bluuebunny/crossref_metadata_2025 huggingface dataset:
Kryotherapie in der Behandlung ausgedehnter Lidpapillome
Authors: Termühlen Julia , Diener Raphael , Eter Nicole , Grenzebach Ulrike
Published: January 2019

Hintergrund Die Kryotherapie ist ein destruierendes Verfahren und stellt eine wichtige Therapieoption zur chirurgischen Lidtumorexzision dar.

Befunde Wir berichten über eigene Erfahrungen in der Anwendung der Kältebehandlung bei außergewöhnlich großen Oberlidpapillomen, die mittels Kontakt- und Sprühverfahren therapiert wurden.

Ergebnis/Diskussion Durch den Einsatz der Kryotherapie lassen sich ausgedehnte Papillome behandeln. Während eine chirurgische Exzision in einigen Fällen mit einem Verlust der Oberlidfunktion einhergeht, stellt die Kältebehandlung ein alternatives Verfahren dar. Durch den Erhalt von Kollagenstrukturen werden gute funktionelle und ästhetische Ergebnisse erzielt.
Two examples of exact calculations of the adiabatic invariant for charged particle motion in non-uniform axisymmetric magnetic fields
Authors: Kabin K.
Published: January 2019

This paper discusses the calculation of the adiabatic invariant of a charged particle moving in an axisymmetric magnetic field with straight field lines. This calculation can be reduced to quadratures, and in several cases, the exact analytical results can be obtained. In particular, an exact expression is obtained for the charged particle motion in the equatorial field of a magnetic dipole, which can have important applications to the high-order guiding center theory for the particles in the terrestrial radiation belts. Another closed-form analytical result corresponds to magnetic field intensity which is inversely proportional to the radius. The results represent an extension of the classical series expansions of Kruskal for these specific magnetic fields.
Enspara: Modeling molecular ensembles with scalable data structures and parallel computing
Authors: Porter J. R. , Zimmerman M. I. , Bowman G. R.
Published: January 2019

Markov state models (MSMs) are quantitative models of protein dynamics that are useful for uncovering the structural fluctuations that proteins undergo, as well as the mechanisms of these conformational changes. Given the enormity of conformational space, there has been ongoing interest in identifying a small number of states that capture the essential features of a protein. Generally, this is achieved by making assumptions about the properties of relevant features—for example, that the most important features are those that change slowly. An alternative strategy is to keep as many degrees of freedom as possible and subsequently learn from the model which of the features are most important. In these larger models, however, traditional approaches quickly become computationally intractable. In this paper, we present enspara, a library for working with MSMs that provides several novel algorithms and specialized data structures that dramatically improve the scalability of traditional MSM methods. This includes ragged arrays for minimizing memory requirements, message passing interface-parallelized implementations of compute-intensive operations, and a flexible framework for model construction and analysis.
Surfactant-induced migration of a spherical droplet in non-isothermal Stokes flow
Authors: Sharanya V. , Sekhar G. P. Raja , Rohde Christian
Published: January 2019

The motion of viscous droplet in an unbounded arbitrary (non-axisymmetric) Stokes flow under the combined influence of bulk-insoluble surfactant Marangoni stresses and thermal Marangoni stresses is studied analytically in two limiting cases, namely, low and high surface Péclet numbers. This work considers a more general model where the nonlinear variation of the interfacial tension is due to both thermal and surfactant gradients. It is well known that linear thermocapillary stresses assist migration of the droplet, while surfactants resist when the ambient thermal field is along the direction of the ambient hydrodynamic field. We have observed that this behavior prevails even when a nonlinear combination of thermal and surfactant stresses is considered. However, since the retardation due to surfactants is marginal, when combined linear thermal and linear surfactant stresses are superimposed, the thermal forces dominate the overall migration. The present work derives closed form expressions for the drift and the migration velocity where the capillary stresses can be non-axisymmetric and along the axial or transverse direction. This would enable one to design parameter combinations to control the droplet migration for possible use in various applications. Since the results are for any arbitrary ambient flow, we have provided the corresponding analysis when the ambient hydrodynamic flow is due to Poiseuille flow. The corresponding results when the thermal gradients are axial or transverse to the flow direction are discussed. In this regard, we contribute some important findings on the cross migration of the droplet. We observe that the droplet can move towards or away from the centerline depending on the critical thermal Marangoni number. We have seen the variation of velocity fields in different planes when the ambient flow field is a Poiseuille flow. Furthermore, we have computed the power (rate of work) on the surface of the droplet. The obtained analytical results are compared with the existing literature in all possible limiting cases. Finally, we draw a striking analogy with flow through porous media that the centroid of the droplet migrates with a velocity that is thought of as the volume averaged velocity inside a resistive medium.
Crossover from hopping to band-like transport in crystalline organic semiconductors: The effect of shallow traps
Authors: Dong Jingjuan , Wu Changqin
Published: January 2019

