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The fragmentary statue of the famous general Neshor called Psamtek-Menekhib, hailing from the city of Mendes, has been an object of interest for a generation of Egyptologists, in particular for its hieroglyphic text. Published and cited many times since its discovery, the statue was first identified in Cairo in 1947. After a long journey through some European private collections and auctions, it was acquired by the Museo Egizio in Turin in 2002. Its condition changed significantly between 1947 and 2002: the lower part of the original back-pillar disappeared and a modern face was added. This article traces Neshor’s long journey from Cairo to Turin, shedding light on the practices of the Egyptian antiquities market in Egypt and abroad during the 20th century, and on the role played in it by Egyptologists such as those who documented the statue. الملخص التمثال المجزأ للجنرال الشهير نيشور والمسمى أيضاً "بْسامتِك-مِنخيب"، أصله من مدينة مينديز، و قد استقطب اهتمام جيلٌ كامل من علماء المصريات، وخاصة بسبب النص الهيروغليفي المنقوش عليه. منذ لحظة اكتشاف التمثال تم النشر والحديث عنه عدّة مرّات، تم الكشف عن هويته لأول مرة في القاهرة عام 1947. المتحف المصري في تورينو حصل عليه في عام 2002 بعد رحلة طويلة انتقل من خلالها ما بين العديد من المجموعات والمزادات الأوروبية الخاصة. لقد تغيّرت معالم التمثال تغيراً ملحوظاً ما بين عامي 1947 و 2002: اختفى الجزء السفلي من العمود الخلفي الأصلي وأضيف عوضاً عنه وجه حديث. يتابع هذا المقال مسيرة الرحلة الطويلة لتمثال نيشور من القاهرة إلى تورينو، ويُسلّط الضوء على فعّاليات سوق الآثار المصرية في داخل مصر وخارجها خلال القرن العشرين، وعلى الدَور الذي لعبه علماء المصريات وبالتحديد أولئك الذين وثّقوا وكتبوا عن التمثال.

A Concept Map provides a graphical, hierarchical, representation of a domain of knowledge, and can be used by teachers to define and organize the content of a course. The use of existing concept maps, possibly implemented by means of tested and suitable learning material, can be of great help for the teacher, while defining her/his own concept map. In this context, being able to establish the similarity between two concept maps is a significant asset, allowing to limit the analysis of other maps, and focus on those that can be of actual help for the teacher. This is true in a special way if the measure is computed 'according to one among many possible pedagogical criteria of similarity'. We are working on the definition of measures entailing similarity based on different pedagogical criteria. In this paper, we meet the problem of experimenting such with measures, and comparing them with baseline measures, while investigating the effectiveness of a new measure. To support this kind of analysis we propose here a web-based system. We show the characteristics of the system, and use it to compare the behaviour of three measures of similarity: the pre-requisite measure (also presented) computes the similarity of two maps with respect to a particular pedagogical aspect. The other two measures are used as a baseline. We conclude that the system has shown its usefulness and can be used for more extensive analysis of other measures.

Nowadays a significant portion of the general public cannot fully experience an archaeological exhibition due to the presence of several sensory barriers. In this work, I will focus on how technology can help to overcome one of these barriers: blindness. This goal can be achieved (by) creating touchable copies of finds where depicted decorations or inscriptions can be perceived through tactile experience. The process to build such (enriched) copies is structured in several steps: it starts from photogrammetry and ends with 3D printing. The aim of this process is not only to create a copy but also to provide a deeper understanding of the object and widen our experience of how we look at and read inscriptions. This is why the realization of such copies may be useful for a wider public, for example, children that will be afforded the chance to touch the ancient objects, thus understanding them better. Some relevant issues that affect the quality of the results are to be considered and require further analysis, such as the choice of the object, with respect to the complexity of decoration, and the adequate material for printing. The process has been tested on a figured vessel preserved in the Archaeological Museum of Paestum’s storage. The produced copy with decoration in relief has been evaluated and approved by two members of the Italian Union of the Blind and Partially Sighted People (a blind woman and a visually impaired man).

