bluuebunny/crossref_metadata_2025 huggingface dataset:
Democracy and Truth
Authors: Lever Annabelle
Published: March 2021

Selon Misak et Talisse, le fait que nous tenions nos croyances pour vraies quelles que soient les différences et les incompatibilités entre nos convictions, fournit des raisons pour préférer la démocratie à tout mode de gouvernement non-démocratique. D’où leur affirmation que la démocratie est une condition nécessaire, quoique insuffisante, pour arriver à des croyances épistémiquement justifiées. Cet article propose de clarifier, de manière critique, cette affirmation.
Democracy and Epistemic Egalitarianism
Authors: Gerber Dominik
Published: March 2021

Dans leur approche non-instrumentaliste fondée sur l’épistémologie pragmatiste de Charles Sanders Peirce, Cheryl Misak et Robert Talisse proposent une version unique et importante des justifications épistémiques de la démocratie, suivant l’argument que la démocratie est un élément constituant de l’idéal peircien de l’enquête. Cet article interprète cet idéal comme reposant sur une conception relationnelle de l’égalité épistémique. L’article avance aussi que cette conception ne peut pas donner lieu à une justification sans équivoque d’institutions réalisant une conception d’égalité politique. L’objectif plus général est de mettre en garde contre l’emploi des affinités conceptuelles entre l’égalité démocratique, ses incitations à l’autoréflexion parmi les citoyens, et les relations épistémiques intrinsèquement valables pour fonder une justification de la démocratie.
Epistemic Democracy Without Truth: The Deweyan Approach
Authors: Fuerstein Michael
Published: March 2021

Dans cet article, je mets l’approche pragmatiste deweyenne de l’épistémologie démocratique en relation avec l’approche contemporaine de la « démocratie épistémique ». De manière similaire aux démocrates épistémiques, John Dewey caractérise la démocratie comme une forme d’enquête sociale. Or, alors que les démocrates épistémiques suggèrent que la démocratie vise à « poursuivre la vérité », Dewey rejette la notion de « correspondance » à la vérité dans le domaine politique tout comme dans les autres domaines. Pour Dewey, la mesure du succès d’une prise de décision ne découle pas d’un standard indépendant et fixe de vérité ou d’exactitude, mais de notre propre satisfaction réflexive à l’égard des résultats pratiques obtenus. Je soutiens que cette approche réconcilie mieux la démocratie épistémique avec les modèles traditionnels d’autorité populaire (« la volonté du peuple ») et renforce la conception des démocrates épistémiques pour opposer les alternatives élitistes.
Sur les chemins de la normalisation
Authors: Coutant Hadrien , Finez Jean , Viallet-Thévenin Scott
Published: March 2021

Les transformations des entreprises publiques participent des métamorphoses de l’action de l’État dans l’économie. À rebours d’une littérature qui les essentialise ou postule une modalité unique de relation à l’État, nous qualifions leurs transformations en mobilisant la notion de « conception de contrôle » – définie comme la combinaison du capital, du gouvernement, des objectifs d’une entreprise et du marché sur lequel elle opère. L’analyse historique et comparative de trois grandes firmes – la sncf , Safran et edf  – permet de décrire le processus de normalisation des entreprises publiques depuis les années 1960. L’article met en évidence trois processus distincts, l’isolation, l’adjonction et la conversion, qui affectent la conception du contrôle de chacune d’elles, selon leurs spécificités.
Les « plans fonciers ruraux » au Bénin (1992-2015). La carrière d’un instrument « pilote » au sein de politiques non stabilisées
Authors: Lavigne Delville Philippe
Published: March 2021

Inventé en Côte d’Ivoire au milieu des années 1980, le Plan foncier rural (PFR) est un des instruments mis au point dans le cadre de l’aide internationale pour permettre la formalisation des droits fonciers coutumiers, individuels et collectifs. Il a été importé au Bénin au début des années 1990, dans l’optique de contribuer à une future réforme foncière. En 25 ans, le PFR y a joué différents rôles successifs : il a été un instrument de promotion d’une réforme, puis l’instrument central d’une politique de formalisation des droits coutumiers, individuels ou collectifs, et enfin un moyen au service d’une politique de privatisation, avant d’être récemment marginalisé au profit du cadastre. À travers ce cas, ce sont les liens problématiques entre politiques publiques et instruments que l’on se propose d’analyser, en montrant l’autonomie relative de l’instrument PFR par rapport aux politiques successives, sa dimension composite et adaptative, et la façon dont les débats sur lui révèlent les tensions autour de la politique elle-même. Alors que les instruments sont censés être des moyens de mise en œuvre d’une politique, ici, l’instrument a précédé la politique, et perdure en s’adaptant à ses reformulations, dans une greffe qui demeure incertaine.
Réguler les universités par les instruments. Expériences de l’enseignement supérieur au Kenya et en Ouganda
Authors: Provini Olivier
Published: March 2021

