bluuebunny/crossref_metadata_2025 huggingface dataset:
Perspective Switching in Young and Older Adults
Authors: Martin Andrew , Huang Jasmine , Matuschka Lori , Meinzer Marcus
Published: November 2019

One aspect of visual perspective taking (VPT) is the ability to switch between perspectives associated with self and others. Attenuated inhibition of the egocentric perspective is thought to underlie perspective taking difficulties in older adults leading to impaired social function. 117 adults (50 older adults 55-79 years; 67 young adults 18-36 years) completed two visual perspective taking tasks. The first task measured perspective tracking and required participants to understand what can be seen from the egocentric or allocentric perspective. The second measured perspective taking and required understanding how objects are seen from the egocentric or allocentric perspective. Both tasks involved trials that were congruent or incongruent between the two perspectives in order to assess how the other perspective interferes with the task-relevant perspective. Trials were further separated into those that required switching (preceding perspective was different to current) or sticking (preceding perspective was the same). We show an egocentric switch cost during perspective tracking in younger adults thought to reflect inhibition of the default egocentric perspective in the preceding trial. However, this effect was not identified in older adults. Moreover, older adults showed greater interference from their own perspective when required to stick with the allocentric perspective. No age differences were identified during perspective taking with both age groups showing an egocentric switch cost and an allocentric stick cost. The results provide evidence for age-related changes in VPT that are dependent on the requirement to switch or stick perspectives. Increased egocentricity in older adults is apparent but dependent on the switch-related context.
La compétitivité au centre des luttes entre cultures capitalistes
Authors: Smith Andy
Published: November 2019

En s’appuyant sur les résultats d’enquêtes récentes conduites dans une optique d’économie politique, cet article argumente tout d’abord que les institutions qui encadrent l’activité économique sont beaucoup plus que des règles formelles et des normes informelles. Ces institutions sont également, et surtout, des conventions sociales qui imposent constamment des paramètres forts sur comment les enjeux socio-économiques sont pensés et sur la manière dont on peut agir sur eux. En effet, c’est parce qu’elles façonnent les attentes des acteurs et des populations concernées qu’il est heuristique, voire essentiel, d’analyser les « cultures » capitalistiques, c’est-à-dire les hiérarchies de valeurs qui, dans tel ou tel espace social, impactent lourdement le changement ou la reproduction institutionnelle. Cette thèse centrale est ensuite étayée à travers des exemples empiriques développés d’une part à l’échelle d’une industrie spécifique (l’agro-alimentaire) et, d’autre part, à celle d’une politique économique transversale (la politique de la concurrence européenne).
La mutilation de l’individualisme libéral dans le capitalisme contemporain
Authors: Spitz Jean-Fabien
Published: November 2019

L’hypothèse formulée ici est que le capitalisme contemporain mutile la culture de l’individualisme en l’amputant de l’une de ses deux composantes alors qu’elle doit reposer sur l’équilibre entre deux séries de normes distinctes : des normes multilatérales de justice distributive et des normes bilatérales de justice commutative. Or le néolibéralisme contemporain prétend reléguer les normes de la justice distributive dans le domaine de la moralité privée au nom de l’arbitraire auquel leur mise en œuvre par la puissance publique exposerait les individus. C’est une mutilation, car les transactions bilatérales de la justice commutative ne sont porteuses de valeurs individualistes normativement importantes que si elles prennent place dans un contexte d’arrière-plan distributivement équitable. La seconde hypothèse formulée ici est que, contrairement à l’affirmation selon laquelle le néo libéralisme serait un retour au libéralisme des origines, les fondateurs de ce dernier étaient parfaitement avertis de la nécessité, pour une société de liberté, de réaliser un équilibre entre les deux exigences et que leurs œuvres en portent témoignage.
Le capitaliste sur la scène des spectacles du groupe Octobre à La Folle de Chaillot de Giraudoux
Authors: Guérin Jeanyves
Published: November 2019

À la différence du roman, le théâtre a peiné à représenter l’entreprise capitaliste. Il était plus facile de mettre en scène les industriels et les banquiers dans leur vie familiale. Parmi les rares pièces consacrées à ce sujet, l’on étudie ici d’abord celles jouées par le groupe Octobre dans les années 1930 qui relèvent de l’agit-prop communiste et un chef-d’œuvre du théâtre d’art, La Folle de Chaillot de Jean Giraudoux. Les premières ont eu une postérité autour de 1968.
Donald Trump and Constitutional Law
Authors: Fassassi Idris
Published: November 2019

By its unconventional nature, the Trump Presidency has shaken the American constitutional order and raises unprecedented issues. This paper analyzes the relationship between Donald Trump and constitutional law through three perspectives. The first is the extent to which, quite counterintuitively, Trump’s presidency has vivified and increased the volume of constitutional discourse, through the rediscovery of forgotten constitutional provisions and the development of new theories. The second is the extent to which Donald Trump is actually violating constitutional law. Lastly, the paper analyzes the ways in which Donald Trump has shaped constitutional law, primarily through his judicial nominations.
Les conversations Tocqueville
Authors: Mélonio Françoise
Published: November 2019

