Experimental Investigation on Two Displacement Catamarans: Systematic Variation of Displacement, Clearance & Stagger

The aim of this study has been the evaluation of the effects due to the variation of longitudinal stagger, transverse separation and displacement on the resistance of two symmetric hull forms suitable for catamaran configuration over a speed range corresponding to Fn < 0.5. To achieve this aim at the Dipartimento di Ingegneria Navale di Napoli (DIN) an intensive experimental investigation has been carried out on two models in three configurations: monohull, symmetric and staggered catamaran. In particular, for one model, 6 clearances in the symmetrical configuration and 4 longitudinal staggers have been tested; for the other one 3 clearances and 3 staggers have been tested. The influence of displacement on resistance has been evaluated by testing the models for three different displacements

Stiffened panels damage tolerance determination using an optimization procedure based on a linear delamination growth approach

The damage tolerance of delaminated composite panels under compressive load is usually numerically evaluated by means of computationally expensive non-linear approaches. In this study, an alternative numerical linear approach, able to mimic the delamination propagation initiation, is proposed. With the aim to exploit its benefits, in terms of computational costs reduction, the proposed linear methodology has been used in this study in conjunction with an optimization analysis to assess the damage tolerance of stiffened composite panels with an impact induced delamination under compression. Indeed, the optimization was aimed to find the minimum delamination growth initiation load for a delaminated stiffened panel with variable delamination size and position, providing indications on the damage tolerance capability of the stiffened panel with an arbitrary positioned and sized delamination induced (as an example) by a low energy impact

Hallux rigidus: current concepts review and treatment algorithm with special focus on interposition arthroplasty

Hallux rigidus represents a surgical challenge, with a multitude of possible surgical options, but with no ideal procedures.&nbsp; The propose of this paper was to review the actual knowledge on the operative techniques, paying particular attention to the evolution of interposition arthroplasties, as an alternative to arthrodesis and prosthesis in the advanced stages of the disease

Coordination of spatial and temporal laser beam profile towards ultra-fine feature fabrication in laser powder bed fusion

Laser powder bed fusion (LPBF) is a metal additive manufacturing technology that provides high shape and application flexibilities. Although dimensional flexibility is high in theory thanks to the non-contactless micro range processing tool (i.e., laser beam) and powder, the fabrication robustness of thin and ultra-thin features (dnominal?200 ?m) is still a challenge for the technology. In particular, geometrical fidelity and dimensional accuracy problems have been raising towards the ultra-thin fabrication segment. Although there were different studies that presented solutions for robust and sustainable fabrication strategy in ultra-thin segment in the literature, the vast majority of them focused on process itself directly, and the technological feasibility of the LPBF systems was not considered. However, without considering technological feasibility of the LPBF systems, the presented solutions in the literature are far from providing solid basis and they may mislead the users in the case of direct application. In this sense, this study mainly focused on the scanning capability of the systems for features under 200 µm dimensional range with temporal and spatial laser beam management in the case of conventional scanning strategy (contour and hatch). For this purpose, the fabrication process reduced to the two dimensions (scanning region) via the laser marking tests, and custom laser parameters, which are provided by the industrial grade open architecture LPBF system, has been used. Here, it has been reported that two different errors related to scanning performance and process parameters for continuous and pulsed wave laser emission modes, separation, and compensation of these two errors, and investigation methodology for technological feasibility of the LPBF machines. Moreover, in the pulsed wave laser emission mode, two linear parameters have been presented to optimize spatial energy distribution. Considering the results coming from the practical observations and measurements, it is possible to indicate that the technological feasibility of the utilized LPBF system should be key concern before laser or scan related parameters optimization. The results show that if correct scanning parameters have been selected in the technological feasibility window of the system, scan trajectories based on conventional hatching method can be carried out with sufficient geometrical accuracy

