Using step width to compare locomotor biomechanics between extinct, non-avian theropod dinosaurs and modern obligate bipeds

How extinct, non-avian theropod dinosaurs locomoted is a subject of considerable interest, as is the manner in which it evolved on the line leading to birds. Fossil footprints provide the most direct evidence for answering these questions. In this study, step width—the mediolateral (transverse) distance between successive footfalls—was investigated with respect to speed (stride length) in non-avian theropod trackways of Late Triassic age. Comparable kinematic data were also collected for humans and 11 species of ground-dwelling birds. Permutation tests of the slope on a plot of step width against stride length showed that step width decreased continuously with increasing speed in the extinct theropods (p < 0.001), as well as the five tallest bird species studied (p < 0.01). Humans, by contrast, showed an abrupt decrease in step width at the walk–run transition. In the modern bipeds, these patterns reflect the use of either a discontinuous locomotor repertoire, characterized by distinct gaits (humans), or a continuous locomotor repertoire, where walking smoothly transitions into running (birds). The non-avian theropods are consequently inferred to have had a continuous locomotor repertoire, possibly including grounded running. Thus, features that characterize avian terrestrial locomotion had begun to evolve early in theropod history

Short photoperiod-induced decrease of histamine H3 receptors facilitates activation of hypothalamic neurons in the Siberian Hamster

Nonhibernating seasonal mammals have adapted to temporal changes in food availability through behavioral and physiological mechanisms to store food and energy during times of predictable plenty and conserve energy during predicted shortage. Little is known, however, of the hypothalamic neuronal events that lead to a change in behavior or physiology. Here we show for the first time that a shift from long summer-like to short inter-like photoperiod, which induces physiological adaptation to winter in the Siberian hamster, including a body weight decrease of up to 30%, increases neuronal activity in the dorsomedial region of the arcuate nucleus (dmpARC) assessed by electro physiological patch-clamping recording. Increased neuronal activity in short days is dependent on a photoperiod-driven down-regulation of H3 receptor expression and can be mimicked in long-day dmpARC neurons by the application of the H3 receptor antagonist, clobenproprit. Short-day activation of dmpARC neurons results in increased c-Fos expression. Tract tracing with the trans-synaptic retrograde tracer, pseudorabies virus, delivered into adipose tissue reveals a multisynaptic neuronal sympathetic outflow from dmpARC to white adipose tissue. These data strongly suggest that increased activity of dmpARC neurons, as a consequence of down-regulation of the histamine H3 receptor, contributes to the physiological adaptation of body weight regulation in seasonal photoperiod

Radio Astronomy

Contains research objectives and reports on three research projects.Joint Services Electronics Programs (U. S. Army, U.S. Navy, and U.S. Air Force) under Contract DA 28-043-AMC-02536(E)U. S. Navy (Office of Naval Research) under Contract N00014-67-A-0204-0009National Science Foundation (Grant GP-7046)National Aeronautics and Space Administration (Contract NSR-22-009-120)National Aeronautics and Space Administration (Grant NsG-419

A new look at loop quantum gravity

I describe a possible perspective on the current state of loop quantum gravity, at the light of the developments of the last years. I point out that a theory is now available, having a well-defined background-independent kinematics and a dynamics allowing transition amplitudes to be computed explicitly in different regimes. I underline the fact that the dynamics can be given in terms of a simple vertex function, largely determined by locality, diffeomorphism invariance and local Lorentz invariance. I emphasize the importance of approximations. I list open problems.Comment: 15 pages, 5 figure

Rural Parent\u27s Experiences of Stress and Resilience During the COVID-19 Pandemic and School Closure

The COVID-19 pandemic has generated social and economic disruptions, resulting in cascading effects on the health and well-being of global citizens. However, little research has focused on how COVID-19 has affected rural regions, despite rurality being a critical factor for understanding community impact and response to the pandemic. The purpose of this phenomenological study was to explore the experiences of rural Nebraskan parents with young children during the COVID-19 pandemic and school shutdown, and the strategies they used to support their families during that time. We conducted individual and group interviews with 22 white, non-Hispanic mothers living in rural towns, villages, and farms in the Great Plains region of the United States. Thematic analysis was used to generate the following themes related to pandemic challenges: Impacts on Children’s Education and Development, Impact on Parent’s Work, and Social-emotional Impacts. Additionally, we generated themes related to the ways that rural parents responded to those challenges: Successful Parenting Strategies, Children’s Strategies, Using Community Provided Resources, Finding Unexpected Benefits, and Hope. This study is meaningful because it documented the impact of the COVID-19 pandemic and school shutdown on rural families with young children, and their responses to pandemic-related stressors. Our findings provide further insights into families’ experiences of how COVID-19 affected their lives. Limitations and future directions are also discussed

How do Muslim service users, caregivers, and community members in Malappuram, Kerala, use their faith to address the challenges associated with mental ill health?

