Thermodynamic Stability of Sn4, Sn5, Sn6, and Sn7 Clusters by Knudsen Cell Mass Spectrometry

The Knudsen cell mass spectrometric method has been employed to measure the partial pressures of Sn[sub n] (n=1-7) under equilibrium conditions above liquid tin or a tin-gold alloy, contained in a graphite Knudsen cell. From the all-gas analyzed equilibria the following atomization enthalpies Δ[sub a]H[sub 0][sup °](Sn[sub n]), and enthalpies of formation, Δ[sub f]H[sub 298.15][sup °](Sn[sub n]), in kJ mol-1, have been obtained: Sn[sub 4], 750.2±14 and 450.6±14; Sn[sub 5], 990.2±22 and 512.3±22; Sn[sub 6], 1349.7±28 and 452.8±28; Sn[sub 7], 1644.2±37 and 460.0±37. The atomization energies are compared with available theoretical values

New Protocetid Whale from the Middle Eocene of Pakistan: Birth on Land, Precocial Development, and Sexual Dimorphism

BACKGROUND: Protocetidae are middle Eocene (49-37 Ma) archaeocete predators ancestral to later whales. They are found in marine sedimentary rocks, but retain four legs and were not yet fully aquatic. Protocetids have been interpreted as amphibious, feeding in the sea but returning to land to rest. METHODOLOGY/PRINCIPAL FINDINGS: Two adult skeletons of a new 2.6 meter long protocetid, Maiacetus inuus, are described from the early middle Eocene Habib Rahi Formation of Pakistan. M. inuus differs from contemporary archaic whales in having a fused mandibular symphysis, distinctive astragalus bones in the ankle, and a less hind-limb dominated postcranial skeleton. One adult skeleton is female and bears the skull and partial skeleton of a single large near-term fetus. The fetal skeleton is positioned for head-first delivery, which typifies land mammals but not extant whales, evidence that birth took place on land. The fetal skeleton has permanent first molars well mineralized, which indicates precocial development at birth. Precocial development, with attendant size and mobility, were as critical for survival of a neonate at the land-sea interface in the Eocene as they are today. The second adult skeleton is the most complete known for a protocetid. The vertebral column, preserved in articulation, has 7 cervicals, 13 thoracics, 6 lumbars, 4 sacrals, and 21 caudals. All four limbs are preserved with hands and feet. This adult is 12% larger in linear dimensions than the female skeleton, on average, has canine teeth that are 20% larger, and is interpreted as male. Moderate sexual dimorphism indicates limited male-male competition during breeding, which in turn suggests little aggregation of food or shelter in the environment inhabited by protocetids. CONCLUSIONS/SIGNIFICANCE: Discovery of a near-term fetus positioned for head-first delivery provides important evidence that early protocetid whales gave birth on land. This is consistent with skeletal morphology enabling Maiacetus to support its weight on land and corroborates previous ideas that protocetids were amphibious. Specimens this complete are virtual 'Rosetta stones' providing insight into functional capabilities and life history of extinct animals that cannot be gained any other way

Counseling Update: A Flexible Monitoring Method for the Client and Practitioner

Recent years have seen a number of articles questioning both the utility and practicality of single-case designs. The authors propose a flexible monitoring method for practice evaluation. The proposed method is presented as a dynamic model, one that utilizes the existing evaluative procedures of the practitioner. This flexible method is proposed within the general outlines of developmental research. It is proposed as a method designed to lead practitioners toward an empirical model of practice. Some case examples are provided to substantiate the utility and value of the model.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68429/2/10.1177_104973159300300203.pd

Evidence of strong stabilizing effects on the evolution of boreoeutherian (Mammalia) dental proportions.