La méfiance populaire envers des élites soupçonnées de pousser à une mondialisation dont elles sont le principal bénéficiaire, la crainte devant la montée de la Chine et l’agressivité de la politique étrangère russe avaient conduit à réaffirmer, lors de la première édition des Conversations Tocqueville, la nécessité d’une politique inclusive et du recours au cadre protecteur des nations contre les inégalités extrêmes et les excès de la mondialisation. C’est sur cette question de la nation, de sa nécessité et de sa légitimité problématique que la deuxième édition s’est concentrée les 28–29 juin 2019 au Château de Tocqueville. Les nations sont-elles les cadres adéquats pour combattre la crise des démocraties ? Comment penser les rapports entre États-nations et économie ? Y a-t-il des problèmes que la nation peut résoudre et d’autres que seul le multilatéralisme est apte à traiter ?
The Effects of Capitalism on People, Personality and Culture
Authors: Kahan Alan S. , Marshall Catherine , Nowicki Joanna
Published: November 2019

The 19 essays in this collection present an international and pluridisciplinary approach to the relation between capitalism, personality and culture, from the eighteenth century to the present. In Part I: Capitalism and Social Thought, they look primarily at social and economic thought, and in Part II: Representations of Commerce and Capitalism, they examine film, theatre, music, television, and journalism. By treating perspectives as widely separated as those of Montesqueiu, Marx, Rand, and Wajda, and examining representations from a number of countries and languages, including France, the United States, Poland, Hungary, Italy and the UK, the essays present a contrasting and rapidly shifting portrait of the meaning of some of the most contested terms in our present-day politics and society.
« Rédempteur du peuple » ou « infernale exploitation »? le crédit, la dette et l’usurier dans la France du XIXe siècle
Authors: Rabault-Mazières Isabelle
Published: November 2019

L’objet de cet article est d’examiner les représentations du crédit, de la dette et de l’usurier dans la France du XIXe siècle. Alors que le crédit est essentiel au fonctionnement économique et social, et que la modernisation politique et économique entraîne un développement et une institutionnalisation des pratiques de crédit, l’imaginaire collectif apparaît tiraillé entre des représentations contradictoires. À partir de sources variées, nous montrons que derrière les images nouvelles associées au crédit dans la première moitié du siècle, fortement positives, les représentations d’un endettement mortifère et de la figure malfaisante de l’usurier persistent. L’essor du crédit populaire associé à une valorisation nouvelle du crédit à la fin du siècle n’estompe pas, au début du XXe siècle, ces images héritées.
A Tale of Two Capitalisms
Authors: Den Uyl Douglas J.
Published: November 2019

In this paper I compare Adam Smith and Ayn Rand on their respective understandings of capitalism. The paper begins by describing the “myth” that surrounds each of these thinker’s depiction of capitalism followed by a discussion of how accurately those myths accord with the texts of these two thinkers. In the case of Smith I argue that the myth is somewhat wide of the mark, but in Rand’s case much closer. It would appear, therefore, that we have two quite different understandings of the nature of capitalism. I conclude, however, by arguing that we may have only one capitalism with a focus on two different aspects of it, which are not necessarily in contradiction though those aspects may indeed be in tension. I end by suggesting that what may be keeping the tension from breaking apart is entrepreneurship.
Writing Instruction, Academic Labour, and Professional Development
Authors: Darroch Heidi , Maftei Micaela , Humphreys Sara
Published: November 2019

As we envisioned this special section and, in turn, encouraged colleagues to contribute, we confronted one of the ironies of post-secondary writing instruction: many of the people entrusted with the responsibility of supporting student writing development are, essentially, excluded from professional conversations about effective writing pedagogy. That is, hired term-by-term, treated by their departments as fungible, and burdened with excessive teaching loads, university writing instructors may lack a sense of belonging to a profession or a discipline. College instructors, in turn, are also frequently precarious; even if working in full-time and permanent positions, they have little opportunity to engage with the profession, conducting research, as Brenna Clarke Gray points out, “off the sides of our desk.” The effect is a feeling of isolation and, for too many, despair about the sustainability of their work in higher education. This sentiment is expressed in the excellent work submitted by our contributors, who are each at differing points on their professional timelines, and, as a result, provide a range of viewpoints. We are grateful for their provocative and engaging work, and we also appreciate and acknowledge the formidable challenges of potential contributors who explained why they could not produce articles for publication--including some who struggled with how to represent their experience of academic precarity without hampering their employment prospects. We thank the editors of CJSDW/R for their patience and assistance as we completed this project amid other responsibilities.
Kambin’s triangle: definition and new classification schema
Authors: Fanous Andrew A. , Tumialán Luis M. , Wang Michael Y.
Published: November 2019

Kambin’s triangle is an anatomical corridor used to access critical structures in a variety of spinal procedures. It is considered a safe space because it is devoid of vascular and neural structures of importance. Nonetheless, there is currently significant variation in the literature regarding the exact dimensions and anatomical borders of Kambin’s triangle. This confusion was originally caused by leaving the superior articular process (SAP) unassigned in the description of the working triangle, despite Kambin identifying that structure in his original report. The SAP is the most relevant structure to consider when accessing the transforaminal corridor. Leaving the SAP unassigned has led to an open-handed application of the term “Kambin’s triangle.” That single eponym currently has two potential meanings, one meaning for endoscopic surgeons working through a corridor in the intact spine and a second meaning for surgeons accessing the disc space after a complete or partial facetectomy. Nevertheless, an anatomical corridor should have one consistent definition to clearly communicate techniques and use of instrumentation performed through that space. As such, the authors propose a new surgically relevant classification of this corridor. Assigning the SAP a border requires adding another dimension to the triangle, thereby transforming it into a prism. The term “Kambin’s prism” indicates the assignment of a border to all relevant anatomical structures, allowing for a uniform definition of the 3D space. From there, the classification scheme considers the expansion of the corridor and the extent of bone removal, with a particular focus on the SAP.
Using machine learning to predict 30-day readmissions after posterior lumbar fusion: an NSQIP study involving 23,264 patients
Authors: Hopkins Benjamin S. , Yamaguchi Jonathan T. , Garcia Roxanna , Kesavabhotla Kartik , Weiss Hannah , Hsu Wellington K. , Smith Zachary A. , Dahdaleh Nader S.
Published: November 2019

