bluuebunny/crossref_metadata_2025_split huggingface dataset:
The planar waveguide
Authors: Blood Peter 
Published: November 2015

Abstract
The planar waveguide controls the overlap of the laser mode with the gain material, which drives the stimulated emission process and determines the divergence of the beam on leaving the laser, important for coupling into external elements such as fibres. Through the optical confinement factor and the optical mode width, the waveguide provides the connection between the gain generated by the gain medium (the material gain) and the amplification experienced by the laser mode (the modal gain). Starting with Maxwell’s equations, this chapter provides an introduction to optical modes of transverse electric and transverse magnetic polarisation in a passive, planar waveguide in the weak guiding approximation. The chapter ends with a short introduction to the internal mode loss in a waveguide.
Quantum confinement
Authors: Blood Peter 
Published: November 2015

Abstract
The properties of the states produced by quantum confinement in double heterostructures are obtained by solving the spatial part of Schrödinger’s equation for a one-dimensional potential well with barriers of finite height. The apparently formidable task of dealing with the very large number of atoms in a solid is greatly simplified by exploiting the periodic nature of crystals through Bloch’s theorem and the envelope functions. Schrödinger’s equation gives, first, the wavefunctions that are used to calculate transition rates via the matrix element and, second, the energies of the confined states and hence the photon energies at which light interactions occur. This is used to develop simple models for the energy states in quantum dots with rectangular and parabolic potential profiles. Quantum wells provide confinement in only one dimension. Freedom in the other two dimensions produces a continuum of states characterised by a density-of-states function.
Gain and emission in quantum dots
Authors: Blood Peter 
Published: November 2015

Abstract
The absorption, gain, and spontaneous emission spectra due to optical transitions in a layer of quantum dots in the slab waveguide of a laser are derived in terms of the dipole matrix element and optical cross section of the dots. This leads to the relation between peak modal gain and intrinsic spontaneous recombination current that is at the heart of device design. Injection lasers use self-assembled dots and so an inhomogeneous distribution of dot sizes, and therefore confined state energies, is a fact of life: this inhomogeneous broadening influences the shape of the spectra. The electron occupation of the states in each dot is determined by capture and emission of carriers injected into the wetting layer. The use of thermal distributions specified by Fermi functions and random population of dots are considered.
Rate equations for dot state occupation
Authors: Blood Peter 
Published: November 2015

Abstract
Rate equations for electrons in dot states can be used to avoid the assumption that electrons are distributed thermally according to Fermi functions. The equations treat the processes of capture and emission of electrons from and to the wetting layer, and of recombination between conduction and valence dot states. Electron capture and emission are controlled by generation and absorption of phonons, and the rate equations are solved in the steady states for a dot system in equilibrium with a Bose–Einstein phonon energy distribution. At high temperature, when the emission rate to the wetting layer exceeds the recombination rate, a thermal, Fermi electron distribution is established, whereas at low temperature, where the emission rate is very slow compared with the recombination rate, the occupation probability of dot states is independent of their energy. This is the random population regime.
Optical transitions in quantum wells
Authors: Blood Peter 
Published: November 2015

Abstract
Optical transitions in quantum wells occur between closely spaced states associated with unconfined motion in the plane of the well within sub-bands formed by confinement across the well. The energy spacing of the unconfined states is much less than the homogeneous linewidth, so the transition rate is given by Fermi’s Golden Rule. Initial and final states must have the same in-plane k-vector (k-selection) and this leads to definition of the transition density. The transition probability is also determined by the overlap integral between initial and final confined state envelope functions, which limits transitions in rectangular wells to sub-bands of the same index. Confinement also produces polarisation dependence of the momentum matrix element, which depends upon whether the valence band is light or heavy hole in character. Expressions are derived for modal gain and spontaneous emission together with the spectrally integrated emission rate at low carrier density using the Boltzmann approximation.
Gain and recombination current in quantum wells
Authors: Blood Peter 
Published: November 2015

Abstract
Examples of typical quantum well gain and spontaneous emission spectra are used to obtain the gain–current relation between peak gain and radiative recombination current, and its temperature dependence, which provide the basis for laser design. The influence of elastic strain and its benefits for laser operation are considered, as are the effects of non-parabolic bands. The effects of band gap narrowing, Coulomb enhancement of gain, and wavefunction dephasing are described, all due to interactions between the large number of carriers present in a working laser device.
Rate equations for laser operation
Authors: Blood Peter 
Published: November 2015

