172 research outputs found
Settling and Laying Down: A Cultural History of Quakers in Savannah and Statesboro, Georgia
This descriptive cultural history follows a hybrid methodology often applied to ethno-histories. This approach combines archival research, oral history, and ethnography, with reflexive aspects. I explore some similarities and differences between two Quaker meetings in Southeast Georgia, the small but growing urban meeting in Savannah and a discontinued rural one in the small college town of Statesboro (that sometimes met in the village of Guyton). These case studies of local and personal histories, combined with my observations as a participant in the life of the community, are designed to illuminate fine details of Quaker culture in the recent Deep South
Detection of pediatric upper extremity motor activity and deficits with accelerometry
Importance: Affordable, quantitative methods to screen children for developmental delays are needed. Motor milestones can be an indicator of developmental delay and may be used to track developmental progress. Accelerometry offers a way to gather real-world information about pediatric motor behavior.
Objective: To develop a referent cohort of pediatric accelerometry from bilateral upper extremities (UEs) and determine whether movement can accurately distinguish those with and without motor deficits.
Design, Setting, and Participants: Children aged 0 to 17 years participated in a prospective cohort from December 8, 2014, to December 29, 2017. Children were recruited from Ranken Jordan Pediatric Bridge Hospital, Maryland Heights, Missouri, and Washington University School of Medicine in St Louis, St Louis, Missouri. Typically developing children were included as a referent cohort if they had no history of motor or neurological deficit; consecutive sampling and matching ensured equal representation of sex and age. Children with diagnosed asymmetric motor deficits were included in the motor impaired cohort.
Exposures: Bilateral UE motor activity was measured using wrist-worn accelerometers for a total of 100 hours in 25-hour increments.
Main Outcomes and Measures: To characterize bilateral UE motor activity in a referent cohort for the purpose of detecting irregularities in the future, total activity and the use ratio between UEs were used to describe typically developing children. Asymmetric impairment was classified using the mono-arm use index (MAUI) and bilateral-arm use index (BAUI) to quantify the acceleration of unilateral movements.
Results: A total of 216 children enrolled, and 185 children were included in analysis. Of these, 156 were typically developing, with mean (SD) age 9.1 (5.1) years and 81 boys (52.0%). There were 29 children in the motor impaired cohort, with mean (SD) age 7.4 (4.4) years and 16 boys (55.2%). The combined MAUI and BAUI (mean [SD], 0.86 [0.005] and use ratio (mean [SD], 0.90 [0.008]) had similar F1 values. The area under the curve was also similar between the combined MAUI and BAUI (mean [SD], 0.98 [0.004]) and the use ratio (mean [SD], 0.98 [0.004]).
Conclusions and Relevance: Bilateral UE movement as measured with accelerometry may provide a meaningful metric of real-world motor behavior across childhood. Screening in early childhood remains a challenge; MAUI may provide an effective method for clinicians to measure and visualize real-world motor behavior in children at risk for asymmetrical deficits
Modeling metallic island coalescence stress via adhesive contact between surfaces
Tensile stress generation associated with island coalescence is almost
universally observed in thin films that grow via the Volmer-Weber mode. The
commonly accepted mechanism for the origin of this tensile stress is a process
driven by the reduction in surface energy at the expense of the strain energy
associated with the deformation of coalescing islands during grain boundary
formation. In the present work, we have performed molecular statics
calculations using an embedded atom interatomic potential to obtain a
functional form of the interfacial energy vs distance between two closely
spaced free surfaces. The sum of interfacial energy plus strain energy provides
a measure of the total system energy as a function of island separation.
Depending on the initial separation between islands, we find that in cases
where coalescence is thermodynamically favored, gap closure can occur either
spontaneously or be kinetically limited due to an energetic barrier. Atomistic
simulations of island coalescence using conjugate gradient energy minimization
calculations agree well with the predicted stress as a function of island size
from our model of spontaneous coalescence. Molecular dynamics simulations of
island coalescence demonstrate that only modest barriers to coalescence can be
overcome at room temperature. A comparison with thermally activated coalescence
results at room temperature reveals that existing coalescence models
significantly overestimate the magnitude of the stress resulting from island
coalescence.Comment: 20 pages, 8 figures, 2 tables, submitted to PR
CWRML: representing crop wild relative conservation and use data in XML
Background
Crop wild relatives are wild species that are closely related to crops. They are valuable as potential gene donors for crop improvement and may help to ensure food security for the future. However, they are becoming increasingly threatened in the wild and are inadequately conserved, both in situ and ex situ. Information about the conservation status and utilisation potential of crop wild relatives is diverse and dispersed, and no single agreed standard exists for representing such information; yet, this information is vital to ensure these species are effectively conserved and utilised. The European Community-funded project, European Crop Wild Relative Diversity Assessment and Conservation Forum, determined the minimum information requirements for the conservation and utilisation of crop wild relatives and created the Crop Wild Relative Information System, incorporating an eXtensible Markup Language (XML) schema to aid data sharing and exchange.
