Finite groups in Axiomatic Index Number Theory

In this paper we adopt Group Theory to investigate the symmetry and invariance properties of price index numbers. An alternative treatment is given to the study of the reversibilty axioms, that clarifies their meaning and allows for a conceptual unification of this topic, within the framework of Axiomatic Index Number Theory.Price index, Axiomatic Index Number Theory, Basis antithesis, Factor antithesis, Group Theory

Il Paliotto di Teramo di Nicola da Guardiagrele: funzione, iconografia, stile, restauri.

La tesi si propone di affrontare alcune delle molteplici problematiche inerenti all'opera nota con il nome di “Paliotto di Teramo” o anche “parato di San Berardo”; il manufatto è conservato infatti all'interno della cattedrale teramana che proprio a San Berardo è dedicata. L'opera fu commissionata all'orafo abruzzese Nicola da Guardiagrele (nato fine secolo XIV - morto poco prima del 1462), che nei quindici anni fra il 1433 e il 1448 lavorò alla sua realizzazione. L' antependium, una vera e propria tavola mobile delle dimensioni di 117x234 cm, si pone come un'opera molto complessa dal punto di vista compositivo, iconografico, decorativo e della tecnica di esecuzione. Brevemente dirò che è fondamentalmente realizzata per mezzo di lamine d'argento, montate su un supporto ligneo e sbalzate, parzialmente fuse, cesellate, puntinate, incise e dorate, più l'inserimento di componenti a smalto distinguibili invece per l'utilizzo della tecnica dell'émail translucide de bassetaille e dello smalto champlevé opaco, traslucido e filigranato, tutto su argento. Il paliotto è inoltre strutturato in trentacinque formelle di forma ottagonale (quadrati con angoli smussati) entro le quali si sviluppa la gran parte del programma iconografico dell'opera; vi sono così venticinque storie della vita di Cristo, nove figure singole (i quattro Evangelisti, i Quattro Padri della Chiesa e un Cristo Benedicente posto al centro del paliotto) ed una storia apparentemente fuori contesto, il San Francesco che riceve le stimmate. A ciò si devono aggiungere inoltre le ventidue figure singole, fra Apostoli e Profeti, più un Cristo e la Madonna con il Bambino, presenti nelle placchette a smalto traslucido su basso rilievo prima menzionato. All'interno di questo lavoro di tesi si è cercato di concentrarsi sopratutto su quegli aspetti in un certo qual modo trascurati finora dalla critica; l'opera, che ha attratto fin dalla fine del secolo XIX l'attenzione di molti studiosi, è stata prevalentemente messa a fuoco in relazione ad alcune problematiche fisse: il rapporto fra l'artista e l'opera del Ghiberti (da cui gran parte dei modelli iconografici sono tratti), la possibilità o meno di un viaggio a Firenze, l'individuazione di più maestri di bottega che nel paliotto hanno lavorato, oltre ad alcune più recenti ipotesi sulla paternità degli smalti figurati; sostanzialmente dunque problemi iconografici e stilistici. Fra i problemi di ordine nuovo che ci si propone di trattare in questo lavoro possiamo indicare in primis quello inerente alla struttura geometrica del paliotto, cioè l'articolazione e la distribuzione delle iconografie. Le radici di questo schema, tenendo presente la particolare posizione geografica e le influenze a cui la regione abruzzese era da sempre sottoposta, sono state quindi ricercate in area adriatico-veneziana, associata però ad una contaminazione coi modelli elaborati nelle botteghe di codici miniati che lavoravano per la casa reale angioina ed il suo stretto entourage. Segue a ciò la trattazione del problema iconografico, in particolare la ricerca di altri modelli di riferimento, al di là del modello ghibertiano, utilizzati dall'orafo guardiese. La ricerche svolte in questo senso hanno finora rivelato un inaspettato riferimento al mondo giottesco; tale riferimento, riscontrabile non solo nell'opera teramana ma almeno in un'altra opera del periodo giovanile dell'orafo, cosa per cui si porrebbe ipotizzare una costante culturale per gran parte del percorso artistico di Nicola. Al di là di questi aspetti più strettamente storico-artistici si è cercato di relazionare le scelte compositive, cioè di organizzazione dei vari episodi narrativi e delle varie figure singole presenti nel paliotto, in relazione a quegli aspetti teologico-devozionali che, caratteristici del primo Quattrocento, affondavano le radici nella letteratura e nelle speculazioni mistiche dei due secoli precedenti. Dalle Meditationes Vitae Christi di Giovanni de Caulibus alle prediche di San Bernardino da Siena, solo per dirne alcune, si percorre la strada che aiuta a comprendere sia l'insistenza, nel Paliotto di Teramo, sul ciclo della Passione, sia la presenza del San Francesco stigmatizzato a fine testo. A conclusione del lavoro si inserirà una sezione dedicata alla storia conservativa del paliotto ed incentrata in modo particolare su un restauro avvenuto nel 1748 e documentato sul paliotto grazie ad una iscrizione sulla cornice argentea ad arabeschi di cui il paliotto è dotato. Le informazioni per lo studio di tale intervento hanno richiesto una ricerca nell'Archivio Diocesano di Teramo, durante la quale sono stati reperiti due documenti inediti inerenti a tele restauro settecentesco, molto utili alla precisazione di alcuni aspetti finora rimasti poco chiari