The public availability of datasets of teaching resources is an issue for the design, development and evaluation of Information Retrieval and Recommender Systems in Technology Enhanced Learning. Recently, the Dataset of Joint Educational Entities (DAJEE) has provided the community with a very exhaustive collection of resources coming from Massive Open Online Courses. This work proposes a representation of the DAJEE dataset according to Linked Data principles, interlinking the large amount of resources in DAJEE with the Web of Data. The transcript of the educational resources in DAJEE have been annotated through a Named Entity Recognition tool in order to create interlinks with the DBpedia entities. The DBpedia knowledge base provides additional information related to categories, that can be exploited to infer new knowledge and support reasoning processes.

Concept maps are at the base of teaching activity and they are widely used in the process of creating courses. In the perspective of reusing learning materials, we could do the same (reuse) also with concept maps. Unfortunately concepts maps are hard to compare in an educational setting, as most of the algorithms applied to this task work mainly on structural similarity, and may take into limited account pedagogical issues. In this work, we consider some measures that take into consideration both structural and didactic aspects of the concept maps, such as the prerequisite relation and the commonality of concepts, and present a framework that allows teacher to draw and/or compare her concept map with maps proposed by other teachers, in order to highlight common pedagogical aspects.

When teachers are surfing the Web to search suitable learning material for their courses it would be very important that web resources were characterized to restrict the scope of the search. Hence, it arises the need of finding characterizing properties for learning materials. This paper proposes an initial reflection on this issue. We exploit the huge potential of the MOOC, in particular Coursera, to discover new educational information that might characterize material of MOOCs. This goal is achieved by means of data mining techniques. Two types of features about resources have been discovered: teaching context and resource attributes. The resulting knowledge can be very helpful for a more accurate recommendation of resources to the particular teaching context of an instructor, as well as improving the creation and arrangement of learning activities.

International audience; The stability of the recirculation bubble behind a smoothed backward-facing step is numerically computed. Destabilization occurs first through a stationary three-dimensional mode. Analysis of the direct global mode shows that the instability corresponds to a deformation of the recirculation bubble in which streamwise vortices induce low- and high-speed streaks as in the classical lift-up mechanism. Formulation of the adjoint problem and computation of the adjoint global mode show that both the lift-up mechanism associated with the transport of the base flow by the perturbation and the convective non-normality associated with the transport of the perturbation by the base flow explain the properties of the flow. The lift-up non-normality differentiates the direct and adjoint modes by their component: the direct is dominated by the streamwise component and the adjoint by the cross-stream component. The convective non-normality results in a different localization of the direct and adjoint global modes, respectively downstream and upstream. The implications of these properties for the control problem are considered. Passive control, to be most efficient, should modify the flow inside the recirculation bubble where direct and adjoint global modes overlap, whereas active control, by for example blowing and suction at the wall, should be placed just upstream of the separation point where the pressure of the adjoint global mode is maximum. © 2009 Cambridge University Press.

In this work we address the problem of automatically finding prerequisite relations among learning materials in order to help instructional designers to speed up the course building process. Ours is a data-driven approach, where a (machine) learner is trained to classify predecessor/successor relationships, given two didactic materials in a textual form. As the training set we use the learning materials extracted from Coursera. A first evaluation shows promising results.

Technology Enhanced Learning (TEL) largely focuses on the retrieval and reuse of educational resources from Web platforms like Coursera. Unfortunately, Coursera does not provide educational metadata of its content. To overcome this limitation, this study proposes a data mining approach for discovering Teaching Contexts (TC) where resources have been delivered in. Such TCs can facilitate the retrieval of resources for the teaching preferences and requirements of teachers.

Nowadays, teachers tend to build their own didactic local repository composed by learning objects retrieved from web repositories or, in most cases, by self-made didactic material. In this way they do not share their teaching experience, loosing a precious shortcut to a fast professional update and to an improvement of their teaching activity. In this paper we address the problem of helping teachers to retrieve didactic material from a repository through a didactic social network where teachers with similar Teaching Styles, can help each other in retrieving educational material. To this aim a teaching-styles based social network is built following the Grasha TS paradigm. We present a first evaluation of the network embedded in a web application.