OBJECTIVE

Unplanned preventable hospital readmissions within 30 days are a great burden to patients and the healthcare system. With an estimated $41.3 billion spent yearly, reducing such readmission rates is of the utmost importance. With the widespread adoption of big data and machine learning, clinicians can use these analytical tools to understand these complex relationships and find predictive factors that can be generalized to future patients. The object of this study was to assess the efficacy of a machine learning algorithm in the prediction of 30-day hospital readmission after posterior spinal fusion surgery.

METHODS

The authors analyzed the distribution of National Surgical Quality Improvement Program (NSQIP) posterior lumbar fusions from 2011 to 2016 by using machine learning techniques to create a model predictive of hospital readmissions. A deep neural network was trained using 177 unique input variables. The model was trained and tested using cross-validation, in which the data were randomly partitioned into training (n = 17,448 [75%]) and testing (n = 5816 [25%]) data sets. In training, the 17,448 training cases were fed through a series of 7 layers, each with varying degrees of forward and backward communicating nodes (neurons).

RESULTS

Mean and median positive predictive values were 78.5% and 78.0%, respectively. Mean and median negative predictive values were both 97%, respectively. Mean and median areas under the curve for the model were 0.812 and 0.810, respectively. The five most heavily weighted inputs were (in order of importance) return to the operating room, septic shock, superficial surgical site infection, sepsis, and being on a ventilator for > 48 hours.

CONCLUSIONS

Machine learning and artificial intelligence are powerful tools with the ability to improve understanding of predictive metrics in clinical spine surgery. The authors’ model was able to predict those patients who would not require readmission. Similarly, the majority of predicted readmissions (up to 60%) were predicted by the model while retaining a 0% false-positive rate. Such findings suggest a possible need for reevaluation of the current Hospital Readmissions Reduction Program penalties in spine surgery.
A review: evolution of big data in developing country
Authors: Prasetyo Bayu , Aziz Faiz Syaikhoni , Faqih Kamil , Primadi Wahyu , Herdianto Roni , Febriantoro Wicaksono
Published: November 2019

The development of technology from year to year is increasingly rapid and diverse. All systems that exist in human life began to be designed with technology that requires large data storage. Big Data technology began to be developed to accommodate very large data volumes, rapid data changes, and very varied. Developing countries are starting to use Big Data a lot in developing their systems, such as healthcare, agriculture, building, transportation, and various other fields. In this paper, it explains the development of Big Data applied to the sectors previously mentioned in developing countries and also the challenges faced by developing countries in the process of developing their systems.
The Challenges of using Value-Driven Design for practical design of UAVs
Authors: Surendra Amrith , Ferraro Mario , Schumann Ben , van Schaik Jeroen , Daniels Joshua J. , Gorissen Dirk , Scanlan Jim P. , Keane Andy J.
Published: November 2019

The Decision Environment for Complex Designs (DECODE) project at the University of Southampton aims to provide a multidisciplinary environment to support and improve design decisions in order to maximize long term product value. This approach involves the analysis of the overall product life-cycle, from conceptual design to the end of its service life. This paper discusses the issues faced and the limitations of the DECODE framework in the design, search and optimisation of multiple UAV configurations. The fundamental issue lies in the calculation of value metric, which indicates the ‘goodness’ of the system. The value metric used is based on Net-Present-Value (NPV) where a monetary value is assigned to mission success. In the case of search and rescue operations it is the value of saving a human life. This paper also explores the possible solutions to increase the flexibility of the DECODE design tool. Central to the DECODE design process is the concept design tool which was developed from basic principles and augmented with empirical data coming from previous UAVs designs. This however, limits the assessment of various UAV configurations as the runtime for each configuration is significant which makes the evaluation of multiple UAV systems infeasible. A more rapid assessment methodology is proposed: this involves a Knowledge-based Framework (KBF) that allows the user to explore various UAV configurations and down select from them using requirements. This framework is based on an aircraft domain ontology and logic inference, which utilizes semantic-web-tools and an organized flow of information that ensures clarity in the decisions made.
Defining a research agenda in Value Driven Design: Questions that need to be asked
Authors: Soban Danielle S. , Price Mark A. , Hollingsworth Peter
Published: November 2019

Value driven design is an innovative design process that utilizes the optimization of a system level value function to determine the best possible design. This contrasts with more traditional systems engineering techniques, which rely on satisfying requirements to determine the design solution. While ‘design for value’ is intuitively acceptable, the transformation of value driven design concepts into practical tools and methods for its application is challenging. This, coupled with the growing popularity of value-centric design philosophies, has led to a proposed research agenda in value driven design. This research agenda asks fundamental questions about the design philosophy and attempts to identify areas of significant challenge. The research agenda is meant to stimulate discussion in the field, as well as prompt research that will lead to the development of tools and methodologies that will facilitate the application of value driven design and further the state of the art.
Short-term allocation of Time Windows to flights through a distributed market-based mechanism
Authors: Castelli Lorenzo , Pesenti Raffaele , Ranieri Andrea
Published: November 2019

