13,235 research outputs found
Solitonic State in Microscopic Dynamic Failures
Onset of permanent deformation in crystalline materials under a sharp
indenter tip is accompanied by nucleation and propagation of defects. By
measuring the spatio-temporal strain field nearthe indenter tip during
indentation tests, we demonstrate that the dynamic strain history at the moment
of a displacement burst carries characteristics of formation and interaction of
local excitations, or solitons. We show that dynamic propagation of multiple
solitons is followed by a short time interval where the propagating fronts can
accelerate suddenly. As a result of such abrupt local accelerations, duration
of the fast-slip phase of a failure event is shortened. Our results show that
formation and annihilation of solitons mediate the microscopic fast weakening
phase, during which extreme acceleration and collision of solitons lead to
non-Newtonian behavior and Lorentz contraction, i.e., shortening of solitons
characteristic length. The results open new horizons for understanding dynamic
material response during failure and, more generally, complexity of earthquake
sources
Antimicrobial therapy for otitis media with effusion ( secretory otitis media)
Objective. —To determine the effectiveness of antimicrobial treatment for otitis media with effusion ( secretory otitis media) in children.
Data Source. —We report the reexamination of a previously published study by Mandel et al that evaluated the efficacy of a 2-week course of antimicrobials (amoxicillin trihydrate) with and without a 4-week course of an oral decongestant-antihistamine combination in a double-blind, placebo-controlled, randomized trial involving 518 infants and children with otitis media with effusion.
Data Synthesis. —At 4 weeks, amoxicillin efficacy as determined by a tympanometric criterion (P=.121) or by a measure of improvement in hearing (P=.311) was insignificant. Only by otoscopic judgment, which is shown to contain a systematic bias as used in this clinical trial, could an argument be made for a marginal efficacy of amoxicillin at the 4-week end point. Logistic regression analyses of the combined effects of treatment and prognostic factors showed no significant differences between placebo- and antibiotic-treated groups for unilateral effusions and for bilateral effusions. When subjects with unilateral and bilateral effusions were combined, the estimated efficacy of antibiotic treatment was 12.3% by otoscopy (P =.014) and 4.8% by tympanometry (P =.171). We also demonstrate the sensitivity of outcome to diagnostic measures used and provide statistical evidence questioning the validity of otoscopic observations in this study. Six weeks after the termination of amoxicillin therapy, the recurrence of effusion was two to six times higher in the amoxicillin-treated children than in those treated with placebo (P=.001), and resolution of effusion was not significantly different among antibiotic and placebo groups (13.6% and 11.3%, respectively; P=.477).
Conclusions. —Amoxicillin with and without decongestant-antihistamine combination is not effective for the treatment of persistent asymptomatic middle-ear effusions in infants and children
Contrasting the capabilities of building energy performance simulation programs
For the past 50 years, a wide variety of building energy simulation programs have been developed, enhanced and are in use throughout the building energy community. This paper is an overview of a report, which provides up-to-date comparison of the features and capabilities of twenty major building energy simulation programs. The comparison is based on information provided by the program developers in the following categories: general modeling features; zone loads; building envelope and daylighting and solar; infiltration, ventilation and multizone airflow; renewable energy systems; electrical systems and equipment; HVAC systems; HVAC equipment; environmental emissions; economic evaluation; climate data availability, results reporting; validation; and user interface, links to other programs, and availability
The Birth of a Nation – The most stupendous and fascinating motion picture drama created in the United States by D. W. Griffith
https://digitalcommons.gardner-webb.edu/birth-of-nation-program/1000/thumbnail.jp
Off-fault tensile cracks: A link between geological fault observations, lab experiments, and dynamic rupture models
We examine the local nature of the dynamic stress field in the vicinity of the tip of a semi-infinite sub-Rayleigh (slower than the Rayleigh wave speed, c_R) mode II crack with a velocity-weakening cohesive zone. We constrain the model using results from dynamic photoelastic experiments, in which shear ruptures were nucleated spontaneously in Homalite-100 plates along a bonded, precut, and inclined interface subject to a far-field uniaxial prestress. During the experiments, tensile cracks grew periodically along one side of the shear rupture interface at a roughly constant angle relative to the shear rupture interface. The occurrence and inclination of the tensile cracks are explained by our analytical model. With slight modifications, the model can be scaled to natural faults, providing diagnostic criteria for interpreting velocity, directivity, and static prestress state associated with past earthquakes on exhumed faults. Indirectly, this method also allows one to constrain the velocity-weakening nature of natural ruptures, providing an important link between field geology, laboratory experiments, and seismology
Countering the Criminalization of Youth: A Denominational Strategy for Developing a Holistic Ecclesiastical Approach
The purpose of this project is to create a strategy within the North Georgia United Methodist Church Conference (NGUMC) structures to counter the criminalization of youth by engaging in opportunities that bring awareness to the NGUMC and then engage in mentoring and other activities designed to counter this criminalization of youth through holistic and intergenerational approaches at the various ecclesiastical levels within the Conference. There is a growing concern among educators and other youth service professionals in regards to what has been called “the school to prison pipeline.” While a growing number of youth are at risk of falling victim to a culture of criminalization, youth of color and lower socioeconomic status and those in foster care are at particular risk. Few churches are aware that various social agencies are engaging in processes of systemic and systematic criminalization of youth.
