Unheard voices of democracy: implications for leaders regarding high school students' perceptions of school safety measures

This phenomenological study documented junior and senior's perceptions of their rights, surveillance cameras, and School Resource Officers in school environments. Participants included 109 seniors and 47 juniors from an urban, a suburban, and a rural district. Mixed-methods design allowed triangulation of data between 15 Likert-scale quantitative15 open-ended qualitative survey items, and focus groups. Survey and interview responses were coded with an ethno-methodological approach. Parts one and two of the study revealed three themes: Treated Unfairly, Marginalized, and Disenfranchised. Consistency existed between students' perceptions of their rights while at school and the schools' use of surveillance cameras. The third section revealed students felt safer because districts employed School Resource Officers. Vague use of the word safety in survey items was problematic. Study informed school leaders of impact of social justice theories on school cultures

Extreme Cranial Ontogeny in the Upper Cretaceous Dinosaur Pachycephalosaurus

BACKGROUND: Extended neoteny and late stage allometric growth increase morphological disparity between growth stages in at least some dinosaurs. Coupled with relatively low dinosaur density in the Upper Cretaceous of North America, ontogenetic transformational representatives are often difficult to distinguish. For example, many hadrosaurids previously reported to represent relatively small lambeosaurine species were demonstrated to be juveniles of the larger taxa. Marginocephalians (pachycephalosaurids + ceratopsids) undergo comparable and extreme cranial morphological change during ontogeny. METHODOLOGY/PRINCIPAL FINDINGS: Cranial histology, morphology and computer tomography reveal patterns of internal skull development that show the purported diagnostic characters for the pachycephalosaurids Dracorex hogwartsia and Stygimoloch spinifer are ontogenetically derived features. Coronal histological sections of the frontoparietal dome of an adult Pachycephalosaurus wyomingensis reveal a dense structure composed of metaplastic bone with a variety of extremely fibrous and acellular tissue. Coronal histological sections and computer tomography of a skull and frontoparietal dome of Stygimoloch spinifer reveal an open intrafrontal suture indicative of a subadult stage of development. These dinosaurs employed metaplasia to rapidly grow and change the size and shape of their horns, cranial ornaments and frontoparietal domes, resulting in extreme cranial alterations during late stages of growth. We propose that Dracorex hogwartsia, Stygimoloch spinifer and Pachycephalosaurus wyomingensis are the same taxon and represent an ontogenetic series united by shared morphology and increasing skull length. CONCLUSIONS/SIGNIFICANCE: Dracorex hogwartsia (juvenile) and Stygimoloch spinifer (subadult) are reinterpreted as younger growth stages of Pachycephalosaurus wyomingensis (adult). This synonymy reduces the number of pachycephalosaurid taxa from the Upper Cretaceous of North America and demonstrates the importance of cranial ontogeny in evaluating dinosaur diversity and taxonomy. These growth stages reflect a continuum rather than specific developmental steps defined by "known" terminal morphologies

Donepezil Effects on Mood in Patients with Schizophrenia and Schizoaffective Disorder

Donepezil, 5 mg/d for 6 wk then 10 mg/d for 6 wk, and placebo daily for 12 wk in a double-blind cross-over paradigm, was added to the therapeutic regimen of 13 patients with schizophrenia or schizoaffective disorders, clinically stable on atypical antipsychotic medications. Patients had varying degrees of depressive symptoms, ranging from no depression to clinically significant depression. There was no worsening or induction of depression in individual patients or the group as a whole. In addition there was a statistically significant antidepressant effect in the group as a whole during the donepezil condition and a clinically significant antidepressant effect in the patients with clinically significant depressive symptoms, although there were not enough depressed patients in the group to conclude that donepezil may have antidepressant effects. Thus, in this study, donepezil did not induce or worsen depressive symptoms in schizophrenic and schizoaffective disorder patients

Hunting planets and observing disks with the JWST NIRCam coronagraph

The expected stable point spread function, wide field of view, and sensitivity of the NIRCam instrument on the James Webb Space Telescope (JWST) will allow a simple, classical Lyot coronagraph to detect warm Jovian-mass companions orbiting young stars within 150 pc as well as cool Jupiters around the nearest low-mass stars. The coronagraph can also be used to study protostellar and debris disks. At λ = 4.5 μm, where young planets are particularly bright relative to their stars, and at separations beyond ~0.5 arcseconds, the low space background gives JWST significant advantages over ground-based telescopes equipped with adaptive optics. We discuss the scientific capabilities of the NIRCam coronagraph, describe the technical features of the instrument, and present end-to-end simulations of coronagraphic observations of planets and circumstellar disks

Common Avian Infection Plagued the Tyrant Dinosaurs

Abstract Background: Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name 'Sue') has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids

