2,037 research outputs found
External interventions and the duration of civil wars
Get PDFThe authors combine an empirical model of external intervention, with a theoretical model of civil war duration. Their empirical model of intervention allows them to analyze civil war duration, using"expected"rather than"actual"external intervention as an explanatory variable in the duration model. Unlike previous studies, they find that external intervention is positively associated with the duration of civil war. They distinguish partial third-party interventions that extend the length of war, from multilateral"peace"operations, which have a mandate to restore peace without taking sides - and which typically take place at war's end, or at least when both sides have agreed to a cease-fire. In a future paper, the authors will examine whether partial third-party interventions - whatever their effect on a war's duration - increase the risk of war's recurrence. If that proves true, then even if interventions reduce the length of civil war, they may do so at the cost of further destabilizing the political system, and sowing the seeds of future rebellion.Children and Youth,Peace&Peacekeeping,Post Conflict Reconstruction,Post Conflict Reconstruction,International Affairs,Post Conflict Reconstruction,Social Conflict and Violence,Peace&Peacekeeping,Post Conflict Reconstruction,International Affairs
Talmudic Quotations in Nicholas of Lyra's Postilla Literalis
Get PDFThe Postilla literalis super totam Bibliam, written by Nicholas of Lyra (France, 1270- 1349) is remarkable for the extensive use of texts and oral traditions of Jewish origin made by its author. This paper deals with the place of the Talmud among the Jewish sources cited in the Postilla. For Nicholas the Talmud was a new doctrine invented by the Jews sometime in their past but believed to be divine and to be given to Moses in Sinai. When reading Nicholas' Postilla, one finds many citations from medieval Jewish sources, but very few excerpts from the Talmud except as polemic with the purpose of ridiculing and disproving them. It appears that Nicholas avoided direct Talmudic citations within the Postilla, likely due to the hostile attitudes prevalent specifically toward the Talmud within the Christian world he inhabited
Author(s): Ezra Brown and Nicholas Loehr Source
No full textJSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. . Why is PSL(2, 7) = GL(3, 2)? Mathematical Association of America Ezra Brown and Nicholas Loehr 1. INTRODUCTION. The groups of invertible matrices over finite fields are among the first groups we meet in a beginning course in modern algebra. Eventually, we find out about simple groups and that the unique simple group of order 168 has two representations as a group of matrices. And this is where we learn that the group of 2x2 unimodular matrices over a seven-element field, with / and -/ identified, is isomorphic to the group of invertible 3x3 matrices over a 2-element field. In short, it is a fact that PSL(2, 7) = GL(3, 2). Many of us are surprised by this fact: why should a group of 2 x 2 matrices with mod-7 integer entries be isomorphic to a group of 3 x 3 binary matrices? There are a number of proofs of this remarkable theorem. Dickson [1, p. 303] gives a proof based on his general theorem giving uniform sets of generators and relations for the family of groups SL(2, q), where q is any prime power. One checks that the relations appearing in Dickson's presentation of PSL(2, 7) are satisfied by certain generators of GL(3, 2), implying that these groups have the same presentations and are therefore isomorphic. Dummit and Foote [2, show that every simple group of order 168 is necessarily isomorphic to the automorphism group Aut(.F) of the Fano plane T. They then show that Aut(^) = GL(3, 2) and that PSL(2, 7) is a simple group of order 168; the isomorphism theorem follows. Rotman gives the result as an exercise [5, Exercise 9.26, p. 281]. A hint is to begin with a simple group G of order 168 and use the seven conjugates of a Sylow 2-subgroup P of G to construct a sevenpoint projective plane; the proof is similar to Dummit and Foote's proof. Jeurissen [4] proves the result by showing that both PSL(2, 7) and GL(3, 2) are subgroups of index 2 of the automorphism group of a Coxeter graph. Elkies The aim of this paper is to give a proof that PSL(2, 7) = GL(3, 2) that is elementary in the sense that it uses neither simplicity, nor projective geometry, nor block designs. We will not prove the fact that any two simple groups of order 168 are isomorphic, nor will we use this fact in our proof. What makes our proof work is that: (a) we can identify GL(3, 2) with the set of invertible F2-linear transformations on the finite field with eight elements; (b) 7 = 23 -1; (c) the nonzero squares mod 7 are precisely the powers of 2 mod 7; (d) squaring mod 2 is additive (the Freshman's Dream); and (e) the mapping k h+ -i/k mod 7 translates to a bit-switch mod 2 -which is linear. We begin by giving functional descriptions for both groups, determining their sizes
Recommended from our members
Nicholas and Anna Ricco Ethics Awards
No full textThis paper was awarded a Nicholas and Anna Ricco Ethics Award for 2013. In this paper, the author discusses the "Triple-P" domains of ethical behavior: (1) the understanding of privacy ethics, (2) regards to piracy and plagiarism, and (3) pilfering and profiteering
Characterization and structure in the development of Tudor comedy
Get PDFThe role of characterization in dramatic structure is assessed by theoretical criteria.
