First principles investigation of tunnel FETs based on nanoribbons from topological two-dimensional materials.

We explore nanoribbons from topological two-dimensional stanene as a channel material in tunnel field effect transistors. This novel technological option offers the possibility of building pure one-dimensional (1D) channel devices (comprised of a 1D chain of atoms) due to localized states placed at the nanoribbon edges. The investigation is based on first-principles calculations and multi-scale transport simulations to assess the performance of devices against industry requirements and their robustness with respect to technological issues like line edge roughness, detrimental for nanoribbons. We will show that edge states are robust with respect to the presence of non-idealities (e.g., atom vacancies at the edges), and that 1D-channel TFETs exhibit interesting potential for digital applications and room for optimization in order to improve the ION/IOFF at the levels required by the ITRS, while opening a path for the exploration of new device concepts at the ultimate scaling limits.

Gate-Tunable Atomically Thin Lateral MoS2 Schottky Junction Patterned by Electron Beam.

Among atomically thin two-dimensional (2D) materials, molybdenum disulfide (MoS2) is attracting considerable attention because of its direct bandgap in the 2H-semiconducting phase. On the other hand, a 1T-metallic phase has been revealed, bringing complementary application. Recently, thanks to top-down fabrication using electron beam (EB) irradiation techniques, in-plane 1T-metal/2H-semiconductor lateral (Schottky) MoS2 junctions were demonstrated, opening a path toward the co-integration of active and passive two-dimensional devices. Here, we report the first transport measurements evidencing the formation of a MoS2 Schottky barrier (SB) junction with barrier height of 0.13-0.18 eV created at the interface between EB-irradiated (1T)/nonirradiated (2H) regions. Our experimental findings, supported by state-of-the-art simulation, reveal unique device fingerprint of SB-based field-effect transistors made from atom-thin 1T layers.

Soft tissue regeneration using leukocyte-platelet rich fibrin after exeresis of hyperplastic gingival lesions: two case reports.

INTRODUCTION: Leukocyte-platelet rich fibrin belongs to a second generation of platelet concentrates that does not need biochemical blood manipulation. It is used for tissue healing and regeneration in periodontal and oral-maxillofacial surgery. We report two cases of hyperplastic gingival lesions treated by exeresis and application of leukocyte-platelet rich fibrin membranes in order to improve and accelerate tissue healing. CASE PRESENTATION: Two patients (a 78-year-old Caucasian woman and a 30-year-old Caucasian man) were treated for hyperplastic gingival lesions. They underwent to exeresis of lesions and application of leukocyte-platelet rich fibrin membranes. Tissue healing was clinically evaluated after 1, 3, 7, 14 and 30 postoperative days. No recurrences were observed after 2 years of semi-annual follow up. CONCLUSIONS: We obtained rapid and good healing of soft tissues probably due to the elevated content of leukocytes, platelets and growth factors in the leukocyte-platelet rich fibrin. Based on our results we suggest the use of leukocyte-platelet rich fibrin to cover wounds after exeresis of oral neoformations such as hyperplastic gingival lesions.

CT-Cisternography in Post-Surgical CSF Rhinorrhea. A Report of Two Cases.

Cerebrospinal fluid (CSF) rhinorrhea is a dangerous problem. CSF rhinorrhea implies an abnormal communication between the subarachnoid space and the nasal cavity, with subsequent leakage of CSF through the anterior nasal apertures. requiring surgical repair. Imaging techniques have evolved from conventional cranial radiography to polytomography, thin-section computed tomography (CT) and intrathecal water-soluble iodinated contrast agent-enhanced CT cisternography. We present two cases of post-surgical CSF rhinorrhea in which the best diagnostic findings were obtained by CT cisternography.

[Multiple simultaneous stratigraphy. Results with a 5-plane system for pediatric use]. / Stratigrafia multipla simultanea. Risultati di un sistema a 5 strati per uso pediatrico.