We show a crossover from coherent to incoherent behavior of charge transport in crystalline organic semiconductors by considering the effect of shallow traps within the dynamical disorder model. The mixed quantum-classical system is treated by the Ehrenfest dynamics method complementing with instantaneous decoherence corrections and energy relaxation, which has been shown to properly make the system close to equilibrium. The shallow traps, which are incorporated by a static diagonal disorder, are shown to play a central role in the crossover. Temperature dependence of charge-carrier mobility is shown to be changed from being negative to positive with the strength of shallow traps increasing, which implies that there is a crossover from hopping to band-like transport. A higher electric field helps to recover the charge-carrier band-like transport behavior from the traps-caused hopping transport. In this way, a unified physical picture of the charge transport in crystalline organic semiconductors is proposed.
Dielectric and ferroic properties of metal halide perovskites
Authors: Wilson Jacob N. , Frost Jarvist M. , Wallace Suzanne K. , Walsh Aron
Published: January 2019

Halide perovskite semiconductors and solar cells respond to electric fields in a way that varies across time and length scales. We discuss the microscopic processes that give rise to the macroscopic polarization of these materials, ranging from the optical and vibrational response to the transport of ions and electrons. The strong frequency dependence of the dielectric permittivity can be understood by separating the static dielectric constant into its constituents, including the orientational polarization due to rotating dipoles, which connects theory with experimental observations. The controversial issue of ferroelectricity is addressed, where we highlight recent progress in materials and domain characterization but emphasize the challenge associated with isolating spontaneous lattice polarization from other processes such as charged defect formation and transport. We conclude that CH3NH3PbI3 exhibits many features characteristic of a ferroelastic electret, where a spontaneous lattice strain is coupled to long-lived metastable polarization states.
Investigation of wire-array Z-pinches by laser probing diagnostics
Authors: Ivanov V. V. , Anderson A. A. , Papp D.
Published: January 2019

Laser diagnostics provides powerful tools for the investigation of dense Z-pinches. In this paper, wire-array Z-pinches are investigated at the 1 MA Zebra generator using laser diagnostics at different wavelengths coupled with x-ray diagnostics. Plasma dynamics during the ablation, implosion, and stagnation stages are observed by multiframe diagnostics. Cascading and nonprecursor implosions are studied in wire arrays. Ultraviolet diagnostics allows deep penetration into the Z-pinch plasma at stagnation. End-on probing reveals the complicated structure of the precursor. Strong magnetohydrodynamic instabilities are found in a dense pinch hidden in the trailing plasma. Small-scale instabilities are seen in the Z-pinch plasma with micrometer resolution. Probing of the pinch from four directions shows asymmetrical trailing plasma in some configurations of wire arrays. Faraday rotation diagnostics reveals the magnetic fields and the current distribution in the plasma of the precursor and Z-pinch. Redistribution of current in the trailing plasma is seen during kink and sausage instabilities in the stagnation stage. The formation of micropinches and hot spots in the Z-pinch is analyzed with coupled laser and x-ray diagnostics. Different laser diagnostics allow the study of Z-pinch plasmas in all stages, including fast dynamics and instabilities.
Elastic constants of ice Ih as described by semi-empirical water models
Authors: Franco Pinheiro Moreira Pedro Augusto , Gomes de Aguiar Veiga Roberto , de Koning Maurice
Published: January 2019

Using molecular dynamics simulations, we compute the elastic constants of ice Ih for a set of 8 frequently used semi-empirical potentials for water, namely, the rigid-molecule SPC/E, TIP4P, TIP4P2005, TIP4P/Ice, and TIP5P models, the flexible-molecule qTIP4P/Fw and SPC/Fw models, and the coarse-grained atomic mW potential. In quantitative terms, the mW description gives values for the individual stiffness constants that are closest to the experiment, whereas the explicit-proton models display substantial discrepancies. On the other hand, in contrast to all explicit-proton potentials, the mW model is unable to reproduce central qualitative trends such as the anisotropy in Young’s modulus and the shear modulus. This suggests that the elastic behavior of ice Ih is closely related to its molecular nature, which has been coarse-grained out in the mW model. These observations are consistent with other recent manifestations concerning the limitations of the mW model in the description of mechanical properties of ice Ih.
High temperature thermoelectric properties of laser sintered thin films of phosphorous-doped silicon-germanium nanoparticles
Authors: Xie Kai , Mork Kelsey , Kortshagen Uwe , Gupta Mool C.
Published: January 2019

Silicon-germanium (SiGe) is an important thermoelectric material for high-temperature applications. In this study, we show that the Seebeck coefficient of the laser sintered thin films of phosphorous (P)-doped Si80Ge20 nanoparticles increases from -144.9 μV/K at room temperature to -390.1 μV/K at 873 K. The electrical conductivity increases from 16.1 S/cm at room temperature to 62.1 S/cm at 873 K and demonstrates an opposite trend when compared to bulk nanostructured materials. The thermal conductivity from room temperature to 573 K is essentially constant within the measurement error of our system at ∼1.35 W/m⋅K. Therefore, if the thermal conductivity follows a similar temperature dependent trend as reported in past scientific literature, the figure of merit of the thin film Si80Ge20 is estimated to be 0.60 at 873 K which is comparable to a value of ∼1 for bulk nanostructured materials. This result indicates that thin film P-doped SiGe can provide comparable performance with bulk nanostructured SiGe materials by using nanoparticle laser sintering as an easier, quicker, and more cost-effective processing method.
Research on realization and optimization of communication equipment security engineering circuit for nonlinear system based on fractional differential operator
Authors: Chen Ningning
Published: January 2019

