bluuebunny/crossref_metadata_2025 huggingface dataset:
Statistical Power for Postlicensure Medical Product Safety Data Mining
Authors: Maro Judith C. , Nguyen Michael D. , Dashevsky Inna , Baker Meghan A. , Kulldorff Martin
Published: December 2017

Objective: To perform sample size calculations when using tree-based scan
statistics in longitudinal observational databases.Methods: Tree-based scan statistics
enable data mining on epidemiologic datasets where thousands of disease outcomes are
organized into hierarchical tree structures with automatic adjustment for multiple
testing. We show how to evaluate the statistical power of the unconditional and
conditional Poisson versions. The null hypothesis is that there is no increase in the
risk for any of the outcomes. The alternative is that one or more outcomes have an
excess risk. We varied the excess risk, total sample size, frequency of the underlying
event rate, and the level of across-the-board health care utilization. We also
quantified the reduction in statistical power resulting from specifying a risk window
that was too long or too short.Results: For 500,000 exposed people, we had at least 98
percent power to detect an excess risk of 1 event per 10,000 exposed for all outcomes.
In the presence of potential temporal confounding due to across-the-board elevations of
health care utilization in the risk window, the conditional tree-based scan statistic
controlled type I error well, while the unconditional version did not.Discussion: Data
mining analyses using tree-based scan statistics expand the pharmacovigilance toolbox,
ensuring adequate monitoring of thousands of outcomes of interest while controlling for
multiple hypothesis testing. These power evaluations enable investigators to design and
optimize implementation of retrospective data mining analyses.
Autopolyploids in fodder grass breeding: induction and field performance
Authors: Dabkevičienė Giedrė , Kemešytė Vilma , Statkevičiūtė Gražina , Lemežienė Nijolė , Brazauskas Gintaras
Published: December 2017

Doubling of chromosome set directly affects plant performance through increase of organ size, higher feeding value and increased resistance to adverse environmental factors. Therefore efficient methods of polyploid induction are needed in order to develop new varieties of naturally diploid fodder grass species. The efficiency of antimitotic agents as colchicine, amiprophos-methyl, trifluralin and oryzalin was compared in a series of tetraploid induction experiments in Lolium multiflorum, L. perenne and Festuca pratensis, while newly developed tetraploid plants were compared to standard tetraploid varieties in the field trials. Colchicine treatment proved to be the most efficient method for in vitro cultured embryos in comparison with the other agents. Induced tetraploids of F. pratensis produced higher dry matter and seed yield and could be used for the development of new varieties. Induced tetraploid plants of Lolium spp. were equal to the standard varieties in field trials, therefore they could be used as parental genotypes in crosses. Induced tetraploids of F. pratensis produced higher dry matter and seed yield and could be used for development of new variety.
Multiclass patent document classification
Authors: Anne Chaitanya , Mishra Avdesh , Hoque Md Tamjidul , Tu Shengru
Published: December 2017

Text classification is used in information extraction and retrieval from a given text, and text classification has been considered as an important step to manage a vast number of records given in digital form that is far-reaching and expanding. This article addresses patent document classification problem into fifteen different categories or classes, where some classes overlap with each other for practical reasons. For the development of the classification model using machine learning techniques, useful features have been extracted from the given documents. The features are used to classify patent document as well as to generate useful tag-words. The overall objective of this work is to systematize NASA’s patent management, by developing a set of automated tools that can assist NASA to manage and market its portfolio of intellectual properties (IP), and to enable easier discovery of relevant IP by users. We have identified an array of methods that can be applied such as k-Nearest Neighbors (kNN), two variations of the Support Vector Machine (SVM) algorithms, and two tree based classification algorithms: Random Forest and J48. The major research steps in this paper consist of filtering techniques for variable selection, information gain and feature correlation analysis, and training and testing potential models using effective classifiers. Further, the obstacles associated with the imbalanced data were mitigated by adding pseudo-synthetic data wherever appropriate, which resulted in a superior SVM classifier based model.
Updated National Comprehensive Cancer Network guidelines for treatment of head and neck cancers 2010-2017
Authors: Wierzbicka Małgorzata , Napierała Joanna
Published: December 2017

Introduction: The diagnostic and therapeutic recommendations have been changing over the years to improve treatment
outcomes and quality of life of Head and Neck Cancer (HNC) patients.
Aim: The aim of this study was to present currently recommended Head and Neck Cancer treatment guidelines based
on the literature review with particular emphasis on novel approaches the NCCN algorithms.
Material and methods: The review of literature covering articles published in the last five years and pointing out essential
changes in HNC treatment regarding evidence based medicine. The study focused on the analysis of novel approaches
for the particular primaries, the implementation of biological therapies and personalized cancer therapies.
Results: Updates in the oncological NCCN guidelines for all ENT primaries except major salivary glands and subglottis
are based on knowledge derived from the basic sciences, clinical trials and the best evidence available currently.
The latest recommendations emphasize value of biological therapies use.
Effect of speechreading in presbycusis: Do we have a third ear?
Authors: Reis Luis Roque , Escada Pedro
Published: December 2017