The dentition is an extremely important organ in mammals with variation in timing and sequence of eruption, crown morphology, and tooth size enabling a range of behavioral, dietary, and functional adaptations across the class. Within this suite of variable mammalian dental phenotypes, relative sizes of teeth reflect variation in the underlying genetic and developmental mechanisms. Two ratios of postcanine tooth lengths capture the relative size of premolars to molars (premolar-molar module, PMM), and among the three molars (molar module component, MMC), and are known to be heritable, independent of body size, and to vary significantly across primates. Here, we explore how these dental traits vary across mammals more broadly, focusing on terrestrial taxa in the clade of Boreoeutheria (Euarchontoglires and Laurasiatheria). We measured the postcanine teeth of N = 1,523 boreoeutherian mammals spanning six orders, 14 families, 36 genera, and 49 species to test hypotheses about associations between dental proportions and phylogenetic relatedness, diet, and life history in mammals. Boreoeutherian postcanine dental proportions sampled in this study carry conserved phylogenetic signal and are not associated with variation in diet. The incorporation of paleontological data provides further evidence that dental proportions may be slower to change than is dietary specialization. These results have implications for our understanding of dental variation and dietary adaptation in mammals

Supporting people with aphasia to ‘settle into a new way to be’: speech and language therapists’ views on providing psychosocial support

Background: People with aphasia are at risk of becoming depressed and isolated. On-line surveys have found that the majority of Speech and Language Therapists (SLTs) lack confidence in addressing the psychological needs of people with aphasia. Aims: To explore how SLTs conceptualise the scope of their role; barriers and facilitators to SLTs addressing psychosocial needs; and SLTs’ experiences of specialist training and support, and working with mental health professionals (MHPs). Methods and procedures: Focus groups conducted in stroke healthcare settings. Purposive sampling was used in selecting sites so as to capture a range of experiences. Results were analysed using Framework Analysis. Outcomes and Results: Twenty-three SLTs took part in six focus groups. Participants’ psychosocial work included counselling-type interactions, psychoeducation, working with families, facilitating peer support, and training other healthcare professionals. There was a lack of consensus on the scope of the SLT role. Many expressed a sense of conflict, both perceiving it as valuable to spend time addressing psychological well-being, while simultaneously feeling uneasy if they deviated from ‘direct SLT’ work. Barriers to addressing psychosocial wellbeing were: emotionally challenging nature of this work, particularly for those who felt unsupported; caseload and time pressures; attitude of senior managers and commissioners; difficulties measuring and documenting more ‘fluid’ psychosocial work; and the complexity of needs and backgrounds of some patients. Enabling factors were: specialist on-going support; peer support from colleagues; experience; support of management; and personal belief. Specialist training was valued. It changed how participants viewed the therapist-client relationship (more client-led); the assessment and goal setting process; and gave them more confidence to acknowledge client emotions. However, many felt that there was a need for on-going specialist advice, and to be able to see approaches modelled for this client group. In terms of mental health professionals (MHPs), a subset of stroke specialist clinical psychologists worked directly with people with marked aphasia and families, as well as supporting the multidisciplinary team to provide holistic care. However, a main theme was that participants perceived many MHPs did not consider people with aphasia as ‘appropriate candidates’ for psychological input. Conclusions and Implications: All participants cared about the emotional well-being of their clients; however, they identified a number of barriers to people with aphasia receiving appropriate psychological support. A cultural shift, whereby psychological care for people with aphasia is seen as valuable, feasible and necessary, delivered collaboratively by SLTs, MHPs and the wider team, may improve services

Evidence for a Grooming Claw in a North American Adapiform Primate: Implications for Anthropoid Origins

Among fossil primates, the Eocene adapiforms have been suggested as the closest relatives of living anthropoids (monkeys, apes, and humans). Central to this argument is the form of the second pedal digit. Extant strepsirrhines and tarsiers possess a grooming claw on this digit, while most anthropoids have a nail. While controversial, the possible presence of a nail in certain European adapiforms has been considered evidence for anthropoid affinities. Skeletons preserved well enough to test this idea have been lacking for North American adapiforms. Here, we document and quantitatively analyze, for the first time, a dentally associated skeleton of Notharctus tenebrosus from the early Eocene of Wyoming that preserves the complete bones of digit II in semi-articulation. Utilizing twelve shape variables, we compare the distal phalanges of Notharctus tenebrosus to those of extant primates that bear nails (n = 21), tegulae (n = 4), and grooming claws (n = 10), and those of non-primates that bear claws (n = 7). Quantitative analyses demonstrate that Notharctus tenebrosus possessed a grooming claw with a surprisingly well-developed apical tuft on its second pedal digit. The presence of a wide apical tuft on the pedal digit II of Notharctus tenebrosus may reflect intermediate morphology between a typical grooming claw and a nail, which is consistent with the recent hypothesis that loss of a grooming claw occurred in a clade containing adapiforms (e.g. Darwinius masillae) and anthropoids. However, a cladistic analysis including newly documented morphologies and thorough representation of characters acknowledged to have states constituting strepsirrhine, haplorhine, and anthropoid synapomorphies groups Notharctus tenebrosus and Darwinius masillae with extant strepsirrhines rather than haplorhines suggesting that the form of pedal digit II reflects substantial homoplasy during the course of early primate evolution