Cellular and molecular mediators of bone metastatic lesions

Bone is the preferential site of metastasis for breast and prostate tumor. Cancer cells establish a tight relationship with the host tissue, secreting factors that stimulate or inhibit bone cells, receiving signals generated from the bone remodeling activity, and displaying some features of bone cells. This interplay between tumor and bone cells alters the physiological bone remodeling, leading to the generation of a vicious cycle that promotes bone metastasis growth. To prevent the skeletal-related events (SRE) associated with bone metastasis, approaches to inhibit osteoclast bone resorption are reported. The bisphosphonates and Denosumab are currently used in the treatment of patients affected by bone lesions. They act to prevent or counteract the SRE, including pathologic fractures, spinal cord compression, and pain associated with bone metastasis. However, their primary effects on tumor cells still remain controversial. In this review, a description of the mechanisms leading to the onset of bone metastasis and clinical approaches to treat them are described

3D scanning, modelling and printing of ultra-thin nacreous shells from Jericho: a case study of small finds documentation in archaeology

This paper springs out from a collaborative project jointly carried out by the FabLab Saperi&Co and the Museum of Near East, Egypt and Mediterranean of Sapienza University of Rome focused at producing replicas of ultra-thin archeological finds with a sub-millimetric precision. The main technological challenge of this project was to produce models through 3D optical scanning (photogrammetry) and to print faithful replicas with additive manufacturing. The objects chosen for the trial were five extremely fragile and ultra-thin nacreous shells retrieved in Tell es-Sultan/ancient Jericho by the Italian-Palestinian Expedition in spring 2017, temporarily on exhibit in the Museum. The experiment proved to be successful, and the scanning, modeling and printing of the shells also allowed some observations on their possible uses in research and museum activities

On the Relationships among Latent Variables and Residuals in PLS Path Modeling: the Formative-Reflective Scheme

A new approach for the estimation and the validation of a Structural Equation Model with a formative-reflective scheme is presented. The basis of the paper is a proposal for overcoming a potential deficiency of PLS Path Modeling. In the PLS approach the reflective scheme assumed for the endogenous latent variables is inverted; moreover, the model errors are not explicitly taken into account for the estimation of the endogenous latent variables. The proposed approach utilizes all the relevant information in the formative manifest variables providing solutions which respect the causal structure of the model. The estimation procedure is based on the optimization of the redundancy criterion. The new approach, entitled Redundancy Analysis approach to Path Modeling is compared with both traditional PLS Path Modeling and LISREL methodology, on the basis of real and simulated data.Latent Variables, Partial Least Squares, PLS Path Modeling, Redundancy Analysis, LISREL Model

MicroRNAs in melanoma development and resistance to target therapy

microRNAs constitute a complex class of pleiotropic post-transcriptional regulators of gene expression involved in the control of several physiologic and pathologic processes. Their mechanism of action is primarily based on the imperfect matching of a seed region located at the 5' end of a 21-23 nt sequence with a partially complementary sequence located in the 3' untranslated region of target mRNAs. This leads to inhibition of mRNA translation and eventually to its degradation. Individual miRNAs are capable of binding to several mRNAs and several miRNAs are capable of influencing the function of the same mRNAs. In recent years networks of miRNAs are emerging as capable of controlling key signaling pathways responsible for the growth and propagation of cancer cells. Furthermore several examples have been provided which highlight the involvement of miRNAs in the development of resistance to targeted drug therapies. In this review we provide an updated overview of the role of miRNAs in the development of melanoma and the identification of the main downstream pathways controlled by these miRNAs. Furthermore we discuss a group of miRNAs capable to influence through their respective up- or down-modulation the development of resistance to BRAF and MEK inhibitors

Enhanced self-administration of the CB1 receptor agonist WIN55,212-2 in olfactory bulbectomized rats: evaluation of possible serotonergic and dopaminergic underlying mechanisms