Introduction: Evidence regarding the effect of speechreading is lacking in age-related hearing loss (presbycusis).
Thus, in individuals with presbycusis, this study determined whether speechreading would improve word intelligibility.
Moreover, the study investigated the effect of speechreading on word intelligibility depending on hearing impairment
severity.
Materials and methods: This analytical, cross-sectional study involved two groups of individuals aged > 65 years
that were enrolled by convenience sampling: 29 individuals with bilateral sensorineural hearing loss compatible with
presbycusis (n=58 ears; mean age, 74.1±9.4 years) and 10 controls with at-most-mild hearing loss (n=58 ears; mean
age, 73.8±8.5 years). All participants underwent a comprehensive medical and audiological evaluation, which included
speech audiometry with and without observation of the audiologist’s face, i.e. speechreading. Within each group,
the effect of speechreading was determined as a change in the speech reception threshold. For all statistical analyses,
p < 0.05 was considered significant.
Results: Both in individuals with presbycusis and controls, speechreading significantly improved speech discrimination
(p<.001<.05); however, compared to controls, this effect of speechreading on speech discrimination was more
pronounced in individuals with presbycusis (p<.001).
Discussion: Individuals with presbycusis or hearing impairment displayed improved spoken-word intelligibility when
spoken-word recognition was coupled with speechreading. Thus, speechreading may serve as a “third ear”.
Représentations sociales de la réussite scolaire dans un pays dit en voie de développement : le cas du Gabon1
Authors: Immongault Marthe Christine , Lapointe Claire
Published: December 2017

Cet article a pour but de présenter une partie des résultats d’une recherche portant sur les représentations sociales de la réussite scolaire dans un pays diten voie de développement. Une étude de cas a été menée au Gabon auprès de lycéens, d’enseignants et de parents vivant en milieux urbain et rural. Fondées sur la théorie des représentations sociales de Moscovici ainsi que sur la typologie de Rivière, Sauvé et Jacques (1997, 2002), des entrevues semi-dirigées ont été réalisées auprès de 23 élèves, 19 enseignants et 19 parents. Les données, analysées à l’aide du logicielAlceste, ont permis de montrer la diversité des représentations sociales de la réussite scolaire au Gabon en fonction du rôle social (élève, enseignant, parent), du genre, du milieu géographique et des résultats scolaires. Les résultats mettent aussi en lumière une certaine confrontation entre ces représentations sociales, selon que la réussite scolaire est vue comme une condition pour la réussite financière, professionnelle, sociale ou personnelle.
Quelles évolutions de l’école française face à l’éducation au patrimoine?
Authors: Barthes Angela , Blanc-Maximin Sylviane
Published: December 2017

Au cours des deux dernières décennies, l’école française connaît plusieurs évolutions dont celles liées à l’émergence des éducations à. Notre analyse porte sur les modalités d’évolution de la forme scolaire vues à travers des études de cas d’éducation au patrimoine local dans les écoles primaires publiques françaises. La méthodologie comprend une analyse diachronique effectuée par questionnaires avant et après les projets sur un échantillon de 90 élèves âgés de 10 à 12 ans répartis dans cinq écoles du sud-est de la France. Elle est complétée par des entretiens qui identifient le sens accordé par les enseignants à cette éducation au patrimoine et par l’étude du discours des concepteurs des projets pédagogiques. Une analyse des travaux d’élèves permet le repérage des savoirs et capacités des élèves préalables et acquis. Les résultats montrent la présence de savoir-faire, de savoirs locaux, mais peu de liens créés avec les savoirs scolaires et une absence de réflexion critique sur la notion de patrimoine. Ils alimentent une réflexion sur la légitimité des savoirs liés aux particularismes locaux, puis sur les valeurs et finalités qui sous-tendent leur mise en oeuvre. Ces travaux permettent d’avancer une réflexion sur les évolutions de la forme scolaire face aux éducations à.
Le programme d’Histoire et éducation à la citoyenneté et l’apprentissage de la pensée historique : une analyse lexicométrique
Authors: Moreau Daniel
Published: December 2017

Cet article poursuit dans le sillage d’une analyse conceptuelle réalisée antérieurement. Dans cette analyse, nous interrogions le rapport des programmes d’histoire publiés au Québec depuis la réforme curriculaire entamée au début des années 1980 à l’apprentissage de la pensée historique. Cet article a pour objectif d’éclaircir ces divergences par une analyse lexicométrique du programme d’Histoire et éducation à la citoyenneté. Pour ce faire, une analyse factorielle des correspondances a été réalisée de manière à mettre au jour des traits structuraux spécifiques. Ces derniers rejoignent certaines propriétés associées à l'apprentissage de la pensée historique, et quelques-unes apparaissent confuses.
Connaissances psychopédagogiques générales d’enseignants du primaire à Genève1
Authors: Laflotte Lara
Published: December 2017

Dans cette contribution, nous proposons un relevé des connaissances psychopédagogiques générales des enseignants du primaire du canton de Genève par l’intermédiaire d’une analyse thématique d’entretiens semi-directifs menés auprès de 23 enseignants. Des 94 comportements rapportés, 10 ensembles de comportements sont mis en évidence. Trois axes de connaissances psychopédagogiques générales sont alors identifiés : diagnostiquer, enseigner, et gérer les aspects sociaux et disciplinaires. Ces résultats confirment et alimentent les données issues des écrits scientifiques de recherche en proposant un nouveau modèle sous forme d’une triade psychopédagogique dynamique.
Ressenya a Danvila y Collado, Manuel, La germanía de Valencia. Estudio preliminar de Pau Viciano, Pamplona: Urgoiti Editores, 2016
Authors: Roca Ricart Rafael
Published: December 2017