L’objectif de cet article consiste à discuter – à partir des exemples kenyan et ougandais – les ressorts de la nouvelle ingénierie universitaire qui se fabrique et se met en œuvre dans la région de l’Afrique de l’Est. Deux principaux instruments structurant le secteur de l’enseignement supérieur sont pris en exemple : les normes d’assurance qualité et les objectifs nationaux régulant, dans les programmes de développement des gouvernements, les pratiques sur les savoirs. Nous démontrons que lorsque l’on s’arrête sur la fabrique de ces Instruments d’Action Publique (IAP), nos deux études de cas présentent des trajectoires similaires, tant sur la nature de ces instruments que sur les acteurs qui les impulsent. Pour autant, les cas kenyans et ougandais donnent à voir des résultats contrastés sur la mise en œuvre des IAP et, plus largement, sur les réformes d’enseignement supérieur. Alors que le cas kenyan de l’Université de Nairobi valide l’importance prise par les IAP dans la régulation du secteur et de ses institutions, l’exemple ougandais de l’Université de Makerere illustre plutôt les décalages et les effets originaux et non désirés qui peuvent se produire lors de l’implémentation des IAP.
La liaison ferroviaire Chine-Kirghizstan-Ouzbékistan : un tortueux chemin
Authors: Ren Sijie , Lasserre Frédéric
Published: March 2021

Conçu depuis 1996, le projet de construction du chemin de fer Chine-Kirghizstan-Ouzbékistan, reliant l’Ouest du Xinjiang à l’Asie centrale via le Kirghizstan, reste encore en suspens. Malgré l’importance de cette connexion ferroviaire pour les pays concernés et les demandes massives d’infrastructures en Asie centrale, des désaccords fondamentaux, comme le tracé de la ligne au Kirghizstan, le montage financier et l’écartement des voies, freinent l’avancée du projet. Or cette liaison ferroviaire est stratégique pour la Chine dans ses projets de développement d’interconnexions vers le Moyen-Orient d’une part, et afin de fluidifier les flux de marchandises d’autre part.
La stratégie de sécurité de la Turquie : une nouvelle doctrine d’emploi des forces armées à l’étranger
Authors: Boz-Acquin Élise
Published: March 2021

Le dilemme de la politique étrangère turque, condamnée à un équilibrage actif de ses relations d’une part pour remédier à l’indécision, voire le flou stratégique, des États-Unis et de l’Europe au Moyen-Orient, d’autre part pour faire face à l’hégémonie russe dans la région, s’est transformé en une véritable contrainte stratégique pour Ankara. La Turquie a fait le choix de réévaluer le concept et la doctrine d’emploi de ses forces armées à l’étranger, en élaborant une vision stratégique alliant le hard power au soft power , pour mieux satisfaire ses intérêts nationaux. Elle s’efforce ainsi de mettre en œuvre une politique étrangère indépendante en tenant compte des évolutions régionales et des réalités tirées du terrain, sans s’éloigner de la realpolitik, afin de limiter toute dépendance stratégique.
Nonconstant positive solutions to the ratio-dependent predator-prey system with prey-taxis in one dimension
Authors: Cao Qian , Cai Yongli , Luo Yong
Published: March 2021

Resorting to M.G. Crandall and P.H. Rabinowitz's well-known bifurcation theory we first obtain the local structure of steady states concerning the ratio–dependent predator–prey system with prey-taxis in spatial one dimension, which bifurcate from the homogeneous coexistence steady states when treating the prey–tactic coefficient as a bifurcation parameter. Based on this, then the global structure of positive solution is established. Moreover, through asymptotic analysis and eigenvalue perturbation we find the stability criterion of such bifurcating steady states. Finally, several numerical simulations are performed to show the pattern formation.
Dependent delay stability characterization for a polynomial T-S Carbon Dioxide model
Authors: Elmajidi Azeddine , Elmazoudi Elhoussine , Elalami Jamila , Elalami Noureddine
Published: March 2021

By extending some linear time delay systems stability techniques, this paper, focuses on continuous time delay nonlinear systems (TDNS) dependent delay stability conditions. First, by using the Takagi Sugeno Fuzzy Modeling, a novel relaxed dependent delay stability conditions involving uncommon free matrices, are addressed in Linear Matrix Inequalities (LMI). Then, as application a Nonlinear Carbon Dioxide Model is used and rewritten by a change of coordinate to the interior equilibrium point. Next, by using the non-linearity sector method the model is transformed to a corresponding Fuzzy Takagi Sugeno (TS) multi-model. Also, the maximum delay margin to which the model is stable, is identified. Finally, to prove the analytic results a numerical simulation is also performed and compared to other methods.
Frequency domain $ H_{\infty} $ control design for active suspension systems
Authors: Mrazgua Jamal , Tissir El Houssaine , Ouahi Mohamed
Published: March 2021

A methodology for fault-tolerant-control(FTC) is proposed that compensates actuator failures in active suspension systems (ASS). This methodology is based on a Frequency Domain approach that represents failures using a scale factor to optimize the ASS and improve ride comfort. The controller design is carried out using off-the-shelf tools based on linear matrix inequalities (LMIs), guaranteeing asymptotic stability, compensating the effect of actuator faults, and ensuring certain \begin{document}$ H_{\infty} $\end{document} performance. In the context of ASS, the performance guarantees correspond to ride comfort in the presence of road disturbances. To validate the approach, controllers are developed and tested in simulation for a quarter-car model: the results illustrate the effectiveness of the proposed approach.
The entry and exit game in the electricity markets: A mean-field game approach
Authors: Aïd René , Dumitrescu Roxana , Tankov Peter
Published: March 2021