LO SPAZIO DELLA PARAFRASI E DELLA RIFORMULAZIONE NELLE GRAMMATICHE SCOLASTICHE

Attraverso l’analisi di un corpus di quindici manuali  scolastici si offre una prima ricognizione sul ruolo della parafrasi nei libri di grammatica per la scuola secondaria di secondo grado. L’intervento è articolato in due parti: la prima mette a fuoco obiettivi, presupposti metodologici e definizioni documentate nel corpus; la seconda mira a far emergere e risaltare le motivazioni teoriche e pratiche delle scelte delle grammatiche relativamente a esercizi e tipi di testi proposti, incrociando i dati emersi con gli studi linguistici sulla parafrasi. A corredo dell’analisi, sono fatte alcune considerazioni su come possano essere coniugate teoria e finalità didattiche in funzione della piena comprensione dei testi e della riflessione storica e metalinguistica sulle varietà letterarie e specialistiche dell’italiano. Paraphrase and reformulation in school textbooksThrough the analysis of a corpus of fifteen school textbooks, this survey investigates the role of paraphrases in textbooks for secondary schools. The first part focuses on objectives, methodological assumptions and definitions documented in the corpus; the second part aims to identify and highlight the theoretical and practical reasons for the choice of textbooks in relation to exercises and types of texts proposed, crossing the data with language studies on paraphrase. In support of the analysis, some considerations are made on how theory and teaching objectives can be combined in order to fully understand the texts as well as historical and metalinguistic reflections on the literary and specialized varieties of Italian

Neonicotinoid Clothianidin reduces honey bee immune response and contributes to Varroa mite proliferation

The neonicotinoid Clothianidin has a negative impact on NF-\u3baB signaling and on immune responses controlled by this transcription factor, which can boost the proliferation of honey bee parasites and pathogens. This effect has been well documented for the replication of deformed wing virus (DWV) induced by Clothianidin in honey bees bearing an asymptomatic infection. Here, we conduct infestation experiments of treated bees to show that the immune-suppression exerted by Clothianidin is associated with an enhanced fertility of the parasitic mite Varroa destructor, as a possible consequence of a higher feeding efficiency. A conceptual model is proposed to describe the synergistic interactions among different stress agents acting on honey bees

Neonicotinoid Clothianidin reduces honey bee immune response and contributes to Varroa mite proliferation

The neonicotinoid Clothianidin has a negative impact on NF-κB signaling and on immune responses controlled by this transcription factor, which can boost the proliferation of honey bee parasites and pathogens. This effect has been well documented for the replication of deformed wing virus (DWV) induced by Clothianidin in honey bees bearing an asymptomatic infection. Here, we conduct infestation experiments of treated bees to show that the immune-suppression exerted by Clothianidin is associated with an enhanced fertility of the parasitic mite Varroa destructor, as a possible consequence of a higher feeding efficiency. A conceptual model is proposed to describe the synergistic interactions among different stress agents acting on honey bees

Manuale d'uso del logo INAF - Istituto Nazionale di Astrofisica

Nel presente Manuale d'uso sono dettagliate alcune indicazioni utili per l'utilizzo del logo dell'INAF, Istituto Nazionale di Astrofisica, e le modalità per la richiesta di concessione in utilizzo del logo stesso da parte di terzi. Dopo diciassette anni dal suo progetto, il logo ha di recente avuto un restyling curato da Stefano Asili, già ideatore del logo originario. Gli interventi di restyling, pur fatti con mano leggera, sono sostanziali: dalla scelta del carattere tipografico alle proporzioni, agli allineamenti. Segnaliamo infatti l’introduzione di un nuovo carattere tipografico: l’Eurostile di Aldo Novarese. Progettato nel 1962 - su base del precedente Microgramma del 1952, di Alessandro Butti e dello stesso Novarese - l’Eurostile è diventato lo standard dell’immaginario spaziale. Da Hal 9000 di Kubrick a un'innumerevole serie di film, questo carattere perennemente moderno è sembrato irrinunciabile per un ente scientifico che scandaglia ogni giorno gli oggetti più lontani dell’universo. Sono riportati anche alcuni elementi esemplificativi di immagine coordinata e alcune pratiche di utilizzo errato, utili a orientare senza errori i designer che avranno a che fare con la nuova identità. Il risultato è un marchio che non cambia di senso ma acquista in forza, come forte è la decisione di declinare il logo esteso solo in italiano

Varroa destructor is an effective vector of Israeli acute paralysis virus in the honeybee, Apis mellifera.

The Israeli acute paralysis virus (IAPV) is a significant marker of honeybee colony collapse disorder (CCD). In the present work, we provide the first evidence that Varroa destructor is IAPV replication-competent and capable of vectoring IAPV in honeybees. The honeybees became infected with IAPV after exposure to Varroa mites that carried the virus. The copy number of IAPV in bees was positively correlated with the density of Varroa mites and time period of exposure to Varroa mites. Further, we showed that the mite-virus association could possibly reduce host immunity and therefore promote elevated levels of virus replication. This study defines an active role of Varroa mites in IAPV transmission and sheds light on the epidemiology of IAPV infection in honeybees