Ressenya a Danvila y Collado, Manuel, La germanía de Valencia. Estudio preliminar de Pau Viciano, Pamplona: Urgoiti Editores, 2016, 255 pp. ISBN: 978-84-940991-7-5 Review to Danvila y Collado, Manuel, La germanía de Valencia. Estudio preliminar de Pau Viciano, Pamplona: Urgoiti Editores, 2016, 255 pp. ISBN: 978-84-940991-7-5
Militares, cortesanos y poetas en el entorno de los infantes de Aragón (1439-1445): las Coplas de Juan de Dueñas al infante don Enrique
Authors: Rubio Vela Agustín
Published: December 2017

Resumen: A la luz de crónicas y documentos del siglo XV, las Coplas de Juan de Dueñas al infante don Enrique, poema de cancionero que constituye una fuente histórica de notable interés para el conocimiento del entorno militar, cortesano y literario de Juan de Navarra, futuro Juan II de Aragón, hubo de ser escrito en Castilla entre 1440 y 1443, años previos a la derrota en Olmedo de los infantes de Aragón.   Palabras clave: Juan de Dueñas, Enrique de Aragón, Juan de Navarra, Juan II de Castilla, siglo XV, infantes de Aragón   Abstract: The Coplas de Juan de Dueñas al infante don Enrique, a Castilian poem of the 15th century, is a historical source of notable interest to explore the military environment of the time, as well as the court and literary world of John of Navarra, who would later become John II of Aragon. An analysis of its contents, in the light of contemporary chronicles and documents, reveals it must have been written in Castile between 1440 and 1443; that is, prior to the defeat of the Infantes of Aragon in Olmedo. Keywords: Juan de Dueñas, John of Navarra, John II of Castile, Infants of Aragon, 15th century
D’àngels i dimonis. Anàlisi d’una seqüència del programa iconogràfic de la moralització enciclopèdica de la fin’amors en el Breviari d’Amor de Matfré Ermangaud
Authors: Martines Vicent
Published: December 2017

Resum: En el present treball parem esment a 3 il·luminacions del Breviari d’Amor de Matfré Ermengaut, a més de ser eloqüents –valga la sinestèsia: imatges que són eloqüents— justament d’aqueixa vocació d’Ermengaud en pro de la cristianització de la fin’amors. Estableixen una mena de seqüència en el concert de diàleg entre història natural, història sagrada i atenció a l’amor, als amadors a fi i efecte que estableix qui és el receptor concret de l’obra, qui el model a seguir (els àngels) i qui a defugir (el dimoni), i quin és l’àmbit d’actuació del «maligne»: la societat cortés, ecosistema de la fin’amor.   Paraules clau: Breviari d’amor, enciclopedisme medieval, text i imatge, fin’amor, càtars, moralitazió   Abstract: This paper analyzes three illuminations of Matfré Ermengaud´s Breviari d'Amor which represent the author´s attempt to Christianize the concept of fin'amors. In particular, they establish a connection among natural history, sacred history and love and lovers and allow us to study who is the recipient of Ermengaud's work. In addition, they serve us to study the author´s injunctions on the model to be followed (angels), the model to reject (demons), and the sphere of action of «the evil»: courtly society and the ecosystem of fin´amors. Keywords: Breviari d´Amor, Medieval encyclopedic knowledge, text and image, fin´amor, Cathars, moralization
La (re)construcció visual i retòrica de Jaume I a la Festa de l’Estendard de Mallorca durant l’època foral
Authors: Granell Sales Francesc
Published: December 2017

Resum: L’article pretén adverar de quina manera es configurava i s’identificava la figura del rei en Jaume a la Festa de l’Estendard, la commemoració anual de la conquesta cristiana de la ciutat de Mallorca, mitjançant l’anàlisi dels elements visuals i retòrics planificats per al desenvolupament d’aquella. Cal parar atenció, concretament, a dos d’aquests elements: el portaestandard que anava a cavall ben abillat amb armadura i altres objectes i l’eloqüent prèdica –coneguda com el Sermó de la Conquesta– que pronunciava un clergue acreditat per a tal funció.   Paraules clau: Jaume I, imatge règia, festes de la Baixa Edat Mitjana, iconografia del poder, Regne de Mallorca Abstract: This paper attempts to discuss the manner in which the image of king James I was customized and established in the Festa de l’Estendard, the annual commemoration ceremony of the christian conquest of the city of Mallorca. We will do so through an analysis of the visual and rhetorical elements planned for the unfolding of the ritual. One should focus particular attention on two of these elements: the standard bearer on horseback well attired in armour and other objects and the speech known as the «Sermó de la Conquesta» delivered by a cleric. Keywords: James I of Aragon, Royal Image, Late Medieval Ceremonies, Iconography of Power, Kingdom of Mallorca
Conversaçiones de Música a finals del segle XVI: el cas de l’acadèmia de Joan de Borja i Castro
Authors: Escrivà-Llorca Ferran
Published: December 2017

