- / -

- / -

No description available.

Made available in DSpace on 2014-10-09T12:48:41Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:04Z (GMT). No. of bitstreams: 1 09151.pdf: 3898995 bytes, checksum: c6107a524057a95f300eee8a635c6f1e (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Made available in DSpace on 2014-10-09T12:48:41Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:04Z (GMT). No. of bitstreams: 1 09151.pdf: 3898995 bytes, checksum: c6107a524057a95f300eee8a635c6f1e (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

M.Sc. (Information Technology) / Biometrics is a unique method used to identify humans by distinct biological characterises. In recent years biometrics are showing up everywhere from homes, workplaces, schools and banks. This identification method is rapidly replacing existing methods such as passwords since it offers a higher level of security compared to existing methods. Fingerprints are the most common biometric choice. However fingerprint biometrics is showing limitations. Since fingerprints are an external trait, it can be exposed to many situations (cuts, dirt, wear and tear, and skin conditions) that may impact the biometric captured. These factors can cause security and usability issues. There have been a number of successful attempts such as alteration of fingerprints and gummy fingers which are used to bypass fingerprint readers. An emerging biometric called finger-vein recognition was invented to overcome the issues that fingerprint biometrics have. Finger-vein recognition which is based on the vascular patterns that exist inside the finger, claim to have superior usability characteristics where less false acceptance or rejections occur. Since the finger-vein recognition is based on an internal trait it is assumed that external factors such as scars or even dirt will not affect the biometric collected. This dissertation aims to investigate the limitations of fingerprints and to determine whether finger-vein recognition can address these limitations. During the course of the dissertation applicable fields such as construction and mining will be identified for finger-vein recognition where fingerprint recognition has shown weakness. Together, fingerprint and finger-vein technologies will be used in a mining industry to perform minor experiments. The results of these experiments will be used to determine if finger-vein addresses the fundamental limitations of fingerprint biometrics in these industries. The main purposes of the dissertation will be to investigate finger-vein technology, the applicable fields and whether finger-vein recognition can solve the problems fingerprint recognition imposes in certain industries.

No description available.

Master of Science

Yes / Tumor progression alters the composition and physical properties of the extracellular matrix. Particularly, increased matrix stiffness has profound effects on tumor growth and metastasis. While endothelial cells are key players in cancer progression, the influence of tumor stiffness on the endothelium and the impact on metastasis is unknown. Through quantitative mass spectrometry, we find that the matricellular protein CCN1/CYR61 is highly regulated by stiffness in endothelial cells. We show that stiffness-induced CCN1 activates β-catenin nuclear translocation and signaling and that this contributes to upregulate N-cadherin levels on the surface of the endothelium, in vitro This facilitates N-cadherin-dependent cancer cell-endothelium interaction. Using intravital imaging, we show that knockout of Ccn1 in endothelial cells inhibits melanoma cancer cell binding to the blood vessels, a critical step in cancer cell transit through the vasculature to metastasize. Targeting stiffness-induced changes in the vasculature, such as CCN1, is therefore a potential yet unappreciated mechanism to impair metastasis. / Cancer Research UK (CRUK Beatson Institute C596/A17196, CRUK Glasgow Centre C596/A18076 and S.Z. C596/A12935)

In the present study alpha-receptor modulation of coronary flow and cardiac function was examined in exercising dogs, chronically instrumented to measure: circumflex blood flow velocity (CFV), heart rate (HR), global left ventricular function (LVP and dP/dt Max) and regional left ventricular function (%SL and dL/dt (s)max). During exercise, local adrenergic blockade was produced by intracoronary injection of 1.0 mg phentolamine ( anon-specific alpha-antagonist) or .5 mp prazosin. Exercise significantly increased HR, LVP, dP/dt max, CFV, %SL and dL/dt (s)max. Neither alpha-antagonist produced changes in HR, LVP or %SL; however, both phentolamine and prazosin produced significant increses in dP/dtmax, CFV and dL/dt(s)max of the alpha-blocked region, when compared to their exercise level before alpha-blockade. It is suggested that an alpha1-adrenergic vasoconstriction limits coronary vasodilation and, thereby, cardiac function during exercise.