Abstract
Rate equations for the electron and photon populations provide insight into the variation of light output with current and the high-frequency modulation response of the laser. Above threshold the average photon lifetime exceeds the cavity round-trip time. The steady-state solution of these equations shows that the gain never becomes exactly equal to the optical loss, as assumed in the traditional description of threshold, the small difference being made up by the spontaneous emission coupled into the lasing mode given by the spontaneous emission factor. Steady-state solutions are also obtained for quantum dot lasers in the random population regime, where quasi-equilibrium is not established, by solving electron, photon, and phonon coupled rate equations. Rate equations also give the small signal modulation response of the laser and the resonance frequency, including the influence of carrier transport in quantum well devices. The chapter ends with remarks on what constitutes evidence for laser action.
Device structures
Authors: Blood Peter 
Published: November 2015

Abstract
The operation of a laser is influenced by its structure as well as the characteristics of the gain region. The simplest structure is a Fabry–Perot laser that embodies a slab waveguide and feedback by reflection at the end facets. Some lasers use optical feedback from Bragg gratings to improve control of the wavelength. General properties of gratings and specification of the Bragg wavelength are described. Devices with the axis of the cavity in the plane of the epitaxial layers are termed ‘in-plane lasers’ wherein the light propagates along the gain layer and is emitted from the edge of the chip; examples include ridge waveguide lasers, distributed feedback lasers and distributed Bragg reflector lasers. By contrast, in vertical-cavity surface-emitting lasers (VCSELs) the light propagates perpendicular to the plane of the gain layer between two closely spaced multilayer Bragg reflectors. The threshold condition for each of these structures is considered.
Threshold and the light–current characteristic
Authors: Blood Peter 
Published: November 2015

Abstract
The light–current characteristic is the most basic measurement that can be made of the performance of a laser diode, giving its threshold current and external efficiency. For conventional laser diodes a threshold in this characteristic is usually adequate evidence that laser action has been achieved. The contributions to the threshold current of real devices by current spreading, non-radiative recombination by Shockley–Read–Hall (SRH) and Auger processes, and carrier leakage over heterobarriers are described. These are not usually included in theoretical calculations of gain–current characteristics. The information that can be extracted from the threshold current density alone is limited; however, systematic measurements as a function of cavity length can give greater insight into operation of the device, for example in certain circumstances analysis of the differential quantum efficiency provides a value for the optical mode loss. Analysis of the characteristics of quantum dot and well devices is described.
‘Diables incarnez, Machiavelistes, heretiques’: The Villains of Pierre Matthieu's
La Guisiade
Reconsidered
Authors: Patterson Jonathan 
Published: November 2015

Abstract

This article proposes a new reading of Pierre Matthieu's
La Guisiade
(1589), a polemical tragedy written at the height of France's Wars of Religion (1562–98).
La Guisiade
constitutes an incandescent response to the assassination on 23 December 1588 of the Duc de Guise, the charismatic leader of the uncompromising ultra-Catholic faction (the Ligue) on the verge of toppling France's much-maligned monarch, Henri III. Matthieu was a militant
ligueur
when he composed
La Guisiade
, seeking to vilify those he deemed responsible for Guise's murder: the king, his various
mignons
, and his malevolent counsellors. This article will show how the language of villainy that pervades
La Guisiade
has much in common — and more so than previously assumed — with the inflammatory pamphlets (
libelles
) circulated by the Ligue in the late 1580s and early 1590s. Matthieu's hybrid tragedy combines the vitriolic rhetoric of a pamphleteer with a humanist's classicizing sensibility. Viewed as such, it becomes necessary to question the scholarly orthodoxy that Matthieu's villains are predominantly ‘Machiavellian’. Instead, Machiavelli is but one symbol of
ligueur
hatred alongside other deeply reviled figures, including the Huguenot, the Turk, the
politique
, and the sorcerer, whose villainy is conceptualized as mutually reinforcing.
Hydroxymethyluracil modifications enhance the flexibility and hydrophilicity of double-stranded DNA
Authors: Carson Spencer , Wilson James , Aksimentiev Aleksei , Weigele Peter R. , Wanunu Meni 
Published: November 2015

AbstractOxidation of a DNA thymine to 5-hydroxymethyluracil is one of several recently discovered epigenetic modifications. Here, we report the results of nanopore translocation experiments and molecular dynamics simulations that provide insight into the impact of this modification on the structure and dynamics of DNA. When transported through ultrathin solid-state nanopores, short DNA fragments containing thymine modifications were found to exhibit distinct, reproducible features in their transport characteristics that differentiate them from unmodified molecules. Molecular dynamics simulations suggest that 5-hydroxymethyluracil alters the flexibility and hydrophilicity of the DNA molecules, which may account for the differences observed in our nanopore translocation experiments. The altered physico-chemical properties of DNA produced by the thymine modifications may have implications for recognition and processing of such modifications by regulatory DNA-binding proteins.
An Anesthesiologist’s Perspective on the History of Basic Airway Management
Authors: Matioc Adrian A. 
Published: November 2015