Characters who perform actions necessary for the completion of the narrative sequence are
said to be "bound" to the narrative; those without such obligations are "free". Characters
who maintain a single, constant meaning during the course of a play are said to be "static";
characters who change or develop into new roles are "dynamic". Horatian decorum
demanded that comic characters be static, and the characters of Plautine and Terentian
tradition were almost always bound to narrative intrigue. However, evaluations of six
Tudor comedies show an increasing use of non-classical characterization within the comic
form.
In the early comedies lohan lohan and Roister Doister all characters are bound and
static, yet the impetus to enlarge the role of characterization is evident. The characters of
lohan lohan are expanded from their French source, and Roister Doister includes
extraneous episodes in which Udall displays his braggart hero. Free characters abound in
Misogonus; as well the play brings dynamic characterization into the scope of comedy with
the conversion of its prodigal son.
Free characters offer new possibilities of non-narrative plotting. In comedies of the
1580s favourite traditional characters appear as diversions outside the action, and thematic
arrangements of characters inform the increasingly complex plots. Lyly stresses the
symbolic potential of characters in Endimion, whereas Greene uses dynamic
characterization to heighten the illusion of independent figures in Friar Bacon and Friar
Bungay. Love's Labour's Lost exposes the limitations of comic artifice by pulling the
characters between convention and individualization.
By the end of the sixteenth century free and dynamic characters had become
common, and characterization had established a sizable claim on the design of English
comedy. These developments set the English form apart from its neoclassical counterparts
The Watchman in the Vineyard: Historical Traces of Judicial and Punitive Practices in Lincoln
No full textThe theme and content of this edited book first took shape at an international conference I co-organised at the University of Lincoln in November 2009. Bringing together eminent architects, philosophers, criminologists, judges, lawyers, urban designers and geographers, the conference provided a unique platform for debating some of the key issues about the role of architecture in the deliberations of justice in both a contemporary and historical contexts. The significance of the conference, and subsequent publication of selected papers, was underlined by Baroness Vivien Stern (international authority on criminal justice and author of the Forward to this book) who recognized the uniqueness of the initiative in bringing together for the first time both academics and practitioners with diverse interests in the field of justice. The setting of Lincoln for the conference was not without significance. Famous for its majestic cathedral, the city is also noted for its medieval castle which was used as a prison, containing one of the last remaining chapels used under the so-called ‘Pentonville’ (or isolation) system. A special visit to the castle was organised as part of the two day event. My chapter in this volume draws upon this aspect of Lincoln’s history, by examining the topographical and political relationships between castle and cathedral in Lincoln. It develops from an ongoing research project on Lincoln Cathedral and its symbolic and topographical significance (originally published as a chapter in my book, Disclosing Horizons: Architecture, Perspective and Redemptive Space – Routledge 2007). In this paper, however, I examine the judicial and punitive practices in the ‘upper town’ of the city from the Middle Ages to the early 19th century. The study highlights how these practices were closely allied to jurisdictional claims of both castle (bailey) and cathedral (minster close), that variously defined territorially the implementation of canon and civil law
Applying transportation asset management in Connecticut
No full textTitle from cover.; "Author(s): Nicholas Lownes, PhD, Study Manager; Adam Zofka, PhD, Study Manager"--p. iii.; " ... prepared in cooperation with the U.S. Department of Transportation, Federal Highway Administration"--p. iii.; "December 2008."; Includes bibliographical references (p. 49-52).; Final report;; Performed by the Connecticut Academy of Science and Engineering; sponsored by the Connecticut Dept. of Transportation
The Reformation and the Remnant
No full textIn The Reformation and the Remnant, author Nicholas Miller examines crucial issues and questions facing the Adventist Church today through the lenses provided by the thoughts and ideas of various Protestant reformers. Miller discusses such topics as biblical authority and inspiration, the great controversy theme, religious liberty and public morality, last day events and Sunday laws, and righteousness by faith and perfection, as he reveals why the ideas that shaped the Christian church still matter.https://digitalcommons.andrews.edu/sem-books/1039/thumbnail.jp
Open access self-archiving: An author study
