% (34°, 95% CI: 24-46) relapse for proximal interphalangeal joints. We conclude that treating metacarpophalangeal joints with collagenase clostridium histolyticum is effective with acceptable recurrence rates. However, when treating proximal interphalangeal joints with collagenase clostridium histolyticum, patients should be informed of the high risk of recurrence and the greater chance of need for further treatment., Level of Evidence: II.

Background and Objectives: Most telemedicine solutions are proprietary and disease specific which cause a heterogeneous and silo-oriented system landscape with limited interoperability. Solving the interoperability problem would require a strong focus on data integration and standardization in telemedicine infrastructures. Our objective was to suggest a future-proof architecture, that consisted of small loose-coupled modules to allow flexible integration with new and existing services, and the use of international standards to allow high re-usability of modules, and interoperability in the health IT landscape., Methods: We identified core features of our future-proof architecture as the following (1) To provide extended functionality the system should be designed as a core with modules. Database handling and implementation of security protocols are modules, to improve flexibility compared to other frameworks. (2) To ensure loosely coupled modules the system should implement an inversion of control mechanism. (3) A focus on ease of implementation requires the system should use HL7 FHIR (Fast Interoperable Health Resources) as the primary standard because it is based on web-technologies., Results: We evaluated the feasibility of our architecture by developing an open source implementation of the system called ORDS. ORDS is written in TypeScript, and makes use of the Express Framework and HL7 FHIR DSTU2. The code is distributed on GitHub. All modules have been tested unit wise, but end-to-end testing awaits our first clinical example implementations., Conclusions: Our study showed that highly adaptable and yet interoperable core frameworks for telemedicine can be designed and implemented. Future work includes implementation of a clinical use case and evaluation., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Dupuytren disease (DD) is a fibroproliferative disorder of the palmar fasciae causing extension deficit and impaired hand function. Treatment with injection of collagenase clostridium histolyticum (CCH) is a nonsurgical treatment method. The aim of this study was to evaluate the difference in efficiency and recurrence at 12-month follow-up when treating metacarpophalangeal (MP) and proximal interphalangeal (PIP) joints with CCH. None of the patients had received previous treatments of their condition., Methods: This study is a prospective study of a consecutive series of patients with DD presenting with an extension deficit greater than 20° affecting the MP or PIP joint., Results: We found a mean reduction in extension deficit of 47° (91%) for MP joints and 47° (76%) for PIP joints. Full correction (max 5° deficit) was achieved in 76% of MP and 28% of PIP joints. Skin rupture was seen in 34% of treatments. The 1-year relapse rate was 15% for MP and 67% for PIP joints. The reduction in quickDASH score was only statistically significant for MP joints at 1 year. Eighty-one percent of all patients reported being satisfied or very satisfied. No major adverse events were recorded., Conclusion: Excellent results can be achieved in the treatment of MP-joint contractures, whereas the success rate is significantly lower and recurrence rate is greater for PIP joints.

Increased concentrations of dissolved organic carbon (DOC), often labelled "browning", is a current trend in northern, particularly boreal, freshwaters. The browning has been attributed to the recent reduction in sulphate (S) deposition during the last 2 to 3 decades. Over the last century, climate and land use change have also caused an increasing trend in vegetation cover ("greening"), and this terrestrially fixed carbon represents another potential source for export of organic carbon to lakes and rivers. The impact of this greening on the observed browning of lakes and rivers on decadal time scales remains poorly investigated, however. Here, we explore time-series both on water chemistry and catchment vegetation cover (using NDVI as proxy) from 70 Norwegian lakes and catchments over a 30-year period. We show that the increase in terrestrial vegetation as well as temperature and runoff significantly adds to the reduced SO4-deposition as a driver of freshwater DOC concentration. Over extended periods (centuries), climate mediated changes in vegetation cover may cause major browning of northern surface waters, with severe impact on ecosystem productivity and functioning.

