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The adoption of graphene in electronics, optoelectronics and photonics is hindered by the difficulty in obtaining high quality material on technologically-relevant substrates, over wafer-scale sizes and with metal contamination levels compatible with industrial requirements. To date, the direct growth of graphene on insulating substrates has proved to be challenging, usually requiring metal-catalysts or yielding defective graphene. In this work, we demonstrate a metal-free approach implemented in commercially available reactors to obtain high-quality monolayer graphene on c-plane sapphire substrates via chemical vapour deposition (CVD). We identify via low energy electron diffraction (LEED), low energy electron microscopy (LEEM) and scanning tunneling microscopy (STM) measurements the Al-rich reconstruction root31R9 of sapphire to be crucial for obtaining epitaxial graphene. Raman spectroscopy and electrical transport measurements reveal high-quality graphene with mobilities consistently above 2000 cm2/Vs. We scale up the process to 4-inch and 6-inch wafer sizes and demonstrate that metal contamination levels are within the limits for back-end-of-line (BEOL) integration. The growth process introduced here establishes a method for the synthesis of wafer-scale graphene films on a technologically viable basis., Comment: 15 main text pages, 4 main text figures, 13 supplementary information pages, 12 supplementary figures, 3 supplementary tables

Guidelines are an essential tool to ensure an optimal clinical governance in oncology. The Province of Trento started a research project whose aim is to develop a system for supporting and controlling the best evidence-based oncological care process based on guidelines. The significant role of ontologies for the semantic interoperability of such a system is pointed out.

Telemetric, intraoperative frozen section diagnosis may be a useful tool for rural hospitals lacking an in-house pathology service. As a part of a Health Ministry Project on Telemedicine in Trentino (northern Italy), we developed a static telemicroscopy system (STeMiSy). This system connects the rural hospital of Cles with the main hospital of Trento. The two hospitals are 40 kilometers apart, and the road connecting the two towns runs across the mountains and has a heavy traffic. Before putting STeMiSy into practice, we tested the software and hardware on the LAN of the regional hospital system, by connecting the pathology services of Trento and Rovereto (20 kilometers apart). This test phase lasted three months and has not revealed major problems in the LAN nor in the robotic microscope, which was always precise and reliable. The quality of the images and the speed of transmission were largely sufficient for intraoperative frozen section diagnosis. Minor details of the histological slides were not always appreciated on the panoramic view. This loss of some details may be due to the quality of the panoramic view, which represents the 'surfing map' to read the cases. Nevertheless, the recognition of these small details was not so relevant as to change the surgical approaches. An audioconference system, utilizing the same transmission channel, not only slightly slowed the transmission but also caused some instability to the system. The audioconference system has therefore been abandoned, and when necessary we used the normal telephone. Macroscopic images of the whole surgical specimen, the surgeon's responsibility for the sampling, good technical quality of the slide, and good training will allow us to perform remote frozen section diagnosis in the absence of the pathologist. We believe that the main, and probably only, difficulty for this approach is not of a technical nature, but reflects the pathologist's resistance to making a remote video diagnosis.

1. Cardiac effects on norbormide and verapamil were compared in single ventricular myocytes, right atria, and Langendorff perfused hearts isolated from guinea-pigs. 2. In ventricular myocytes, norbormide 50 microM inhibited the peak calcium current (ICa) by 49.6 +/- 3.9% without altering the shape of the current-voltage relationship; verapamil 1 microM inhibited ICa by 83.2 +/- 3.3%. Neither norbormide nor verapamil affected ICa at the first beat after a 3 min quiescence period; during repeated depolarizations, both drugs cumulatively blocked ICa (use-dependence), with time constants of 23.0 +/- 7.0 s for norbormide and 91.3 +/- 8.4 s for verapamil. 3. In constant-flow perfused hearts electrically driven at 2.5 Hz or 3.3 Hz, both norbormide and verapamil concentration-dependently decreased ventricular contractility (dP/dtmax), atrio-ventricular (AV) conduction velocity and coronary pressure. Intraventricular conduction velocity was slightly decreased by norbormide but not by verapamil. At an equivalent change in AV conduction, norbormide depressed heart contractility less than verapamil. The effects of norbormide on AV conduction, intraventricular conduction, and contractility were frequency-dependent. Furthermore, the curves correlating the mechanical and electrical effects of norbormide at the two frequencies used were apparently coincident, while those of verapamil were clearly separated. 4. In spontaneously beating right atria, norbormide and verapamil decreased the frequency of sinus node (SA) in a concentration-dependent way. At an equivalent effect on the AV conduction, norbormide exerted a greater effect on sinus frequency than verapamil. 5. These results indicate that in guinea-pig heart norbormide has the pharmacological profile of a Ca-antagonist with strong electrophysiological properties. In comparison with verapamil, norbormide is more selective on SA and AV node tissues and exerts a weaker negative inotropic effect on ventricles. In principle, this pattern of effects may be an advantage in treating supraventricular tachyarrhythmias in patients with heart failure. The effect of norbormide on intraventricular conduction may represent an additional antiarrhythmic mechanism.

