Whispering to the Deaf: Communication by a Frog without External Vocal Sac or Tympanum in Noisy Environments

Atelopus franciscus is a diurnal bufonid frog that lives in South-American tropical rain forests. As in many other frogs, males produce calls to defend their territories and attract females. However, this species is a so-called “earless” frog lacking an external tympanum and is thus anatomically deaf. Moreover, A. franciscus has no external vocal sac and lives in a sound constraining environment along river banks where it competes with other calling frogs. Despite these constraints, male A. franciscus reply acoustically to the calls of conspecifics in the field. To resolve this apparent paradox, we studied the vocal apparatus and middle-ear, analysed signal content of the calls, examined sound and signal content propagation in its natural habitat, and performed playback experiments. We show that A. franciscus males can produce only low intensity calls that propagate a short distance (<8 m) as a result of the lack of an external vocal sac. The species-specific coding of the signal is based on the pulse duration, providing a simple coding that is efficient as it allows discrimination from calls of sympatric frogs. Moreover, the signal is redundant and consequently adapted to noisy environments. As such a coding system can be efficient only at short-range, territory holders established themselves at short distances from each other. Finally, we show that the middle-ear of A. franciscus does not present any particular adaptations to compensate for the lack of an external tympanum, suggesting the existence of extra-tympanic pathways for sound propagation

Success of Preoperative Radiotherapy in Inflammatory Breast Cancer with Inadequate Response to Taxane-Based Chemotherapies

Inflammatory breast cancer is a locally-aggressive and highly malignant cancer which often carries a poor prognosis for afflicted patients. Multi-modality treatment is often required, and taxane-based chemotherapy has shown improved outcomes and allowed for the pursuit of mastectomies, which are critical to disease control. Inadequate response to taxane-based chemotherapy indicates aggressive disease, and the role of preoperative radiotherapy for treatment in this patient group and its effects on patient outcomes and toxicity has not been studied. This study evaluates the effectiveness of preoperative radiotherapy on this patient group. Inflammatory breast cancer patients between 2012-2018 who were not deemed appropriate for resection following taxane-based chemotherapy leading to their referral for preoperative radiotherapy were identified. Patient, disease, and pre-surgical treatment characteristics were collected. A statistical analysis of surgical outcomes with regards to conversion to resectability, surgical margins, treatment response, complication rates, and locoregional recurrence was performed. 9 patients received neoadjuvant radiation following their inadequate response to taxane-based chemotherapy. 8 of 9 patients converted to resectable disease, 100% of which achieved R0 mastectomy. Median residual primary disease was 1cm, with a grade 1 toxicity being noted in 1 patient which resolved with conservative management. A single low cervical recurrence was observed 4 years after mastectomy. Based on the results of this study, preoperative radiation should be considered in inflammatory breast cancer patients who do not demonstrate adequate response to taxane-based chemotherapy. Use of preoperative radiotherapy in this patient group may lead to the improvement of patient outcomes and a decrease in treatment toxicity

Cranial Ontogeny in Stegoceras validum (Dinosauria: Pachycephalosauria): A Quantitative Model of Pachycephalosaur Dome Growth and Variation

Historically, studies of pachycephalosaurs have recognized plesiomorphically flat-headed taxa and apomorphically domed taxa. More recently, it has been suggested that the expression of the frontoparietal dome is ontogenetic and derived from a flat-headed juvenile morphology. However, strong evidence to support this hypothesis has been lacking. Here we test this hypothesis in a large, stratigraphically constrained sample of specimens assigned to Stegoceras validum, the best known pachycephalosaur, using multiple independent lines of evidence including conserved morphology of ornamentation, landmark-based allometric analyses of frontoparietal shape, and cranial bone histology. New specimens show that the diagnostic ornamentation of the parietosquamosal bar is conserved throughout the size range of the sample, which links flat-headed specimens to domed S. validum. High-resolution CT scans of three frontoparietals reveal that vascularity decreases with size and document a pattern that is consistent with previously proposed histological changes during growth. Furthermore, aspects of dome shape and size are strongly correlated and indicative of ontogenetic growth. These results are complementary and strongly support the hypothesis that the sample represents a growth series of a single taxon. Cranial dome growth is positively allometric, proceeds from a flat-headed to a domed state, and confirms the synonymy of Ornatotholus browni as a juvenile Stegoceras. This dataset serves as the first detailed model of growth and variation in a pachycephalosaur. Flat-headed juveniles possess three characters (externally open cranial sutures, tuberculate dorsal surface texture, and open supratemporal fenestrae) that are reduced or eliminated during ontogeny. These characters also occur in putative flat-headed taxa, suggesting that they may also represent juveniles of domed taxa. However, open cranial sutures and supratemporal fenestrae are plesiomorphic within Ornithischia, and thus should be expected in the adult stage of a primitive pachycephalosaur. Additional lines of evidence will be needed to resolve the taxonomic validity of flat-headed pachycephalosaur taxa