Air Traffic Flow Management delays are often caused by multiple capacity constrained air traffic resources. In this context, we propose an individual rational and weakly budget balanced market-based negotiation mechanism between flights and the network manager. This mechanism allows flights to pay for reducing their delays or get compensations if they accept an increased delay, with respect to the delay allocated under a First-Planned-First-Served policy. Specifically, we introduce a Lagrangian-based primal distributed heuristic that enables flights to determine the market price of the airspace resources composing their business trajectories. Some computational experience based on a real case instance is reported.
Investigating catastrophic behavior in aerospace design
Authors: Hollingsworth Peter
Published: November 2019

The design of modern aerospace systems is commonly an exercise in creating and working with complex systems. This complexity stems from a combination of the complexity of the system itself, the interaction with environment that it operates in and often the organization which is creating the system. Historically, this complexity has been seen as a source of risk and uncertainty, especially with respect to the future performance and utility of the system. Consequently actions were taken to minimize the downside risk, and especially eliminate what were considered significant failure modes. This risk minimization encompasses both technical and programmatic aspects. As a response the behavior of the program becomes inherently ‘stiff’ and is less likely to evolve to meet changes in the environment. Consequently it may actually be more likely that the program will fail suddenly and late in its development. One possible theory that helps to describe these behaviors and may unlock some of this information is Catastrophe Theory. When combined with a utility approach, specifically a Value-Driven approach this has the option to help organize the concept exploration and decision making phases of design.
Value Operations Methodology (VOM) applied to medium-range passenger airliner design
Authors: Curran R. , Beelearts W. , Abu-Kias T. , Repco M.J.F. , Sprengers Y.L.J. , van der Zwet P.N.C.S.
Published: November 2019

This paper gives insight in the development of a Value Operations Methodology (VOM) that can be used to support Value Driven Design (VDD). The VOM establishes expressions for operational value levers that are incorporated into a weighted value function. This value function is then used to optimize the design variables that are incorporated into it so that the design process is actively driven by value assessments that provide design decision metrics. However, the VOM is generic in nature and has a much wider range of influence to the design process for any engineering product. The methodology is verified by means of a case study, analyzing the value difference between the Boeing 737-200, Boeing 737-800, Embraer ERJ-145 and the Airbus 319 as part of a use-case study. In fact, the fundamental conclusion from the work presented is actually that VDD simply promotes the sustained application of the main utility values that were originally recognised but which, due to the complexity of the product and enterprise, tends to be disaggregated into isolated requirements. Ultimately, this leads to optimisation at a sub-system level and that is especially unacceptable for a complex system (with many sub-systems), whereas the re-focus of VOM helps to significantly shift the design effort back to creatively solving the main goal, rather than simply and somewhat robotically making sure the requirements are satisfied. The verification and validation work presented is recognised as indicative but the authors believe that it is extremely significant in pointing towards the potential gains from sustaining a more holistic appraisal and approach through-out the design process. Notwithstanding, the key message of the paper is the need for value modelling within engineering so that we are in control of the consequences of what we are actualising, where value is realised through operational delivery and excellence. This paper has presented a broad methodology in opening up a significantly different approach to aircraft design that is both performance and economics driven while also incorporating other crucial drivers of a much more holistic nature, proactively rather than reactively.
Air traffic complexity in future Air Traffic Management systems
Authors: Prandini Maria , Putta Vamsi , Hu Jianghai
Published: November 2019

In this paper we study the issue of characterizing the complexity of air traffic to support Air Traffic Management (ATM) operations. We discuss, in particular, the features of a complexity metric that are relevant for application to future ATM systems where part of the responsibility for separation assurance and trajectory management operations is distributed on board of the aircraft. We then describe a probabilistic complexity metric that meets all those features and is amenable for supporting onboard conflict detection and resolution and trajectory management operations. A numerical example illustrates its possible use in a fully automated self-separation context.
Asymptotic expansion for the optimal cost of an ill-posed problem with singular perturbations
Authors: Bertrand Pierre
Published: November 2019

We give the development of jε: the optimal cost of the nonlinear problem with singular perturbations with state equation

−εz″(t)−f(z(t))=υ and z(0)=z(T)=0

and with cost

Jε(υ,z)= $\frac{1}{2r}$ ‖z−zd‖2rL2r(0,T)+½N‖υ‖2L2(0,T).

We make a formal expansion of the optimality system. In the case without constraints, we introduce boundary layer terms to approximate it to order 0(εk) for any k>0. We show that the boundary layer terms decay exponentially. We deduce, from the approximate optimality system, the expansion of jε, to order O(ε2k) and the associated control.
Diffusion approximation of the linear semiconductor Boltzmann equation: analysis of boundary layers
Authors: Poupaud F.
Published: November 2019

This paper deals with mathematical properties of the semiconductor Boltzmann equation. We first investigate the question of existence of solutions and some basic properties of the collision operator. Then we study the connection with the drift diffusion model by using a perturbation approach, the so-called diffusion approximation.