The aim of this study was to assess the effect of conservative versus operative treatment for unstable palmar plate disruption in the proximal interphalangeal (PIP) joint of the fingers with respect to preservation of joint stability, mobility, and pain. The study was conducted as a prospective study in which 83 patients were randomly assigned into 2 groups: (1) conservative treatment with a rigid splint for 2 weeks, (2) surgical reattachment of the palmar plate in local anesthesia followed by 2 weeks of immobilization in a plaster cast. Both groups were thereafter treated by taping to the neighboring finger for 3 weeks. With regard to hyperextension instability, stiffness, and pain, there is no significant difference in outcome between patients with traumatic palmar plate lesions and hyperextension instability treated with surgical repair and patients treated conservatively with a splint. We do not recommend primary surgical repair of unstable isolated palmar plate lesions in the proximal interphalangeal joints of the 4 ulnar fingers. Type of study/level of evidence Therapeutic, Level II.

Background: Fast and accurate staging is essential for choosing treatment for non-small-cell lung cancer (NSCLC). The purpose of this randomized study was to evaluate the clinical effect of combined positron-emission tomography and computed tomography (PET-CT) on preoperative staging of NSCLC., Methods: We randomly assigned patients who were referred for preoperative staging of NSCLC to either conventional staging plus PET-CT or conventional staging alone. Patients were followed until death or for at least 12 months. The primary end point was the number of futile thoracotomies, defined as any one of the following: a thoracotomy with the finding of pathologically confirmed mediastinal lymph-node involvement (stage IIIA [N2]), stage IIIB or stage IV disease, or a benign lung lesion; an exploratory thoracotomy; or a thoracotomy in a patient who had recurrent disease or death from any cause within 1 year after randomization., Results: From January 2002 through February 2007, we randomly assigned 98 patients to the PET-CT group and 91 to the conventional-staging group. Mediastinoscopy was performed in 94% of the patients. After PET-CT, 38 patients were classified as having inoperable NSCLC, and after conventional staging, 18 patients were classified thus. Sixty patients in the PET-CT group and 73 in the conventional-staging group underwent thoracotomy (P=0.004). Among these thoracotomies, 21 in the PET-CT group and 38 in the conventional-staging group were futile (P=0.05). The number of justified thoracotomies and survival were similar in the two groups., Conclusions: The use of PET-CT for preoperative staging of NSCLC reduced both the total number of thoracotomies and the number of futile thoracotomies but did not affect overall mortality. (ClinicalTrials.gov number, NCT00867412.), (2009 Massachusetts Medical Society)

A patient presented with volar dislocation of the scaphoid, the diagnosis of which had been missed for two weeks. He was treated with open reduction through a combined volar and dorsal approach with decompression of the median nerve, internal fixation, and a cast for eight weeks. One year postoperatively the functional result was good. A radiograph showed no sign of avascular necrosis.

Objective: The primary objective of the present study was to investigate the safety, tolerability, and pharmacokinetics of a single dose of NN2211, a long-acting glucagon-like peptide 1 (GLP-1) derivative, in healthy male subjects. The secondary objective was to investigate the pharmacodynamics of NN2211., Research Design and Methods: In a double-blind, randomized dose, escalation, placebo-controlled study, healthy male subjects were enrolled at eight consecutive dose levels (1.25, 2.5, 5.0, 10.0, 12.5, 15.0, 17.5, and 20.0 microg/kg) with eight subjects per dose level at a 3:1 active:placebo randomization. After subcutaneous dosing with NN2211, 48-h pharmacokinetic, and 24-h glucose, insulin and glucagon profiles were assessed. In addition, three subjects at each dose level were randomly assigned (one placebo/two active) to an intravenous glucose tolerance test (IVGTT) 9 h after the dose (corresponding to the time to maximal plasma concentration of NN2211)., Results: After subcutaneous administration, the half-life of NN2211 was found to be 11-15 h. Overall, although there were no statistically significant differences compared with placebo in the area under the curve (0-9 h for insulin or glucagon), there was a borderline- significant lowering of glucose levels (P = 0.066). During the IVGTT, there was a statistically significant increase in insulin secretion (P = 0.0002), but there was no significant effect on glucagon levels. Although no significant effect was observed on glucose levels during the IVGTT, there was a dose-dependent increase in the glucose disappearance constant. Whereas no serious adverse events were observed, there was a higher incidence of adverse events after active treatment compared with placebo treatment (notably headache, dizziness, nausea, and vomiting)., Conclusions: This study provides evidence that NN2211 has a pharmacokinetic profile consistent with once-daily dosing in humans.