1,807 research outputs found

    Globular Cluster Systems in Brightest Cluster Galaxies. III: Beyond Bimodality

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    We present new deep photometry of the rich globular cluster (GC) systems around the Brightest Cluster Galaxies UGC 9799 (Abell 2052) and UGC 10143 (Abell 2147), obtained with the HST ACS and WFC3 cameras. For comparison, we also present new reductions of similar HST/ACS data for the Coma supergiants NGC 4874 and 4889. All four of these galaxies have huge cluster populations (to the radial limits of our data, comprising from 12000 to 23000 clusters per galaxy). The metallicity distribution functions (MDFs) of the GCs can still be matched by a bimodal-Gaussian form where the metal-rich and metal-poor modes are separated by ~0.8 dex, but the internal dispersions of each mode are so large that the total MDF becomes very broad and nearly continuous from [Fe/H] = -2.4 to Solar. There are, however, significant differences between galaxies in the relative numbers of \emph{metal-rich} clusters, suggesting that they underwent significantly different histories of mergers with massive, gas-rich halos. Lastly, the proportion of metal-poor GCs rises especially rapidly outside projected radii R > 4 R_eff, suggesting the importance of accreted dwarf satellites in the outer halo. Comprehensive models for the formation of GCs as part of the hierarchical formation of their parent galaxies will be needed to trace the systematic change in structure of the MDF with galaxy mass, from the distinctly bimodal form in smaller galaxies up to the broad continuum that we see in the very largest systems.Comment: In press for Astrophysical Journa

    Autonomous Service Drones for Multimodal Detection and Monitoring of Archaeological Sites

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    Constant detection and monitoring of archaeological sites and objects have always been an important national goal for many countries. The early identification of changes is crucial to preventive conservation. Archaeologists have always considered using service drones to automate collecting data on and below the ground surface of archaeological sites, with cost and technical barriers being the main hurdles against the wide-scale deployment. Advances in thermal imaging, depth imaging, drones, and artificial intelligence have driven the cost down and improved the quality and volume of data collected and processed. This paper proposes an end-to-end framework for archaeological sites detection and monitoring using autonomous service drones. We mount RGB, depth, and thermal cameras on an autonomous drone for low-altitude data acquisition. To align and aggregate collected images, we propose two-stage multimodal depth-to-RGB and thermal-to-RGB mosaicking algorithms. We then apply detection algorithms to the stitched images to identify change regions and design a user interface to monitor these regions over time. Our results show we can create overlays of aligned thermal and depth data on RGB mosaics of archaeological sites. We tested our change detection algorithm and found it has a root mean square error of 0.04. To validate the proposed framework, we tested our thermal image stitching pipeline against state-of-the-art commercial software. We cost-effectively replicated its functionality while adding a new depth-based modality and created a user interface for temporally monitoring changes in multimodal views of archaeological sites

    The advantage of sleeve lobectomy over pneumonectomy

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    Answer to Dr. Ludwig about lower sleeve lobectomy, the so-called “Y” sleeve

    adjuvant mitotane for adrenocortical cancer working through uncertainty

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    The Journal of Clinical Endocrinology & Metabolism recently published a commentary by Huang and Fojo (1) offering a skeptical view on the efficacy of mitotane as an adjunctive postsurgical measure in patients with adrenocortical cancer (ACC). Their commentary focused on outlining the limitations of our recent study which indicated that adjuvant mitotane may prolong recurrence-free survival (RFS) in patients with radically resected ACC (2). However, we do not agree with several of their conclusions and believe that it is of interest to present our view for a balanced and comprehensive coverage of this important matter. Inprinciple,weagreewithHuangandFojothatourstudysuffers from the important limitation of a retrospective analysis; thus our investigation should be considered as hypothesis generating and certainly does not provide conclusive evidence. This problem has been clearly acknowledged in the paper, and we cautiously concluded that our study should renew interest in adjuvant therapy, whereas prospective, randomized trials will be needed to confirm the efficacyof adjuvantmitotane treatment (2).However, the rarity of ACC precluded organization of a randomized trial either in an adjuvantsettingor inpatientswithadvancedACC(3).Nonetheless, mitotane has been used for treating patients with ACC since the 1960s and is the only drug approved for ACC by the U.S. Food and Drug Administration and the European Medicines Evaluation Agency (4). In this scenario, a study including all consecutive patients treated postoperatively with mitotane in some centers and all consecutive patients left untreated after operation in other centers is thebestway toobtainexplorativedataon theefficacyofadjuvant mitotane, provided that the two groups are comparable. In our study, in fact, mitotane was recommended on the basis of the treatmentpolicyof thecenter, independentof thecharacteristicsofeither the tumorsor thepatients, and this is amajoradvantageminimizing selection bias as compared with other studies that had less clear treatment assignments (5). The major criticism of Huang and Fojo (1) is that we did not demonstrate any benefit on overall survival (OS) for patients treated adjuvantly. However, this is not correct because the hazard ratio of death of the German cohort of nontreated patients was nonsignificantly higher than mitotane-treated patients in univariate analysis, but the difference became significant in multivariate analysis after adjusting for imbalances in prognostic factors (the German cohort included more patients with stage I and II ACC than the Italian cohort of mitotane-treated patients). Even when we accept that the effect of adjuvant mitotane on OS was less impressive than on RFS, we disagree that prolonging a disease-free status is not a clinically meaningful objective even without extending significantly duration of life. In addition, there is a long-standing debate on the most appropriate endpoint for adjuvant trials, and both OS and RFS have been suggested. Analysis of RFS has the advantage of needing a shorter follow-up and being directly related to the treatment tested. The most important disadvantage of RFS is its close relationship to the frequency and quality of evaluation. Bias in follow-up or ascertainment of outcome in observational retrospective series is well recognized, and we have acknowledged this potential limit of our study. However, the follow-up procedures were highly comparable among the different centers and included imaging evaluation of the chest and abdomen every 6 months until disease progression or the end of the study period (2). Even if survival has to be considered as the reference end-point, it may not be a direct result of the study drug because it may be strongly influenced by subsequent treatments and oncologists are increasingly considering RFS as a valid surrogate for OS (6). However, this relationship has never been demonstrated specifically in ACC patients. Another criticism is derived from an ill-conceived reanalysis of our data. Huang and Fojo (1) aimed at demonstrating that the time interval between ACC recurrence and death is higher in patients treated adjuvantly than patients left untreated after surgery. Thus, they assumed important differences in tumor biology of the different cohorts. This conclusion comes from subtracting median time to recurrence from median survival observed in th