Compared with integral calculus, the fractional differential operator can objectively reveal and describe the physical characteristics of the actual system. For fractional differential operator functions, sufficient conditions for stability of fractional nonlinear systems are given. By accurately adjusting the frequency of the analog input signal and observing and verifying the nonlinear dynamic characteristics of the new system, the simulation experiment of the fractional circuit with different fractional values is carried out, and the circuit simulation can visually observe the evolution of system variables. The research shows that the predictive correction method numerically simulates the fractional-order system, and the phase diagram of the chaotic attractor of the system is obtained. The simulation results show that the minimum order of chaos in the fractional hyperchaotic system is 2.8. The research shows that the simulation of the nonlinear system and its circuit implementation show the effectiveness of the circuit simulation method of the fractional-order chaotic system and the feasibility of circuit implementation.
New approach characterizes electronic angular momentum decoupling schemes of autoionized ions
Authors: Liebendorfer Adam
Published: January 2019

Combining a crossed molecular beam with mass spectrometry and hemispherical electron analysis, a novel technique provides transition state and geometrical information on collision reactions.
Flexible N-Donor Ligands Direct the Structural Characteristics of CoII Complexes: Syntheses, Structures, and Magnetic Properties
Authors: Yang Yu-Ting , Tu Chang-Zheng , Xu Xiao-Lin , Xu Li-Li , Yan Bang-Ling , Cheng Fei-Xiang
Published: January 2019

Solvothermal reactions of 3,3′,5,5′-biphenyltetracarboxylic acid (H4BPTC) and cobalt(ii) ions in the presence of two different flexible N-donor ancillary ligands afford two novel coordination polymers, {[Co(BPTC)0.5(bix)]·H2O}n (1), {[Co(BPTC)0.5(bpp)]·3H2O}n (2) (bix=1,4-bis(imidazol-1-ylmethyl)benzene; bpp=1,3-bis(4-pyridyl)propane). Their structures have been determined by elemental analyses, IR spectra, single-crystal X-ray diffraction analyses, and powder X-ray diffraction. The pillared layered framework of 1 can be simplified to a (4,6)-connected net with a Schläfli symbol of (44·62)(44·69·82). Complex 2 manifests a bilayered structure, and can be simplified to a (4,4)-connected net with a Schläfli symbol of (55·8)(54·62). The thermal stabilities of both complexes and the magnetic behaviours of 1 are also discussed.
Language Planning as Nation Building
Authors: Rutten Gijsbert
Published: January 2019

The decades around 1800 constitute the seminal period of European nationalism. The linguistic corollary of this was the rise of standard language ideology, from Finland to Spain, and from Iceland to the Habsburg Empire. Amidst these international events, the case of Dutch in the Netherlands offers a unique example. After the rise of the ideology from the 1750s onwards, the new discourse of one language–one nation was swiftly transformed into concrete top-down policies aimed at the dissemination of the newly devised standard language across the entire population of the newly established Dutch nation-state. Thus, the Dutch case offers an exciting perspective on the concomitant rise of cultural nationalism, national language planning and standard language ideology.
This study offers a comprehensive yet detailed analysis of these phenomena by focussing on the ideology underpinning the new language policy, the institutionalisation of this ideology in metalinguistic discourse, the implementation of the policy in education, and the effects of the policy on actual language use.
Present perfect or simple past?
Authors: Farghal Mohammed
Published: January 2019

The present study aims to examine the claim that the preverbal particleqadin the perfective is an aspectual marker of near past in Arabic, hence it corresponds to the present perfect in English. The authentic translational corpus drawn from two works (journalistic/scientific and literary discourse) clearly indicates that the preverbalqadis employed as a cohesive marker whose main function is to smooth and naturalize Arabic discourse. The study demonstrates that the translator’s choice between an Arabic simple past with or withoutqadis governed by the requirements of the flow of discourse rather than by aspectual marking. Failure to account for this discursive function ofqadwhen translating from English into Arabic would in Arabic translations produce cohesion gaps which in English are usually taken care of by punctuation.
“We must unite now or perish!”
Authors: Nartey Mark
Published: January 2019

This paper presents a discourse-mythological analysis of the rhetoric of a pioneering Pan-African and Ghana’s
independence leader, Kwame Nkrumah, drawing on Ruth Wodak’s discourse-historical approach to critical discourse analysis. The
thesis of the paper is that Nkrumah’s discourse, in its focus on the emancipation and unification of Africa, can be characterized
as mythic, a discursive exhortation of Africa to demonstrate to the world that it can better govern itself than the colonizers. In
this vein, the paper analyzes four discursive strategies employed by Nkrumah in the creation and projection of his mythology: the
introduction or creation of new discourse events, presupposition and implication, involvement (the use of indexicals) and lexical
structuring and reiteration. This study is, therefore, presented as a case study of mythic discourse within the domain of
politics.
Corpus-based research on English in Africa
Authors: Fuchs Robert , van Rooy Bertus , Gut Ulrike
Published: January 2019