We develop a model for the industry dynamics in the electricity market, based on mean-field games of optimal stopping. In our model, there are two types of agents: the renewable producers and the conventional producers. The renewable producers choose the optimal moment to build new renewable plants, and the conventional producers choose the optimal moment to exit the market. The agents interact through the market price, determined by matching the aggregate supply of the two types of producers with an exogenous demand function. Using a relaxed formulation of optimal stopping mean-field games, we prove the existence of a Nash equilibrium and the uniqueness of the equilibrium price process. An empirical example, inspired by the UK electricity market is presented. The example shows that while renewable subsidies clearly lead to higher renewable penetration, this may entail a cost to the consumer in terms of higher peakload prices. In order to avoid rising prices, the renewable subsidies must be combined with mechanisms ensuring that sufficient conventional capacity remains in place to meet the energy demand during peak periods.
Ensemble monastique ou domaine privé du haut Moyen Âge ? Le site des Communaux – ZAC PIDA à Aoste (Isère)
Authors: Ancel Marie-José
Published: March 2021

Une opération d’archéologie préventive menée à Aoste en 2016, sur une surface d’environ 17 000 m², a mis au jour une église paléochrétienne dont les fondations sur pieux ont pu être datées par 14C de la fin du ve-début du vie siècle. Vingt-trois sépultures à inhumation du haut Moyen Âge sont associées à cet édifice. Elles sont essentiellement localisées à l’extérieur, contre les murs ; quelques-unes, probablement privilégiées, sont situées à l’intérieur, au niveau du porche et de la nef. On notera la présence d’immatures (12 individus) et d’adultes (17 individus).Cette église est implantée au sein d’un enclos fossoyé qui couvre une superficie d’environ 2 700 m². Elle y est associée à quelques bâtiments d’habitation sur poteaux, situés à une vingtaine de mètres. Plusieurs phases sont sans doute envisageables, avec semble-t-il au maximum quatre bâtiments fonctionnant simultanément. Un autre bâtiment sur poteaux, de plus grandes dimensions, situé dans l’axe de l’entrée de l’église, pourrait revêtir une fonction communautaire. D’autres installations évoquant des activités agricoles et/ou pastorales ont également été mises en évidence, ainsi que les fondations d’une probable tour et un puits. La durée globale d’occupation du site s’étend jusqu’au viie et probablement jusqu’aux ixe-xe siècles.Il est proposé d’interpréter le site comme un ensemble monastique, ce qui en ferait un des plus précoces de France et un des rares fouillés intégralement. Toutefois, la possibilité qu’il s’agisse d’un domaine aristocratique doté d’un petit oratoire privé reste envisageable.
Un simple tas d’os ? Le fonctionnement complexe d’un ossuaire médiéval du cimetière paroissial de l’église Notre-Dame de Boulonge-sur-Mer (Pas-de-Calais)
Authors: Blamangin Olivier , Oudry Sophie , Kacki Sacha
Published: March 2021

La collecte et le dépôt secondaire d’ossements constituaient des gestes funéraires communs dans le cadre de la gestion des espaces cimétériaux médiévaux. Les accumulations d’ossements qui en résultent ne bénéficient que rarement de fouilles archéologiques minutieuses et d’études approfondies. La fouille récente d’une fosse ossuaire dans le cimetière paroissial de l’église Notre-Dame de Boulogne-sur-Mer montre pourtant que ce type de structure ne peut être réduit à la simple expression d’une gestion pragmatique des restes humains. Dans l’exemple boulonnais, bien daté du xive siècle par des analyses 14C, quatre sépultures primaires ont été opérées dans l’ossuaire – trois jeunes enfants dont deux sont déposés en cercueil et un adulte déposé sur le ventre –, témoignant de la coexistence de deux fonctions, de deux « intentions » et de divers « temps funéraires » dans le fonctionnement de la structure. Les résultats obtenus conduisent à discuter le sens qu’il convient de donner à ces gestes funéraires atypiques que l’on rencontre quelquefois sur d’autres sites.
Un os de vautour dans la basse cour du château de Broue (xive siècle, Saint-Sornin, Charente-Maritime)
Authors: Barme Maude , Clavel Benoît
Published: March 2021

La découverte récente d’un os de vautour moine sur le site castral de Broue (France, Charente-Maritime) conduit à s’interroger sur une potentielle valorisation de cet oiseau, voire un possible négoce de tout ou partie de ce dernier. Après avoir dressé un état des lieux des découvertes de restes de vautour moine en contextes archéologiques médiévaux et modernes, les auteurs se sont interrogés sur les usages possibles des plumes, voire de la dépouille de l’oiseau. L’hypothèse du vautour captif a également été abordée car la détention d’un tel volatile, rare dans l’espace charentais, pouvait revêtir un caractère ostentatoire. Cette modeste contribution, en s’appuyant sur l’examen conjugué des sources archéozoologiques et des sources textuelles tente, autant que faire se peut, de cerner le statut du vautour, en général, et du vautour moine, en particulier, aux époques médiévale et moderne.
Une fenêtre archéologique sur l’agglomération de Moissac (Tarn-et-Garonne) du xiie au xixe siècle
Authors: Lefebvre Bastien
Published: March 2021

