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a b s t r a c tIn the present study six exceptional large size metallic nails, a dagger and a sickle from the Late Bronze Age archaeological site of Figueiredo das Donas (Central Portugal) have been analysed by EDXRF, micro-EDXRF and X-ray digital radiography for the study of material composition and technology of fabrication. The combination of these analytical and examination techniques showed that all artefacts are made of bronze with As, Sb and Pb impurities, and that the nails were most likely manufactured using the casting-on technique. These results reinforce the use of binary bronze by Late Bronze Age in the region, and the incorporation of new fabrication technologies that resulted from ancient spheres of interaction.

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Near equiatomic Ni-Ti films have been deposited by magnetron co-sputtering on TiN films with a topmost layer formed by <111> oriented grains (TiN/SiO 2 /Si(100) substrate) in a chamber installed at a synchrotron radiation beamline. In-situ X-ray diffraction during Ni-Ti film growth and their complementary ex-situ characterization by Auger electron spectroscopy, scanning electron microscopy and electrical resistivity measurements during temperature cycling have allowed us to establish a relationship between the structure and processing parameters. 2A preferential development of <110> oriented grains of the B2 phase since the beginning of the deposition has been observed (without and with the application of a substrate bias voltage of -45 and -90V). The biaxial stress state is considerably influenced by the energy of the bombarding ions, which is dependent on the substrate bias voltage value applied during the growth of the Ni-Ti film. Furthermore, the present work reveals that the control of the energy of the bombarding ions is a promising tool to vary the transformation characteristics of Ni-Ti films, as shown by electrical resistivity measurements during temperature cycling.The in-situ study of the structural evolution of the growing Ni-Ti film as a consequence of changing the Ti:Ni ratio during deposition (on a TiN<111> layer) has also been performed. The preferential growth of <110> oriented grains of the Ni-Ti B2 phase has been as well observed despite the precipitation of Ti 2 Ni during the deposition of a Ti-rich Ni-Ti film fraction. Functionally graded Ni-Ti films should lead to an intrinsic "two-way" shape memory effect which is a plus for the miniaturization of NiTi films based devices in the field of micro-electro-mechanical systems.3

Abstract. NiTi endodontic files allow for clinical enlargement of harshly curved root canals. However, files rotated under severe flexion might fracture unexpectedly, remain inside teeth and thus, hinder treatment outcome. ProFile .06(35) are among the most commonly used rotary files. In the present study, 10 of these brand new instruments were used to perform DSC on their cutting regions and determine the amount of R-phase present at 10, 20, 37, and 65ºC, both during cooling and heating programmed cycles. Another 48 new ProFile .06(35) instruments underwent rotation/flexion assays at 300 rpm and 10 mm radius of curvature. Files were divided into four groups of 12 instruments each. Each group was tested at 10, 20, 37, and 65ºC. The number of cycles to fracture (N f ) and the length of the broken segment (L f ) were determined for each tested file. Results show no statistically s as for L f in all groups. On the contrary, N f depends highly on testing temperature: as temperature increases from 10 to 37 ºC, N f strikingly decreases; from 37 and 65 ºC, no significant changes in N f occur. As for DSC results, it is clearly shown that R-phase is most abundant at 10 ºC and consistently decreases up to 37ºC, both during heating and cooling; from 37 to 65 ºC, the quantity of R-phase in the alloy is negligible. In conclusion, it is shown that fatigue resistance in ProFile .06(35) instruments is not only highly enhanced but also proportional to the amount of R-phase in the alloy. BackgroundRoot canal degree of curvature is highly dependent on tooth type [1-3] as canal shape roughly corresponds to its root shape [4]. Endodontic literature agrees on most root canals having some degree of curvature [5]. Stainless steel files produce more canal transportation in curved canals than their Ni-Ti rotary counterparts, both in acrylic simulated root canals [6,7], and in extracted teeth [8,9]. Dalton et al. [10] showed, in vivo, that Ni-Ti files and stainless steel files are equally effective in reducing intracanalar bacteria when matched for size. However, if more tapered Ni-Ti files are used, then rotary files allow for better irrigation at working length [11,12] and, hence, for a better apical cleaning. The faster results obtained with Ni-Ti rotary files [13,14] have also made them increasingly popular among clinicians and their use is now even taught at undergraduate level [15][16][17].The major drawback of Ni-Ti instrumentation is file rupture. Iqbal et al. [18] report that the odds for rotary Ni-Ti file breaking were seven times more than for hand stainless steel file separation in graduate clinical setting. Spili et al. [19] report similar findings in a population of experienced endodontists, which accounts for the overall perception among general practitioners that Ni-Ti files break more often than hand stainless steel files [20]. Reliable data on Ni-Ti fragments that remain inside root canals is still scarce. Spili et al. [19] are, so far, the only authors who investigated the influence of retained Ni-Ti fragments on p...