This chapter provides linguists and students not yet familiar with corpus-based research on varieties of English in Africa with a practical introduction to the field. After explaining the rationale and aims of corpus-based research on varieties of English (in Africa), we introduce methods, tools and resources commonly used and applied in the field in order to provide readers with a point of entry into the field. Most of the corpora and software that are introduced can be obtained free of charge. The software is introduced in a practical way to permit readers to use it in their own research. The application and value of corpus linguistics are exemplified with three case studies. These examples are based in part on previous research, retracing the methodological steps, but are also expanded with more data from across Africa. Case study 1 shows how corpora allow researchers to investigate lexical differences between African varieties of English, arguably an area that is amenable to scholarly inquiry with relatively limited methodological means. Case study 2 considers a grammatical phenomenon, the present perfect in African Englishes, and demonstrates how a corpus tagged for parts of speech permits syntactic analyses. Case study 3 illustrates the analysis of a phonological corpus with an investigation of the optional deletion of the phoneme /h/ in words such as house in Nigerian English. The chapter concludes with recommendations for further reading, allowing readers to explore selected topics in more depth according to their interests.
The purpose, design and use of the Corpus of Nigerian and Cameroonian English Learner Language (Conacell)
Authors: Esimaje Alexandra U.
Published: January 2019

This chapter reports on a new learner corpus project, describes its purpose and design, and demonstrates its use: the error-annotated corpus of 442,939 words of Nigerian and Cameroonian English Learner Language (Conacell) (Esimaje 2016). The aim of the project is to produce a resource for measuring learners’ language development and to enhance the teaching-learning process. The corpus data comprises the language output of 998 students; 383 university and 615 secondary students. The specific uses of the corpus to explore lexical form and tense usages by learners in Nigeria and Cameroon are shown. Corpus analysis reveals, for instance, that the lexical form of capitalisation and tense are hard to learn, and therefore remain learning needs in the contexts.
Introducing a corpus of English(es) spoken in post-independence Namibia
Authors: Steigertahl Helene
Published: January 2019

The possibility of an evolving “Namibian English” was already suggested more than 30 years ago (Chamberlain 1981: 46). However, detailed analyses of the English(es) used in Namibia were only recently initiated (e.g. Otaala 2006; Buschfeld & Kautzsch 2014; Kautzsch & Schröder 2016; Steigertahl 2017). The present chapter adds to previous research on morphosyntactic structures, introducing the Corpus of English(es) Spoken by Black Namibians post Independence (ESBNaPI). First, the Namibian linguistic situation will be introduced before procedures of data collection and methodology will be presented. Afterwards, morphosyntactic examples from the corpus will be given and compared to South African English(es) (SAE) to address potential generalizations of post-Independence English(es). The overall goal is to raise awareness of corpus resources in southern Africa.
The historical corpus of English in Ghana (HiCE Ghana)
Authors: Brato Thorsten
Published: January 2019

This chapter discusses various aspects relevant to the compilation of the Historical Corpus of English in Ghana (HiCE Ghana), a 600,000-word corpus of written Ghanaian English (GhE) from the period 1966 to 1975. The corpus captures written GhE in the early years of its nativization phase and by comparison to the relevant sections of the Ghanaian component of ICE makes it possible to trace structural nativization in real time. The paper addresses the motivation for such a corpus and shows how methodological and theoretical concerns and challenges have affected the final corpus design. The paper is rounded off with contemporary examples of GhE.
Practical corpus linguistics
Authors: Nkemleke Daniel
Published: January 2019

One major contribution of the corpus-based approach to language study is the facility with which linguists can access large amounts of data and search for regularities across text types and varieties of English on the basis of observed frequencies. Such regularities of features, if based on well-designed and/or specialised corpora, can be useful for classroom activities and material design. This chapter describes the basic steps involved in corpus design and corpus exploitation. Section 1 defines the corpus and briefly states the relevance of investigating English second language (ESL) varieties via a corpus. Section 2 describes key steps involved in simple corpus compilation and how students can compile their own corpora for research. Section 3 presents results of two studies on the frequency and use of modals in the corpus of Cameroonian English. These results are intended to illustrate the point that the corpus approach is indispensable if certain types of linguistic information are investigated in a particular variety.
Evaluating explanations for past-time reference with unmarked verb forms in African Englishes
Authors: van Rooy Bertus
Published: January 2019

Previous research suggests that some varieties of English in Africa do not mark the past tense consistently with an inflectional suffix. Various explanations are offered for this state of affairs, including the option of the historical present tense, non-marking because the context already makes clear that the verb denotes a past event, phonological reduction, and limited English language proficiency. This chapter reports on a corpus analysis of spoken conversation in Nigerian English and Black South African English, which indicates that the non-marking of the past tense occurs in about one in every five contexts where an event in the past is represented. However, no convincing support is found for any of the explanations in the previous research on the topic.
Namibian English on the web
Authors: Kautzsch Alexander
Published: January 2019