Resum: Aquest article s’insereix dins del conjunt d’investigacions sobre la Cort dels Habsburgs. L’estudi de les acadèmies musicals és poc conegut. A partir d’algunes investigacions sobre acadèmies literàries, l’article focalitzarà en l’acadèmia musical que Joan de Borja i Castro tenia a Madrid. En aquest sentit, si el mecenatge literari cortesà ja és un tema amb múltiples variants, l’aproximació al patrocini d’altres activitats artístiques, com el cas de la música, ho és encara més. En les següents pàgines s’aprofundirà en les diverses facetes erudites de Joan de Borja amb el fil conductor de les acadèmies, com a centre d’intel·lectualitat, de creació i promoció cultural i també personal. Per aquesta acadèmia van passar alguns dels personatges del món musical ibèric més important de l’època com Francisco Guerrero o Tomás Luis de Victoria. Aquest article pretén mostrar la importància d’aquesta acadèmia com un punt neuràlgic del mecenatge musical de les darreres dècades del segle XVI.   Paraules clau: Joan de Borja, Borja, acadèmies, Habsburgs, Música, Madrid   Abstract: This work is part of the research on The Court of Habsburg in Modern Era. The study of music academies is not quite known. From few works on literary academies, this article will focus on the music academy that of Juan de Borja i Castro hold in Madrid. In this way, if the courtly literary patronage is already an issue with multiple variants, the approach to other artistic activities, such as the music, it is even more. In the following pages, it will delve into the various aspects of erudition of Juan de Borja with the thread of the academies, as a centre of intellectual, creative and cultural promotion and personal. Some of the most important composers of the Iberian World of that time, such as Francisco Guerrero or Tomás Luis de Victoria, were involved in this academy. The article aims to show the relevance of this cenacle as a focal point of the musical patronage in the last decades of the 16th century Spain. Keywords: Joan de Borja, Borja, academies, Habsburgs, Music, Madrid
Nota su Lucrezia Borgia nella musica
Authors: Picchi Consuelo
Published: December 2017

Riasunto: Nel presente scritto si fa una riflessione sulla presenza di Lucrezia Borgia nella musica ed anche sull’interesse della figlia del papa nella musica del Tromboncino. Ancora, si vede come Donizetti rappresenta Lucrezia nella sua opera.   Parole chiave: Lucrezia Borgia, musica, Tromboncino, Donizetti   Abstract: In this paper there is a reflection on the presence of Lucrezia Borgia in music and also on the interest of the Pope’s daughter in the music of Tromboncino. Still, one sees how Donizetti represents Lucrezia in his work. Keywords: Lucrezia Borgia, music, Tromboncino, Donizetti
Ressenya a Jaume Riera i Sans, Sodomites catalans. Història i vida (segles XIII-XVIII), Barcelona, BASE, 2014.
Authors: Mompó Navarro Jacob
Published: December 2017

Ressenya a Jaume Riera i Sans, Sodomites catalans. Història i vida (segles XIII-XVIII), Barcelona, BASE, 2014, 634 pp. ISBN 978-84-1571-185-8 Review to Jaume Riera i Sans, Sodomites catalans. Història i vida (segles XIII-XVIII), Barcelona, BASE, 2014, 634 pp. ISBN 978-84-1571-185-8
Ressenya a Antoni López Quiles, Versos a plena plana: Poesia i transmissió doctrinal en la València del Barroc a la Il·lustració, València, Institució Alfons el Magnànim-CVEI, 2016.
Authors: Puig Gisbert Abel
Published: December 2017

Ressenya a Antoni López Quiles, Versos a plena plana: Poesia i transmissió doctrinal en la València del Barroc a la Il·lustració, València, Institució Alfons el Magnànim-CVEI, 2016, 318 pp. ISBN 978-84-7822-698-6 Review to Antoni López Quiles, Versos a plena plana: Poesia i transmissió doctrinal en la València del Barroc a la Il·lustració, València, Institució Alfons el Magnànim-CVEI, 2016, 318 pp. ISBN 978-84-7822-698-6
Les revistes bilingües a la Tortosa de la II República
Authors: Gombau Domingo M. Carme
Published: December 2017

Resum: Enmig d’un panorama periodístic escrit exclusivament en castellà, sorgeix el primer rotatiu escrit íntegrament en català a Tortosa: La Veu de Tortosa. El succeeix La Veu de la Comarca en la voluntat de «desvetllar la consciència catalanista de la comarca tortosina». Tots dos rotatius representen la introducció del regionalisme a les terres de l’Ebre i del catalanisme conservador, en una ciutat on predominaren els partits dinàstics espanyols durant la primera dècada del segle xx. Després del silenci de la dictadura primorriverista, apareix un setmanari homònim del de principis de segle com a plataforma de difusió d’un partit comarcal afí al de la Lliga Regionalista. En contrapartida, la revista Vida Tortosina, primer, i el quinzenari Acció, després, esdevenen els òrgans d’expressió d’Acció Catalana i representen un moderat nacionalisme d’esquerres. Regionalistes i nacionalistes pretenien fer front a la força política majoritària a Tortosa amb l’establiment de la ii República, els republicans marcel·linistes.   Paraules clau: terres de l’Ebre, premsa comarcal, catalanisme, actituds lingüístiques Abstract: In the middle of a journalistic circuit written exclusively in Spanish, comes the first newspaper written entirely in Catalan in the city of Tortosa: La Veu de Tortosa. This one is followed by La Veu de la Comarca which has the firm intention of «awake the Catalan consciousness of the district of Tortosa». Both newspapers represent the introduction of regionalism in Terres de l’ Ebre and the Catalan language in a zone dominated throughout the first decade of the twentieth century by Spanish dynastic parties. After the silence of the dictatorship of Primo de Rivera appears a homonymous weekly as a diffusion platform of a district party related to the Lliga Regionalista. In counterpart, the magazine Vida Tortosina first, and the biweekly Acció after, become organs of expression of Acció Catalana and represent a moderate progressive nationalism. Regionalists and nationalists tried to fight the greatest political force in Tortosa with the establishment of the II Republic, the «marcel·linistes» Republicans. Keywords: Ebre’s land, tortosin press, Catalanism, linguistic actitudes
Virgen de la Misericordia, San Jerónimo y San Miguel: el origen del corporativismo sedero en la Valencia bajomedieval (1465-1518).
Authors: Martínez Vinat Juan
Published: December 2017