Depression has been associated with drug consumption, including heavy or problematic cannabis use. According to an animal model of depression and substance use disorder comorbidity, we combined the olfactory bulbectomy (OBX) model of depression with intravenous drug self-administration procedure to verify whether depressive-like rats displayed altered voluntary intake of the CB1 receptor agonist WIN55,212-2 (WIN, 12.5 μg/kg/infusion). To this aim, olfactory-bulbectomized (OBX) and sham-operated (SHAM) Lister Hooded rats were allowed to self-administer WIN by lever-pressing under a continuous [fixed ratio 1 (FR-1)] schedule of reinforcement in 2 h daily sessions. Data showed that both OBX and SHAM rats developed stable WIN intake; yet, responses in OBX were constantly higher than in SHAM rats soon after the first week of training. In addition, OBX rats took significantly longer to extinguish the drug-seeking behavior after vehicle substitution. Acute pre-treatment with serotonin 5HT1B receptor agonist, CGS-12066B (2.5-10 mg/kg), did not significantly modify WIN intake in OBX and SHAM Lister Hooded rats. Furthermore, acute pre-treatment with CGS-12066B (10 and 15 mg/kg) did not alter responses in parallel groups of OBX and SHAM Sprague Dawley rats self-administering methamphetamine under higher (FR-2) reinforcement schedule with nose-poking as operandum. Finally, dopamine levels in the nucleus accumbens (NAc) of OBX rats did not increase in response to a WIN challenge, as in SHAM rats, indicating a dopaminergic dysfunction in bulbectomized rats. Altogether, our findings suggest that a depressive-like state may alter cannabinoid CB1 receptor agonist-induced brain reward function and that a dopaminergic rather than a 5-HT1B mechanism is likely to underlie enhanced WIN self-administration in OBX rats

La recherche suisse en éducation interculturelle. Panorama des recherches empiriques réalisées entre 1993 et 2006: Rapport final.

Le projet de réaliser un recensement des études suisses faites dans le domaine de l’éducation interculturelle durant ces 15 dernières années environ est né d’une volonté de réanimation du groupe de travail « Approches interculturelles » de la SSRE qui était inactif depuis plusieurs années. Avec ce recensement, le groupe de travail de la SSRE – qui s’est entre-temps nommé « Éducation interculturelle » – apporte une nouvelle pierre à la construction du champ de la recherche en éducation interculturelle en Suisse. Ce recensement fait suite à trois moments-clé de la vie de ce groupe de travail, qui avaient à chaque fois permis aux chercheurs1 suisses de faire le point sur leurs travaux : la parution en 1981 du livre collectif Etre migrant I (Gretler, Perret-Clermont, & Poglia, 1981), suivie en 1995 par le 2e volume, Être migrant II (Poglia, Perret-Clermont, Gretler, & Dasen, 1995), ainsi que la tenue à Berne en 1993 du colloque Inter-93 (Allemann-Ghionda, 1994)

Is there a potential of misuse for Magnolia officinalis compounds/metabolites?

© 2017 John Wiley & Sons, Ltd.Objective: Magnolia bark contains magnolol, metabolized to tetrahydromagnolol and honokiol, with both GABA-ergic/cannabimimetic activities, hence of possible attraction to vulnerable individuals/recreational misusers. Methods: A literature review, assessment of related anecdotal online Magnolia misuse's reports and an overview of Magnolia products' online acquisition possibilities has been here described. Results: No peer-reviewed papers about Magnolia abuse/misuse/dependence/addiction were identified. Conversely, from a range of websites emerged potentially 3 groups of Magnolia misusers: (a) subjects with a psychiatric history already treated with benzodiazepines, being attracted to Magnolia bark as a “natural sedative”; (b) polydrug misusers, ingesting Magnolia with a range of other herbs/plants, attracted by the GABA-ergic/cannabimimetic activities; (c) subjects naive to the misusing drugs' scenario, perceiving Magnolia as a natural dietary supplement/weight-control compound. Conclusions: To the best of our knowledge, this is the first paper commenting on the possible Magnolia derivatives' potential of misuse. Magnolia's recent increase in popularity, mainly as a sedative, may be arguably due to its peculiar pharmacological properties/acceptable affordability levels/virtually worldwide favorable legal status and customers' attraction to a product being perceived as “natural” and hence somehow “safe.” Future/potent/synthetic magnolol and honokiol structural analogues could however contribute to increasing the number of synthetic GABA-ergic/cannabimimetic misusing compounds.Peer reviewe

La recherche empirique en education interculturelle en Suisse: comparaison entre la Suisse francophone et la Suisse germanophone

C’est aux chercheurs en éducation interculturelle et à leurs travaux que s’est intéressée l’étude rapportée ici : quelles sont les thématiques traitées, auprès de quelles populations, avec quelles méthodes? Le champ de l’éducation interculturelle s’est maintenant bien établi, institutionnellement dans des cursus de formation de plus en plus nombreux, mais aussi dans la communauté scientifique grâce par exemple à l’IAIE (International Association for Intercultural Education). En Suisse, un groupe de travail dédié à l’éducation interculturelle existe depuis le début des années 1980 au sein de la Société suisse de recherche en éducation. C’est de ce groupe de travail qu’émane la présente étude