The present chapter introduces the Corpus of Namibian Online Newspapers (CNamON), which encompasses the contents of seventeen news sources as available on the Internet from May to June 2016. These sources add up to roughly 44 million words of text. The corpus was compiled to facilitate taking a systematic account of the lexical and structural properties of Namibian English, which have not been investigated to date. This chapter focusses on the technical details of the compilation process of CNamON as well as its set-up and its usefulness for linguistic research. To demonstrate the corpus’ potential for analyses on the linguistic levels of lexis and (morpho-)syntax, both a qualitative stock-taking and exemplary quantitative analyses of structural characteristics of English in Namibia are provided.
Capturing the lexicon of Ugandan English
Authors: Isingoma Bebwa , Meierkord Christiane
Published: January 2019

This paper discusses corpus linguistics as one method to investigate the lexicon of Ugandan English, which is characterised by borrowing, calquing, semantic extension, narrowing, and shift. It documents how analysing a well-balanced corpus, such as the Uganda component of the International Corpus of English, allows for a contextualisation of observations made from current uses of English and for an assessment of the textual genres in which such innovations occur. At the same time, it critically discusses the limitations and biases associated with a comparatively small corpus and argues for a multi-method approach that involves using larger, though less well controlled, corpora as well as supplementing corpus analyses with experimental data, which tap into the spread of lexical innovations.
Encoding Motion Events in Mandarin Chinese
Authors: Lin Jingxia
Published: January 2019

This book is a corpus-based description and discussion of how Modern Mandarin Chinese encodes motion events, with a focus on how the distribution of verbal motion morphemes is closely associated with the meanings they lexicalize. The book is not only the first work that proposes a finer-grained classification and diagnostics of Chinese motion morphemes from the perspective of scale structure, but also the first to more comprehensively account for the ordering of Chinese motion morphemes. The findings of this study will not only enrich the literature on motion events, but more importantly, further our understanding of the nature of motion events and the way motion events are conceived and represented in the Chinese language. The major proposals and the cognitive functional approach of this work will also shed light on studies beyond motion. The book will be a valuable resource for scholars interested in motion events, syntax-semantic interface, and typology.
Algebraic hypersurfaces
Authors: Kollár János
Published: January 2019

We give an introduction to the study of algebraic hypersurfaces, focusing on the problem of when two hypersurfaces are isomorphic or close to being isomorphic. Working with hypersurfaces and emphasizing examples makes it possible to discuss these questions without any previous knowledge of algebraic geometry. At the end we formulate the main recent results and state the most important open questions.
In polytocous mammals, weakling neonates, but not their stronger littermates, benefit from specialized foraging
Authors: Skok Janko , Prevolnik Povše Maja
Published: January 2019

Adjusting foraging strategies is a common phenomenon within groups of animals competing for the same resource. In polytocous mammals, neonates concurrently compete for limited milk and alternate between two foraging (suckling) strategies: adaptable exploratory foraging with random sampling of teats, and ordered foraging with a tendency towards exploiting a particular suckling position. Some theoretical (game theory) models have shown that weaker siblings in particular benefit from foraging specialization (suckling order). Neonate piglets establish a well-defined suckling order that develops gradually and fluctuates throughout the lactation period, implying the existence of inter-individual differences in foraging strategies. We therefore analyzed suckling behavior in pigs to determine whether one foraging strategy was more beneficial to neonates in terms of their body weight and foraging environment. We found that intermediate and heavy littermates tended to adjust their suckling strategy according to the foraging environment; however, the selected foraging strategy did not affect their overall growth performance. Lighter individuals that consumed significantly less milk did not greatly alternate their foraging strategy according to the foraging environment, but their growth rate was significantly higher whenever they performed less-exploratory foraging behavior. Although suckling order appeared to be a relatively stable behavioral phenotype, it was beneficial exclusively for weaklings. These results confirm theoretical predictions and indicate that specializing in a suckling position is a beneficial strategy for weaker, light neonates. These findings suggest that physically weaker neonates might have driven the evolution of neonatal foraging specialization.
The Ellestad Protocol
Authors: Ellestad Myrvin H. , Thomas Gregory S.
Published: January 2019

The chapter The Ellestad Protocol reviews the performance of a maximal exercise test from start to finish using the Ellestad protocol as an example. Patient preparation should include caffeine avoidance should a vasodilator myocardial perfusion imaging (MPI) test be necessary secondary to inadequate exercise. A light meal prior to exercise testing is acceptable. The Bruce and Ellestad protocols both begin with a stage each investigator regarded as a warm-up, 3 minutes of exercise at 1.7 mph at a 10% grade. With two minute stages, primarily of increasing grade, the Ellestad protocol is completed approximately one minute earlier than the Bruce protocol. The use of the Borg scale of perceived exertion is helpful in determining a patient’s effort. If ancillary MPI is not being performed, an abrupt stop for a motion-free electrocardiogram (ECG) and then immediately placing the patient supine or semi-supine increases pre-load and, via the law of Laplace, increases left ventricular end-diastolic pressure, myocardial oxygen demand and thus ischemia. ST segment depression is observed earlier in recovery than if a cool-down walk is performed. Case examples are provided.
Interpretation of the ECG during Exercise and Recovery
Authors: Thomas Gregory S. , Samtani Sonia R. , Ellestad Myrvin H.
Published: January 2019

