10 research outputs found
The explicit Mordell conjecture for families of curves
In this article we prove the explicit Mordell Conjecture for large families of curves. In addition, we introduce a method, of easy application, to compute all rational points on curves of quite general shape and increasing genus. The method bases on some explicit and sharp estimates for the height of such rational points, and the bounds are small enough to successfully implement a computer search. As an evidence of the simplicity of its application, we present a variety of explicit examples and explain how to produce many others. In the appendix our method is compared in detail to the classical method of Manin-Demjanenko and the analysis of our explicit examples is carried to conclusion
Reconstructive head and neck surgery: oncological and functional results.
The aim of this retrospective study is to review the experience in performing head and neck reconstruction surgery between 1989 and 2009 at the ENT Department of the University Hospital of Ferrara, Italy, considering the oncological as well as the functional and psychological outcome.
Methods and study design. Thirty-three consecutive patients were enrolled. Patients underwent flap reconstruction following primary or salvage surgery for squamous cell carcinoma of the oral cavity or oropharynx. Oncological results in terms of survival rate and disease-free interval, as well as functional and psychological results were evaluated.
Results. The oncological results, i.e. survival rate related to cancer stage and disease-free interval, were in agreement with those of the literature. Functional assessment, swallowing function and speech intelligibility were statistically poorer in patients affected by oropharyngeal malignancies than in patients affected by oral cancer. Quality of life was compromised in terms of reduced relationships and onset of depression or irritability.
Conclusions. Reconstructive surgery can be considered a relatively standard procedure in the treatment of head and neck cancer. The main drawback is still related to the major impact on patients' quality of life and functional status
Tetra-phenyl porphyrin based thin film transistors
Long channel p-type field effect transistors were realized by using 5,10,15,20-tetra-phenyl porphyrin. The organic was deposited by spray coating from a chloroform solution onto thermally oxidized silicon substrates where chromium source and drain contacts were realized. Coplanar and structures with a high geometric ratio were defined by fine line lithography in order to increase the collected current. Gate bias up to -100 V and drain to source bias up to -30 V were used. Leakage paths through the dielectric, also at low voltage, were evidenced by monitoring the gate current. Source to drain currents were evaluated considering the Kirchhoff law keeping into account the leakage currents. On these basis, a complete characterization of the transistors was carried out. Threshold voltage equal to -7.5 V was estimated on a 40 Pro long device. Hole field effect mobility equal to 0.007 cm(2)/Vs was evaluated from zero-bias channel conductance. Besides, field dependent mobility as high as 0.012 cm(2)/Vs and transconductance equal to 6.5 muA/V were estimated from the analysis of the achieved results. The operation mechanism of the transistor and current modulation at low and high field is presented and discussed. (C) 2003 Elsevier Science B.V. All rights reserved
Autoimmunity affecting the biliary tract fuels the immunosurveillance of cholangiocarcinoma
: Cholangiocarcinoma (CCA) results from the malignant transformation of cholangiocytes. Primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) are chronic diseases in which cholangiocytes are primarily damaged. Although PSC is an inflammatory condition predisposing to CCA, CCA is almost never found in the autoimmune context of PBC. Here, we hypothesized that PBC might favor CCA immunosurveillance. In preclinical murine models of cholangitis challenged with syngeneic CCA, PBC (but not PSC) reduced the frequency of CCA development and delayed tumor growth kinetics. This PBC-related effect appeared specific to CCA as it was not observed against other cancers, including hepatocellular carcinoma. The protective effect of PBC was relying on type 1 and type 2 T cell responses and, to a lesser extent, on B cells. Single-cell TCR/RNA sequencing revealed the existence of TCR clonotypes shared between the liver and CCA tumor of a PBC host. Altogether, these results evidence a mechanistic overlapping between autoimmunity and cancer immunosurveillance in the biliary tract
Autoimmunity affecting the biliary tract fuels the immunosurveillance of cholangiocarcinoma
International audienceCholangiocarcinoma (CCA) results from the malignant transformation of cholangiocytes. Primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) are chronic diseases in which cholangiocytes are primarily damaged. Although PSC is an inflammatory condition predisposing to CCA, CCA is almost never found in the autoimmune context of PBC. Here, we hypothesized that PBC might favor CCA immunosurveillance. In preclinical murine models of cholangitis challenged with syngeneic CCA, PBC (but not PSC) reduced the frequency of CCA development and delayed tumor growth kinetics. This PBC-related effect appeared specific to CCA as it was not observed against other cancers, including hepatocellular carcinoma. The protective effect of PBC was relying on type 1 and type 2 T cell responses and, to a lesser extent, on B cells. Single-cell TCR/RNA sequencing revealed the existence of TCR clonotypes shared between the liver and CCA tumor of a PBC host. Altogether, these results evidence a mechanistic overlapping between autoimmunity and cancer immunosurveillance in the biliary tract