El presente estudio indaga sobre el origen del asociacionismo sedero valenciano a través de las tres principales corporaciones fundadas en Valencia a finales de la Edad Media: la cofradía de la Misericordia de veleros de seda, la cofradía de San Jerónimo del Art de Velluters y la cofradía de tintoreros de seda de San Miguel. El análisis de sus ordenanzas confraternales y gremiales, contrastado con otras fuentes documentales de tipo contable (Llibres de Dates e Rebudes), nos permiten conocer la realidad, funcionamiento y desarrollo de tres entidades que protagonizaron el arranque de la sedería valenciana, tanto desde la perspectiva laboral como desde la óptica benéfico-asistencial, ambas inseparables en el periodo que nos ocupa.
Alfonso V el Magnánimo y el Siti Perillós (1422-1458).
Authors: Capilla Aledón Gema Belia
Published: December 2017

Alfonso V el Magnánimo, Rey de Aragón (1416-1458), constituye un caso excepcional en la representación del poder político, ya que personifica el primer monarca europeo en articular un discurso de su imagen en el que conviven y se combinan los valores y modos de representación medievales con los modernos auspiciados por el Humanismo italiano. Uno de los elementos más controvertidos e interesantes de dicho discurso lo conforman sus emblemas reales, elementos de tradición medieval que, precisamente, no sólo se mantienen sino que incluso cobran vigor al avanzar el empleo de las formas clásicas. Uno de dichos emblemas es precisamente el que mayor relación guarda con la tradición literaria medieval: el siege perilleous del Saint Graal. El objetivo del presente artículo es, por tanto, analizar el uso que el monarca realizó de dicho emblema y ofrecer la reconstrucción de su historia como elemento concreto del discurso representativo alfonsino.
Minimum time required to detect population trends: the need for long-term monitoring programs
Authors: White Easton R
Published: December 2017

Long-term time series are necessary to better understand population dynamics, assess species' conservation status, and make management decisions. However, population data are often expensive, requiring a lot of time and resources. When is a population time series long enough to address a question of interest? I determine the minimum time series length required to detect significant increases or decreases in population abundance. To address this question, I use simulation methods and examine 822 populations of vertebrate species. Here I show that on average 15.9 years of continuous monitoring are required in order to achieve a high level of statistical power. However, there is a wide distribution around this average, casting doubt on simple rules of thumb. For both simulations and the time series data, the minimum time required depends on trend strength, population variability, and temporal autocorrelation. However, there were no life-history traits (e.g. generation length) that were predictive of the minimum time required. These results point to the importance of sampling populations over long periods of time. I argue that statistical power needs to be considered in monitoring program design and evaluation. Short time series are likely under-powered and potentially misleading.
Statistical methods and transport modeling to assess PCE hotspots and diffuse pollution in groundwater (Milan FUA)
Authors: Colombo Loris
Published: December 2017

The Italian law 152/2006 adopted the EU Water Framework Directive principles and delegated to the Regions the task of identifying areas subject to groundwater diffuse pollution. In the Lombardy Plain, the qualitative groundwater conditions are affected mainly by the presence of industries and anthropic activities. The aim of this work was to assess tetrachloroethylene (PCE) diffuse pollution in the Milan Functional Urban Area (FUA), where chlorinated solvents are the main groundwater contaminants and the results of monitoring campaigns for the years 2003-2014 were collected in a dataset. For this purpose, a new methodology was implemented both in a deterministic and stochastic process. At first, hotspots were identified through Cluster Analysis (CA) applied to concentration values collected in unconfined/confined aquifers (2003-14). Then, a numerical transport model was implemented to study the hotspot plume extension in reason to identify monitoring wells not affected by diffuse pollution but related to specific hotspot sources. Consequently, it was possible to erase these data from the whole initial dataset in order to have a new one containing only diffuse concentrations. Interpolating them through ordinary kriging, PCE iso-concentrations maps identified areas where values are over the Maximum Contaminant Level (1.1 μg/l, Italian Law 152/06). Considering descriptive statistics and iso-PCE concentration maps, a median PCE value estimation (10 μg/l) was find as representative of PCE diffuse contamination Milan city. Moreover, a stochastic methodology was used in order to consider uncertainties due to unknown multiple-sources and environmental heterogeneity. The innovative approach gave some interesting solutions to point out areas where the contaminant mass release is higher and where high probability unknown sources can be found.
The Influence of Leadership Styles on Employees’ Job Satisfaction in Ethiopian Public Universities
Authors: Kebede Alemu Muleta , Demeke Getnet Worku
Published: December 2017

This study examines the influence of leadership styles on academic job satisfaction in higher education institutions in Ethiopia. The Multifactor Leadership Questionnaire and Job Satisfaction Survey were used to identify the prevailing leadership styles as perceived by employees and to review their satisfaction with the institutions, respectively. The researchers used a cross-sectional survey of academic staff working in selected public universities. A logistic regression analysis was used to assess the relationship between the independent (leadership styles/behaviors) and the dependent (employees’ job satisfaction) variables. The findings suggested that transformational leadership influenced positively faculty job satisfaction. The outcome of the research will generate greater awareness on the importance of having leaders whose behaviors/styles increase faculty job satisfaction and ensure organizational effectiveness.