To develop a computerized analysis method that could reflect not only cellular anaplasia but also the orientation (PV) of neoplastic elements and could allow the separation of low (grade G 1 and G 2a) and high (G 2b) grades of superficial papillary bladder tumors (SPBTs).Cellular anaplasia is based on classic morphometric parameters, such as mean and standard deviation of area, perimeter, roundness and aspect ratio (length/width ratio) of 50 papillary bladder tumors (16 G 1, 10 G 2a and 24 G 2b according to Pauwels). Orientation of the major axis of each nucleus with respect to the true basal membrane was calculated using the SD of valve distribution.No statistically significant differences were found between cases showing contiguous grades (G 1 versus G 2a or G 2a versus G 2b). PV, SD of the area and SD of the perimeter were the parameters that could significantly distinguish between G 1 and G 2b and between G 1 plus G 2a and G 2b (P.05). When comparing G 1 with G 2a plus G 2b, only PV and SD of the area were statistically significant.Quantification of the irregularities in the orientation of nuclei with respect to the basal membrane may improve morphometric classification of low grade SPBTs.

Telepathology is a field of telemedicine that enables the exchange of histologic and cytologic images for consultations among pathologists of two or more remote institutions, through a suitable communication channel. The Internet can connect several scientific and medical institutions because of the existence of a set of standard protocols that allow different computers to communicate; multimedia electronic mail is one such protocol, which allows asynchronous transmission of multimedia documents, i.e., including text, images, movies, and sounds. The aim of the present article is to test a novel approach in which Internet multimedia electronic mail is used as a communication medium to obtain an asynchronous telepathology tool for remote consultation. To assess the diagnostic validity of the method, 48 cases of fine-needle aspiration cytology of breast lesions were sent from Udine to Trento, Italy. Comparisons between local and remote diagnoses, and cytologic diagnoses versus subsequent histologic reports demonstrated that Internet multimedia electronic mail is suitable for remote consultation. Internet multimedia electronic mail thus presents an additional diagnostic tool that is easy to use, available on a wide range of computers, and inexpensive, because its cost is independent of distance.

One of the major issues in graphene-based optoelectronics is to scale-up high-performing devices. In this work, we report an original approach for the fabrication of efficient optoelectronic devices from scalable tungsten disulfide (WS2)/graphene heterostructures. Our approach allows for the patterned growth of WS2 on graphene and facilitates the realization of ohmic contacts. Photodetectors fabricated with WS2 on epitaxial graphene on silicon carbide (SiC) present, when illuminated with red light, a maximum responsivity R ~220 A W-1, a detectivity D* ~2.0 × 109 Jones and a -3 dB bandwidth of 250 Hz. The retrieved detectivity is 3 orders of magnitude higher than that obtained with graphene-only devices at the same wavelength. For shorter illumination wavelengths we observe a persistent photocurrent with a nearly complete charge retention, which originates from deep trap levels in the SiC substrate. This work ultimately demonstrates that WS2/graphene optoelectronic devices with promising performances can be obtained in a scalable manner. Furthermore, by combining wavelength-selective memory, enhanced responsivity and fast detection, this system is of interest for the implementation of 2d-based data storage devices.