Building a new course is a complex task for teachers: the entire process requires different steps, starting with the concept map building and ending with the delivery of the learning objects to students through a learning management system. Teachers have to spend a lot of time to build or to retrieve the right learning material from local databases or from specialized repositories on the web. Consequently, having a system supporting this phase is a very important challenge, considering that each teacher expresses her own pedagogy as well. Here we propose a novel Teacher Model that helps teachers to build new courses effectively. The model is based both on a didactic semantic network containing concepts and learning material and on Teaching Styles as proposed in the literature by Grasha. This framework gives teachers the possibility to share their teaching experience as well. A first experimentation of the system gives positive results.

When addressing multi-domain/multi-physics problems, the correct exchange of mathematical information at subdomain interfaces is crucial. In this paper, such transfer is analyzed in the particular framework of a fluid-structure interaction (FSI) problem. A genuine FEM–FEM formulation is considered firstly, followed by a mixed FVM–FEM formulation. In both cases, we focus on two critical issues: how to interpolate numerical quantities at the interface, and how to achieve the property of conservation of energy transfer. In the second part of this work, we analyze the use of radial basis functions (RBF) to handle both mesh motion and interpolation of numerical variables over non-matching interface grids. Different kinds of radial basis functions are considered and numerical tests comparing their performances in terms of accuracy and stability are presented and discussed.

Purpose The reverse posterior interosseous artery flap has several advantages, not sacrificing any major blood vessel, but its relatively short pedicle limits the use to cover defects up to the metacarpophalangeal joint. Our purpose is to demonstrate that the ligature of the anterior interosseous artery (AIA), proximal to the communicating branch with the posterior interosseous artery, leads to an improved flap rotation arch, preserving both vascular sources. Methods Sixteen fresh cadavers with latex perfusion were analyzed before and after our technique of elongation, and the so-obtained measures were standardized in "percentage of elongation of the pedicle." Eight patient with the loss of substance at the dorsal aspect of the hand have been treated with this technique, and results were evaluated in terms of flap survival and complication rates. Results The medium length of the pedicle in the normal flap was 10.8 cm, and after the section of the AIA, the medium length of the pedicle was 13.6 cm with a medium increase of 2.8 cm. It means a medium increase of 24% of the length of the pedicle. In all patients treated, full coverage of the defect was obtained, and we did not experience major complications. Conclusions This anatomical study supported by our clinical experience demonstrates that the use of the variant described above permits to reach more distal part of the hand without being afraid to stretch the pedicle because of the connection with the anastomotic arcades of the AIA at the wrist reducing the risk of ischemia of the flap.

BACKGROUND: Facial lipoatrophy is a stigmatizing hallmark of HIV. The injection of facial fillers has an essential role in the treatment of this condition. The objective of our study was to verify the safety and efficacy of a new formulation of high-density hyaluronic acid for the injectable treatment of HIV-related facial lipoatrophy.METHODS: We treated with high-density hyaluronic acid injections HIV patients affected by moderate to severe facial lipoatrophy and evaluated them at last follow-up, at a minimum of 36 weeks. Physician-related outcomes included pre-and post-treatment ultrasound measurement of the soft-tissue thickness of the cheeks and qualitative assessment of aesthetic results by means of the Global Aesthetic Improvement Scale using pre- and post-treatment photos of the patients. Patient satisfaction outcomes were evaluated with the VAS-face scale and Freiburg test.RESULTS: Fifty-four patients were studied. The median number of treatment sessions was 3 and the median length of treatment was 5.5 months. The thickness of the soft tissues of the cheek increased significantly from 9.45 to 13.12 mm (p < 0.0001). On the basis of the Global Aesthetic Improvement Scale, 87.5% of the patients were judged as "much improved" or "improved." Patient satisfaction at 1 year from the end of treatment was proven (VAS-face: 77.9; Freiburg questionnaire: 93.6% of patients were satisfied or very satisfied). Complications were limited to mild redness and swelling in the early postoperative period.CONCLUSION: Long-term improvement of facial contour and excellent patient satisfaction, in the absence of severe side effects, were obtained by the injection of high-density hyaluronic acid (STYLAGE(®) XL) in HIV patients with facial lipoatrophy.