AbstractAbstract
Basic airway management modern history starts in the early 18th century in the context of resuscitation of the apparently dead. History saw the rise and fall of the mouth-to-mouth and then of the instrumental positive-pressure ventilation generated by bellows. Pulmonary ventilation had a secondary role to external and internal organ stimulation in resuscitation of the apparently dead. Airway access for the extraglottic technique was to the victim’s nose. The bellows-to-nose technique was the “basic airway management technique” applicable by both medical and nonmedical personnel. Although the techniques had been described at the time, very few physicians practiced glottic (intubation) and subglottic (tracheotomy) techniques. Before the anesthetic era, positive-pressure ventilation was discredited and replaced by manual negative-pressure techniques. In the middle of the 19th century, physicians who would soon administer anesthetic gases were unfamiliar with the positive-pressure ventilation concept.
The modern history of basic airway management started in the early 18th century. The preanesthetic era (1700 to 1846) saw the rise and fall of the positive pressure ventilation and its replacement with negative pressure ventilation.
A Longitudinal Examination of Postural Impairments in Children With Mild Traumatic Brain Injury: Implications for Acute Testing
Authors: Rhine Tara , Quatman-Yates Catherine , Clark Ross A. 
Published: November 2015

Objective:
To examine how postural control changes following pediatric mild traumatic brain injury.

Setting:
Urban pediatric emergency department.

Participants:
Children 11 to 16 years old who presented within 6 hours of sustaining mild traumatic brain injury.

Design:
Prospective observational cohort followed for 1 month.

Main Measures:
Total center of pressure path velocity and path velocity within distinct frequency bands, ranging from moderate to ultralow, were recorded by the Nintendo Wii Balance Board during a 2-legged stance. Measurements were recorded in 2 separate tests with eyes open and closed. The scores of the 2 tests were compared, and a Romberg quotient was computed.

Results:
Eleven children were followed for 1 month postinjury. The ultralow frequency, which reflects slow postural movements associated with exploring stability boundaries, was lower (p = .02) during the eyes closed stance acutely following injury. The Romberg quotient for this frequency was also significantly lower acutely following injury (p = .007) than at 1 month.

Conclusion:
Following mild traumatic brain injury, children acutely demonstrate significantly more rigid sway patterns with eyes closed than with eyes open, which were highlighted by the Romberg quotient. The Romberg quotient could allow for accurate identification and tracking of postural instability without requiring knowledge of preinjury balance ability.
Faith, free choice and the FBI
Authors: Schwarzkopf Stefan 
Published: November 2015

Purpose– This paper aims to review the life and work of one of America’s earliest social researchers, Robert Staughton Lynd (1892-1970). In doing so, it also re-introduces Lynd’s seminal Middletown studies to a wider audience within academic consumer research.Design/methodology/approach– Using the historical-biographical method, light is shed on the developments that led to the publication of the Middletown studies and on the way these studies were received by various audiences.Findings– The critical impetus of interwar social researcher Lynd was to some extent an outcome of his own entanglement with professional marketing and advertising, and of his Protestant religiosity. This insight has important bearings for critical consumer research as well as consumer culture theory today.Research limitations/implications– Market and consumer research comes in many forms. Throughout its history, market and consumer research benefitted from and overlapped with the rise of social research. To fully understand the social and political implications of their work, market and consumer researchers need to have firm knowledge of this interaction with the social sciences and with religious movements in a secular society.Originality/value– Very little is known about the interaction between Robert Lynd’s social research and the sphere of market and consumer research. This interaction is studied by drawing on the secondary literature and on archival sources.
From basket to shopping bag
Authors: Hagberg Johan , Normark Daniel 
Published: November 2015

Purpose– This study aims to follow the gradual transformation of consumer mobility in mid-20th-century Sweden in connection with the introduction of self-service retailing.Design/methodology/approach– The paper is based on an analysis of the magazineICA-Tidningen, published by the major Swedish retailer ICA, for the period from 1941 to 1970.Findings– The paper describes the transformation of consumer mobility as a set of interrelated changes that involved both retailers and consumers, the interrelationship between modes of transport and container technologies and how self-service not only transformed the interior of retail stores but also had more far-reaching implications.Originality/value– When attempting to understand the reconfiguration of shopping practices in the 20th century, there is a tendency to focus on large infrastructural changes. These studies tend to overlook gradual, mundane and everyday translations. This paper contributes methodological tools and analyses that account for such mundane transformations.
Forgotten classics:The Business of Advertising, by Earnest Elmo Calkins (1915)
Authors: Beard Fred 
Published: November 2015