The authors report the results of a five-layer simultaneous multisection tomographic technique to be used in pediatric radiology, based on an appropriately selected series of Trimax rare-earth intensifying screens arranged in progressive speed order. The technique has been so far employed with excellent results in 100 children, especially during IVP, when X-ray examination is very frequently disturbed by ileocolic gas. The many advantages of the technique are emphasized: a) all sections are perfectly parallel and simultaneous, in the same respiratory phase and body position; b) film density is practically identical in all sections; c) there is considerable saving in time, machine consumption, and radiation dose.

Familial congenital bowing with short thick bones and metaphyseal changes, a distinct entity. Report of the clinical and radiological findings in two siblings.

The authors describe two siblings, a male and a female, with disproportionate short stature, rhizomelic-mesomelic shortening of the limb bones, marked bowing of the femora, moderate bowing of the humeri, radii and ulnae, straight tibiae and fibulae, normal hands, flared cupped metaphyses of the tibiae, ulnae, radii and ribs, and narrow chest. There was some improvement of the bone changes with advancing age. These two patients are similar to five other cases from the literature and strongly support Hall and Spranger's view that this pseudocampomelic condition most likely represents a distinct familial bowing syndrome. The differential diagnosis and the hereditary aspects in the two patients, are also briefly discussed.

Radiological findings in the hand in Seckel syndrome (bird-headed dwarfism).

Two patients with severe intrauterine growth retardation and bird-headed appearance are described. These two children had most of the clinical features of the so-called Seckel dwarfism. The radiological findings included: (1) ivory epiphyses affecting all phalanges in one patient and many phalanges in another; (2) cone-shaped epiphyses in the proximal phalanges; (3) marked disharmonic bone maturation between carpals and phalanges, between individual carpals, and from side to side; (4) alteration in the length of the hand bones, with considerable similarity of the metacarpophalangeal pattern between the two children; (5) relatively small carpals, which have an angular configuration; and (6) relatively normal or increased cortical thickness of the metacarpals.

Double right tracheal bronchus. A case report in an infant.

An apparently unique case of double right tracheal bronchus supplying the whole right upper lobe is described in a 12-month-old infant presenting with a right paratracheal opacity, persisting cough, and ventricular septal defect. The two tracheal bronchi, initially discovered on tomography, were confirmed by tracheobronchography, which demonstrated also the absence of other upper lobe branches. At surgery, the upper lobe was atelectatic, and its blood supply was abnormal.

Idiopathic esophagopleural fistula in the newborn. A review, with a case report.

Idiopathic rupture of the esophagus in the neonate is a rare event, probably related to the same mechanism of ischemic necrosis responsible for other "spontaneous" g.i. tract perforations in the newborn. The laceration is usually located on the right aspect of the distal esophagus and is complicated by esophagopleural fistula and hydropneumothorax. Plain chest film and esophagography are diagnostic. The condition is an emergency one and usually carries a bad prognosis without prompt surgical repair. A typical case is reported in a baby who survived without early surgery; a residual tiny blind pouch and a small hiatal hernia required surgery at 1 year of age.

Intrauterine growth retardation. A report of two cases with bird-headed appearance, skeletal changes and peripheral GH resistance.

Two cases of severe intrauterine growth retardation, a boy and a girl studied for 7 and 10 years respectively, are reported. Both patients showed peculiar cranio-facial abnormalities as observed in the so-called Seckel's syndrome, an appearance of premature aging, peripheral GH resistance which was probably due to deficiency in Somatomedin A production, sella areas and volumes consistently at the upper limits of normal when related to the patients' height, and dysharmonic skeletal maturation ivory cone-shaped epiphyses of the tubular bones of the hands.

CT for assessing feasibility of separation of thoracopagus twins.

The value of the angio-computed tomography technique for evaluating communication between cardiac cavities of the two hearts in conjoined twins is reported. After injecting contrast medium into the peripheral vein of one of the twins, the increase in density values of the heart in the other twin suggested shunting between the two hearts.