Our aim was to explore the role religion and spiritual beliefs play in dealing with the challenges associated with mental ill health among the Muslim community in Malappuram, Kerala. Twenty-four interviews were conducted with patients of Islamic faith diagnosed with a mental health condition (n = 10) in urban (Ponnani) and rural (Vailathur) area of Malappuram, a Muslim majority district in Kerala, their family carers (n = 8) and community members (n = 6). Four key themes were derived, namely (1) Attribution to supernatural factors, (2) Relying on “God’s will”, (3) Prayer, and (4) Traditional healing. Faith was seen to be a prerequisite for any treatment, including modern medicine, to work. Even within a single faith group there can be considerable variation in belief and practice, with more pious participants disapproving of the reliance on local traditional healers and belief systems, highlighting the value of paying attention to the detail of local beliefs and practices

The Lantern Vol. 48, No. 1, December 1981

• While Sipping Scotch and Soda • I Remember • The Apology • Growing • It Seems Like Time Has Stood Still • Zimmerman Encounters Pessimism • Deliverer • Genus Sublime • Yours, Still • The Rising Sun • Person, Valley, Things • It Lay Motionless • Les Parques • Opportunity • The Park - I, II • Another Dimension • Grand Mal • Moments Later • Look Into A Pond • Trust and Dependency • From Foundlings • Drought • Girl at Fence • Campus • Clocking Time • A Letter From Clarence • When Flat Lines • Every Now and Then • Loneliness • Emotion No. 2 • You\u27re Walking • Battle Cries • The Ultimate Feudal Lord • Monologue From A Farther Roomhttps://digitalcommons.ursinus.edu/lantern/1119/thumbnail.jp

Fermions in three-dimensional spinfoam quantum gravity

We study the coupling of massive fermions to the quantum mechanical dynamics of spacetime emerging from the spinfoam approach in three dimensions. We first recall the classical theory before constructing a spinfoam model of quantum gravity coupled to spinors. The technique used is based on a finite expansion in inverse fermion masses leading to the computation of the vacuum to vacuum transition amplitude of the theory. The path integral is derived as a sum over closed fermionic loops wrapping around the spinfoam. The effects of quantum torsion are realised as a modification of the intertwining operators assigned to the edges of the two-complex, in accordance with loop quantum gravity. The creation of non-trivial curvature is modelled by a modification of the pure gravity vertex amplitudes. The appendix contains a review of the geometrical and algebraic structures underlying the classical coupling of fermions to three dimensional gravity.Comment: 40 pages, 3 figures, version accepted for publication in GER

Radio Astronomy

Contains reports on three research projects, with one broken into two subsections.National Aeronautics and Space Administration (Grant NsG-419)National Aeronautics and Space Administration (Contract NSR-22-009-120)Joint Services Electronics Programs (U.S. Army, U.S. Navy, and U.S. Air Force) under Contract DA 28-043-AMC-02536(E

Antibody-mediated inhibition of the FGFR1c isoform induces a catabolic lean state in Siberian hamsters

Hypothalamic tanycytes are considered to function as sensors of peripheral metabolism [1]. To facilitate this role, they express a wide range of receptors, including fibroblast growth factor receptor 1 (FGFR1). Using a monoclonal antibody (IMC-H7) that selectively antagonizes the FGFR1c isoform [2], we investigated possible actions of FGFR1c in a natural animal model of adiposity, the Siberian hamster. Infusion of IMC-H7 into the third ventricle suppressed appetite and increased energy expenditure. Likewise, peripheral treatment with IMC-H7 decreased appetite and body weight and increased energy expenditure and fat oxidation. A greater reduction in body weight and caloric intake was observed in response to IMC-H7 during the long-day fat state as compared to the short-day lean state. This enhanced response to IMC-H7 was also observed in calorically restricted hamsters maintained in long days, suggesting that it is the central photoperiodic state rather than the peripheral adiposity that determines the response to FGFR1c antagonism. Hypothalamic thyroid hormone availability is controlled by deiodinase enzymes (DIO2 and DIO3) expressed in tanycytes and is the key regulator of seasonal cycles of energy balance [3 and 4]. Therefore, we determined the effect of IMC-H7 on hypothalamic expression of these deiodinase enzymes. The reductions in food intake and body weight were always associated with decreased expression of DIO2 in the hypothalamic ependymal cell layer containing tanycytes. These data provide further support for the notion the tanycytes are an important component of the mechanism by which the hypothalamus integrates central and peripheral signals to regulate energy intake and expenditure