241 research outputs found
Influence of a humidor on the aerodynamics of baseballs
We investigate whether storing baseballs in a controlled humidity environment
significantly affects their aerodynamic properties. To do this, we measure the
change in diameter and mass of baseballs as a function of relative humidity
(RH) in which the balls are stored. We then model trajectories for pitched and
batted baseballs to assess the difference between those stored at 30% RH versus
50% RH. The results show that a drier baseball may be expected to curve
slightly more than a humidified one for a given pitch velocity. We also find
that the aerodynamics alone would add ~2 feet to the distance a moister ball is
hit. However, this is compensated by a ~6 foot reduction in batted distance due
to the well known change in coefficient of restitution of the ball. We discuss
consequences of these results for baseball played at Coors Field in Denver,
where baseballs have been stored in a humidor at 50% RH since 2002.Comment: 21 pages, 7 figures, modified and re-posted 2/2
Genetic Mosaic Analysis Indicates That the Bulb Region of Coat Hair Follicles Contains a Resident Population of Several Active Multipotent Epithelial Lineage Progenitors
AbstractThe hair follicle represents an excellent model system for exploring the properties of lineage-forming units in a dynamic epithelium containing multiple cell types. During its growth (anagen) phase, the proximalâdistal axis of the mouse coat hair (pelage) follicle provides a historical record of all epithelial lineages generated from its resident stem cell population. An unresolved question in the field is whether the bulb region of anagen pelage follicles contains multipotential progenitors and whether their individual contribution to cellular census fluctuates over time. To address this issue, chimeric follicles were harvested in midanagen from three types of genetic mosaic mouse models. Analysis of the distribution of genotypic markers, including digital three-dimensional reconstruction of serially sectioned chimeric follicles, revealed that on average the bulb contains four or fewer active progenitors, each capable of giving rise to all six follicular epithelial fates. Moreover, analysis of mosaic pelage, as well as cultured whisker follicles provided evidence that bulb-associated progenitors can give rise to expanding descendant clones during midanagen, leading to the conclusion that the bulb contains dormant or symmetrically dividing stem cells. This latter feature resembles the behavior of hematopoietic stem cells after bone marrow transplantation, and raises the question of whether this property may be shared by stem cells in other self-renewing epithelia
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Looking Back and Looking Forward: Some Reflections on Journal Developments and Trends in Organizational Change Discourse
Implementation of electronic patient-reported outcomes for symptom monitoring in a large multisite community oncology practice: Dancing the texas two-step through a pandemic
PURPOSE Among patients receiving chemotherapy, symptom monitoring with electronic patient-reported outcomes (ePROs) is associated with improved clinical outcomes, satisfaction, and compliance with therapy. Standard approaches for ePRO implementation are not established, warranting evaluation in community cancer practices. We present implementation findings of ePRO symptom monitoring across a large multisite community oncology practice network. METHODS Patients initiating a new systemic therapy at one of the 210 practice sites at Texas Oncology were invited to use the Navigating Cancer ePRO platform, with stepped-wedge implementation from July to December 2020. Participating patients received a weekly prompt by text message or e-mail to self-report common symptoms and well-being. Severe self-reported symptoms triggered a real-time notification to nursing triage to address the symptom. Enrollment and compliance were systematically tracked weekly with evaluation of barriers and facilitators to adoption and sustainability. RESULTS Four thousand three hundred seventy-five patients planning systemic treatment were enrolled and participated. Seventy-three percent (1,841 of 2,522) of enrolled patients completed at least one ePRO assessment. Among these individuals, 64% (16,299 of 25,061) of available weekly ePRO assessments were completed. Over a 10-week period, compliance declined from 72% to 52%. Barriers currently being addressed include lack of a second reminder text or e-mail prompt, inconsistent discussion of reported ePROs by clinicians at visits, and COVID-related changes in workflow. Facilitators included ease of use and patient and staff engagement on the importance of PROs for symptom management. CONCLUSION ePROs can be effectively implemented in community oncology practice. Utilization of ePROs is high but diminishes over time without attention to barriers. Ongoing work to address barriers and optimize compliance are underway
Student politics, teaching politics, black politics: an interview with Ansel Wong
Ansel Wong is the quiet man of British black politics, rarely in the limelight and never seeking political office. And yet his âcareerâ here â from Black Power firebrand to managing a multimillion budget as head of the Greater London Councilâs Ethnic Minority Unit in the 1980s â spells out some of the most important developments in black educational and cultural projects. In this interview, he discusses his identification with Pan-Africanism, his involvement in student politics, his role in the establishment of youth projects and supplementary schools in the late 1960s and 1970s, and his involvement in black radical politics in London in the same period, all of which took place against the background of revolutionary ferment in the Third World and the world of ideas, and were not without their own internal class and ethnic conflicts
A taxonomic backbone for the global synthesis of species diversity in the angiosperm order Caryophyllales
The Caryophyllales constitute a major lineage of flowering plants with approximately 12500 species in 39 families. A taxonomic backbone at the genus level is provided that reflects the current state of knowledge and accepts 749 genera for the order. A detailed review of the literature of the past two decades shows that enormous progress has been made in understanding overall phylogenetic relationships in Caryophyllales. The process of re-circumscribing families in order to be monophyletic appears to be largely complete and has led to the recognition of eight new families (Anacampserotaceae, Kewaceae, Limeaceae, Lophiocarpaceae, Macarthuriaceae, Microteaceae, Montiaceae and Talinaceae), while the phylogenetic evaluation of generic concepts is still well underway. As a result of this, the number of genera has increased by more than ten percent in comparison to the last complete treatments in the Families and genera of vascular plantsâ series. A checklist with all currently accepted genus names in Caryophyllales, as well as nomenclatural references, type names and synonymy is presented. Notes indicate how extensively the respective genera have been studied in a phylogenetic context. The most diverse families at the generic level are Cactaceae and Aizoaceae, but 28 families comprise only one to six genera. This synopsis represents a first step towards the aim of creating a global synthesis of the species diversity in the angiosperm order Caryophyllales integrating the work of numerous specialists around the world
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Neuromodulatory Control of Brainstem Function in Health and Disease
View full text in DOAB: Directory of Open Access Book
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Neuromodulatory Control of Spinal Function in Health and Disease
View full text in DOAB: Directory of Open Access Book
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