7,835 research outputs found
Phonon Thermodynamics versus Electron-Phonon Models
Applying the path integral formalism we study the equilibrium thermodynamics
of the phonon field both in the Holstein and in the Su-Schrieffer-Heeger
models. The anharmonic cumulant series, dependent on the peculiar source
currents of the {\it e-ph} models, have been computed versus temperature in the
case of a low energy oscillator. The cutoff in the series expansion has been
determined, in the low limit, using the constraint of the third law of
thermodynamics. In the Holstein model, the free energy derivatives do not show
any contribution ascribable to {\it e-ph} anharmonic effect. We find signatures
of large {\it e-ph} anharmonicities in the Su-Schrieffer-Heeger model mainly
visible in the temperature dependent peak displayed by the phonon heat
capacity
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Subjects or objects? prisoners and human experimentation
During the 1950s, inmates at what was then called Holmesburg Prison, in Philadelphia, were inoculated with condyloma acuminatum, cutaneous moniliasis, and viruses causing warts, herpes simplex, and herpes zoster. For participating in this research, and in studies exposing them to dioxin and agents of chemical warfare, they were paid up to $1,500 a month. Between 1963 and 1971, researchers in Oregon and Washington irradiated and repeatedly took biopsy specimens from the testicles of healthy prisoners; the men subsequently reported rashes, peeling, and blisters on the scrotum as well as sexual difficulties. Hundreds of such experiments induced the federal government to essentially ban research involving prisoners in 1978. The message: such research is fundamentally exploitative and thus unethical. Yet a recent report by the Institute of Medicine (IOM) has opened the closed door, arguing not only that such research can be performed appropriately but that prisoners deserve to be included in investigative studies — at least those who might benefit directly. Examination of the explanations behind U.S. restrictions on prison research and their current applicability can provide guidance for today's policy debates
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Last-ditch medical therapy : revisiting lobotomy
Desperate times call for desperate measures. So thought Walter J. Freeman, a neurologist who became the United States's staunchest advocate of the lobotomy between the 1930s and the 1970s. A new book, The Lobotomist, by journalist Jack El-Hai,1 chronicles Freeman's advocacy of a procedure that was viewed by many, and continues to be viewed, as barbaric. In exploring the ways in which lobotomy became part of common medical practice, El-Hai raises questions not only about how we should judge the procedure in retrospect, but also about what lobotomy teaches us about last-ditch medical interventions
The Government of London and its relations with the Crown 1400 - 1450
PhDThe available sources have, to some extent, determined the form of
this thesis, which was undertaken in the hope that a more detailed study of
the relations between London and the Crown during the years 1400-1150 would
place in perspective the crises with which it begins and ends. The most
important source of material for this study has been the Journals of the
Court of Aldermen and Common Council which survive from 1416 (the years 1429-
1436 are missing). Historians with the help of a nineteenth century index
have quarried in these Journals, but they have never been read through
systematically. Journals nos. 3 and 6, having been wrongly bound up, could
not be used until their pages had been sorted into the correct order from
the internal evidence of their contents. The scribes who compiled the
Journals were both careless and cautious which increases the difficulty in
interpreting their crabbed notes. From studying the Journals dominant themes
emerged which were then followed up at the Public Record Office and elsewhere.
The conclusions from this study fall into three main categories. The
Journals provided a great deal of material from which it was possible to
draw a much more detailed picture of the machinery and business of the
government of medieval London. The Aldermen and civic officials emerge as
conservative, but conscientious, men who might press hardly upon minority
interests, but had constantly before their eyes the needs of the City as a
whole.
Secondly it has been possible to tidy up the chronology of the crises
themselves. At such times as Bolingbroke's usurpation and Cade's revolt the civic scribes were least active and most cautious. But it seems clear that
the London support for both these men has been exaggerated and that the
fundamental conservatism of the City governors was not easily rocked, whether
by royal scions or Kentish peasants.
But this study has proved most useful where the more mundane contact
between the Crown and the citizens could be examined, In this way it has
been possible to place the financial relations between the King and the City
in perspective, and to realize that the King did not come as a beggar to the
Londoners, since he had at his disposal all the chartered freedoms and
privileges which were essential to the communal and economic life of the
City. London, in spite of its great prestige and financial importance, still
operated in the fifteenth century within a framework of royal privilege.
'While the memory of Richard II's action in 1392 was still, green, the
Londoners were in no position to demand redress of grievances before supply.
In understanding the delicate balance of the relationship between the Crown
and the Londoners it is easier to understand the survival of the Lancastrian
dynasty
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Remembering Berton Roueché: Master of Medical Mysteries
Berton Roueché wrote the “Annals of Medicine” feature in the New Yorker magazine from the 1940s until the 1980s. Roueché developed his innovative approach to medical writing at a time when two important transformations were occurring in American medicine: the emergence of clinical epidemiology and the growth of media coverage of medical topics. Roueché was an immensely talented writer and storyteller, and his writings introduced not only laypersons but also future generations of physicians to the art of medicine
Student progress monitoring: teachers\u27 perceptions
The Mississippi Student Progress Monitoring System (MSPMS) was developed for the Mississippi Department of Education to be used to monitor student progress on the state framework which constitutes the curriculum for each course taught in Mississippi schools. This study was designed to investigate teachers’ perceptions of the implementation and use of the MSPMS. Research question 1 was to determine if the various independent variables of age, level of education, years of experience as an educator, level of school where teaching, perceived level of computer and/or technology comfort, perceived level of computer and/or technology experience, subject area taught, number of MSPMS tests created, number of MSPMS tests given, amount of support provided, whether program works, and importance of information gained from MSPMS made any difference in teachers’ perceptions of the implementation and use of the MSPMS; and research question 2 was to determine whether the teachers’ perceptions and the various independent variables had any significant relationships. Research question 3 looked at teachers’ attitudes toward MSPMS. There were no statistically significant differences among the dependent and independent variables. Findings for research question 2 showed that there were no statistically significant correlations among the dependent and independent variables. However, correlations among the independent variables revealed statistically significant relationships between age and years of experience, subjects taught and school level taught, technology experience and level of education, and subjects taught and number of tests given. Examination of the response frequencies for situations in the vignettes for research question 3 revealed that teachers reported feeling more frustrated than anything else when confronted with adversities with the technologies or the MSPMS. All of the findings in this study are limited to a rural Mississippi school district using MSPMS
Establishing Criteria for the Pre-Service Selection of Teachers with Special Application to the Utah State Agricultural College
Our American culture and civilization depends in large measure upon the recruiting of the right kind of men and women to be teachers in our American schools and colleges. All professions depend on effective teaching for their life blood. Many educators and colleges during the past few years have become concerned with pre-service selection methods for improving the teaching personnel. This concern has become somewhat intensified at the present time, largely as a result of four factors. One factor is the large number of returning servicemen, who are turning to teaching as a career. A second factor is improved salaries and tenure laws. A third factor, suggested by Dr. Ray C. Maul is that many people are turning to teaching only because schools continue to operate though good times and bad. A fourth factor common to many prospective teachers is that the idealism connected with teaching attracts them into the profession. The objective of this study is to obtain evidence from a reveiw of literature, opinions of educators and the preservice selection practices used in other colleges to establish criteria that are considered to be the most desirable factors and techniques used in the pre-service selection of teachers as found by an investigation of the literature. The criteria will be used as a basis for making an analysis of the available records of the students and practices used in the guidance program in the School of Education at Utah State Agricultural College. In this manner the limitations or success of the guidance program as indicated will be somewhat more meaningful
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