This paper is divided into three parts. Part One explores factors contributing to the criminalization of youth in order to gain an understanding of the development and progression of this phenomenon. This portion also examines how criminalization impacts youth, families, and society. Part Two offers an overview of theology found in the Bible and the United Methodist Book of Discipline, each mandating that the Church come to the aid of those most vulnerable.
Part Three suggests how the Church can be a vital part of curtailing the criminalization of young people, especially foster children who are at a greater risk of criminalization. To fulfill the goal of addressing and curtailing this, a collaborative effort with other churches and child/youth service agencies within the community is developed in order to strengthen, equip, educate, and encourage foster and adoptive families. Support also comes in the form of a monthly support group providing training and fellowship. Part Three concludes with an evaluation
Oral History Interview: W.S. Dick Griffith
This interview is one of a series conducted concerning West Virginia communities, focusing on Ceredo. Mr. Dick Griffith was a business man and supporter of Ceredo- Kenova athletics. He discusses: Coach Carl Ward and Coach Craycraft; individuals such as Floyd Stark (president of the Ceredo Bank); as well as the community of Ceredo and their support of athletics.https://mds.marshall.edu/oral_history/1304/thumbnail.jp
Ike\u27s Letters to a Friend, 1941-1958
“Swede Hazlett was one of the people to whom I ‘opened up.’”—Dwight D. Eisenhower Dwight D. Eisenhower and E. E. (“Swede”) Hazlett grew up together in Abilene, Kansas, and remained close, corresponding regularly from 1941 until Hazlett’s death in 1958. The letters collected in this volume, many of them surprisingly revealing, contain Eisenhower’s views on a wide range of diplomatic, military, and political issues. Taken together they constitute a remarkable inner history of Eisenhowers public career. Robert Griffith’s introductory essay is a masterful account of the Eisenhower-Hazlett relationship and of the insights provided by their correspondence for understanding the Eisenhower years. Griffith’s substantial headnotes give additional detail and context where necessary and provide a sense of narrative continuity to the correspondence. The Eisenhower who emerges from these pages bears little resemblance to the bumbling caricature produced by journalists in the 1950s. But neither does he fit the role assigned to him by so many people today, whether liberal critics of the Cold War, conservative opponents of Democratic fiscal policy, or White House aides attempting to “Eisenhowerize” Ronald Reagan. He is, rather, a complex and multidimensional historical figure whom we must study, on his own terms, if we are to fully understand our recent past. Description Robert W. Griffith (1940–2011) was professor of history at American University. He is the author of The Politics ofFear: JosephR. McCarthy and the Senate, as well as more than two dozen articles on the Truman and Eisenhower eras. With a New Foreword by Miroslava Chávez-Garca. This Kansas Open Books title is funded by a grant from the National Endowment for the Humanities and the Andrew W. Mellon Foundation Humanities Open Book Program.https://digitalcommons.pittstate.edu/kansas_open_books/1026/thumbnail.jp
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