587 research outputs found
The long-period binary central stars of the planetary nebulae NGC 1514 and LoTr 5
The importance of long-period binaries on the formation and evolution of
planetary nebulae is still rather poorly understood, in part due to the lack of
central star systems known to comprise such long-period binaries.
Here, we report on the latest results from the on-going Mercator-HERMES
survey for variability in the central stars of planetary nebulae.
We present a study of the central stars of NGC 1514, BD+30623, the
spectrum of which shows features associated with a hot nebular progenitor as
well as a possible A-type companion. Cross-correlation of high-resolution
HERMES spectra against synthetic spectra shows the system to be a highly
eccentric (), double-lined binary with a period of 3300 days.
Previous studies indicated that the cool component might be a Horizontal Branch
star of mass 0.55 M but the observed radial velocity amplitudes
rule out such a low mass. Assuming the nebular symmetry axis and binary orbital
plane are perpendicular, the data are more consistent with a post-main-sequence
star ascending towards the Giant Branch.
We also present the continued monitoring of the central star of LoTr 5, HD
112313, which has now completed one full cycle, allowing the orbital period
(P2700 days) and eccentricity () to be derived.
To date, the orbital periods of BD+30623 and HD 112313 are the
longest to have been measured spectroscopically in the central stars of
planetary nebulae. Furthermore, these systems, along with BD+332642,
comprise the only spectroscopic wide-binary central stars currently known.Comment: 4 pages, 4 figures, 2 tables. Accepted for publication in Astronomy
and Astrophysics Letter
Sensory-Based Interventions in Schools
Dr. Jamie Palmer, DrOT/L of Central Kitsap school district requested that University of Puget Sound occupational therapy (OT) students research the impact of sensory-based interventions (SBIs) on attention, behavior, and academic performance for children in preschool to high school with or without diagnoses. Based on a systematic review of 33 studies, the evidence for the use of SBIs in the classroom to improve academic performance, behavior and attention is preliminary and ranges from limited to moderate depending on the specific type of SBI. The use of those specific SBIs with limited to moderate evidence is recommended for students whose demographic profiles match those of the study participants.
The knowledge translation process consisted of two primary components: developing and delivering an in-service to share findings of the present study with Dr. Palmer and other professionals in her school district, and developing and disseminating an evidence-based movement program called Break 5. School district professionals reported being highly satisfied with the in-service and reported that the program was moderately effective for regulating student behaviors. The principal and occupational therapy team expressed interest in expanding the movement program throughout the school. Given that Break 5 has only been trialed on an informal basis, research is needed to determine its efficacy. Break 5 and those SBIs with the strongest evidence should only be implemented by OTs with strong rationale, systematic outcome monitoring, and adjustment to meet individual needs
Allometry of the Thoracolumbar Region in Running Mammals
Mammals use flexion and extension of the back to increase their stride length and assist with breathing during running. The degree to which vertebral column bending increases stride length varies between dorsomobile (e.g., cheetah) and dorsostable (e.g., horse) taxa. It has been suggested that stability of the thoracolumbar region may correlate with body size because dorsomobile gaits are energetically expensive at large size. This dissertation investigates allometry of the thoracolumbar region and asks: How is vertebral structure influenced by increasing body size, and does this vary among families with different running styles? It presents new data on the influence of size and locomotion on the axial skeleton, an understudied anatomical region.
To address these questions, three families of running mammals with a large size range were sampled: Felidae (cats, dorsomobile), Bovidae and Equidae (bovids and horses, dorsostable). Vertebral material was examined from 57 species (n=216) of felids and bovids, and five extant species and eight fossil genera (n=77) of equids. Vertebral data (linear measures, 2D and 3D landmarks) were compared to body size estimated from limb dimensions.
Scaling of the ventral column (centra and discs) is consistent with its perceived role in body support as a dorsal compressive element, becoming craniocaudally shorter and dorsoventrally deeper with increasing body size. Morphological features of the lumbar region associated with stability are also correlated with size, but size explains a greater proportion of shape variation in bovids than felids. This suggests passive stabilization of the lumbar region in dorsostable groups may be a size-dependent response to cursoriality.
Preliminary data suggest that the shape of the intervertebral joint complex reflects its range of motion, highlighting the utility of joint shape for understanding axial function. Specifically, craniocaudal patterns of lumbar morphology reflect differences in craniocaudal mobility between dorsomobile and dorsostable runners, which isolate mobility to the lumbosacral joint. Based on joint shape, small-bodied fossil equids (e.g., Hyracotherium) likely had more flexibility of the anterior lumbar region than modern horses, and therefore may have used more diverse gaits. However, specialization of the lumbosacral joint evolved early in equids, predating unguligrady and extreme digit loss
Using apps to capture personally meaningful data on lived experience from patients with long term conditions
Getting it right: creating partnerships for change. Integrating Aboriginal and Torres Strait Islander knowledges in social work education and practice
The 2012 Australian Social Work Education and Accreditation Standards (ASWEAS) state that Aboriginal and Torres Strait Islander ways of knowing, being and doing are one of four essential core curriculum content areas alongside Mental Health, Child Wellbeing and Protection and Cross-cultural knowledge and skills, that must now be included in all Australian Association of Social Workers (AASW)-accredited social work programs (Australian Association of Social Workers, 2012a). By articulating this new requirement, the AASW is asserting that social workers need to be informed by Aboriginal and Torres Strait Islander knowledges in all areas of practice
Ontogenetic changes in shape and growth rate during postnatal development in false killer whales (<i>Pseudorca crassidens</i>) vertebral column
Intraspecific variation in cetacean vertebral anatomy as a result of ageing, growth, and sexual dimorphism is poorly understood. Using 3D geometric morphometrics, we investigated allometric patterns, sexual dimorphism, and ontogenetic trajectories in the vertebral column of false killer whale (Pseudorca crassidens). Our data set includes thoracic, lumbar, and caudal vertebrae of 30 specimens, including neonates, juveniles, and adults of both sexes. Vertebral shape was significantly correlated with size within each region. Neonatal vertebral shape differed significantly from juveniles and adults, displaying ontogenetic shape change. Allometric and growth patterns of the vertebral regions, particularly of the lumbar region with the thoracic and caudal regions, differed significantly, which may influence the function and mobility patterns of the vertebral regions during different life stages. Using quantitative methods, we could not conclude that the Pseudorca vertebrae are sexually dimorphic. This study describes for the first time intraspecific vertebral patterns in a cetacean species across ontogenetic stages. Pseudorca individuals live in large pods and swim together, sharing the same swimming mode. The neonates have a more flexible column and swim less efficiently following their mothers to nurse
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