The chapter Interpretation of the ECG During Stress Testing reviews the electrocardiographic changes of ischemia during exercise testing. Normal ECG changes during exercise are reviewed and include the Ta wave of atrial repolarization which is directed in the opposite direction of the P wave. Its duration extends into the ST segment, resulting in a false positive exercise test in some patients. The type, severity and duration of ST depression predicts CAD severity and outcome. Downsloping ST depression is more ominous than horizontal which is worse than upsloping. As Ellestad has long posited, an abnormal ST segment response is >1 mm of downsloping and horizontal and >1.5 mm of upsloping ST depression. The 12 lead ECG leads most predictive of myocardial ischemia are leads V4-6, I, and aVR. ST elevation in leads without Q waves occurs secondary to transmural ischemia and localizes to the stenotic coronary artery.
Exercise Testing in a Limited Resource Environment
Authors: Allam Adel H. A. , Mandour Ali Mohamed A.
Published: January 2019

Using Egypt as an example, the chapter Stress Testing in a Limited Financial Resource Environment reviews how exercise testing can serve as the cornerstone of noninvasive evaluation of coronary artery disease (CAD) in developing countries. Its wide availability, low cost, and safety makes it the test of choice for patients at low to intermediate likelihood of CAD. Proper patient selection and skin preparation, simple and clear patient education, and reassurance as to the purpose of the test and the crucial importance of achieving a near maximal heart rate are necessary to obtain optimal sensitivity and specificity, either as a stand-alone test or in conjunction with cardiac imaging. The use of provisional MPI in patients unable to achieve 10 metabolic equivalents without chest pain or ischemic electrocardiographic changes is reviewed.
Nuclear Cardiology
Authors: Thomas Gregory S. , Wann L. Samuel
Published: January 2019

The Nuclear Cardiology chapter reviews the opportunity to increase sensitivity and specificity of stress testing for the diagnosis of coronary artery disease with exercise or pharmacologic myocardial perfusion imaging (MPI). Case presentations highlight the concepts presented. Based on the extraction fraction of thallium-201 and technetium-99m sestamibi and tetrofosmin, optimal timing of radioisotope injection at near peak exercise is reviewed. The importance of achieving ≥85% of maximal heart rate or an ischemic endpoint and when to convert to vasodilator testing is discussed. Multiple well-tested protocols are reviewed to add exercise to adenosine or regadenoson to minimize adverse effects and improve imaging quality and throughput. Data from the 1,147 patient EXERRT study are reviewed demonstrating that a technetium-99m radioisotope dose ratio of 1:3 is too low for 1-day low-dose rest/high-dose stress MPI secondary to shine through of the resting study into the stress study. A dose ratio minimum of 1:4 is recommended for 1-day low-dose rest/high-dose stress protocols.
Heart Rate Response to Exercise
Authors: Thomas Gregory S.
Published: January 2019

The chapter Heart Rate Response to Exercise reviews the studies performed to estimate a patient’s maximum predicted heart rate. While the commonly used formula (220 – age), developed in 1971, is easy to remember, it underestimates the actual maximum heart rate in older persons. Studies of large sample size have found the maximum heart rate to be relatively independent of sex and physical fitness but to incrementally decline with age. The decrease with age is less than 1 beat per minute per year, however. A more accurate and recommended formula is [(208) – (0.7)(age)] as developed by Tanaka and colleagues.
Stress Testing in Women
Authors: Mehta Puja K. , Isiadinso Ijeoma , Wann L. Samuel
Published: January 2019

The chapter Stress Testing in Women reviews the clear sex-specific differences in the presentation and pathophysiology of ischemic heart disease (IHD). Women tend to have more atypical and more subtle symptoms such as dyspnea or fatigue than men. Symptomatic women are also more likely to have no obstructive coronary artery disease (CAD) on coronary angiography, but still have adverse clinical outcomes. Coronary microvascular dysfunction. Exercise testing is frequently the first test of choice to diagnose IHD in women. When resting electrocardiogram abnormalities precludes exercise testing or exercise testing is inconclusive, stress imaging with echocardiography or myocardial perfusion imaging can be added. Routine stress testing is designed to detect flow-limiting, obstructive CAD. When stress imaging is negative or “falsely positive” in a symptomatic patient, nonobstructive causes of IHD including coronary microvascular dysfunction should be considered.
Stress Testing of Athletes and Those in High-Risk Occupations
Authors: Wann L. Samuel
Published: January 2019

The chapter Stress Testing of Athletes and Those in High Risk Occupations reviews expectations and challenges of exercise testing in amateur athletes, firefighters, police, pilots, and astronauts. Cardiac events, including sudden cardiac death, occurring in amateur athletes are rare and difficult to predict with cost-effective population screening, and routine stress testing is not recommended. However, for higher risk individuals and those in high risk occupations, stress testing may have a role in screening and reassuring individual participants and the public. Abnormal studies may preclude individuals from occupations that require medical clearance.
Sports Medicine and Cardiac Rehabilitation for Coronary and Peripheral Artery Disease Patients
Authors: Thomas Gregory S. , Ellestad Myrvin H.
Published: January 2019