For justifying rigorously this theory, we have to deal with boundary layers. A half space problem (Milne problem) arises in the study of the boundary corrector. We prove existence and we give the asymptotic behaviour of its solutions.
G-convergence and semilinear elliptic equations
Authors: Dall'Aglio A. , Tchou N.A.
Published: November 2019

We study the behavior of positive solutions of semilinear elliptic equations −div(aε(x)Duε=g(uε) with homogeneous Dirichlet boundary data, with respect to the G-convergence of the elliptic matrices aε. Here the function g has a subcritical or critical growth with respect to Sobolev imbedding.
Spectral asymptotics for Hill's equation near the potential maximum
Authors: März Christoph
Published: November 2019

We study the spectrum of a one-dimensional semiclassical periodic Schrödinger operator near the potential maximum. The potential is supposed to be analytic and to have only one point of maximum over the period, which in addition is assumed to be non-degenerate. The spectrum is the union of bands, and some energy value is belonging to the spectrum, if and only if the trace of the operator of translation by the period acting on the two-dimensional space of solutions of the corresponding stationary Schrödinger equation lies in [−2,2].

By application of a result by Helffer and Sjöstrand we can take the dilation generator as a model near the potential maximum, and by application of a Fourier integral operator we find local solutions that have a standard WKB-form away from the point of maximum. So we may extend them over the whole period in order to compute the asymptotics of the trace of the translation matrix such that we finally obtain the size of the bands and the gaps separating them.
Correctors results for relaxed Dirichlet problems
Authors: Finzi Vita Stefano , Tchou Nicoletta Anna
Published: November 2019

We consider the asymptotic behaviour of the solutions of a sequence of elliptic problems with homogeneous Dirichlet boundary conditions, involving singular potentials which can be Borel measures with infinite values. Problems of this kind, introduced in (Dal Maso and Mosco, 1986) and (Dal Maso and Mosco, 1987) are called ‘relaxed Dirichlet problems’ since they form the smallest family of equations, stable under the convergence of solutions in L2, which includes Dirichlet problems with zero boundary conditions on many small holes (see also (Cionarescu and Murat, 1982) and (Dal Maso, 1987)).

After extraction of a subsequence, the solutions converge weakly in H10(Ω) to the solution of a limit problem of the same type. We determine a corrector, i.e. an explicit expression constructed from the limit of the solutions and from some generalized capacitary potentials, the difference of which with the solution tends strongly to zero in H10(Ω). Under suitable regularity assumptions on the limit problem, we are able to prove a strong convergence results and an abstract error estimate. Moreover, we prove in the general case that there is no need of correctors in the singular set of the measure of the limit problem.
Overall behavior of elastic plates with periodically distributed fissures
Authors: Chacha D. , Sanchez-Palencia E.
Published: November 2019

We consider the macroscopic behavior of an elastic plate containing many small fissures distributed periodically, the period being of the same order as the thickness of the plate. In the fissures a one-side constraint of the Signorini's kind is prescribed. The macroscopic behavior involves a nonlinear monotone strain-stress law, and coupling of tensions and flexions.
Asymptotic implicit function theorems
Authors: Gérard R. , Jurkat W.B.
Published: November 2019

In this paper we are extending the classical preparation theorem and division theorem to an asymptotic case.
A free boundary problem arising in superconductor modeling
Authors: Friedman Avner , Hu Bei
Published: November 2019

By gradually decreasing the ambient magnetic field, under isothermal conditions, a superconductor material (of “type I”) will develop two phases separated by a thin interface Γ(t). In the “normal” conducting phase the magnetic field $\vec{H}$ is divergence free and satisfies the heat equation, whereas on the interface Γ(t), curl $\vec{H}\times n=-V_{n}\vec{H}$ where n is the normal and Vn the velocity of Γ(t); further, $|\vec{H}|=H_{c}$ (constant) on Γ(t). This free boundary problem is studied in the present paper. Existence, uniqueness and asymptotic behavior are established under assumptions which enable us to reduce the 3-dimensional problem to a problem depending on essentially one-dimensional space variable.
A boundary value problem of mixed type on perforated domains
Authors: Figari R. , Teta A.
Published: November 2019

We analyze a boundary value problem of mixed type with data prescribed on the union of m spheres of small (order m−1) radius. We establish the connection to a particular class of zero-range perturbations of the Laplacian and exploit it for the asymptotic (m→∞) analysis of the solution. It is shown that in the limit problem the “density of scattering length” enters as an effective potential.
Limiting behaviour of a spectral problem in fluid-solid structures
Authors: Conca C. , Planchard J. , Vanninathan M.
Published: November 2019

The aim of this paper is the asymptotic analysis of a spectral problem which involves Helmholtz' equation coupled with a nonlocal Neumann boundary condition on the boundary of a periodic perforated domain of R2. This eigenvalue problem represents the vibrations (eigenfrequencies and eigenmotions) of a tube-bundle immersed in a perfect compressible fluid. Our analysis of convergence shows that the vibrations of this fluid–solid structure with a large number of tubes are close to the spectrum of an unbounded operator in a Hilbert space. Using the method of Bloch and exploiting the periodic structure of the problem, we derive the spectral family of this limit operator and we prove that its spectrum can be completely determined by only computing local eigenvalue problems in the basic cell representing the periodic structure in the problem.
Weyl asymptotic of the scattering phase for metric perturbations
Authors: Petkov Vesselin
Published: November 2019