Entre 2015 et 2018, plusieurs campagnes de fouille programmée ont été engagées, dans le cadre d’une recherche sur la formation de l’agglomération, au sud du monastère Saint-Pierre de Moissac. La puissance stratigraphique importante, la grande quantité de structures et la très bonne conservation des matériaux organiques due au sous-sol humide ont permis de documenter les dynamiques de l’occupation domestique dans un secteur de la ville entre le xiie et le xixe siècle. Si l’un des principaux résultats de cette recherche a été de mettre en évidence que le développement de l’agglomération n’est vraisemblablement pas antérieur à la seconde moitié du xiie siècle, les données recueillies concernant l’occupation domestique se sont révélées riches, avec la mise au jour d’une grande variété de mobilier en position de rejet, et la découverte de structures originales, comme un grand pressoir à levier construit à la fin du xiiie siècle.
Improving Reading Comprehension of Third-Grade Students Through a Serious-Game Prototype
Authors: Gaytán-Lugo Laura S.
Published: March 2021

According to national and international assessment results, there is a serious problem regarding reading comprehension skills in Mexico, specifically global reading comprehension. Different tools and techniques have been used to try to minimize this problem. Serious games with educational purposes are a popular tool, as they are useful in developing abilities or improving learning on top of being fun to play. This chapter presents the use of a prototype of a serious game to improve global reading comprehension in children attending the third grade of primary school. The instruction design was empathizing in the design section. Through a quasi-experiment during a four-month period, the game was tested in five third-grade students. Results show a significant improvement in their global reading comprehension skill. However, as future work, and after the quarantine, a bigger sample size is required to generalize findings.
Translanguaging and Digital Technologies in the Realm of Language Learning
Authors: Tzirides Anastasia Olga
Published: March 2021

In the globalized world that we live in, people communicate by using not only their primary language, but all the languages they know complemented by the use of multimodal elements, like images, videos, emoticons, memes, and more. This idea of using the whole linguistic and semiotic repertoire for communication is called translanguaging. This chapter focuses on the notion of translanguaging and explores its implementation in relation to digital tools. It offers an evolution of the definition of translanguaging, and it continues by analyzing it as a theoretical and pedagogical approach. It also explores, based on the literature, the way that translanguaging can be practically implemented in educational practice and in combination with digital technologies. This chapter provides cases and examples of digital translanguaging, and it concludes by determining the gaps in the literature and the potential future steps in this area.
Error-State Extended Kalman Filter-Based Sensor Fusion for Optimized Drive Train Regulation of an Autonomous PHEV
Authors: Jose Chacko Parag , K. M. Haneesh , Rodrigues Joseph X.
Published: March 2021

An efficient state estimator is critical for the development of an autonomous plug-in hybrid electric vehicle (PHEV). To achieve effective autonomous regulation of the powertrain, the latency period and estimation error should be minimum. In this work, a novel error state extended kalman filter (ES-EKF)-based state estimator is developed to perform sensor fusion of data from light detection and ranging sensor (LIDAR), the inertial measurement unit sensor (IMU), and the global positioning system (GPS) sensors, and the estimation error is minimized to reduce latency. The estimator will provide information to an intelligent energy management system (IEMS) to regulate the powertrain for effective load sharing in the PHEV. The integration of the sensor fusion data with the vehicle model is simulated in MATLAB environment. The PHEV model is fed with the proposed state estimator output, and the response parameters of the PHEV are monitored.
Education Faculty Lived Experiences of Student Interaction and Engagement in Online Courses
Authors: Eteokleous Nikleia , Panaoura Rita
Published: March 2021

In this chapter, the two authors co-construct meaning of their individual lived experiences as education faculty engaging in online teaching and learning. It highlights each faculty unique experiences facilitating graduate student learning in an online environment. Co-construction of meaning centers on pedagogical approaches, program design and focus, reflection of faculty-self experiences, employment of digital learning tools, and utilization of best practices of each faculty experience with teaching and learning in an online environment. This narrative is co-constructed following a collaborative autoethnographic approach by two faculty, whereby the central descriptions of each faculty member is situated in one's lived experiences and rich story of facilitating and instructing courses in an online learning environment. The faculty experiences are mainly derived from teaching graduate courses offered by a department of education. The research method in presenting two self-reflective narratives in online teaching and learning extends to doing “collaborative autoethnography.”
Adolescent Development
Authors: Sax Alessandra
Published: March 2021

In the chapter, adolescent development, brain development, positive and negative effects of social media on academic achievements, and the educational experiences of young, virtual learners will be examined. Further discussion will entail the importance of social-emotional competencies found in learners that contribute and enhance students' overall positive functioning in academic settings. Pertinent research and literature related to the above stated themes, will also be explored, analysed, and discussed within the context of the chapter's framework.
Educational Leadership
Authors: Grigoropoulos Jenny E.
Published: March 2021

Leadership is a field studied considerably since ancient years. Leadership scholars concentrate on the innate traits that born leaders have, while others focus on the traits attained throughout a person's life. Another common notion is that mainly individuals in higher positions in organizations practice leadership. Although students of leadership mainly study it during their university years, the plethora of leadership educational programs often teach on a theoretical basis leading to partial application to real-world cases. Recent research has surfaced the need to enrich primary and secondary education and curricula with instructional methodologies, which instill leadership qualities to students, like ethos, empathy, and compassion, while providing students with skills and capabilities essential to develop effective leaders of tomorrow. Additionally, educating young students to become accountable, compassionate, and kind while enriching their learning with service mindedness and the cultivation of belonging, collaboration, and interaction builds character and leadership qualities.
Inspiring Inquiry With the i2Flex Model in the World Language Classroom
Authors: Rocha Christina J.
Published: March 2021

