Quantum theory of spin waves in finite chiral spin chains

We calculate the effect of spin waves on the properties of finite-size spin chains with a chiral spin ground state observed on biatomic Fe chains deposited on iridium(001). The system is described with a Heisenberg model supplemented with a Dzyaloshinskii-Moriya coupling and a uniaxial single ion anisotropy that presents a chiral spin ground state. Spin waves are studied using the Holstein-Primakoff boson representation of spin operators. Both the renormalized ground state and the elementary excitations are found by means of Bogoliubov transformation, as a function of the two variables that can be controlled experimentally, the applied magnetic field and the chain length. Three main results are found. First, because of the noncollinear nature of the classical ground state, there is a significant zero-point reduction of the ground-state magnetization of the spin spiral. Second, there is a critical external field from which the ground state changes from chiral spin ground state to collinear ferromagnetic order. The character of the two lowest-energy spin waves changes from edge modes to confined bulk modes over this critical field. Third, in the spin-spiral state, the spin-wave spectrum exhibits oscillatory behavior as function of the chain length with the same period of the spin helix.

Aggressive incidents inside a Montreal barroom involving patrons, barmaids and bouncers : a micro level examination of routine activity theory

Objectives: This article further examines the phenomenon of aggression inside barrooms by relying on the “bouncer-ethnographer” methodology. The objective is to investigate variations in aggression through time and space according to the role and routine of the target in a Montreal barroom. Thus, it provides an examination of routine activity theory at the micro level: the barroom. Methods: For a period of 258 nights of observation in a Canadian barroom, bouncers completed reports on each intervention and provided specific information regarding what happened, when and where within the venue. In addition, the bouncer-ethnographer compiled field observations and interviews with bar personnel in order to identify aggression hotspots and “rush hours” for three types of actors within barrooms: (a) bouncers, (b) barmaids and (c) patrons. Findings: Three different patterns emerged for shifting hotspots of aggression depending on the target. As the night progresses, aggressive incidents between patrons, towards barmaids and towards bouncers have specific hotspots and rush hours influenced by the specific routine of the target inside the barroom. Implications: The current findings enrich those of previous work by pointing to the relevance of not only examining the environmental characteristics of the barroom, but also the role of the target of aggression. Crime opportunities follow routine activities, even within a specific location on a micro level. Routine activity theory is thus relevant in this context, because as actors in differing roles follow differing routines, as do their patterns of victimization.

Restoring Order in Global Health Governance: Do Metagovernance Norms Affect Interorganizational Convergence? CES Open Forum Series #23, 2014-2015

This paper theorizes about the convergence of international organizations in global health governance, a field of international cooperation that is commonly portrayed as particularly hit by institutional fragmentation. Unlike existing theories on interorganizationalism that have mainly looked to intra- and extraorganizational factors in order to explain why international organizations cooperate with each other in the first place, the paper is interested in the link between causes and systemic effects of interorganizational convergence. The paper begins by defining interorganizational convergence. It then proceeds to discuss why conventional theories on interorganizational- ism fail to explain the aggregate effects of convergence between IOs in global (health) governance which tend to worsen rather than cushion fragmentation — so-called "hypercollective action" (Severino & Ray 2010). In order to remedy this explanatory blind-spot the paper formulates an alternative sociological institutionalist theory on interorganizational convergence that makes two core theoretical propositions: first that emerging norms of metagovernance are a powerful driver behind interorganizational convergence in global health governance, and secondly that IOs are engaged in a fierce meaning-struggle over these norms which results in hypercollective action. In its empirical part, the paper’s core theoretical propositions are corroborated by analyzing discourses and practices of interorganizational convergence in global health. The empirical analysis allows drawing two far-reaching conclusions. On the one hand, interorganizational harmonization has emerged as a largely undisputed norm in global health which has been translated into ever more institutionalized forms of interorganizational cooperation. On the other, discourses and practices of interorganizational harmonization exhibit conflicts over the ordering principles according to which the policies and actions of international organizations with overlapping mandates and missions should be harmonized. In combination, these two empirical findings explain why interorganizational convergence has so far failed to strengthen the global health architecture.

Narrative of the expedition of an American squadron to the China Seas and Japan : performed in the years 1852, 1853, and 1854, under the command of Commodore M.C. Perry, United States Navy, by order of the government of the United States /

Includes indexes.

On the theory of the moon : and on the pertubations of the planets /

Issued in 11 pts., 1833-1861.

Algae britannicae : or, Descriptions of the marine and other inarticulated plants of the British Islands, belonging to the order Algae /

Includes bibliographical references and index

On the theory of the moon, and on the perturbations of the planets /

A new edition, 1834 (x, 115, [1], 15, xxxii p.) forms the first part of the author's treatise on this subject, issued in 10 parts, 1834-61.

Reflections upon learning : wherein is shewn the insufficiency thereof, in its several particulars : in order to evince the usefulness and necessity of revelation /

Publisher's advertisements: [2] p. at end.

Report of the Committee of Claims, to whom was recommitted, on the 5th of December last, the petition of Henry Hill, and the several reports thereon, with instruction "To report a statement of the facts relative to the demands against which the United States have indemnified General Greene, as surety of John Banks." : 14th February, 1798, committed to a committee of the whole House, on Monday next. : (Published by order of the House of Representatives.)

Signatures: [A]⁴ B⁴.

Groups of order pm which contain cyclic subgroups of order pm-3,

Mode of access: Internet.

National Labor Relations Board petitioner v. National Maritime Union of America, affiliated with the Congress of Industrial Organizations, and Joseph Curran, Jack Lawrenson, Josh Lawrence, Chester Young, Harold McCormick, Michael McBride, and Charles Monroe, respondents; on petition for enforcement of an order of the National Labor Relations Board; brief for the National Labor Relations Board.

Cover title.

The participatory mind : a new theory of knowledge and of the universe /

"We have taken IQ tests but, strangely, no Compassion Aptitude Tests (CATs). Yet mind and emotions need to be seen as two different parts of the same spectrum, says holistic thinker Henryk Skolimowski, if the human psyche, having taken an unprecedented battering this century, is to be mended. This cannot be accomplished, however, either through the offices of dusty philosophical treatises or popular psychological fixes, only by our arriving at a new way of looking at the world." "In a Grand Theory of participatory mind that builds on the insights of such thinkers as Teilhard de Chardin and Bergson as well as contemporaries Dobzhansky and Bateson, Skolimowski points to a new order, one brought about by a Western mind returning to, then reintegrating, the spiritual. This quest for fresh perspectives, as we approach the twenty-first century, has now become 'the hallmark of our times'."--BOOK JACKET.

Making the 2004 Constitution of Afghanistan: A History and Analysis Through the Lens of Coordination and Deferral Theory

Thesis (Ph.D.)--University of Washington, 2016-06

Developments in the Theory of X-ray Absorption and Compton Scattering.

Thesis (Ph.D.)--University of Washington, 2016-06

A census of critical sets in the Latin squares of order at most six

A critical set in a Latin square of order n is a set of entries from the square which can be embedded in precisely one Latin square of order n, Such that if any element of the critical set. is deleted, the remaining set can be embedded, in more than one Latin square of order n.. In this paper we find all the critical sets of different sizes in the Latin squares of order at most six. We count the number of main and isotopy classes of these critical sets and classify critical sets from the main classes into various strengths. Some observations are made about the relationship between the numbers of classes, particularly in the 6 x 6 case. Finally some examples are given of each type of critical set.