The Lantern Vol. 19, No. 3, Summer 1951

• Up in the Air • On Considering a Wallet\u27s State of Emptiness • You Came from Heaven • If At First • Memory of Winter Mornings • The Night We All Got Drunk • Composer Thomas Waller Enters into Heaven • Elegy in Times Square • To Spring • The Cliff of Morality • An Evening Drive • Liberty • Begone • Limerick with a Leer • Two Allusive Limerickshttps://digitalcommons.ursinus.edu/lantern/1054/thumbnail.jp

Avian tail ontogeny, pygostyle formation, and interpretation of juvenile Mesozoic specimens

The avian tail played a critical role in the evolutionary transition from long- to short-tailed birds, yet its ontogeny in extant birds has largely been ignored. This deficit has hampered efforts to effectively identify intermediate species during the Mesozoic transition to short tails. Here we show that fusion of distal vertebrae into the pygostyle structure does not occur in extant birds until near skeletal maturity, and mineralization of vertebral processes also occurs long after hatching. Evidence for post-hatching pygostyle formation is also demonstrated in two Cretaceous specimens, a juvenile enantiornithine and a subadult basal ornithuromorph. These findings call for reinterpretations of Zhongornis haoae, a Cretaceous bird hypothesized to be an intermediate in the long- to short-tailed bird transition, and of the recently discovered coelurosaur tail embedded in amber. Zhongornis, as a juvenile, may not yet have formed a pygostyle, and the amber-embedded tail specimen is reinterpreted as possibly avian. Analyses of relative pygostyle lengths in extant and Cretaceous birds suggests the number of vertebrae incorporated into the pygostyle has varied considerably, further complicating the interpretation of potential transitional species. In addition, this analysis of avian tail development reveals the generation and loss of intervertebral discs in the pygostyle, vertebral bodies derived from different kinds of cartilage, and alternative modes of caudal vertebral process morphogenesis in birds. These findings demonstrate that avian tail ontogeny is a crucial parameter specifically for the interpretation of Mesozoic specimens, and generally for insights into vertebrae formation

‘Nedoceratops’: An Example of a Transitional Morphology

Background: The holotype and only specimen of the chasmosaurine ceratopsid dinosaur ‘Nedoceratops hatcheri ’ has been the source of considerable taxonomic debate since its initial description. At times it has been referred to its own genus while at others it has been considered synonymous with the contemporaneous chasmosaurine Triceratops. Most recently, the debate has focused on whether the specimen represents an intermediate ontogenetic stage between typical young adult Triceratops and the proposed mature morphology, which was previously considered to represent a distinct genus, ‘Torosaurus’. Methodology/Principal Findings: The only specimen of ‘Nedoceratops hatcheri ’ was examined and the proposed diagnostic features of this taxon were compared with other chasmosaurine ceratopsids. Every suggested autapomorphy of ‘Nedoceratops ’ is found in specimens of Triceratops. In this study, Triceratops includes the adult ‘Torosaurus ’ morphology. The small parietal fenestra and elongate squamosals of Nedoceratops are consistent with a transition from a short, solid parietalsquamosal frill to an expanded, fenestrated condition. Objections to this hypothesis regarding the number of epiossifications of the frill and alternations of bone surface texture were explored through a combination of comparative osteology and osteohistology. The synonymy of the three taxa was further supported by these investigations. Conclusions/Significance: The Triceratops, ‘Torosaurus’, and ‘Nedoceratops ’ morphologies represent ontogenetic variatio

The Mass and Structure of the Pleiades Star Cluster from 2MASS

We present the results of a large scale search for new members of the Pleiades star cluster using 2MASS near-infrared photometry and proper motions derived from POSS plates digitized by the USNO PMM program. The search extends to a 10 degree radius around the cluster, well beyond the presumed tidal radius, to a limiting magnitude of R ~ 20, corresponding to ~ 0.07 M_sun at the distance and age of the Pleiades. Multi-object spectroscopy for 528 candidates verifies that the search was extremely effective at detecting cluster stars in the 1 - 0.1 M_sun mass range using the distribution of H_alpha emission strengths as an estimate of sample contamination by field stars. When combined with previously identified, higher mass stars, this search provides a sensitive measurement of the stellar mass function and dynamical structure of the Pleiades. The degree of tidal elongation of the halo agrees well with current N body simulation results. Tidal truncation affects masses below ~ 1 M_sun. The cluster contains a total mass ~ 800 M_sun. Evidence for a flatter mass function in the core than in the halo indicates the depletion of stars in the core with mass less than ~ 0.5 M_sun, relative to stars with mass \~1 - 0.5 M_sun, and implies a preference for very low mass objects to populate the halo or escape. The overall mass function is best fitted with a lognormal form that becomes flat at ~ 0.1 M_sun. Whether sufficient dynamical evaporation has occurred to detectably flatten the initial mass function, via preferential escape of very low mass stars and brown dwarfs, is undetermined, pending better membership information for stars at large radial distances.Comment: 19 pages, 14 figures, 2 tables, accepted by AJ, to appear April 200