MARES, a replicable pipeline and curated reference database for marine eukaryote metabarcoding

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Weakened magnetic braking as the origin of anomalously rapid rotation in old field stars

A knowledge of stellar ages is crucial for our understanding of many astrophysical phenomena, and yet ages can be difficult to determine. As they become older, stars lose mass and angular momentum, resulting in an observed slowdown in surface rotation. The technique of 'gyrochronology' uses the rotation period of a star to calculate its age. However, stars of known age must be used for calibration, and, until recently, the approach was untested for old stars (older than 1 gigayear, Gyr). Rotation periods are now known for stars in an open cluster of intermediate age (NGC 6819; 2.5 Gyr old), and for old field stars whose ages have been determined with asteroseismology. The data for the cluster agree with previous period-age relations, but these relations fail to describe the asteroseismic sample. Here we report stellar evolutionary modelling, and confirm the presence of unexpectedly rapid rotation in stars that are more evolved than the Sun. We demonstrate that models that incorporate dramatically weakened magnetic braking for old stars can---unlike existing models---reproduce both the asteroseismic and the cluster data. Our findings might suggest a fundamental change in the nature of ageing stellar dynamos, with the Sun being close to the critical transition to much weaker magnetized winds. This weakened braking limits the diagnostic power of gyrochronology for those stars that are more than halfway through their main-sequence lifetimes.Comment: 25 pages, 3 figures in main paper, 6 extended data figures, 1 table. Published in Nature, January 2016. Please see https://youtu.be/O6HzYgP5uyc for a video description of the resul

Tongue metastasis as an initial presentation of renal cell carcinoma: a case report and literature review

<p>Abstract</p> <p>Introduction</p> <p>Primary tumour of the kidney metastasizing to the tongue is very unusual and only anecdotal cases have been reported. An exhaustive literature review covering the period from 1911 onwards disclosed 28 cases. Out of those, only 3 cases presented initially with tongue metastases before the diagnosis of primary renal cell carcinoma.</p> <p>The prognosis for patients with lingual metastasis of renal cell carcinoma is poor. Treatment of tongue metastasis is usually palliative and aims to provide patient comfort by means of pain relief and prevention of bleeding and infection. Surgical excision is recommended as the primary treatment with emphasis on preservation of tongue structure and function.</p> <p>Case presentation</p> <p>We report a case of tongue metastasis as an initial presentation of renal cell carcinoma in a 78-year-old man. Initially thought to be primary tongue cancer but on review of his histopathology again, it was diagnosed to be a rare metastasis from kidney cancer.</p> <p>Conclusion</p> <p>Tongue metastasis from renal cell carcinoma is rare and its diagnosis is a challenge. The prognosis of patients with tongue metastasis is poor. Similar to the primary tumours of the tongue, metastatic lesions may be ulcerated or polypoid. Since the tongue is a rare metastatic site, when a lesion is detected, a thorough evaluation to distinguish between metastasis and primary cancer should be made as the management and prognosis vary.</p

Investigating the Therapeutic Potential of a Probiotic in a Rat Model for Infection Following Fracture Fixation

Background: Staphylococcus aureus (S. aureus) is the most common pathogen responsible for osteomyelitis. Objectives: Our objective was to investigate the potential of a probiotic as a treatment for S. aureus-induced infection following fracture fixation in a rat model. Methods: Fifty male Sprague-Dawley rats were assigned to five groups (Control, S. aureus, S. aureus +ceftriaxone, S. aureus + once weekly probiotic, and S. aureus + twice weekly probiotic). Lactobacillus casei subsp. casei (ATCC: 39392) was selected from eight strains of probiotic bacteria with anti-staphylococcal activity. Infection was induced by inoculation with106 colony-forming units (CFU) of S. aureus in a closed femur fracture model stabilized with an intramedullary pin. Three weeks after the surgery, the development of infection and response to the therapy was documented using radiographs, microbiological and histopathological analysis. Results: No bacteria were recovered from rats in the Control group. The analysis of variance revealed a significant difference in the CFU/femur (P < 0.001) and CFU/pin (P = 0.001) across all five treatment groups. When the results were compared, the CFU/femur was significantly lower in the S. aureus + Probiotic twice weekly in comparison with S. aureus (P = 0.008) and the S. aureus + ceftriaxone (P = 0.012) groups. Repeated measure ANOVA to test the radiographic scores during the follow-up time between the intervention groups revealed no significant differences (P = 0.179). Conclusions: Parenteral administration of viable L. casei inhibits S. aureus-induced infection as shown by the bacteriologic analysis, but makes no difference to the radiological union rates. This could be the first step towards developing an effective, biologic adjunctive therapy for the management of osteomyelitis following fracture fixation