The chapter Sports Medicine and Cardiac Rehabilitation for Coronary and Peripheral Artery Disease (CAD) reviews the benefits and potential risks of physical activity and the opportunity for particular benefit in patients with coronary artery disease and peripheral artery disease (PAD). Longitudinal studies of large populations have found a benefit to habitual exercise on cardiovascular health, including decreasing cardiovascular mortality. A physiologic training effect is not required for benefit. Mild exercise is better than inactivity and increasing activity provides even greater benefit. Athletic training induces expected electrocardiographic changes at rest in athletes. Prescribing exercise with or without an exercise test is discussed in asymptomatic individuals as well as prior to participation in traditional cardiac rehabilitation or a supervised exercise program for patients with peripheral artery disease. PAD patients often do not have classic intermittent claudication yet are able to benefit from exercise therapy.
Stress Testing in Children
Authors: Hattendorf Brandy
Published: January 2019

The chapter Stress Testing in Children reviews the opportunity to evaluate children with congenital and acquired cardiovascular disease. Clinical pediatric exercise testing differs from adult testing in both disease etiology as well as the characteristics of cardiovascular response. Unlike exercise testing in adults, the indications for testing in pediatrics generally are not to evaluate for ischemia. Commonly, pediatric exercise testing is used to evaluate specific signs and symptoms induced or aggravated by exercise, including identification of exercise induced arrhythmias, whereas metabolic testing can provide further patient information regarding cardiac output, maximal oxygen consumption, and lung capacity. Exercise testing can also assess the efficacy of medical or surgical treatments for individual congenital heart disease patients. Functional capacity can be used to determine patient safety for recreational, athletic, and vocational activities. Exercise modification and restrictions are necessary for some patients based on the data provided by exercise testing.
Perspectives on the Future of Stress Testing
Authors: Wann L. Samuel , Thomas Gregory S.
Published: January 2019

The chapter Perspectives on the Future of Stress Testing forecasts changes in the ability to detect atherosclerosis in the form of obstructive and non-obstructive coronary artery disease and ischemia. These will continue to include low cost and widely available exercise testing as well as embracing new technology such as mobile sensors, biomarkers, and genetic testing. Continued advancements in positron emission tomography, cardiac computed tomography, and cardiac magnetic resonance imaging will create new opportunities for better definition of myocardial blood flow and prediction of prognosis. While we will continue to expand our ability to measure greater detail of aspects of cardiac structure, function and metabolism, the humanity of a clinician being at the side of the treadmill while our whole patients exercise to their individual capacity remains a valuable diagnostic, educational and bonding opportunity
Pseudoachondroplasia and Dominant Epiphyseal Dysplasia
Authors: Spranger Jürgen W. , Brill Paula W. , Hall Christine , Nishimura Gen , Superti-Furga Andrea , Unger Sheila
Published: January 2019

This chapter discusses pseudoachondroplasia and dominant epiphyseal dysplasia and explores pseudoachondroplasia, and multiple epiphyseal dysplasia. Each discussion includes major clinical findings, major radiographic features, genetics, major differential diagnoses, and a bibliography.
Mucopolysaccharidoses and Oligosaccharidoses
Authors: Spranger Jürgen W. , Brill Paula W. , Hall Christine , Nishimura Gen , Superti-Furga Andrea , Unger Sheila
Published: January 2019

This chapter discusses mucopolysaccharidoses and oligosaccharidoses and explores dysostosis multiplex, mucopolysaccharidosis IV, mucolipidosis II, and mucolipidosis III. Each discussion includes major radiographic features, major clinical findings, genetics, major differential diagnoses, and a bibliography.
Clinical and Therapeutic Treatise on Hysteria
Authors: Walusinski Olivier
Published: January 2019

The extensive three-volume treatise that Gilles de la Tourette wrote on hysteria is certainly the publication he was most invested in. He scrupulously described the work on hysteria by his teacher Charcot and all the students of the Salpêtrière School. In this way, he acted as a guardian of the dogmas laid down by the Master and transmitted intangibly. Paul Richer, who was older than Gilles de la Tourette, did much to explain the neuropsychological pathology of hysteria, and Gilles de la Tourette highlighted his contribution while not failing to devote much of his text to his own personal work. In this chapter, the author analyzes the first volume on “normal hysteria,” that is, permanent hysterical stigmata, hysterogenic zones, etiology and triggering agents of hysteria, and mental state of hysterics. The chapter also highlights the influence of progressive ideology, whereby hysterical disturbances should be demystified.
Théophraste Renaudot (1586–1653)
Authors: Walusinski Olivier
Published: January 2019

Gilles de la Tourette had a passion for the history of medicine and ideas, with a particular attachment to the city of Loudun, where his family had its roots. In 1884, he published a biography of another Loudun native, Théophraste Renaudot, a seventeenth-century physician who advocated reform in medical studies, calling into question the rigid scholastic method, limited to Hippocratic and Galenic medicine, in order to develop truly clinical practices as well as medical research. This chapter presents this biography and its genesis, Gilles de la Tourette’s hidden debt to Eugène Hatin, and unpublished letters received by Gilles de la Tourette after the book’s publication. Drawing on archival documents, the process Gilles de la Tourette initiated to erect a Renaudot statue in Paris and Loudun is detailed, as is his induction into the Ordre de la Légion d’honneur.
Pulse Oximetry
Authors: Liebling Storm , Langhan Melissa
Published: January 2019