International audience; Experimental studies of laminar plumes descending under gravity into stably stratified environments have shown the existence of a critical injection velocity beyond which the plume exhibits a bifurcation to a coiling instability in three dimensions or a sinuous instability in a Hele-Shaw flow. In addition, flow visualization has shown that, prior to the onset of the instability, a stable base flow is established in which the plume penetrates to a depth significantly smaller than the neutral buoyancy depth. Moreover, the fresh water that is viscously entrained by the plume recirculates within a 'conduit' whose boundary with the background stratification appears sharp. Beyond the bifurcation, the buckling plume takes the form of a travelling wave of varying amplitude, confined within the conduit, which disappears at the penetration depth. To determine the mechanisms underlying these complex phenomena, which take place at a strikingly low Reynolds number but a high Schmidt number, we study here a two-dimensional arrangement, as it is perhaps the simplest system which possesses all the key experimental features. Through a combination of numerical and analytical approaches, a scaling law is found for the plume's penetration depth within the base flow (i.e. the flow where the instability is either absent or artificially suppressed), and the horizontal cross-stream velocity and concentration profile outside the plume are determined from an asymptotic analysis of a simplified model. Direct numerical simulations show that, with increasing flow rate, a sinuous global mode is destabilized giving rise to the self-sustained oscillations as in the experiment. The sinuous instability is shown to be a consequence of the baroclinic generation of vorticity, due to the strong horizontal gradients at the edge of the conduit, a mechanism that is relevant even at very low Reynolds numbers. Despite the strength of this instability, the penetration depth is not significantly affected by it, instead being determined by the properties of the plume in the vicinity of the source. This scenario is confirmed by a local stability analysis. A finite region of local absolute instability is found near the source for sinuous modes prior to the onset of the global instability. Sufficiently far from the source the flow is locally stable. Near the onset of the global instability, varicose modes are also found to be locally, but only convectively, unstable.

Search engines and recommender system take advantage of user queries, characteristics, preferences or perceived needs for filtering results. In contexts such as education, considering the purpose of a resource is also fundamental. A document not suitable for learning, although well related to the query, should never be recommended to a student. However, users are currently obliged to spend additional time and effort for matching the machine-filtered results to their purpose. This paper presents a method for automatically filtering web-pages according to their educational usefulness. Our ground truth is a dataset where items are web-pages classified as relevant for education or not. Then, we present a new feature selection method for lowering the number of attributes of the items. We build a committee of feature selection methods, but do not use it as an ensemble. A comprehensive evaluation of our approach against current practices in feature selection and feature reduction demonstrates that our proposal 1) enables state-of-the-art classifiers to perform a significantly faster, yet very accurate, automatic filtering of educational resources, and 2) such filtering meaningfully considers the usefulness of the resource for educational tasks.

The numerical simulation of free-surface flows around sailing boats is a complex topic that addresses multiple mathematical tasks: the correct study of the flow field around a rigid hull, the numerical simulation of the hull dynamics, the deformation of the sails and appendages under transient external conditions like gusts of wind or wave patterns and, overall, the coupling among all these components. In this paper, we present some recent advances that have been achieved in different research topics related to yacht design and performance prediction. In particular, we describe the numerical algorithms that have been developped in the framework of open-source libraries for the simulation of free-surface hydrodynamics and boat dynamics, as well as for the analysis of the fluid-structure interaction between wind and sails. Moreover, an algorithm for shape optimization, based on the solution of the adjoint problem and combined with the Free Form Deformation (FFD) method for the shape parameterization and mesh motion, is presented and discussed. Theoretical and methodological aspects are described, and the first preliminary results are reported.