This chapter introduces different methods for how to incorporate inquiry-based learning (IBL) practices with i2Flex methodology, both virtually as well as in the traditional world language classroom model using updated and relevant 21st century skills. Using the teacher as a constructivist model, the question formulation technique, design thinking, content and project based learning, learning among others are all explored in depth so the WL teacher can apply theory through practical examples that support a global understanding and context. World languages can be ESL, Spanish, Greek, Nahuatl, or any other WL(s) taught and spoken across cultures.
Influence of Machine Parameters on Ti-6Al-4V Small Sized Specimens Made by Laser Metal Powder Deposition
Authors: Milhomme Sarah , Lartigau Julie , Brugger Charles , Froustey Catherine , Dufau Ludovic
Published: March 2021

The present work is focused on one Additive Manufacturing (AM) process – Laser powder Metal Deposition (LMD-p) – and on one metallic alloy – Ti-6Al-4V. State of the art on LMD-p on Ti-6Al-4V alloy shows that three kinds of process parameters influence mechanical properties of building parts: raw materials (powder and substrate), machine parameters (Laser Power (P), Powder Flow (F) and Building Speed (V)), and building strategies (part orientation, waiting time between layers, etc.). Thus, this paper relates to first manufacturing investigations on small sized specimens (bead, wall and block) with the aim of providing a better knowledge about the first steps of manufacturing. Particularly, this paper is dedicated to the study of machine parameters (P, F and V). First, the influence of each machine parameter on 28 beads is studied separately. The geometrical aspect (high, width, dilution) of each bead is microscopically measured. Similarly, combinations of parameters (P/F, Energy Density and Powder Density) are introduced to increase parameters degree of freedom. First results show that P, V and F have a major influence on the beads’ geometry. In addition, a window process map is plotted and allows determining functional areas of machine parameters. From this map, walls (vertical superposition of one bead) are manufactured and microscopically observed. Functional sets of parameters from walls are selected and blocks can be built.
A Data Driven Approach to the Online Monitoring of the Additive Manufacturing Process
Authors: Holtmann Jonas , Kiefel Denis , Neumann Stefan , Stoessel Rainer , Grosse Christian U.
Published: March 2021

Process monitoring in additive manufacturing (AM), i.e. in laser powder bed fusion (LPBF) of metal parts, has been identified as the crucial bottleneck in accelerating the AM industrialization process. To reduce the cost and time needed to produce and qualify an AM part, an online monitoring system of the manufacturing process is desirable. While the currently available systems capture a large amount of process data, they still lack the ability to interpret the acquired data adequately. In this work we present the first steps towards an automated evaluation of online monitoring data i.e. melt pool data. It is shown that a well-trained convolutional neural network (CNN) is able to detect artificially induced process deviations on the basis of melt pool characteristics.
Efficient Qualification Strategy of New Steel Alloys for Laser Powder Bed Fusion
Authors: Graf Gregor , Neuenfeldt Manuela , Müller Tobias , Fischer-Bühner Jörg , Beckers Daniel , Donisi Sven , Zanger Frederik , Schulze Volker
Published: March 2021

The requirements regarding the materials in use are steadily increasing in the AM market. As part of a GER-CAN research project (HiPTSLAM), the development of high-performance tool steels for AM is a promising topic regarding the acceptance of LPBF technology for functionally optimized die, forming and cutting tools. Therefore, a holistic development process to efficiently qualify new materials is introduced and its advantages are shown based on a case study with a maraging tool steel. The chemical composition of the steel was particularly developed for the use in the LPBF process to achieve beneficial performance properties. In the case study, effects of the LPBF parameters are evaluated on the material properties. Based on initial microstructure analysis, a promising set of parameters is used to build samples for heat treatment studies and mechanical characterization. By means of further investigations on the process interfaces, it will be possible to optimize the interaction of the whole LPBF process chain to increase the number of qualified materials with better performance properties.
Investigating the Reproducibility of the Wire Arc Additive Manufacturing Process
Authors: Halisch Christoph , Gaßmann Christof , Seefeld Thomas
Published: March 2021

Wire arc additive manufacturing (WAAM) of titanium parts shows promising potential for aerospace application due to its high deposition rates allowing a fast and economical production of large integral parts. However, due to the demands of aerospace industry an extensive qualification procedure is necessary to enable the parts as ready to fly. Nowadays, qualification for additive manufactured parts is a time-consuming process, so the advantages in additive manufacturing cannot be fully utilized. For this reason, a complete process qualification for WAAM would reduce the costs drastically in contrast to qualifying manufactured parts individually. As a first step the robustness and reproducibility of the energy reduced WAAM process was investigated. Thick-walled samples are manufactured layer by layer with an oscillating welding head motion. The mechanical properties of the samples are compared on an adequate statistical basis. Microstructural-and computer tomography analysis are conducted to comprehend shown interactions. The reproducibility is investigated in dependence of different heat treatment states, different directions of mechanical testing and two manufacturing systems of the same type.
The Effect of Bacterial Cellulose on The Thermo Hydro-Mechanical Treatment of Wood Veneer
Authors: Ananto Nugroho , Triastuti  , Iman Hidayat , Syahrial Anne Zulfia , Sandi Sufiandi
Published: March 2021