This section focuses on the use of pulse oximetry during procedural sedation and analgesia (PSA). Pulse oximetry is the most common monitoring method used during PSA. It is a noninvasive method for monitoring a patient’s peripheral oxygen saturation (SpO2) of hemoglobin. Its use is recommended in the monitoring of children undergoing various levels of sedation as a means to detect hypoxemia and decrease the likelihood of adverse outcomes, including cardiopulmonary arrest and death. It is a highly reliable modality for detecting oxygen desaturation events. However, understanding its indications and limitations will allow the user to properly identify and manage a desaturation event during PSA.
Solid Organ Biopsies
Authors: Biber Jennifer , Wheeler Jenna
Published: January 2019

While solid organ biopsies are routinely done on adults with only local anesthesia or minimal sedation, children frequently require deep sedation or general anesthesia to achieve acceptable conditions (stillness, anxiolysis, analgesia) to facilitate these procedures. This is more frequently being done with pediatric sedation/anesthesia outside the operating room. Issues unique to sedation for these procedures are pain, the need for relative patient immobility (both during the procedure and following it), and the nonstandard positioning required during the procedure. Regardless of the medications chosen, adequate monitoring should occur during the procedure as well as during the recovery period. With a good sedation plan for both sedation and analgesia, adequate monitoring, and contingency planning for adverse events, this can safely be performed in institutions with highly motivated and organized sedation services.
Percutaneous Coronary Intervention with Concomitant Atrial Fibrillation
Authors: Woo Joseph W. , Kim Gregory K.
Published: January 2019

Cardiac comorbidities are oftentimes not limited to a single diagnosis, and multiple cardiac abnormalities may have to be considered when administering an appropriate anesthetic. Atrial fibrillation is an abnormal cardiac rhythm with uncoordinated depolarization of the atria causing an irregularly irregular ventricular response. Optimization requires heart rate control as well as anticoagulation, which must be considered prior to any surgical procedure. Percutaneous coronary intervention or coronary stents are placed in the coronary arteries in the face of coronary artery stenosis. The circumstances of when the stents were placed, as well as the type of stents that were used, will determine how long dual antiplatelet therapy must be undertaken and when elective surgery can take place.
Pulmonary Comorbidities in Endoscopic Retrograde Cholangio-Pancreatography Procedure and Ambulatory Anesthesia
Authors: Abdullah Ali R. , Zheng Lu
Published: January 2019

Ambulatory surgery anesthesia is one of the fastest-growing subspecialties in anesthesia. Outpatient procedures cost less in the ambulatory setting than in hospitals and provide increased efficacy and convenience to both the proceduralist and the patient. The most common ambulatory procedure performed includes gastrointestinal procedures, performed under either general anesthesia or, more often, monitored anesthesia care. Although usually less complicated than most inpatient surgeries, anesthetic management in ambulatory surgery settings can be challenging and requires equal anesthesia expertise to be performed efficiently without compromising safety. This chapter uses the case study of a 63-year-old woman noticed to have jaundice and intermittent right upper quadrant abdominal pain since around 6 weeks ago who is scheduled to have an endoscopic retrograde cholangiopancreatography at the gastrointestinal suite of a tertiary medical center.
Waking up My Outpatient, Who Looks to Now be Seizing
Authors: Cruz Miguel A.
Published: January 2019

The postanesthesia care unit is a highly intense area where patients recover as they emerge from anesthesia and surgery. Multiple perioperative problems can occur, and physicians and nurses must be vigilant and be available to tackle problems that arise. Outpatient anesthesia is currently an area of great demand. Surgeons and patients seek safe procedures associated with minimal complications and discharge to home on the same day. Many times these patients may not be properly worked up and could have allergies, intolerances, and comorbidities. This case describes unexpected seizure in the postanesthesia care unit and discusses its diagnostic dilemmas and management.
Myasthenia Gravis Patient Presenting for Ureteroscopy
Authors: Barnes Theresa J. , Benson Amanda Moraska , Khanna Ashish K.
Published: January 2019

Myasthenia gravis (MG) is an autoimmune condition, most commonly affecting middle-aged women and older males, caused by antibody-mediated attack of the postsynaptic nicotinic acetylcholine receptors at the neuromuscular junction. The resulting skeletal muscle weakness can be highly variable, ranging from fatigue of ocular muscles only to significant respiratory impairment with peripheral muscle weakness. MG has multiple important implications for anesthesiologists. This surgical case explores the pathophysiology of MG, common treatments, preoperative anesthetic assessment, intraoperative considerations, implications for anesthetic drug interactions, predictors of postoperative respiratory insufficiency, and a review of postoperative concerns and complications. Topics covered include myasthenic crisis, postoperative respiratory insufficiency, anticholinesterase, neuromuscular blocking drugs, thymectomy, and extubation criteria.