Human behaviour in emergency situations: comparisons between aviation and rail domains

This article presents a comparative review of the knowledge base regarding human behaviour in emergencies for both aviation and rail domains. Generic models of human behaviour in emergency situations are introduced and specific attention is then focussed on methods of behaviour prediction, exhibited behaviours in emergencies and methods of aiding evacuation across both modes of transport. Using established knowledge from the aviation domain, it has been possible to make observations and comparisons about the rail domain. Traditionally, the aviation domain has been a major focus of research attention and this is used to inform and interpret the rail domain. By drawing comparisons across these domains for human behaviour in emergency situations, the observations are discussed along with recommendations for future policies/planning for emergencies and future research areas

The Cosmological Constant

This is a review of the physics and cosmology of the cosmological constant. Focusing on recent developments, I present a pedagogical overview of cosmology in the presence of a cosmological constant, observational constraints on its magnitude, and the physics of a small (and potentially nonzero) vacuum energy.Comment: 50 pages. Submitted to Living Reviews in Relativity (http://www.livingreviews.org/), December 199

Environmental drivers of distribution and reef development of the Mediterranean coral Cladocora caespitosa

Cladocora caespitosa is the only Mediterranean scleractinian similar to tropical reef-building corals. While this species is part of the recent fossil history of the Mediterranean Sea, it is currently considered endangered due to its decline during the last decades. Environmental factors affecting the distribution and persistence of extensive bank reefs of this endemic species across its whole geographic range are poorly understood. In this study, we examined the environmental response of C. caespitosa and its main types of assemblages using ecological niche modeling and ordination analysis. We also predicted other suitable areas for the occurrence of the species and assessed the conservation effectiveness of Mediterranean marine protected areas (MPAs) for this coral. We found that phosphate concentration and wave height were factors affecting both the occurrence of this versatile species and the distribution of its extensive bioconstructions in the Mediterranean Sea. A set of factors (diffuse attenuation coefficient, calcite and nitrate concentrations, mean wave height, sea surface temperature, and shape of the coast) likely act as environmental barriers preventing the species from expansion to the Atlantic Ocean and the Black Sea. Uncertainties in our large-scale statistical results and departures from previous physiological and ecological studies are also discussed under an integrative perspective. This study reveals that Mediterranean MPAs encompass eight of the ten banks and 16 of the 21 beds of C. caespitosa. Preservation of water clarity by avoiding phosphate discharges may improve the protection of this emblematic species.Spanish Ministry of Economy and Competitiveness [CTM2014-57949-R]info:eu-repo/semantics/publishedVersio

A prevalence of dynamo-generated magnetic fields in the cores of intermediate-mass stars

Magnetic fields play a part in almost all stages of stellar evolution. Most low-mass stars, including the Sun, show surface fields that are generated by dynamo processes in their convective envelopes. Intermediate-mass stars do not have deep convective envelopes, although 10 per cent exhibit strong surface fields that are presumed to be residuals from the star formation process. These stars do have convective cores that might produce internal magnetic fields, and these fields might survive into later stages of stellar evolution, but information has been limited by our inability to measure the fields below the stellar surface. Here we report the strength of dipolar oscillation modes for a sample of 3,600 red giant stars. About 20 per cent of our sample show mode suppression, by strong magnetic fields in the cores, but this fraction is a strong function of mass. Strong core fields occur only in red giants heavier than 1.1 solar masses, and the occurrence rate is at least 50 per cent for intermediate-mass stars (1.6–2.0 solar masses), indicating that powerful dynamos were very common in the previously convective cores of these stars