Purpose– The purpose of this paper is to review and summarize Earnest Elmo Calkins’sThe Business of Advertisingand to assess its status as a legitimate forgotten classic of the marketing literature.Design/methodology/approach–The Business of Advertisingis reviewed, summarized and placed in an historical context.Findings– Written during a key period in the history of mass marketing and national brand advertising, Calkins’s work represents a valuable primary source for marketing and advertising historians, especially those interested in marketing industry structures and relationships. Calkins was an influential figure in the development of the modern advertising agency, and his beliefs and approaches in regard to marketing research, campaign planning, branding, message strategy and creativity anticipated some late-twentieth-century approaches and remain highly relevant.Originality/value–The Business of Advertisingwas the object of a single-paragraph review at the time of its publication in 1915, and a short trade journal review appeared not long ago (Lamons, 2000). A more thorough and historically sensitive assessment of Calkins’s forgotten classic reveals some fresh insights into the book and the influential beliefs of the man who was eulogized by trade journalAdvertising Age(1964) as a “giant of creative advertising”.
A Limitless Urban Theory? A Response to Scott and Storper's ‘The Nature of Cities: The Scope and Limits of Urban Theory'
Authors: Mould Oli 
Published: November 2015

AbstractThe recent article in this journal by Scott and Storper (2015) suggested that the field of urban studies currently contains a multitude of varied theoretical viewpoints and argued for a unified general urban theory encompassing all urban scholarly work. Their proposal is that such a theory is based upon a foundational understanding of agglomeration and clustering. This response counter‐argues this, suggesting that such a proposal leaves urban theory too instrumental, deterministic and economistic. Moreover, Scott and Storper argue that there is a need to isolate the urbanization process from a wider suite of social, cultural and economic processes in which the urban is said to be ‘embedded'. If we are to embrace a unified urban theory, however, it should be one which views cities as differing intensities of an urbanization process, and does not try to draw arbitrary boundaries about what is and what is not a city. If we are to strive for a general urban theory, then it would be far more beneficial to champion an ontology of an urbanization process with varying degrees of (de)intensification.
Nondestructive Biological Evidence Collection with Alternative Swabs and Adhesive Lifters
Authors: Plaza Dane T. , Mealy Jamia L. , Lane J. Nicholas , Parsons M. Neal , Bathrick Abigail S. , Slack Donia P. 
Published: November 2015

AbstractIn forensic science, biological material is typically collected from evidence via wet/dry double swabbing with cotton swabs, which is effective but can visibly damage an item's surface. When an item's appearance must be maintained, dry swabbing and tape‐lifting may be employed as collection techniques that are visually nondestructive to substrates' surfaces. This study examined the efficacy of alternative swab matrices and adhesive lifters when collecting blood and fingerprints from glass, painted drywall, 100% cotton, and copy paper. Data were evaluated by determining the percent profile and quality score for each STR profile generated. Hydraflock® swabs, BVDA Gellifters®, and Scenesafe FAST™ tape performed as well as or better than cotton swabs when collecting fingerprints from painted drywall and 100% cotton. Collection success was also dependent on the type of biological material sampled and the substrate on which it was deposited. These results demonstrated that alternative swabs and adhesive lifters can be effective for nondestructive DNA collection from various substrates.
Compositional Factors that Influence Lipid Peroxidation in Beef Juice and Standard Sausages
Authors: Yi Gu , Haug Anna , Nordvi Berit , Saarem Kristin , Oostindjer Marije , Langsrud Øyvind , Egelandsdal Bjørg 
Published: November 2015

AbstractIn order to identify how different additives influenced lipid peroxidation formation, a sausage only using beef juice as pigment source and a standard beef–pork meat sausage were studied. The effects of different additives, including fish oil, myoglobin, nitrite, clove extract, and calcium sources on oxidation and sensory properties were examined. Both sausage systems were stored in 3 different manners prior to testing: (1) frozen immediately at −80 °C; (2) chilled stored for 2.5 weeks followed by fluorescent light illumination at 4 °C for another 2 wk; (3) frozen at −20 °C for 5 mo. The frozen group 3 showed the highest peroxide formation and thiobarbituric acid reactive substances (TBARS) for both sausage systems. Unpolar peroxides dominated in both systems. The clove extract could offset the peroxide formation from myoglobin/beef juice and/or fish oil, but the addition of clove flavor was recognized by the sensory panelists. Calcium addition reduced lipid peroxide formation. Added nitrite and fish oil seemed to interact to stimulate nitroso‐myoglobin formation. Nitrite was identified to interact with clove addition and thereby, relatively speaking, increased TBARS. The 2 sausage systems generally ranked the additives similarly as pro– and antioxidants.