Out-of-Hospital Surgical Airway Management: Does Scope of Practice Equal Actual Practice?

Introduction: Pennsylvania, among other states, includes surgical airway management, or cricothyrotomy, within the paramedic scope of practice. However, there is scant literature that evaluates paramedic perception of clinical competency in cricothyrotomy. The goal of this project is to assess clinical exposure, education and self-perceived competency of ground paramedics in cricothyrotomy. Methods: Eighty-six paramedics employed by four ground emergency medical services agencies completed a 22-question written survey that assessed surgical airway attempts, training, skills verification, and perceptions about procedural competency. Descriptive statistics were used to evaluate responses. Results: Only 20% (17/86, 95% CI [11-28%]) of paramedics had attempted cricothyrotomy, most (13/17 or 76%, 95% CI [53-90%]) of whom had greater than 10 years experience. Most subjects (63/86 or 73%, 95% CI [64-82%]) did not reply that they are well-trained to perform cricothyrotomy and less than half (34/86 or 40%, 95% CI [30-50%]) felt they could correctly perform cricothyrotomy on their first attempt. Among subjects with five or more years of experience, 39/70 (56%, 95% CI [44-68%]) reported 0-1 hours per year of practical cricothyrotomy training within the last five years. Half of the subjects who were able to recall (40/80, 50% 95% CI [39-61%]) reported having proficiency verification for cricothyrotomy within the past five years. Conclusion: Paramedics surveyed indicated that cricothyrotomy is rarely performed, even among those with years of experience. Many paramedics felt that their training in this area is inadequate and did not feel confident to perform the procedure. Further study to determine whether to modify paramedic scope of practice and/or to develop improved educational and testing methods is warranted

Out-of-Hospital Surgical Airway Management: Does Scope of Practice Equal Actual Practice?

Introduction: Pennsylvania, among other states, includes surgical airway management, or cricothyrotomy, within the paramedic scope of practice. However, there is scant literature that evaluates paramedic perception of clinical competency in cricothyrotomy. The goal of this project is to assess clinical exposure, education and self-perceived competency of ground paramedics in cricothyrotomy.Methods: Eighty-six paramedics employed by four ground emergency medical services agencies completed a 22-question written survey that assessed surgical airway attempts, training, skills verification, and perceptions about procedural competency. Descriptive statistics were used to evaluate responses.Results: Only 20% (17/86, 95% CI [11-28%]) of paramedics had attempted cricothyrotomy, most (13/17 or 76%, 95% CI [53-90%]) of whom had greater than 10 years experience. Most subjects (63/86 or 73%, 95% CI [64-82%]) did not reply that they are well-trained to perform cricothyrotomy and less than half (34/86 or 40%, 95% CI [30-50%]) felt they could correctly perform cricothyrotomy on their first attempt. Among subjects with five or more years of experience, 39/70 (56%, 95% CI [44-68%]) reported 0-1 hours per year of practical cricothyrotomy training within the last five years. Half of the subjects who were able to recall (40/80, 50% 95% CI [39-61%]) reported having proficiency verification for cricothyrotomy within the past five years.Conclusion: Paramedics surveyed indicated that cricothyrotomy is rarely performed, even among those with years of experience. Many paramedics felt that their training in this area is inadequate and did not feel confident to perform the procedure. Further study to determine whether to modify paramedic scope of practice and/or to develop improved educational and testing methods is warranted