We examine the scattering phase related to metric perturbations of the Laplacian and we obtain a Weyl type formula with oscillating term related to absolutely periodic trajectories.
HUM and the wave equation with variable coefficients
Authors: Miranda Manuel Milla
Published: November 2019

This paper is concerned with the boundary exact controllability for the equation: [Formula: see text] where Q is a finite cylinder Ω×]0,T[, Q a bounded domain of Rn. The result is obtained by the HUM which was introduced by J.L. Lions. The above equation appears in the study of boundary exact controllability for the wave equation in non-cylindrical domains.
Travelling waves in shallow water
Authors: Frank L.S.
Published: November 2019

Quasi-stationary surface water waves propagating along a distinguished space direction in an infinite channel of finite depth are considered under the assumption that the liquid is inviscid irrotational and incompressible. Besides the gravitation effect also the capillary phenomenon is taken into consideration. After rescaling the mathematical problem is reduced to a singularly perturbed pseudodifferential equation on the free boundary of the liquid. Depending on the values of two basic dimensionless parameters, the rescaled speed of propagation and the parameter characterizing the surface tension (capillarity), the existence of different kind of quasi-stationary waves (periodic, solitary and their superposition) is established for this exact mathematical model and their asymptotic behavior is investigated when the natural dimensionless small parameter (the ratio of the depth of the undisturbed liquid's layer and the wave's length scale) vanishes.
Critical points of the Ginzburg–Landau system on a Riemannian surface
Authors: Baraket Sami
Published: November 2019

We study here the Ginzburg-Landau functional on a Riemannian surface S endowed with an arbitrary metric

Eε(u)=½∫𝒮||∇u||2+1/(4ε2)∫𝒮(|u|2−1)2, u∈H1(S,C),

where ε∈]0,+∞[. We study the asymptotic behaviour of the critical points for Eε as ε→0. We define a renormalized energy which allows to characterize the position of the singularities at the limit.
Asymptotic analysis of the linearized Navier–Stokes equations in a general 2D domain
Authors: Temam Roger , Wang Xiaoming
Published: November 2019

We continue our study of the asymptotic behavior of the Navier–Stokes equations linearized around the rest state as viscostiy ε approaches zero. We study the convergence as ε→0 to the inviscid type equations. Suitable correctors are obtained which resolve the boundary layer and we obtain convergence results valid up to the boundary. Explicit asymptotic expansion formulas are given which display the boundary layer phenomena. We improve our previous by treating here the general smooth bounded domain in R2 instead of two-dimensional channels. Curvilinear coordinates are used to resolve the complex geometry.
The propagation of the waves in periodic media at large time
Authors: Korotyaev Evgeni
Published: November 2019

Asymptotic estimates at large time of the Green function to the wave equation with periodic coefficients are found. An estimate of the wave front is also obtained. It is shown that the spectral band (with number n=0,1,2,…) of the corresponding Hill operator ‘creates’ a wave having the front velocity cn < 1 . Estimates of cn in the terms of the gap lengths, the effective masses of the Hill operator are proved, both with fixed number n and their sums. Some extensions for more general cases (the Dirac operator with periodic coefficients, the Schrodinger operator with finite band potentials etc.) are also obtained.
PENGARUH STRATEGI HARGA DAN KUALITAS PELAYANAN TERHADAP KEPUTUSAN PEMBELIAN TIKET MASKAPAI PENERBANGAN CITILINK DI BANDARA SOETA JAKARTA
Authors: Harras Hadyati
Published: November 2019

ABSTRAKTujuan daripenelitian ini adalah untukmengetahui pengaruh strategi harga dan kualitas pelayanan terhadap keputusan pembelian tiket maskapai penerbangan Citilink di Bandara Soeta Jakarta.Desain penelitianyang digunakandalam penyusunan penelitian ini adalah kuantitatifasosiatif kausal dengan eksplanasi (penjelasan) deskriptif. Adapun metode analisis yang digunakan adalah analisis regresi linear berganda dengan sampel sebanyak 98 dan teknik sampling yang digunakan adalah teknik Accidental Sampling.Hasiluji hipotesis berdasarkan pengujian regresi linear menunjukkan bahwaharga terbukti berpengaruh positif dan signifikan terhadap keputusan pembelian sebesar 0.510 dan t hitung  5.484. Sedangkan kualitas pelayanan berpengaruh positif dan signifikan terhadap keputusan pembelian sebesar 0.258 dan t hitung 2.768. Hasil analisis regresi membuktikan terdapat pengaruh secara simultan variabel strategi harga dan kualitas pelayanan secara bersama-sama terbukti berpengaruh positif dan signifikan terhadap keputusan pembelian dengan kontribusi sebesar 47,7%sedangkan sisanya sebesar 52,3% dijelaskan oleh variabel lain di luar penelitian ini. Kata Kunci : Strategi Harga, Kualitas Pelayanan, Keputusan Pembelian.
反季节种植在园林绿化施工中的应用
Authors: 张 中院
Published: November 2019

本篇文章首先对反季节种植的重要性进行阐述,从场地选择、种植时间两个方面,对反季节种植在园林绿化施工中的应用要求进行解析,并以此为依据,提出反季节种植在园林绿化施工中的应用对策。
环境监测工作中悬浮物检测的准确性研究
Authors: 刘 金冠
Published: November 2019

