A class of globally analytic hypoelliptic operators on compact Lie groups

We obtain global analytic hypoellipticity for a class of differential operators that can be expressed as a zero-order perturbation of a sum of squares of vector fields with real-analytic coefficients on compact Lie groups. The key conditions are: the vector fields must satisfy H\"ormander's finite type condition; there exists a closed subgroup whose action leaves the vector fields invariant; and the operator must be elliptic in directions transversal to the action of the subgroup. This paves the way for further studies on the regularity of sums of squares on principal fiber bundles.Comment: 11 pages. Feedback and comments are wellcom

Dynamical Measurements of Black Hole Masses in Four Brightest Cluster Galaxies at 100 Mpc

We present stellar kinematics and orbit superposition models for the central regions of four Brightest Cluster Galaxies (BCGs), based upon integral-field spectroscopy at Gemini, Keck, and McDonald Observatories. Our integral-field data span radii from < 100 pc to tens of kpc. We report black hole masses, M_BH, of 2.1 +/- 1.6 x 10^10 M_Sun for NGC 4889, 9.7 + 3.0 - 2.6 x 10^9 M_Sun for NGC 3842, and 1.3 + 0.5 - 0.4 x 10^9 M_Sun for NGC 7768. For NGC 2832 we report an upper limit of M_BH < 9 x 10^9 M_Sun. Stellar orbits near the center of each galaxy are tangentially biased, on comparable spatial scales to the galaxies' photometric cores. We find possible photometric and kinematic evidence for an eccentric torus of stars in NGC 4889, with a radius of nearly 1 kpc. We compare our measurements of M_BH to the predicted black hole masses from various fits to the relations between M_BH and stellar velocity dispersion, luminosity, or stellar mass. The black holes in NGC 4889 and NGC 3842 are significantly more massive than all dispersion-based predictions and most luminosity-based predictions. The black hole in NGC 7768 is consistent with a broader range of predictions.Comment: 24 pages, 18 figures. Accepted for publication in Ap

Euclid preparation. Measuring detailed galaxy morphologies for Euclid with Machine Learning

The Euclid mission is expected to image millions of galaxies with high resolution, providing an extensive dataset to study galaxy evolution. We investigate the application of deep learning to predict the detailed morphologies of galaxies in Euclid using Zoobot a convolutional neural network pretrained with 450000 galaxies from the Galaxy Zoo project. We adapted Zoobot for emulated Euclid images, generated based on Hubble Space Telescope COSMOS images, and with labels provided by volunteers in the Galaxy Zoo: Hubble project. We demonstrate that the trained Zoobot model successfully measures detailed morphology for emulated Euclid images. It effectively predicts whether a galaxy has features and identifies and characterises various features such as spiral arms, clumps, bars, disks, and central bulges. When compared to volunteer classifications Zoobot achieves mean vote fraction deviations of less than 12% and an accuracy above 91% for the confident volunteer classifications across most morphology types. However, the performance varies depending on the specific morphological class. For the global classes such as disk or smooth galaxies, the mean deviations are less than 10%, with only 1000 training galaxies necessary to reach this performance. For more detailed structures and complex tasks like detecting and counting spiral arms or clumps, the deviations are slightly higher, around 12% with 60000 galaxies used for training. In order to enhance the performance on complex morphologies, we anticipate that a larger pool of labelled galaxies is needed, which could be obtained using crowdsourcing. Finally, our findings imply that the model can be effectively adapted to new morphological labels. We demonstrate this adaptability by applying Zoobot to peculiar galaxies. In summary, our trained Zoobot CNN can readily predict morphological catalogues for Euclid images.Comment: 27 pages, 26 figures, 5 tables, submitted to A&

Pedophile, child lover, or minor-attracted person? Attitudes toward labels among people who are sexually attracted to children

The primary label for people who are sexually attracted to children (“pedophile”) is conflated with sexual offending behavior and tainted with stigma. In the present pre-registered mixed-method study, we therefore investigated attitudes and preferences regarding "pedophile/hebephile" and other labels among 286 people who report a stronger or equally strong sexual attraction to prepubescent and pubescent children than to adults. Overall, quantitative data showed acceptance of “pedophile/hebephile” as well as a range of alternative labels in a personal (Labeling Oneself) and a professional context (Being Labeled by Others). “Minor-attracted person” and “pedophile/hebephile” received generally higher support than other terms and appeared to be least divisive across three major online fora. Qualitative data revealed four themes: “Contested self-labels,” “Person-first language and pathologizing sexuality/identity,” “Stigma and shame,” and “Reclaiming the pedophile label.” Our results allow deeper insight into reasons for adopting certain labels over others, as well as difficulties of finding a non-stigmatizing label. We discuss limitations of the study and practical implications for clinical and research contexts.publishedVersio

Secret-keeping in therapy by clients who are sexually attracted to children

Objective This study investigated the reasons why pedohebephilic clients disclose their sexual attraction to children in therapy and the experiences associated with this decision among English-speaking samples. Method: The pre-registered online survey combined (1) quantitative correlational data of self-reported improvement, alliance, therapist reaction to disclosure, and the belief that mandatory reporting laws were in place, and (2) qualitative data about reasons for disclosure or no disclosure as well as perceived consequences. The sample consisted of pedohebephilic people who have been clients in therapy and have disclosed (n = 96) or not disclosed (n = 40). Results: While the disclosure and no disclosure groups did not differ in improvement or beliefs about mandatory reporting, those who had disclosed reported a stronger alliance. Clients who did not perceive the therapist’s reaction as supportive reported less improvement than the no disclosure group. Thematic analysis of qualitative data identified three themes concerning motives for disclosing or not disclosing and a fourth regarding differential impacts of disclosure. Discussion: This study indicates that disclosing pedohebephilia does not in and of itself lead to improvement but is contingent on a therapist’s reaction.publishedVersio

Resumption of Positive-Pressure Ventilation Devices for Obstructive Sleep Apnea following Transsphenoidal Surgery: An Institutional Experience of a Surgical Cohort.

Objectives  Transsphenoidal surgery creates a skull base defect that may cause postoperative cerebrospinal fluid (CSF) leakage or pneumocephalus. This study reviewed the institutional experience of a pituitary center in managing patients who use positive-pressure ventilation (PPV) devices for obstructive sleep apnea (OSA) after transsphenoidal surgery, which risks disturbing the skull base repair. Design  Retrospective review. Setting  Pituitary referral center in a major metropolitan medical center. Methods  PPV was resumed at the discretion of the treatment team based on intraoperative findings and OSA severity. Perioperative complications related to resuming and withholding PPV were recorded. Participants  Transsphenoidal surgery patients with OSA using PPV devices. Main Outcome Measures  Intracranial complications before and after resuming PPV. Results  A total of 42 patients met the study criteria. Intraoperative CSF leakage was encountered and repaired in 20 (48%) patients. Overall, 38 patients resumed PPV (median: 3.5 weeks postsurgery; range: 0.14–52 weeks) and 4 patients did not resume PPV. Postoperatively, no patient experienced CSF leakage or pneumocephalus before or after resuming PPV. Four (10%) patients required temporary nocturnal supplemental oxygen at home, one patient was reintubated after a myocardial infarction, and one patient had a prolonged hospital stay due to chronic obstructive pulmonary disease exacerbation. Conclusions  Resuming PPV use after transsphenoidal surgery did not result in intracranial complications. However, delay in resuming PPV resulted in four patients requiring oxygen at home. We propose a preliminary PPV device management algorithm based on the size of the intraoperative CSF leak to facilitate future studies