FISH OTOLITHS FROM THE LATE MAASTRICHTIAN KEMP CLAY (TEXAS, USA) AND THE EARLY DANIAN CLAYTON FORMATION (ARKANSAS, USA) AND AN ASSESSMENT OF EXTINCTION AND SURVIVAL OF TELEOST LINEAGES ACROSS THE K-PG BOUNDARY BASED ON OTOLITHS

Otolith assemblages have rarely been studied across the K-Pg boundary. The late Maastrichtian Kemp Clay of northeastern Texas and the Fox Hills Formation of North Dakota, and the early Danian Clayton Formation of Arkansas therefore offer new insights into how teleost fishes managed across the K-Pg boundary as reconstructed from their otoliths. The Kemp Clay contains 25 species, with 6 new species and 2 in open nomenclature and the Fox Hills Formation contains 4 species including 1 new species. The two otolith associations constitute the Western Interior Seaway (WIS) community. It contains the earliest unambiguous representatives of the Gadiformes (cods and hakes) and the Heterenchelyidae (mud eels). The WIS community differs significantly from other Maastrichtian otolith assemblages previously studied from Mississippi and Maryland, which constitute the Appalachian community, with only 4 shared species (similarity percentage of 7.3%) between both communities. The difference is interpreted to be related to cold-water influence in the WIS community, which may have still been connected to the Arctic Basin, and to the depostional environment (muddy bottom) in the Kemp Clay.             The Kemp Clay is unusually rich in taxa that survived the end-Cretaceous extinction event and are still present in the Danian of the Clayton Formation, or, as the case may be, in the Danian and Selandian of the boreal northern European community known from Denmark. Approximately 54% of all otolith-based teleost species identified from the Maastrichtian WIS community survived the K-Pg boundary event (versus 11-12% in other communities) and 73% of the genera (versus 40-50% in other communities). The early Danian Clayton Formation contains an impoverished inherited association with 14 species, of which 11 are survivors from late Maastrichtian times, 1 species is new, and 2 remain in open nomenclature. This compares to a significantly higher degree of newly evolved species in only slightly younger faunas from the middle to late Danian and Selandian of Europe indicating an initially slow pace of recovery.             The observed differences in survival and the composition of survived and extinct taxa are discussed in the light of the ongoing discussions concerning the consequences and effects that led to the end-Cretaceous extinction event commonly thought to have been caused by a large meteorite impact. In our assessment, an ‘impact winter’ could have had a major influence on the live cycle of tropical to subtropical fishes while perturbations in the pelagic food web or ocean surface acidification might have had a minor and more selective effect. Overall, teleost fishes were significantly affected by the end-Cretaceous mass extinction, but to a much lesser extent than in many other biota. This study provides more evidence of the importance of Late Cretaceous otolith assemblages in the USA for interpreting teleostean evolution.             The newly described taxa are: Elopothrissus carsonsloani n. sp., Pythonichthys arkansasensis n. sp., Congrophichthus transterminus n. gen., n. sp., Rhynchoconger brettwoodwardi n. sp., Palaeogadus weltoni n. sp., Dakotaichthys hogansoni n. gen., n. sp., and Ampheristus americanus n. sp

Methodological Openness in Business History Research: Looking Afresh at the British Interwar Management Movement

This is the final version. Available on open access from Cambridge University Press via the DOI in this recordMuch thought has been accorded to the evolving nature of business history. It is only relatively recently, however, that attempts have been made to articulate methodological issues in a more epistemologically explicit and reflexive fashion. This article contributes to this burgeoning agenda by examining the methodology underpinning an intensive archival study of the British interwar management movement (1918-1939), a major force in British management education between the wars. We explicate the methodology employed and question what this material tells us about the interwar management movement, in terms of its determination to modernize management, encourage openness between firms, and extend a new spirit of partnership. We show that the interwar management movement was characterized by organized cooperation and methodological openness. Our main contribution is to demonstrate that interpretations themselves can become entrenched and prone to inertia, inviting us to revisit these periodically and, if appropriate, recast them.Economic and Social Research Council (ESRC

HIGHLY DIVERSIFIED LATE CRETACEOUS FISH ASSEMBLAGE REVEALED BY OTOLITHS (RIPLEY FORMATION AND OWL CREEK FORMATION, NORTHEAST MISSISSIPPI, USA)

Bulk sampling and extensive, systematic surface collecting of the Coon Creek Member of the Ripley Formation (early Maastrichtian) at the Blue Springs locality and primarily bulk sampling of the Owl Creek Formation (late Maastrichtian) at the Owl Creek type locality, both in northeast Mississippi, USA, have produced the largest and most highly diversified actinopterygian otolith (ear stone) assemblage described from the Mesozoic of North America. The 3,802 otoliths represent 30 taxa of bony fishes representing at least 22 families. In addition, there were two different morphological types of lapilli, which were not identifiable to species level. The large number of otolith specimens as well as the preservation contributed to the recognition of 4 new genera and 13 new species. The otoliths supplied information regarding the presence of bony fishes not available solely on the basis of osteological remains, and the Late Cretaceous bony fish assemblage at the sites would be underestimated and misinterpreted without an examination of the otoliths. The otoliths also contributed evidence on the evolutionary development of teleosts in North America, especially the diversity of the beryciforms in the Late Cretaceous, and provided indications of the paleoecology during the Maastrichtian. The Ripley Formation (Coon Creek Member) otolith assemblage, which accounted for 3,718 of the specimens, is compared to other Cretaceous otolith assemblages in North America that meet certain criteria (employed bulk-sampling techniques, had well-preserved specimens, and possessed a substantial number of specimens and taxa for analysis). These sites were in Alabama, Maryland, Mississippi (two localities), New Jersey, North Carolina, North Dakota, Tennessee, and Texas. Systematic surface collecting at the Blue Springs locality proved to be very beneficial in supplying otoliths specimens from maturer fishes. Many of the surface-collected otoliths represent older adult fishes that assist with the identification of several forms with greater specificity