Wood is the largest source of cellulose in the nature however it has a low strength. In other hand, bacteria cellulose as a pure cellulose has a higher tensile strength than wood. Wood reinforced with bacterial cellulose was produced by self-assembly approach with veneer soak into the fermentation medium. The product of this research is hybrid veneer processed thermos-hydro-mechanical treatment. It has been used to give a change in its mechanical properties. This research analyzed mechanical tensile test, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. The result showed that bacteria cellulose had impact to increase tensile strength of veneer and improve the molecular strength between cellulose fibers. Hydrogen bonds were formed between veneer fibers and bacterial cellulose then those bonds stick together and resulted in strong adhesion.
Determination of Micromechanical Properties of Cementitious Materials with Self-Healing Agent
Authors: Prošek Zdeněk , Ryparová Pavla , Jíra Aleš , Bílý Petr , Tesárek Pavel
Published: March 2021

The paper deals with the determination of nano, microstructural, and micromechanical properties of cementitious materials surface with self-healing agent based on calcium carbonate precipitation (calcite). This was done by means of electron microscopy with elemental microanalysis and nanoindentation. These methods can define parameters of individual phases within cementitious materials, which are important for the development of micromechanical models. Bacillus pseudofirmus in combination with culture medium 235 was chosen as a self-healing agent. Our study provides information about micromechanical properties of crystals resulting from spontaneous crystallization from the culture medium and from crystallization caused by bacteria.
Mechanical Properties Evaluation of Render Mortars with Different Waterproof Additive Compositions
Authors: Rocha Joaquin Humberto Aquino , Galarza Fernando Palacios
Published: March 2021

Waterproof additives and bonding agent mixtures are commonly employed in the setting up of render mortars. This practice often shows beneficial results, enhancing the properties of the common mortars. Yet, the use of these additives does not seem to have a direct effect on the mechanical properties of the mortars. This study thus aims to evaluate the influence of the use of waterproof and adhesion additives on the mechanical properties of render mortars. Based on their chemical composition, three different types of mortar admixtures were evaluated, using fourfold additive-mortar weight ratios: 0%, 1.5%, 3%, and 5%. Compressive and flexural strength tests were conducted after 28 days. The results showed a negative impact on the mechanical properties of the mortars. The lowest flexural and compression strength values reported are 1.52 and 4.57 (MPa), respectively. However, all compressive and flexural strength values lied within the limit range recommended by the “Mortars applied on walls and ceilings” construction code (i.e., ABNT NBR 13281). It is compulsory to continue the experimental tests to determine render mortars mechanical properties with higher waterproof additive-mortar weight ratios since higher ratios might produce mortars with non-allowed mechanical properties.
Novel Direct Cladding of Magnesium and Aluminum Alloys Using a Horizontal Twin Roll Caster
Authors: Feng Geng Yan , Watari Hisaki , Suzuki Mayumi , Haga Toshio , Shimizu Toru
Published: March 2021

This study introduces the direct cladding of magnesium and aluminum alloys using a horizontal twin roll caster in one step. A horizontal twin roll caster can cast a Mg/Al clad strip with thickness exceeding 5mm at a roll speed of 8m/min in one step, which is difficult for a vertical twin roll caster. Therefore, it is possible to cast a thick clad strip with different melting point alloys using a horizontal twin roll caster at low speed. It is also possible to cast clad strips using as the overlay an alloy that has a higher melting point than that of the base strips. The thickness of the Mg/Al clad strip is 6.5mm, and the ratio of the Mg layer to the Al layer is 3:2. The surface of the clad strip is good, and there is no void between bonding interfaces. The mixing layer of the bonding interface is deeply related to the reduction rate. As the reduction rate increases, the mixing layer becomes more balanced and the thickness of the mixed layer decreases to 68μm. By observation of the interface of the cladded material, the mixed layer of the bonding interface is divided into two layers. It has been found the mixed layer near the Al layer has the highest hardness (up to 228HV), and the tensile shearing strength of the manufactured Mg/Al clad strip was 44MPa.
Residual Stress Analysis in Deep Rolling Process on Gas Tungsten Arc Weld of Stainless Steel AISI 316L
Authors: Thanakulwattana Warinthorn , Nakkiew Wasawat
Published: March 2021

Because of the general problem of the welding workpiece such as fatigue fracture caused by tensile residual stress lead to initial and propagation crack in the fusion zone. Thus, the mechanical surface treatment of deep rolling on Gas Tungsten Arc Welded (GTAW) surfaces of AISI 316L was studied. Deep rolling (DR) is a cold working process to induce compressive residual stress in the surface layer of the workpiece resulting in hardening deformation which increased surface hardness, and smooth surface that inhibit crack growth and improve fracture strength of materials. The present study focuses on compressive residual stress at the surface of stainless steel AISI 316L butt welded joint of GTAW. The three parameters of DR process were used; pressure 150 bar, rolling speed 400 mm/min, and step over 1.0 mm. The residual stresses analysis by X-ray diffraction with sin2Ψ method at 0, 5, 10, and 20 mm from the center of the welded bead. The results showed that the DR process on the welded of GTAW induce the minimum compressive residual stress-408.6 MPa and maximum-498.1 MPa in longitudinal direction. The results of transverse residual stress in minimum and maximum are 43.7 MPa and-34.8 MPa respectively. The FWHM of DR both longitudinal and transverse direction were increased in the same trend. Furthermore, the microhardness after DR treatment on workpiece surface layer higher than GTAW average 0.4 times.
Viscosity of Liquid Nanocrystalline Alloys
Authors: Tsepelev V.S. , Starodubtsev Yuri N. , Tsepeleva Nadezhda P.
Published: March 2021