Keywords: Leadership, Transformational Leadership, Transactional Leadership Passive/Avoidant Leadership, Job Satisfaction

To cite this document: Alemu Muleta Kebede and Getnet Worku Demeke, "The Influence of Leadership Styles on Employees’ Job Satisfaction in Ethiopian Public Universities", Contemporary Management Research, Vol.13, No.3, pp. 165-176, 2017.

Permanent link to this document:
http://dx.doi.org/10.7903/cmr.17668
Carbon Fibers
Authors: Newcomb Bradley A.
Published: December 2017

Carbon fibers have high strength, high modulus, compressive strength, shear modulus, and low density. These properties make them useful reinforcement materials in applications in the aerospace, automotive, sporting goods, energy, biomedical, and other industries.

In this article, mature processing methods of carbon fiber from polyacrylonitrile (PAN) and pitch are discussed, as well as more recent methods of processing carbon nanotubes and graphene fibers. Structure, morphology, properties, and applications of carbon fibers are also discussed.
Mass Transfer
Authors: Chisti Yusuf
Published: December 2017

Mass transport phenomena influence all kinds of processes, often controlling the rate, the yield, the product spectrum, and product recovery. This article details the mass transfer considerations in production and processing of chemicals. Fundamentals of mass transfer are discussed for gas–liquid, liquid–liquid, and solid–liquid systems. Methods for measurement of the overall gas–liquid volumetric mass transfer coefficient (
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a
L
) are noted. Mass transport behavior is discussed for various kinds of reactors: laboratory shake flasks, vortex aerated devices, stirred tanks, bubble columns, airlift reactors, fluidized beds, packed beds, and other systems. Prediction and estimation of the various mass transfer coefficients are emphasized. Mass transfer within particles is treated as being relevant to adsorption, ion exchange, chromatographic separations, and heterogeneous catalysis. Mass transport in membrane processing is outlined.
Radioisotopes
Authors: Starovoitova Valeriia
Published: December 2017

Radioisotopes, also called radionuclides, are unstable atoms that spontaneously decay to more stable elements or other atoms by emission of matter or energy. Radioisotopes are routinely used to determine the ages of materials, for diagnostics and treatment of diseases, for nondestructive evaluation of materials, for the tracking of groundwater or air flow, for food sterilization, and for many other applications.

This article summarizes the nuclear physics properties of radioisotopes and the various radiation particles, including the concepts of half‐life, decay constant, angular momentum, and parity. The modes of nuclear decay and the accompanying radiation are described, as are combined nuclear and atomic processes, and atomic decays and corresponding radiations. Applications for science, medicine, and industry uses of various isotopes are discussed and their production methods are described.
Reactor Technology
Authors: Mann Uzi
Published: December 2017

Chemical reactor technology is concerned with the selection, design, and operation of a chemical reactor– an equipment unit in a chemical process where chemical transformations (reactions) take place to generate a desirable product at a specified production rate, using a given chemistry.

The reactor type (configuration) and its operating conditions are selected to achieve objectives, such as maximizing the profit of the process, and minimizing the generation of pollutants, while satisfying design and operating constraints, including safety, controllability, availability of raw materials, etc. A chemical reactor plays a pivotal role in the operation and economics of the entire process because its performance affects other units in the process such as separation units, utilities, etc.

In this article, design considerations of typical reactor configurations and the underlying physical and chemical principles are discussed. Common engineering practices that are applied during chemical reactor development are reviewed. These include experimental reactors, selection of reactor type and configuration, selection of operating conditions, and diagnostics of existing reactors. Examples of industrial reactors are described.
Timing and Distribution of Single‐Layered Ejecta Craters Imply Sporadic Preservation of Tropical Subsurface Ice on Mars
Authors: Kirchoff Michelle R. , Grimm Robert E.
Published: December 2017

Determining the evolution of tropical subsurface ice is a key component to understanding Mars's climate and geologic history. Study of an intriguing crater type on Mars—layered ejecta craters, which likely form by tapping subsurface ice—may provide constraints on this evolution. Layered ejecta craters have a continuous ejecta deposit with a fluidized‐flow appearance. Single‐layered ejecta (SLE) craters are the most common and dominate at tropical latitudes and therefore offer the best opportunity to derive new constraints on the temporal evolution of low‐latitude subsurface ice. We estimate model formation ages of 54 SLE craters with diameter (D) ≥ 5 km using the density of small, superposed craters with D < 1 km on their continuous ejecta deposits. These model ages indicate that SLE craters have formed throughout the Amazonian and at a similar rate expected for all Martian craters. This suggests that tropical ice has remained at relatively shallow depths at least where these craters formed. In particular, the presence of equatorial SLE craters with D ~ 1 km indicates that ice could be preserved as shallow as ~100 m or less at those locations. Finally, there is a striking spatial mixing in an area of highlands near the equator of layered and radial (lunar‐like ballistic) ejecta craters; the latter form where there are insufficient concentrations of subsurface ice. This implies strong spatial heterogeneity in the concentration of tropical subsurface ice.
Longitudinal and Temporal Evolution of the Tectonic Style Along the Cyprus Arc System, Assessed Through 2‐D Reflection Seismic Interpretation
Authors: Symeou Vasilis , Homberg Catherine , Nader Fadi H. , Darnault Romain , Lecomte Jean‐Claude , Papadimitriou Nikolaos
Published: December 2017