Results
Crop Wild Relative Markup Language (CWRML) was developed to represent the data necessary for crop wild relative conservation and ensure that they can be effectively utilised for crop improvement. The schema partitions data into taxon-, site-, and population-specific elements, to allow for integration with other more general conservation biology schemata which may emerge as accepted standards in the future. These elements are composed of sub-elements, which are structured in order to facilitate the use of the schema in a variety of crop wild relative conservation and use contexts. Pre-existing standards for data representation in conservation biology were reviewed and incorporated into the schema as restrictions on element data contents, where appropriate.
Conclusion
CWRML provides a flexible data communication format for representing in situ and ex situ conservation status of individual taxa as well as their utilisation potential. The development of the schema highlights a number of instances where additional standards-development may be valuable, particularly with regard to the representation of population-specific data and utilisation potential. As crop wild relatives are intrinsically no different to other wild plant species there is potential for the inclusion of CWRML data elements in the emerging standards for representation of biodiversity data
Exile Vol. IX No. 2
FICTION
Robert & Muriel or, If You Think of the Girl You Love Too Much As Someday Being Bald, You Can Always Remain Aloof by Johnathan Reynolds 7-14
Quentin Marsh by Margaret Polishook 15
Used To Be by Susan Smith 17-23
It Was a Chatham Day by Caroline Baird 33-37
Where All the Artists Go by George Estes 41-43
September by Cynthia Winzeler 45-50
ESSAY
Carthartes Aura by Richard Boyer 27-29
POETRY
To A Mouse by Kay Stein 24-25
Poem by Christine Cooper 26
For Sylvia Plath by Robert Hoyt 26
On Studying Shakespeare by Christine Cooper 29
Song by Judith Pyster 30-31
Prestidigitation by Michael Glaser 37
Poem by Sarah Conway 39
Poem by Barbara Thiele 50
An Old Man\u27s Lament by Robert Hoyt 51
GRAPHICS
Pastel by Lynne Wiley 4
Pen Drawing by Elizabeth Surbeck 6
Pen Sketch by Martha Merselis 14
Pen and Ink by Matha Merselis 16
Brush Drawing by Martha Merselis 24
Pen Sketches by Martha Merselis 30
Pencil Drawing by Patterson Bouic 32
Pen and Ink by Katheryn Knapp 38
Brush Drawing by Sara Henry 40
Pen and Ink by Martha Merselis 4
Evidence for a Mass Dependent Step-Change in the Scaling of Efficiency in Terrestrial Locomotion
A reanalysis of existing data suggests that the established tenet of increasing efficiency of transport with body size in terrestrial locomotion requires re-evaluation. Here, the statistical model that described the data best indicated a dichotomy between the data for small (<1 kg) and large animals (>1 kg). Within and between these two size groups there was no detectable difference in the scaling exponents (slopes) relating metabolic (Emet) and mechanical costs (Emech, CM) of locomotion to body mass (Mb). Therefore, no scaling of efficiency (Emech, CM/Emet) with Mb was evident within each size group. Small animals, however, appeared to be generally less efficient than larger animals (7% and 26% respectively). Consequently, it is possible that the relationship between efficiency and Mb is not continuous, but, rather, involves a step-change. This step-change in the efficiency of locomotion mirrors previous findings suggesting a postural cause for an apparent size dichotomy in the relationship between Emet and Mb. Currently data for Emech, CM is lacking, but the relationship between efficiency in terrestrial locomotion and Mb is likely to be determined by posture and kinematics rather than body size alone. Hence, scaling of efficiency is likely to be more complex than a simple linear relationship across body sizes. A homogenous study of the mechanical cost of terrestrial locomotion across a broad range of species, body sizes, and importantly locomotor postures is a priority for future research
Recommended from our members
A robust, coupled approach for atomistic-continuum simulation.
This report is a collection of documents written by the group members of the Engineering Sciences Research Foundation (ESRF), Laboratory Directed Research and Development (LDRD) project titled 'A Robust, Coupled Approach to Atomistic-Continuum Simulation'. Presented in this document is the development of a formulation for performing quasistatic, coupled, atomistic-continuum simulation that includes cross terms in the equilibrium equations that arise due to kinematic coupling and corrections used for the calculation of system potential energy to account for continuum elements that overlap regions containing atomic bonds, evaluations of thermo-mechanical continuum quantities calculated within atomistic simulations including measures of stress, temperature and heat flux, calculation used to determine the appropriate spatial and time averaging necessary to enable these atomistically-defined expressions to have the same physical meaning as their continuum counterparts, and a formulation to quantify a continuum 'temperature field', the first step towards constructing a coupled atomistic-continuum approach capable of finite temperature and dynamic analyses
- …