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Experimenting Generalized Procrustes Analysis on a corpus of scenes carved on Mesopotamian cylinder seals and encoded in a textual data set
Get PDFIn a recently published study, a textual dataset encoding a group of scenes depicted on Mesopotamian cylinder seals from the third millennium was submitted to Procrustes Analysis, considering Correspondence Analysis variations due to progressive reductions of the forms involved. The results seemed to indicate that a slight reduction in the number of forms used to describe the raw data would improve the Correspondence Analysis results. Indeed, the actual impact of each reduction on the outcome of the analyses could not be adequately identified if the forms were not considered as elements forming segments, i.e., sub-images of the scenes. In this paper, the results of the same methodology are presented, this time applied to repeated segments within the same dataset, i.e., sequences of textual forms that may describe sub-images of the described scenes. The comparison between the progressive reductions of repeated segments showed relevant differences between small (around 10 of the rarest segments) and large reductions. Indeed, the latter may undermine a consistent interpretation of the different finding sites, yet well represented keeping 90 of segments. Moreover, a reduction performed by hand and not on the frequency of occurrences provided better results
La coesistenza tra umani e animali come sfida etica, politica e di governance
Get PDFIl tema della coesistenza tra le diverse forme di vita, umana e animale, è certamente uno di quelli che stimola la discussione tra punti di vista diversi, a volte simili, altre addirittura opposti tra loro. Si tratta di una questione molto sentita nella comunità cittadina, in particolare a Roma, una delle città europee più ricche in termini di biodiversità, come è stato evidenziato dai numerosi studi sulla fauna urbana della Capitale degli ultimi decenni. Allo stesso tempo, un tema di grande attualità, spesso salito agli onori della cronaca e proprio per questo, come sovente accade, oggetto di visioni oscillanti tra l'eccessiva semplificazione e l'estremizzazione dei concetti
Agricoltori, animali domestici e animali selvatici hanno l’interesse comune di vivere in equilibrio
Get PDFIl documento del Comitato bioetico per la Veterinaria e l'Agroalimentare crea l'occasione per affrontare una questione sempre più calda e ormai quasi quotidianamente presente nell'informazione. Ormai il coinvolgimento dei centri abitati non solo delle zone rurali è, come era prevedibile, frequente, quindi non si tratta più di un problema del solo mondo degli agricoltori e allevatori
Qanat, una tecnologia del passato, una risorsa per il futuro: riferimenti storici, aspetti socio-economici e repertorio tipologico
Get PDFThe lack of surface water and a high potential for evapotranspiration are the climatic and hydrological characteristics of the arid and semi-arid Middle East regions. In foothills regions the groundwater, often supplied by partially buried alluvial fan systems, has been intercepted and conveyed through the creation of a highly efficient supply system known as ‘qanat’, ‘karez’ or ‘foggara’. This ancient hydraulic technology spread on a large scale since the 6th century BCE, during the rise and development of the Persian Empire. It consists in the excavation of a series of vertical tunnels, like large wells, which are connected by a gently sloping underground channel bringing water by gravity. Through the centuries, the qanats have been not only a sustainable system for exploitation of groundwater resources but also an important factor for the socio-economic and cultural development of local communities. In this paper the Authors illustrate the main aspects of qanats under historical, cultural and socio-economic perspective and the recent decline of the qanat system. An original and still updating database of these type of hydraulic operas, implemented through the collection and analysis of documentary sources, cartographic data, and on-site measurements is then presented. The database, including qanats detected on regional to local scales, might be regarded as a valuable support for the recovery of these structures and a more efficient governance of water resources
Familial Amyloid Polyneuropathy Misdiagnosed as Systemic Sclerosis