The Cyprus Arc system constitutes a major active plate boundary in the eastern Mediterranean region. This structure is directly linked with the northward convergence of the African and Eurasian plates since the Late Cretaceous. Two‐dimensional reflection seismic data were utilized, which image the main plate structures and their lateral evolution south of the island of Cyprus. Interpretation of these data allowed the identification of nine tectono‐sedimentary packages in three different crustal domains south of the Cyprus Arc system: (1) the Levant Basin (attenuated continental crust), (2) the Eratosthenes microcontinent (continental crust), and (3) the Herodotus Basin (oceanic crust). Within these domains, numerous tectonic structures were documented and analyzed in order to understand the mechanism and timing of deformation. In the north, south verging thrusting commenced in early Miocene along the Larnaca and Margat ridges, whereas no activity was identified before middle Miocene along the Latakia Ridge. Thus, the deformation front migrated southward and was accompanied by the development of flexural basins and stratigraphic onlaps as in the Cyprus Basin. The acme of deformation occurred in mid‐late Miocene. A regional unconformity of Pliocene age marks the end of the first deformation sequence. In Plio‐Pleistocene time, the westward escape of the Anatolian microplate resulted in the reactivation of existing structures. The evolution of deformation along the plate boundary is identified from the creation of positive flower structures revealing transpressive movements along the Larnaca and Latakia Ridges (eastern domains), whereas in the Eratosthenes domain a flexural basin highlights a compressive regime.
Fundamentals: Introduction and Survey
Authors: Stein Erwin
Published: December 2017

This chapter first provides a motivation and the scope of the whole encyclopedia, especially the mathematically oriented fundamentals with rapidly developing generalizations of classical FEMs and new strategies. Then, the stages of historical developments and features of computational mechanics are outlined for four essential development stages. The main third section presents the reviews and appreciations of the 28 articles in Volume 1, among them 6 new contributions. The last section What We Do Expect presents expected trends of future scientific and applied developments that become necessary of multiconnected challenges from natural and engineering sciences as well as planning, developing, and production of systems of products in industry and their maintenance.
Interpolation and Quasi‐Interpolation inh‐ andhp‐Version Finite Element Spaces
Authors: Apel Thomas , Melenk Jens M.
Published: December 2017

Interpolation operators map a function to an element of a finite element space. Unlike more general approximation operators, interpolants are defined locally. Estimates of theinterpolation error, that is, the difference , are of utmost importance in numerical analysis. These estimates depend on the size of the finite elements, the polynomial degree employed, and the regularity of . In contrast to interpolation the term quasi‐interpolation is used when the regularity is so low that interpolation has to be combined with regularization. This chapter gives an overview of different interpolation operators and their error estimates. The discussion includes the ‐version and the ‐version of the finite element method, interpolation on the basis of triangular/tetrahedral and quadrilateral/hexahedral meshes, affine and nonaffine elements, isotropic and anisotropic elements, and Lagrangian and other elements.
Thep‐Version of the Finite Element and Finite Cell Methods
Authors: Düster Alexander , Rank Ernst , Szabó Barna
Published: December 2017

In the first part of this chapter, the basic algorithmic structure and performance characteristics of thep‐version of the finite element method (FEM) are surveyed with reference to elliptic problems in solid mechanics. For this class of problems, the theoretical basis of thep‐version is fully established, and a very substantial amount of engineering experience covering linear and nonlinear applications is available. It is shown thatp‐extensions on properly designed meshes make realization of exponential rates of convergence in practical computations possible and provide for the estimation and control of relative errors in terms of any quantity of interest. In the second part, thep‐version of the FEM is extended to a high‐order fictitious domain approach, the finite cell method (FCM). While the FCM inherits the advantages of thep‐version with respect to accuracy and robustness, it relieves analysts from the necessity of generating finite element meshes. Thus, it strongly supports the analysis of problems with highly complicated geometry, for which meshing with finite elements would be very difficult. Given the growing demand for verified numerical solutions, thep‐version of the finite element and FCMs are expected to play an increasingly important role.
Spectral Methods
Authors: Canuto Claudio , Quarteroni Alfio
Published: December 2017