Temperature dependences of the kinematic viscosity, density, and electrical resistivity of Fe72.5Cu1Nb2Mo1.5Si14B9and Fe84.5Cu0.6Nb0.5Si1.5B8.6P4C0.3multicomponent melts have been studied. We found different behavior of the temperature dependences of viscosity near the critical pointTk= 1760 K during heating, which is associated with different chemical compositions of the clusters in the melt. In the cooling stage, the activation energy of the viscous flow for these two melts is the same and equal to 43 kJ·mol-1. At a temperature of 1720 K, the relative free volume is 5.1 and 7.5 % of the total melt volume for Fe72.5Cu1Nb2Mo1.5Si14B9and Fe84.5Cu0.6Nb0.5Si1.5B8.6P4C0.3respectively. In the cooling stage, the electrical resistance of melt is higher than at the heating stage.
Inhibitory activity of stilbenes against filamentous fungi
Authors: Mattio Luce , Catinella Giorgia , Iriti Marcello , Vallone Lisa
Published: March 2021

Stilbenoids (resveratrol and its derivatives) are secondary metabolites produced by plants as defence mechanism to microbial infection. These compounds are known for their anti-inflammatory action and health benefits in preventing a wide range of disorders (e.g. cancer and cardiovascular diseases). However, their antimicrobial properties are less investigated. A series of 8 stilbenoid compounds were synthesized and their antifungal activity against 19 wild strains of filamentous fungi and yeasts (isolated from the environment and food) was tested in vitro. Using an agar diffusion assay, compounds were tested at the concentration of 100 μg/ml on filamentous fungi and yeasts at 104 CFU/ml. The results showed that tested derivatives possess moderate antifungal activity: in particular, monomeric stilbenoids 3’-hydroxy-pterostilbene and piceatannol, and dimeric stilbenoids (±)-trans-δ-viniferin and pallidol were active against mycotoxigenic fungi.
Influence of seasonality on the presence of okadaic acid associated with Dinophysis species: A four-year study in Sardinia (Italy)
Authors: Mudadu Alessandro G. , Bazzoni Anna Maria , Bazzardi Riccardo , Lorenzoni Giuseppa , Soro Barbara , Bardino Nadia , Arras Igor , Sanna Giovanna , Vodret Bruna , Virgilio Sebastiano
Published: March 2021

In Sardinia (Italy), bivalve molluscs production plays an important role in the trade balance. Diarrhoetic shellfish poisoning (DSP), an intoxication caused by the ingestion of bivalve molluscs that have accumulated high levels of Okadaic acid (OA), may represent a serious risk for the public health and a remarkable economic loss for the producers. Aim of this work was to improve knowledge about the repeatability of OA accumulation phenomena in various seasons trying to understand whether or not there was a trend. Also, the interaction between toxic algae and OA accumulation was examined. In this study, data of lipophilic toxins, water temperature and abundance of DSP-producing microalgal species were collected in a four-year period (2015–2018) in coastal production areas of Sardinia. Several episodes of OA positive values (>160 eq μgAO/Kg pe, Reg 853/04) were recorded during the study period in different production areas of Sardinia and in different seasons. A seasonal repeatability of OA accumulation in molluscs was observed in some production areas; moreover, different temporal gaps between the presence of toxic algae and OA accumulation were reported. Toxicity was observed almost exclusively in Mytilus galloprovincialis Lamark (99%), being this matrix the most abundant species bred in Sardinia.
Editor’s introduction: Qualitative research in the course of a pandemic
Authors: Balducci Lodovico
Published: March 2021

Not available.
Table of Contents Vol 2 (2020)
Authors: Office Editorial
Published: March 2021

No abstract available.
Table of Contents Vol 7 Issue 1 (2020)
Authors: Office Editorial
Published: March 2021

No abstract available.
The Impact of Khat (Catha edulis) on Hemodynamics of the Common Carotid Arteries in Regular Khat Chewers
Authors: Gameraddin Moawia , Abdalmalik Bushra A. , Ibrahim Mohamed
Published: March 2021

Background:

To evaluate the effect of chewing khat on the hemodynamics of the common carotid arteries (CCAs) using Doppler ultrasound imaging.

Methods:

This is a cross-sectional case–control study. Fifty volunteers who were chronic regular khat chewers were selected and compared with healthy nonkhat chewers. They were examined using Doppler imaging with a 7–10 MHz linear transducer. The resistivity index (RI), pulsatility index (PI), peak systolic velocity (PSV), and end-diastolic velocity of the CCAs were determined according to the standard protocol of carotid Doppler ultrasound.

Results:

The RI and PI of the right and left CCAs were significantly higher in khat chewers compared to controls (P < 0.001). The PSV of the right and left CCAs was considerably higher in khat chewers compared to controls (P < 0.001 and 0.04, respectively).

Conclusion:

The Doppler values of blood flow velocity, resistivity, and pulsatility were significantly higher in chronic regular khat chewers compared to nonkhat chewers. Khat is a significant contributory factor for increasing the hemodynamics of the CCAs.
Synergistic Interaction of Heavy Metal Salts with Hyperthermia or Ionizing Radiation
Authors: Tolkaeva Mariia , Mishra Kaushala Prasad , Evstratova Ekaterina , Petin Vladislav
Published: March 2021

Background:

One of the ways to enhance the effectiveness of radiation therapy or sterilization of objects of various origins is to use chemical agents in combination with hyperthermia and ionizing radiation. Some drugs commonly used in medicine include heavy metals. However, the study of their synergistic interaction with other agents is fragmentary. The purpose of this study was to establish a general pattern of synergistic interaction of heavy metal salts with hyperthermia or ionizing radiation.