Kinematic recordings in a reach and drop task were compared between 12 preschool children with autism without mental retardation and 12 gender and age-matched normally developing children. Our aim was to investigate whether motor anomalies in autism may depend more on a planning ability dysfunction or on a motor control deficit. Planning and control processes were separately investigated by examining kinematic recordings divided into primary movement- (planning-based) and corrective submovement- (control-based) phases. Despite longer movement durations, participants with autism were as accurate in their movements as normally developing children were and showed a preserved movement structure. No differences were observed for the initial movement phases for hand velocity, accuracy and inter-trial variability. Our main finding was that of a group difference in proximity of the target, at transition from planning-based to control-based movement guidance. At primary movement conclusion, the normally developing children had already reduced velocity and begun orienting their hands for ball drop. Also, they tended to terminate movements within the same movement unit that had transported the hand into the target box. Compared to this group, participants with autism reached this stage with less preparation: their speed was significantly higher, wrist inclination reduced and they showed further movement units after entering the box over the vast majority of trials. These additional movement units were presumed to represent late control-based spatial adjustments. Hence, our data support the hypothesis that children with autism have a greater need for corrective submovements. We provide evidence that motor anomalies in autism might be determined either by a disruption in planning-control integration, or by a limited planning process capacity, as participants with autism might have been able to plan only the very beginning of the movement, leaving its final phases to further planning on the fly, with important consequences on movement time optimization. © 2010 Elsevier Ltd. All rights reserved.

Black phosphorus (bP) has emerged as an interesting addition to the category of two-dimensional materials. Surface-science studies on this material are of great interest, but they are hampered by bP's high reactivity to oxygen and water, a major challenge to scanning tunneling microscopy (STM) experiments. As a consequence, the large majority of these studies were performed by cleaving a bulk crystal in situ. Here we present a study of surface modifications on exfoliated bP flakes upon consecutive annealing steps, up to 550 °C, well above the sublimation temperature of bP. In particular, our attention is focused on the temperature range 375 °C-400 °C, when sublimation starts, and a controlled desorption from the surface occurs alongside with the formation of characteristic well-aligned craters. There is an open debate in the literature about the crystallographic orientation of these craters, whether they align along the zigzag or the armchair direction. Thanks to the atomic resolution provided by STM, we are able to identify the orientation of the craters with respect to the bP crystal: the long axis of the craters is aligned along the zigzag direction of bP. This allows us to solve the controversy, and, moreover, to provide insight in the underlying desorption mechanism leading to crater formation.

Cutaneous myiasis is a common travel-associated dermatosis caused by fly larvae. We report an unusual case of furuncular myiasis caused by Dermatobia hominis that was associated with signs of systemic inflammation. In this case study, morphological and novel molecular approaches were used to identify and characterize the larvae responsible for human infestation.

We investigated eye-hand coordination in children with autism spectrum disorders (ASD) in comparison with age-matched normally developing peers. The eye-hand correlation was measured by putting fixation latencies in relation with pointing and key pressing responses in visual detection tasks where a gap-overlap paradigm was used and compared to fixation latencies in absence of manual response. ASD patients showed less efficient eye-hand coordination, which was particularly evident when pointing towards a target was being fixated. The data of normally developing participants confirmed that manual gap effects are more likely for more complex hand movements. An important discrepancy was discovered in participants with ASD: beside normal eye gap effects, they showed no concurrent hand gap effects when pointing to targets. This result has been interpreted as a further sign of inefficient eye-hand coordination in this patient population. © 2012 Springer Science+Business Media, LLC.

On the SiC(0001) surface (the silicon face of SiC), epitaxial graphene is obtained by sublimation of Si from the substrate. The graphene film is separated from the bulk by a carbon-rich interface layer (hereafter called the buffer layer) which in part covalently binds to the substrate. Its structural and electronic properties are currently under debate. In the present work we report scanning tunneling microscopy (STM) studies of the buffer layer and of quasi-free-standing monolayer graphene (QFMLG) that is obtained by decoupling the buffer layer from the SiC(0001) substrate by means of hydrogen intercalation. Atomic resolution STM images of the buffer layer reveal that, within the periodic structural corrugation of this interfacial layer, the arrangement of atoms is topologically identical to that of graphene. After hydrogen intercalation, we show that the resulting QFMLG is relieved from the periodic corrugation and presents no detectable defect sites. (C) 2012 Elsevier Ltd. All rights reserved.

Movement disturbances play an intrinsic part in autism. Upper limb movements like reach-and-throw seem to be helpful in early identification of children affected by autism. Nevertheless few works investigate the application of classifying methods to upper limb movements. In this study we used a machine learning approach Support Vector Machine (SVM) for identifying peculiar features in reach-and-throw movements. 10 pre-scholar age children with autism and 10 control subjects performing the same exercises were analyzed. The SVM algorithm proved to be able to separate the two groups: accuracy of 100% was achieved with a soft margin algorithm, and accuracy of 92.5% with a more conservative one. These results were obtained with a radial basis function kernel, suggesting that a non-linear analysis is possibly required. ©2009 IEEE.