Spectral methods represent a family of methods for the numerical approximation of partial differential equations. Their common denominator is to rely on high‐order polynomial expansions, notably trigonometric polynomials for periodic problems, and orthogonal Jacobi polynomials for nonperiodic boundary‐value problems. They have the potential to provide a high rate of convergence when applied to problems with regular data. They can be regarded as members of the broad family of (generalized) Galerkin methods with numerical evaluation of integrals based on Gaussian nodes. In the first part, we introduce the methods on a computational domain of simple shape and analyze their approximation properties as well as their algorithmic features. Next, we address the issue of how these methods can be extended to more complex geometrical domains by retaining their distinctive approximation properties.
Meshfree Methods
Authors: Huerta Antonio , Belytschko Ted , Fernández‐Méndez Sonia , Rabczuk Timon , Zhuang Xiaoying , Arroyo Marino
Published: December 2017

The aim of this chapter is to provide an in‐depth presentation and survey of meshfree particle methods. Several particle approximations are reviewed; the SPH method, corrected gradient methods, the moving least‐squares (MLS) approximation, and maximum‐entropy approximations. The discrete equations are derived from a collocation scheme or a Galerkin method. Special attention is paid to the treatment of essential boundary conditions. Finally, different approaches for modeling discontinuities in meshfree methods are described, including peridynamics and phase‐fields.
Boundary Element Methods: Foundation and Error Analysis
Authors: Hsiao George C. , Steinbach O. , Wendland W. L.
Published: December 2017

This chapter gives an expository introduction to the Galerkin‐BEM for the elliptic boundary value problems from the mathematical point of view. Emphasis will be placed on the variational formulations of the boundary integral equations (BIEs) and the general error estimates for the approximate solution in appropriate Sobolev spaces. A classification of BIEs will be given on the basis of the Sobolev index. The simple relations between the variational formulations of the BIEs and the corresponding partial differential equations under consideration will be indicated. Basic concepts such as stability, consistency, and convergence as well as the condition numbers and ill‐posedness, will be discussed by using elementary examples.

This is the second edition of this chapter. The first edition was published in 2004. In this edition, additional topics have been included and discussed. These additional topics are concerned with the BIE‐method for a higher‐order elliptic equation, trace theorem and boundary spaces as well as numerical experiments for standard and fast multipole BEMs.
Coupling of Boundary Element Methods and Finite Element Methods
Authors: Stephan Ernst P.
Published: December 2017

For the numerical treatment of elliptic boundary value problems, the coupling of boundary element methods (BEM) and finite element methods (FEM) is widely used. Usually, the FEM is applied in a bounded subdomain, whereas the BEM subdomain may be unbounded, but without inhomogeneous or nonlinear material behavior. This article gives a survey of FE/BE coupling for elliptic interface problems from a mathematical perspective. We concentrate on the symmetric coupling method because of its general applicability and give
a priori
and
a posteriori
error estimates. Further, we address implementational aspects such as suitable preconditioning for appropriate solvers of the Galerkin equations. As new developments, we consider a least squares coupling method with first‐order systems in the FEM domain and consider both primal and dual FE/BE coupling methods for interface problems with Signorini contact condition. Besides standard formulations, mixed FEM formulations are also considered. Applications in elasticity are discussed. We present proofs of essential theorems because we feel that these proofs are essential for understanding the mathematical aspects. We also present illustrative numerical examples and provide a list of references to the current literature. The new version contains sections on convergence of an adaptive coupling algorithm and on nonsymmetric coupling methods
Multigrid Methods forFEMandBEMApplications
Authors: Hackbusch Wolfgang
Published: December 2017

After discretizing the partial differential equations from mechanics, one usually obtains large systems of (non)linear equations. Their efficient solution requires the use of fast iterative methods. Multigrid iterations are able to solve linear and nonlinear systems with a rather fast rate of convergence, provided the problem is of elliptic type. This contribution describes the basic construction of multigrid methods, their ingredients, related methods, and their application to various problem classes. Although most of the applications concern FEM (finite element method) discretizations of partial differential equations, there are also applications to integral equations as they occur in boundary element methods (BEMs).
Panel Clustering Techniques and Hierarchical Matrices forBEMandFEM
Authors: Hackbusch Wolfgang
Published: December 2017

The panel clustering method and the hierarchical matrix technique described here are important tools for the efficient treatment of fully populated matrices that arise from boundary element method (BEM) problems and elliptic finite element method (FEM) problems.
Computational Fracture Mechanics
Authors: Ingraffea Anthony R. , de Borst René
Published: December 2017

The purpose of this article is to survey examples of historical and state‐of‐the‐art approaches of computational fracture mechanics (CFM). Approaches are described and compared for their use in both the traditional role of CFM – calculation of crack‐front fields – and the emerging role of prediction of material‐damage evolution and toughness.
Computational Geomechanics Including Consolidation
Authors: Carter John P. , Small John C.
Published: December 2017

A review is presented of the role of computational mechanics in geotechnical engineering. Discussions of the conventional deterministic techniques used for numerical modeling in geomechanics and a brief discussion of the stochastic techniques for dealing with the uncertainties encountered in geotechnical practice are included. Considerable emphasis is given to the methods commonly used for the solution of boundary and initial value problems. Significantly, the chapter also includes a discussion of the limitations of the various numerical modeling techniques. Constitutive modeling of soil and rock mass behavior and material interfaces is an essential component of this type of computing, and so a review of recent developments and capabilities of constitutive models for geomaterials is also included. Problems involving the interaction of the ground with other engineering structures are also addressed. Some of the concepts described in the paper are illustrated with examples taken from research and practice. Emphasis has been placed on the mechanical behavior of soil, but it is noted that many of the models and techniques described also have application in rock mechanics and rock engineering.