Hybrid Gear Preliminary Results-Application of Composites to Dynamic Mechanical Components

Composite spur gears were fabricated and then tested at NASA Glenn Research Center. The composite material served as the web of the gear between the gear teeth and a metallic hub for mounting to the torque-applying shaft. The composite web was bonded only to the inner and outer hexagonal features that were machined from an initially all-metallic aerospace quality spur gear. The Hybrid Gear was tested against an all-steel gear and against a mating Hybrid Gear. As a result of the composite to metal fabrication process used, the concentricity of the gears were reduced from their initial high-precision value. Regardless of the concentricity error, the hybrid gears operated successfully for over 300 million cycles at 10000 rpm and 490 in.*lbs torque. Although the design was not optimized for weight, the composite gears were found to be 20% lighter than the all-steel gears. Free vibration modes and vibration/noise tests were also conduct to compare the vibration and damping characteristic of the Hybrid Gear to all-steel gears. The initial results indicate that this type of hybrid design may have a dramatic effect on drive system weight without sacrificing strength

Point-of-care ultrasonography for the diagnosis of testicular torsion: A practical resident curriculum

Background: Prompt Doppler ultrasonography to aid in diagnosis is often key to managing testicular torsion, but there may be delays in access; a faster, more widely available alternative is point-of-care ultrasonography (POCUS). The purpose of this study was to develop and evaluate a scrotal POCUS curriculum for urology and emergency medicine residents. Methods: Content experts in urology, emergency medicine and diagnostic imaging collaborated in a modified Delphi method to design a practical didactic curriculum for scrotal POCUS for the identification of testicular torsion. Training included 3 online video teaching modules and a 1-hour hands-on teaching session with standardized adult patients. We evaluated participants\u27 competency in scrotal POCUS using a validated scale. We assessed participants\u27 knowledge, comfort and confidence in performing scrotal POCUS before and after the intervention and at 3 months. Results: Twenty-four urology (n = 12) and emergency medicine (n = 12) residents participated in the curriculum. After hands-on practice, 23 participants (96%) were deemed competent at scrotal POCUS. Pre-post testing showed significant improvement in knowledge (mean score 63% v. 80%, p \u3c 0.001), comfort (mean Likert score 0.6 v. 3.6, p \u3c 0.001) and confidence (mean Likert score 1.0 v. 2.1, p \u3c 0.001) after the intervention. These effects were maintained at the 3-month assessment. Conclusion: The scrotal POCUS curriculum was effective and acceptable to both urology and emergency medicine residents. The findings suggest that scrotal POCUS can be learned effectively through a short hands-on session and didactic instruction

A Computational Model of the Development of Separate Representations of Facial Identity and Expression in the Primate Visual System

Experimental studies have provided evidence that the visual processing areas of the primate brain represent facial identity and facial expression within different subpopulations of neurons. For example, in non-human primates there is evidence that cells within the inferior temporal gyrus (TE) respond primarily to facial identity, while cells within the superior temporal sulcus (STS) respond to facial expression. More recently, it has been found that the orbitofrontal cortex (OFC) of non-human primates contains some cells that respond exclusively to changes in facial identity, while other cells respond exclusively to facial expression. How might the primate visual system develop physically separate representations of facial identity and expression given that the visual system is always exposed to simultaneous combinations of facial identity and expression during learning? In this paper, a biologically plausible neural network model, VisNet, of the ventral visual pathway is trained on a set of carefully-designed cartoon faces with different identities and expressions. The VisNet model architecture is composed of a hierarchical series of four Self-Organising Maps (SOMs), with associative learning in the feedforward synaptic connections between successive layers. During learning, the network develops separate clusters of cells that respond exclusively to either facial identity or facial expression. We interpret the performance of the network in terms of the learning properties of SOMs, which are able to exploit the statistical indendependence between facial identity and expression

Seven-year experience of a primary care antiretroviral treatment programme in Khayelitsha, South Africa.

OBJECTIVES: We report on outcomes after 7 years of a community-based antiretroviral therapy (ART) programme in Khayelitsha, South Africa, with death registry linkages to correct for mortality under-ascertainment. DESIGN: This is an observational cohort study. METHODS: Since inception, patient-level clinical data have been prospectively captured on-site into an electronic patient information system. Patients with available civil identification numbers who were lost to follow-up were matched with the national death registry to ascertain their vital status. Corrected mortality estimates weighted these patients to represent all patients lost to follow-up. CD4 cell count outcomes were reported conditioned on continuous virological suppression. RESULTS: Seven thousand, three hundred and twenty-three treatment-naive adults (68% women) started ART between 2001 and 2007, with annual enrolment increasing from 80 in 2001 to 2087 in 2006. Of 9.8% of patients lost to follow-up for at least 6 months, 32.8% had died. Corrected mortality was 20.9% at 5 years (95% confidence interval 17.9-24.3). Mortality fell over time as patients accessed care earlier (median CD4 cell count at enrolment increased from 43 cells/microl in 2001 to 131 cells/microl in 2006). Patients who remained virologically suppressed continued to gain CD4 cells at 5 years (median 22 cells/microl per 6 months). By 5 years, 14.0% of patients had failed virologically and 12.2% had been switched to second-line therapy. CONCLUSION: At a time of considerable debate about future global funding of ART programmes in resource-poor settings, this study has demonstrated substantial and durable clinical benefits for those able to access ART throughout this period, in spite of increasing loss to follow-up