Get PDFWe present the case of a 53-year-old woman of Portuguese ancestry with a diagnosis of progressive systemic sclerosis (SSc), proposed for haematopoietic stem cell transplantation (HSCT). Clinical re-evaluation when assessing eligibility for the procedure led to the alternative diagnosis of familial amyloid polyneuropathy (FAP). We discuss the clinical presentations of FAP and SSc, focusing on their overlapping and distinguishing features. We emphasize the need for a high level of suspicion in order to establish an early diagnosis of FAP in the absence of a family history, and provide prognostic and genetic counselling
Solution to the ghost problem in higher-derivative gravity
No full textWith standard Einstein gravity not being renormalizable at the quantum level there is much interest in studying higher-derivative quantum gravvity theories. Thus just as a Ricci-scalar–based action produces a propagator that behaves as a non-renormalizable 1/k2 at large k2, an action based on the square of the Ricci scalar behaves as a renormalizable 1/k4 at large k2. An action based on both the Ricci scalar and its square leads to a renormalizable propagator of the
generic Pauli-Villars form. However, given the form of the Hamiltonian and the propagator such theories are thought to be plagued by either energies that are unbounded from below or states of negative Dirac norm (the overlap of a ket with
its Hermitian conjugate bra). But when one constructs the quantum Hilbert space one finds (Bender and Mannheim) that in fact neither of these problems is actually present. The Hamiltonian turns out to not be Hermitian but to instead have an antilinear P T symmetry, and for this symmetry the needed inner product is the overlap of a ket with its P T conjugate bra. And this inner product is positive definite. Moreover, for the pure 1/k4 propagator the Hamiltonian turns out not to be diagonalizable, and again there are no states of negative energy or of negative norm. Instead there are states of zero norm, non-standard but perfectly acceptable
states that serve to maintain probability conservation. With the locally conformal invariant fourth-order derivative conformal gravity theory being in this category, it can be offered as a candidate theory of quantum gravity that is renormalizable and unitary in four spacetime dimensions
A Case of Graves’ Disease Following Vaccination with the Oxford-AstraZeneca SARS-CoV-2 Vaccine: Case Report and Review of the Literature
Get PDFA 57-year-old man presented to the outpatient clinic with tremor, palpitations, weight loss and fatigue 1 week after receiving the first dose of the Oxford-AstraZeneca SARS-CoV-2 vaccine (ChAdOx1 nCoV-19). Laboratory studies showed a suppressed TSH with elevated total and free T4. Thyroid peroxidase and thyroglobulin antibodies were elevated but thyrotropin receptor autoantibodies were indeterminate. Thyroid scintigraphy with technetium Tc-99m pertechnetate revealed increased diffuse, symmetric uptake. The patient was treated with thiamazole 15 mg three times a day and propranolol with resolution of his symptoms and normalization of his thyroid function tests until discontinuation of the antithyroid drug 6 months after symptom onset
Fuchs Syndrome with Isolated Oral Mucosa Lesions due to Severe Herpes Simplex Cheilitis in a Patient with Idiopathic Thrombocytopenic Purpura
Get PDFStevens-Johnson syndrome (SJS) is a severe dermatological disease classically characterized by erythematous target lesions and mucosal involvement. Fuchs syndrome is an incomplete presentation of SJS which has oral, conjunctival and genital manifestations but no skin lesions. To the best of our knowledge, our case of Fuchs syndrome in an 80-year-old man is the first such case related to herpes simplex virus (HSV)-1 infection to be described. Our patient quickly recovered following IVIG therapy, although specific treatment is still a topic of discussion. Research is required on this poorly understood dermatological disease to determine optimum therapy
4π-periodic AC Josephson current through a reconstructed quantum spin Hall constriction
No full textWe consider a Josephson junction based on a long constriction between the helical edges of a two-dimensional topological insulator, tunnel-coupled to two superconductors, pierced by a magnetic flux, and subjected to an external bias. We analyse the general case of a reconstructed constriction; namely, the two direction-conserving tunnel couplings may have different intensities. We show that our model, as in the absence of edge reconstruction, admits the occurrence of a 4π-periodic component in the AC Josephson current as a function of the magnetic flux. Such feature is robust in a wide range of parameters. A detailed discussion on the temperature dependence is also provided