    Sudden cardiac death after robbery: Homicide or natural death?

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    Tako-Tsubo is one of a number of rare acquired cardiomyopathies that are characterized by left ventricular dyskinesia and symptomatology typical of acute myocardial infarction (AMI). The most important feature is that the clinical features are triggered by a severe physical or emotional stress. The authors describe the story of a woman, who was brutally assaulted by two men during a house robbery and died from sudden heart failure 8 hours later, after being taken to hospital. External examination revealed no macroscopic alteration of the inner organs, whereas microscopy showed contraction bands with myocardial necrosis, subendocardial and interstitial neutrophil infiltration and fibrosis. These findings were consistent with death due to stress cardiomyopathy even in the absence of previous heart disease. The robbers were convicted of homicide and sentenced to eighteen years in prison

    Interprofessional clinical placement involving speech pathology and counselling psychology

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    This paper examines the interprofessional learning of a speech pathology and counselling psychology student in an interprofessional placement within an institution of the Department of Corrective Services in Perth, Western Australia. The institution is a pre-release centre that promotes rehabilitation and community reintegration in which up to six women are able to have their children, aged 0–4 years of age, live with them. The students provided a program to the mothers to facilitate development of a healthy mother–child relationship and the children’s communication development. This paper utilised qualitative descriptive analysis to explore two examples of student learning and found perceived growth in the students’ clinical skills, their understanding of the other profession and the concept of interprofessional collaboration. While students experience growth in a range of placements, the journey described in this paper is unusual in both the nature of the student collaboration and the placement itself. The research highlights the importance of joint clinical placements in the development of interprofessional collaborative relationships

    Interprofessional clinical placement involving speech pathology and counselling psychology

    Get PDF
    This paper examines the interprofessional learning of a speech pathology and counselling psychology student in an interprofessional placement within an institution of the Department of Corrective Services in Perth, Western Australia. The institution is a pre-release centre that promotes rehabilitation and community reintegration in which up to six women are able to have their children, aged 0–4 years of age, live with them. The students provided a program to the mothers to facilitate development of a healthy mother–child relationship and the children’s communication development. This paper utilised qualitative descriptive analysis to explore two examples of student learning and found perceived growth in the students’ clinical skills, their understanding of the other profession and the concept of interprofessional collaboration. While students experience growth in a range of placements, the journey described in this paper is unusual in both the nature of the student collaboration and the placement itself. The research highlights the importance of joint clinical placements in the development of interprofessional collaborative relationships

    Amount of therapy matters in very early aphasia rehabilitation after stroke: A clinical prognostic model

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    Background and Aim The effects of very early aphasia therapy on recovery are equivocal. This article examines predictors of very early aphasia recovery through statistical modeling. Methods This study involved a secondary analysis of merged data from two randomized, single-blind trials conducted in Australian acute and subacute hospitals. Study 1 (n = 59) compared daily therapy to usual ward care for up to 4 weeks poststroke in patients with moderate to severe aphasia. Study 2 (n = 20) compared daily group therapy to daily individual therapy for 20 1-hour sessions over 5 weeks, in patients with mild to severe aphasia. The primary outcome measure was the Western Aphasia Battery Aphasia Quotient (AQ) at therapy completion. This analysis used regression modeling to examine the effects of age, baseline AQ and baseline modified Rankin Scale (mRS), average therapy amount, therapy intensity, and number of therapy sessions on aphasia recovery. Results Baseline AQ (p = 0.047), average therapy amount (p = 0.030), and baseline mRS (p = 0.043) were significant predictors in the final regression model, which explained 30% (p < 0.001) of variance in aphasia recovery. Conclusion The amount of very early aphasia therapy could significantly affect communication outcomes at 4 to 5 weeks poststroke. Further studies should include amount of therapy provided to enhance reliability of prognostic modeling in aphasia recovery. © 2013 by Thieme Medical Publishers, Inc
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