No full textThis, our second author international, cross-disciplinary study on open access had 1296 respondents. Its focus was on self-archiving. Almost half (49%) of the respondent population have self-archived at least one article during the last three years. Use of institutional repositories for this purpose has doubled and usage has increased by almost 60% for subject-based repositories. Self-archiving activity is greatest amongst those who publish the largest number of papers. There is still a substantial proportion of authors unaware of the possibility of providing open access to their work by self-archiving. Of the authors who have not yet self-archived any articles, 71% remain unaware of the option. With 49% of the author population having self-archived in some way, this means that 36% of the total author population (71% of the remaining 51%), has not yet been appraised of this way of providing open access. Authors have frequently expressed reluctance to self-archive because of the perceived time required and possible technical difficulties in carrying out this activity, yet findings here show that only 20% of authors found some degree of difficulty with the first act of depositing an article in a repository, and that this dropped to 9% for subsequent deposits. Another author worry is about infringing agreed copyright agreements with publishers, yet only 10% of authors currently know of the SHERPA/RoMEO list of publisher permissions policies with respect to self-archiving, where clear guidance as to what a publisher permits is provided. Where it is not known if permission is required, however, authors are not seeking it and are self-archiving without it. Communicating their results to peers remains the primary reason for scholars publishing their work; in other words,
researchers publish to have an impact on their field. The vast majority of authors (81%) would willingly comply with a mandate from their employer or research funder to deposit copies of their articles in an institutional or subject-based repository. A further 13% would comply reluctantly; 5% would not comply with such a mandate
Characterization of 5-Hydroxytryptamine-Evoked Isometric Contractile Responses in Aortic Vascular Smooth Muscle in Thyropathological Rats
Get PDFviii, 48 leaves. Advisor: Donald B. StrattonThe problem, in the past, research on these sequellae of thyropathology has utilized a variety of animal models. Recently, vascular smooth muscle has increasingly been used as an effective bioassay to assess physiological function of
hormones and ligands. While general effects of thyroid status are well documented, specific thyropathologic-induced changes in 5-hydroxytryptamine (serotonergic; 5-HT) receptor function mediating contraction/dilation in rat aorta have not been completely characterized.
Procedure. Aortic rings from hyperthyroid (TRX),hypothyroid (PTU), and euthyroid control (CON) rats were mounted in climate controlled tissue baths and subjected to isometric contraction experiments. The endothelium was removed from some rings (denuded) while others were left intact. All rings were initially contracted with a single dose of 55 mM KCl and then relaxed to normal potassium while
concomitantly measuring the time course of this relaxation. All rings were subsequently subjected to dose/response experiments with 5-HT, either in the presence or absence of ketanserin (5-HT2 antagonist) and ICS 205-930(5-UT3 antagonist).
Flndings. 5-HT generated a nonsignificant trend toward increased contractile tension in TRX rats, but a significant reduction in contractile tension in rings from PTU rats. These differences were eliminated in the denuded preparations with PTU and control tensions increasing back to TRX levels. There were no differences in sensitivity to 5-HT in the intact preparations in the three thyroid groups, but an increased sensitivity was observed in the TRX denuded preparation. Ketanserin was found to completely antagonize the 5-HT2 receptor-mediated contraction. High concentrations of 5-HT in the presence of high concentrations of ICS 205-930, generated significantly attenuated contractile tension in rings from TRX rats.
Conclusions. The elimination of a significant difference in the PTU and CON treatment groups in the denuded tissue as compared to the intact tissue, suggests an enhanced 5-HT-mediated release of endothelial derived relaxing factor (EDRP) in PTU rats and reduced release in TRX rats. An incre ase in sensitivity in the denuded tissues, but not in the intact tissues, suggests an enhanced responsiveness of a 5-HT receptor subtype subserving contraction. The significant effect of micromolar concentrations of ICS 205-930 suggests that an increased contractile response in the
TRX group, in light of the apparent lack of 5-HT3 sites in this tissue, may be mediated, in part, by a novel serotonergic receptor mediating contraction. Alternatively, this effect may reflect activity of the ligand at 5-HT1 or 5-HT2
receptors differentially sensitized by thyropathology. These data suggest that
thyropathological alterations in 5-HT1 or 5-HT2 receptor subtype-mediated responses occur in rat thoracic aorta
- …