Materials and Methods:

Bacterial and diploid yeast cells were used in the experiments. To quantify the synergistic effect, cell survival was determined after individual effects of heavy metal salts, hyperthermia, ionizing radiation, and their simultaneous action. The following heavy metal salts were used: lead iodide, potassium dichromate, cisplatin, and zinc sulfate.

Results:

For all analyzed cases, optimal conditions of interacting agents were observed under which the greatest synergistic effect was achieved.

Conclusion:

Comparison of the results obtained with previously published data indicates general patterns of synergistic effect display that are independent of acting agents, biological objects, and tests.
An Institutional Experience of Early Glottic Cancers Treated with Radiotherapy
Authors: Shah Aastha , Suryanarayan U
Published: March 2021

Introduction:

This retrospective study aimed at analyzing the recurrence rates in early glottic cancers (tumor, node, metastasis Stages I and II) treated at Gujarat Cancer and Research Institute (GCRI) from 2014 to 2018 by radiotherapy alone.

Materials and Methods:

The present study included 170 patients treated at GCRI from January 2014 to December 2018. One hundred and twenty-six patients were of stage T1N0, and rest 44 were of T2N0. Total radiotherapy dose received by them were 60 Gray in 30 fractions on linear accelerator with 6 MV photons without elective neck irradiation.

Results:

The mean duration of follow-up was 60 months. The local control (LC) rate was 93.65% in stage T1N0 stage and 84.1% in stage T2N0 glottic cancer. Out of the total 170 patients included in this study, 15 patients developed local recurrence which was biopsy proven, leading to overall local failure rate of 8.82%, and the mean time to recurrence as noted in our study was 9.1 months. Ultimate LC rate by radiotherapy alone was 91.2%.

Conclusion:

Radiotherapy provides better LC along with the advantage of organ preservation in T1N0 and T2N0 glottic cancer, and the local failure can be salvaged by surgery.
Pembrolizumab-Induced Myasthenia Gravis in a Patient with Thymic Carcinoma
Authors: Aykaç Seyma Çiftçi , Erkılınç Büşra , Uludağ Burhanetti
Published: March 2021

Pembrolizumab is an immune checkpoint inhibitor. Most cases of myasthenia gravis (MG) reported with the use of immune checkpoint inhibitors have been in melanomas, and small and non-small cell lung carcinoma, but there are no reported cases in thymic epithelial carcinoma. A 57-year-old male with thymic carcinoma presented with symptoms of diplopia, drooping eyelids, and difficulty in talking and swallowing after a second dose of pembrolizumab. Contrast-enhanced brain magnetic resonance imaging, laboratory tests, and electroneuromyography were normal. Single-fiber electromyography showed increased jitter (six muscle fibers were collected, range of jitter 29–140 μs, mean 75 μs; normal <35 μs) in bilateral orbicularis oculi muscles supporting MG. Serum screening showed no any positivity for acetylcholine receptor and muscle-specific tyrosine kinase autoantibodies. The patient died of bulbar dysfunction related to aspiration pneumonia despite receiving intravenous immunoglobulin and methylprednisolone therapy. Physicians should be alert to possible exacerbations of autoimmune diseases and associated risks, especially during treatment with checkpoint inhibitors in thymic malignancy.
Reliability and Validity of the Turkish Version of the Morningness – Eveningness Questionnaire
Authors: Özdalyan Firat , Tütüncü Özkan , Gümüş Hikmet , Açıkgöz Osman
Published: March 2021

Background:

People are divided into different chronotypes in relation to their circadian rhythm features. The Morningness–Eveningness Questionnaire (MEQ), developed by Horne and Östberg, was the first and is the most used questionnaire for determining the chronotype of people. The reliability and validity of MEQ were tested in this study due to some deficiencies and inconsistencies in previous reliability and validity studies for the Turkish versions of MEQ and deficiencies regarding the validity and reliability of other versions of MEQ.

Subjects and Methods:

MEQ was translated into Turkish based on the opinions of five academics who were experts in their respective fields and the suitability and content validity of the questionnaire were ensured. The Turkish MEQ was administered to 419 undergraduate students aged 18–34 years. Robust minimum rank factor analysis (MRFA) was used to reveal the construct validity of the questionnaire.

Results:

As a result of the analyses, the questionnaire was examined in three factors. None of the items were excluded from the study and all items were collected under three factors. The explained total variance value was 42.7%, and the factors explained 64% of common (shared) variance in MRFA. According to the reliability analysis, Cronbach's alpha value for the MEQ Turkish version was satisfactory for the overall questionnaire (0.765).

Conclusions:

The MEQ version developed in this study is more valid and reliable compared with other versions. However, these results support that a more detailed instrument for morningness and eveningness can be developed.
MScanFit Motor Unit Number Estimation
Authors: Tankisi Hatice
Published: March 2021

Motor unit number estimation (MUNE) methods have been found to be better suited than any other electrophysiological test to study the degree and time course of lower motor unit loss. However, MUNE methods have not yet been implemented in clinics and research. This may be because an ideal method has not been developed yet. This review aims to give an overview of the strengths and limitations of the existing MUNE methods, why a new method was necessary and how the novel MScanFit MUNE can overcome some of the limitations that the other methods had. In the end, the existing literature MScanFit applied has been summarised.