随着我国社会经济持续稳定的发展,虽然工业化事业取得了良好成效,但对水体污染也造成了严重影响。再加上水土流失问题一直得不到有效控制,导致水体中悬浮物不断增加,如果得不到及时处理,就会降低水体的透明度,影响水体中生物的代谢。本文针对环境监测工作中悬浮物检测相关内容,通过分析影响悬浮物监测准确性的主要因素,提出相应的控制措施。开展悬浮物检测,将获得的检测结果,作为环境治理与保护依据,因此要做好检测精准度的控制。
基于PSR模型的四川省土地生态安全评价
Authors: 陈 敏
Published: November 2019

笔者基于四川省21个地市州,采用PSR(压力-状态-响应)模型的方法,构建土地生态安全评价的指标体系,利用指数法、ArcGIS软件对2014至2018年四川省的土地生态安全进行评价。
浅谈绥中干旱成因及防御
Authors: 钟 志勇 , 刘 辉
Published: November 2019

干旱是绥中主要气象灾害之一,以播种期、水分临界期、作物需水关键期的影响最大,造成出苗不全不齐不壮,影响受精过程、灌浆过程等。通过大气环流因素影响、气候条件因素和环境因素分析干旱成因,提出有效的防御措施。
Bone Status in Patients with Sickle Cell Disease:
Authors: El Deek Bassem S.
Published: November 2019

Objectives (background): Both sickle cell disease and vitamin D deficiency are common among Saudi population. The present work asses Parathyroid hormone/Vitamin D axis as well as bone dynamics in young Saudi adults with sickle cell disease.

Methods: A case-control study includes forty patients known to have sickle cell disease from the outpatient clinics of North Western Armed Forces Hospital, Tabuk were randomly selected for the study. Another 120 healthy individuals were involved as control. Cases and control were subjected to full history taking, clinical examination, and radiologic and laboratory investigations.

Results: Bone image revealed diffuse osteopenia in 16 (40%) of the cases, avascular necrosis of the femoral head in 6 (15%), code fish vertebral bodies in 6 (15%) and coarse trabecular pattern in 6 (15%). Laboratory investigations for patients revealed hypocalcemia in 18 (45%), secondary hyperparathyroidism in 24 (60%), non-detectable vitamin D in 30 (75%) and detectable but subnormal vitamin D in 10 (25%). The mean level for serum calcium in cases was significantly less than that for the control (p < 0.001). The mean level for serum intact parathyroid hormone was significantly higher in the patients than the control (p < 0.001). The mean serum level for the Serum 25-hydroxyvitamin was significantly lower in the studied cases than the control. For the serum bone, specific alkaline phosphatase the mean level was significantly higher in case than control (p < 0.001).

Conclusion: Vitamin D deficiency through a common finding it is more severe in patients with sickle cell disease with subsequent secondary hyperparathyroidism and frequent hypocalcemia.
Knowledge of Pulmonary Tuberculosis in the Saudi Community in Jeddah
Authors: Wali Siraj O. , Samargandi Osama A. , Abulaban Ahmad A. , El Deek Bassem S. , Mirdad Lujain H.
Published: November 2019

Background: Pulmonary tuberculosis is a common and current health problem in Saudi Arabia. Public education and awareness are essential for the prevention of tuberculosis. This study aims at assessing the level of knowledge among people in Jeddah regarding this re-emerging disease.

Methods: A cross-sectional, self-administrated questionnaire-based study was conducted at three main shopping centers in Jeddah city, after pilot study testing. A structured questionnaire was developed to assess the basic knowledge about pulmonary tuberculosis which included demographic data, level of education, source and level of knowledge (basic facts) about pulmonary tuberculosis.

Results: The questionnaire was completed by 436 recruited subjects; 256 (58.7%) females, age ranged between 12 and 72 (mean 28.54 years; SD ± 11.2); 165 (38.9%) were students and 154 (36.3%) were employees. The majority (73%) of candidates were relatively well educated or completed high school. 53.3% of the candidates assumed had sufficient knowledge regarding tuberculosis. 36% were unaware that lungs were the primary organ affected, over half (50.9%) denied it is an infectious disease, and almost half (47.4%) were unaware of effective treatment. The mean score of the level of knowledge for the whole group was 5.20 out of 11 (SD Â± 2.95); 39% scored less than 4. Females scored better than males, 5.55 and 4.69 out of 11, respectively with a p-value of 0.003.

Conclusion: The data showed that public awareness regarding pulmonary tuberculosis was below expectation. Essential information about the disease was lacking even among well-educated people, though female were found to be knowledgeable compared to males.
Intractable Seizures Caused by a Rare Treatable Condition
Authors: Algahtani Hussein A. , Batarfi Abdulaziz H. , Dd Sheikh A. , Lingawi Sattam S.
Published: November 2019

A case of a young man who presented with generalized tonic clonic seizures and intracranial calcification due to primary hypoparathyroidism was reported. He was diagnosed with primary generalized epilepsy for many years in a periphery hospital. His seizures were intractable despite treatment with three antiepileptic drugs. Further evaluation in our center revealed low calcium level, high phosphate, low parathyroid hormone and cerebral calcification on computed tomography imaging. Diagnosis of primary hypoparathyroidism was established and treatment started. He responded well to treatment and currently he has been seizure-free for eight years.
Irreversible Methotrexate Induced Luckencephalopathy Presenting as Recurrent Stroke like Episodes:
Authors: Alnajashi Hind A.
Published: November 2019