The Evolution of Bat Vestibular Systems in the Face of Potential Antagonistic Selection Pressures for Flight and Echolocation

PMCID: PMC3634842This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Epistemic insights: Contemplating tensions between policy influences and creativity in school science

Creativity and the way it could be supported in schools is understood differently by policy makers, practitioners and scientists. This article reviews, with a chronological lens, the development of policies that include teaching creativity and teaching for creativity. The epistemic tensions between the intentions of government and the nature of creativity as it emerges in learning or scientific work is introduced and reflected upon. There have been more than nine key educational policies that have been introduced over the last 50 years. Each of these are considered in this article and related to the ways that creativity is understood and expected to be taught, supported or enacted in schools by policy makers. In light of the need to support creativity as a key twenty‐first‐century skill, to ultimately enable current students (who will become the next generation of scientists) to develop the capabilities to address global concerns, this article highlights issues related to this issue. Epistemic insights are offered that relate to the development of aspects of creativity, including questioning, developing alternate ideas, ‘seeing’ things differently, innovation, curiosity, problem solving and evaluating. The ways that policy related to creativity in science appears not to recognise how creativity can be reified in these ways in schools suggests the need for rapid review, especially in light of the upcoming international creativity tests in 2021

Body Shape and Life Style of the Extinct Balearic Dormouse Hypnomys (Rodentia, Gliridae): New Evidence from the Study of Associated Skeletons

Hypnomys is a genus of Gliridae (Rodentia) that occurred in the Balearic Islands until Late Holocene. Recent finding of a complete skeleton of the chronospecies H. morpheus (Late Pleistocene-Early Holocene) and two articulated skeletons of H. cf. onicensis (Late Pliocene) allowed the inference of body size and the calculation of several postcranial indexes. We also performed a Factorial Discriminant Analysis (FDA) in order to evaluate locomotory behaviour and body shape of the taxa. Using allometric models based on skull and tooth measurements, we calculated a body weight between 173 and 284 g for H. morpheus, and direct measurements of articulated skeletons yielded a Head and Body Length (HBL) of 179 mm and a Total Body Length of 295 mm for this species. In addition to the generally higher robustness of postcranial bones already recorded by previous authors, H. morpheus, similar to Canariomys tamarani, another extinct island species, displayed elongated zygopodium bones of the limbs and a wider distal humerus and femur than in an extant related taxon, Eliomys quercinus. Indexes indicated that Hypnomys was more terrestrial and had greater fossorial abilities than E. quercinus. This was also corroborated by a Discriminant Analysis, although no clear additional inference of locomotory abilities could be calculated

Lines of Descent: Kuhn and Beyond

yesThomas S. Kuhn is famous both for his work on the Copernican Revolution and his ‘paradigm’ view of scientific revolutions. But Kuhn later abandoned the notion of paradigm (and related notions) in favour of a more ‘evolutionary’ view of the history of science. Kuhn’s position therefore moved closer to ‘continuity’ models of scientific progress, for instance ‘chain-of-reasoning’ models, originally championed by D. Shapere. The purpose of this paper is to contribute to the debate around Kuhn’s new ‘developmental’ view and to evaluate these competing models with reference to some major innovations in the history of cosmology, from Copernicanism to modern cosmology. This evaluation is made possible through some unexpected overlap between Kuhn’s earlier discontinuity model and various versions of the later continuity models. It is the thesis of this paper that the ‘chain-of-reasoning’ model accounts better for the cosmological evidence than both Kuhn’s early paradigm model and his later developmental view of the history of science