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1.
Nanoscale ; 9(48): 19390-19397, 2017 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-29206255

RESUMO

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.

2.
Nano Lett ; 16(6): 3788-94, 2016 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-27152475

RESUMO

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.

3.
J Med Case Rep ; 9: 252, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26527036

RESUMO

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.


Assuntos
Fibrina/uso terapêutico , Granuloma de Células Gigantes/tratamento farmacológico , Granuloma de Células Gigantes/patologia , Granuloma de Células Gigantes/cirurgia , Regeneração/efeitos dos fármacos , Adulto , Idoso , Plaquetas/metabolismo , Feminino , Humanos , Leucócitos/metabolismo , Masculino , Radiografia Panorâmica
4.
Neuroradiol J ; 20(6): 642-5, 2007 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-24299998

RESUMO

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.

5.
Phys Rev B Condens Matter ; 53(4): 2020-2025, 1996 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9983664
6.
Phys Rev B Condens Matter ; 52(24): 17406-17412, 1995 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9981170
7.
9.
Phys Rev B Condens Matter ; 49(23): 16548-16560, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10010809
10.
Radiol Med ; 76(4): 333-6, 1988 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-3187090

RESUMO

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.


Assuntos
Tomografia por Raios X/métodos , Criança , Humanos , Tomografia por Raios X/instrumentação , Urografia/instrumentação , Urografia/métodos , Filme para Raios X , Ecrans Intensificadores para Raios X
12.
Pediatr Radiol ; 14(5): 323-7, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6472918

RESUMO

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.


Assuntos
Doenças do Desenvolvimento Ósseo/diagnóstico por imagem , Estatura , Doenças do Desenvolvimento Ósseo/genética , Doenças do Desenvolvimento Ósseo/patologia , Osso e Ossos/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Radiografia
13.
Pediatr Radiol ; 13(3): 156-8, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6866574

RESUMO

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.


Assuntos
Brônquios/anormalidades , Traqueia/anormalidades , Broncografia , Humanos , Lactente , Masculino , Atelectasia Pulmonar/etiologia , Tomografia por Raios X , Traqueia/diagnóstico por imagem
15.
Pediatr Radiol ; 13(1): 19-24, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6682547

RESUMO

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.


Assuntos
Osso e Ossos/patologia , Nanismo/diagnóstico por imagem , Retardo do Crescimento Fetal/diagnóstico por imagem , Mãos/diagnóstico por imagem , Cabeça/anormalidades , Determinação da Idade pelo Esqueleto , Desenvolvimento Ósseo , Ossos do Carpo/diagnóstico por imagem , Ossos do Carpo/patologia , Criança , Diagnóstico Diferencial , Epífises/diagnóstico por imagem , Epífises/patologia , Feminino , Humanos , Masculino , Metacarpo/diagnóstico por imagem , Metacarpo/patologia , Gravidez , Progéria/diagnóstico , Síndrome
16.
Rofo ; 137(1): 88-91, 1982 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6213535

RESUMO

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.


Assuntos
Fístula Esofágica/diagnóstico por imagem , Fístula/diagnóstico por imagem , Doenças do Recém-Nascido/diagnóstico por imagem , Doenças Pleurais/diagnóstico por imagem , Asfixia Neonatal/complicações , Doenças do Esôfago/diagnóstico por imagem , Esôfago/irrigação sanguínea , Humanos , Recém-Nascido , Isquemia/complicações , Masculino , Necrose , Radiografia , Ruptura Espontânea
19.
Eur J Pediatr ; 137(2): 237-42, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7198044

RESUMO

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.


Assuntos
Retardo do Crescimento Fetal/diagnóstico , Desenvolvimento Ósseo , Criança , Disostose Craniofacial/diagnóstico , Resistência a Medicamentos , Feminino , Hormônio do Crescimento , Mãos/diagnóstico por imagem , Humanos , Masculino , Gravidez , Radiografia , Somatomedinas/deficiência
20.
J Comput Assist Tomogr ; 5(4): 574-6, 1981 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7264000

RESUMO

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.


Assuntos
Coração Fetal/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Gêmeos Unidos/diagnóstico por imagem , Sulfato de Bário , Cateterismo Cardíaco , Sistema Digestório/diagnóstico por imagem , Feminino , Humanos , Recém-Nascido , Gravidez , Radiografia Abdominal , Gêmeos Unidos/cirurgia
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