A case of young female with leukemia on multiple chemotherapeutic agents including intrathecal methotrexate developed an attack of transient neurological deficit that improved spontaneously, followed by a second attack that was irreversible. MRI finding showed multiple area of increased signal intensity compatible with cytotoxic edema. These finding was suggestive of methotrexate induce toxic leukoencephalopathy. A critical decision was needed regarding discontinuing methotrexate from the chemotherapy protocol. The case is followed by a brief review about methotrexate induced leukoencephalopathy and the best way of its early detection and prevention.
Tongue Squamous Cell Carcinoma in a Young Patient Free of Risk Factors:
Authors: Abulaban Abdulrhman A. , Khoja Lujain A. , Baghlaf Sara S. , Aldahlawi Moataz M. , Al-Ahwal Mahmoud S.
Published: November 2019

Tongue squamous cell carcinoma progresses from an oral premalignant lesion to invasive squamous cell carcinoma. The incidence of tongue carcinoma has been increasing markedly even in patients free of risk factors as the reporting case of a 22-years-old female complaining of small tender whitish discoloration over the left side of the tongue. First, there was a dilemma in the diagnosis taking in consideration that she is young and free of risk factor, but the magnetic resonance imaging of the head and neck showed a heterogenous mass in the tongue with deep muscular invasion. After the result of positron emission tomography-computed tomography, the patient underwent left hemiglossectomy with left supraomohyoid neck dissection and histopathology report showed invasive squamous cell carcinoma. Thus, she was referred for adjuvant radiotherapy. At this point, it emphasized that early recognition is essential; as an extensive history should be obtained from the patient that includes the symptoms emerged and risk factors.
Determinants of Intensive Care Unit Transfer in Patients Admitted to the Medical Ward of an Academic Hospital in Jeddah
Authors: AlAma Mohamed N. , Alghalayini Kamal W. , Alhejily Wesam A. , Abdulwahab Mohammed , Fallatah Hind I. , Jawa Hani A. , Qari Yousef A. , Bazarah Salem M. , Al Johaney Ahmed A. , Wali Siraj O. , Sanosi Ayman K. , Alshareef Aisha A. , Ayoub Omar A. , Alshehri Abdulraheem M. , Almekhlafi Mohammed A. , Alkhayyat Shadi S. , AbuSanad Atlal M. , Al Beladi Fatma I. , Fathalddin Omar A. , Alhozali Amani M. , Mosli Hala H. , Ghamri Khould A. , Binhasher Nawal N. , Alhozali Hanadi , Nabalawi Rana A. , Basheikh Mohammed A. , Al Aama Tareef Y. , Al Zaben Faten N. , Alsulami Fahad , AlKaaki Aroub A. , Jali Ibtisam M. , Bajunaid Nisreen F. , Bahlas Sami M.
Published: November 2019

Objective:  This study aimed to identify the proportion of patients who had clinical deterioration in the medical ward that required intensive care unit transfer and the factors associated with this transfer.

Methods:  A retrospective study of all patients admitted to the medical wards of King Abdulaziz University Hospital between 2010 and 2013 was performed.  The demographics, admitting department, diagnosis at the time of admission to the ward, and cause of intensive care unit transfer were collected.  Patients at risk for deterioration and early intensive care unit transfer were identified using physiologic threshold criteria.

Results:  A screening of 38,380 patients admitted to the various medical services during the study period was performed.  Of these, 356 (0.9%) required intensive care unit transfer.  Most patients were initially admitted from the emergency department (66.3%), while transfers from another hospital comprised approximately 1%.  Intensive care unit transfer patients were more likely to have ischemic heart disease (P < 0.001), diabetes (P < 0.001), renal failure (P < 0.001), or sepsis associated with pressure ulcers (P < 0.001). They were also more likely to be bedridden (P < 0.001) or initially ventilated in the medical ward (P < 0.001).  The mortality rate of the patients was 3.9% with patients who died being more likely to have unstable blood pressure at the time of admission (P = 0.026).

Conclusion: This study identified several factors that were associated with intensive care unit transfer.  Clinicians should consider these factors when determining patient disposition to ensure timely and appropriate management.
Effects of Combined Administration of Nicotine and Caffeine on Adult Rat Prostate
Authors: Rajeh Nesreen A. , Bashykh Bodour M.
Published: November 2019

Objectives: Nicotine and caffeine have been shown to be a reproductive toxicant in animals and are associated with risk of cancer. The objective of this study was to evaluate the combined effect of these two drugs on rat prostate histology and serum testosterone level.

Settings: King Fahad Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.

Design: Experimental study, animals were injected with 100 mg/kg bw of caffeine by intra peritoneal injection daily for one month, concomitantly nicotine was injected at 10 mg/kg bw three times /week by subcutaneous injection. Effect on rats' body weight, histological changes in the prostate, and on serum testosterone level were observed.

Results: Nicotine at the tested dose causes increased interacinar space with reduction in stromal tissue (loose stroma), and also many congested blood vessels were noted in the stroma. The acini themselves become dilated and thin-walled with poorly infolded mucosa and reduction in the height of epithelial lining with flattened columnar cells. An increase in testosterone level was also noted with both the group treated with caffeine alone and with the group treated with both drugs with no significant effect on alanine transaminase or cholesterol.

Conclusion: At the used dose, nicotine caused toxic effects in male rat prostate that can be antagonized by concomitant treatment with caffeine.