We study holomorphic flows on Stein manifolds. We prove that a holomorphic flow with isolated sin... more We study holomorphic flows on Stein manifolds. We prove that a holomorphic flow with isolated singularities and a dicritical singularity of the form $\sum^{n}_{j=1}\lambda_{j}z_{j}\frac{\partial}{\partial z_{j}}+\ldots, \lambda_{j}\in \mathbb{Q}_{+},\forall j \in \{1,\ldots,n\}$ on a Stein manifold $M^n, n \geq 2$ with ${\mathop{H}\limits^{\vee}}{^{2}}(M^{n}, {{{\mathbb{Z}}}})=0$ , is globally analytically linearizable; in particular M is biholomorphic to ${\mathbb{C}}^{n}$ . A complete stability result for periodic orbits is also obtained.
Abstract – Imaging plays an essential role in the evaluation of maxillofacial fractures both pre... more Abstract – Imaging plays an essential role in the evaluation of maxillofacial fractures both pre- and postoperatively. Several studies support the use of conventional two-dimensional imaging for traumas involving mainly the mandible, but for more complex situations advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging have higher indication. Nowadays, besides CT, cone-beam computed tomography (CBCT) has appeared as a reasonable and reliable alternative considering radiation dosage, image quality and comfort for the patient. The purpose of this study was to review the fracture patterns involving the maxillofacial complex, provide a technical and practical comparison between CT and CBCT, and finally present the potential applications of CBCT illustrated with clinical examples.
Introduction: The aim of this study was to determine the diagnostic accuracy of 2 cone-beam compu... more Introduction: The aim of this study was to determine the diagnostic accuracy of 2 cone-beam computed tomography (CBCT) machines and periapical (PA) radiography in detecting simulated apical lesions created with the smallest dental burs available. Methods: By using mandibles from human cadavers, simulated apical lesions were created and then progressively enlarged in 16 roots by using sizes #1/4, #1/2, #1, #2, #4, and #6 round burs. Imaging was obtained after each enlargement with a Kodak 9000 3D (Kodak) CBCT, a Veraviewpocs 3De (Morita) CBCT, and intraoral digital PA radiography. Specificity and sensitivity at variable decision thresholds were calculated and plotted on receiver operator characteristic curves. The area under the curve (AUC) served as an estimate of diagnostic accuracy. Results: The overall AUCs for Kodak, Morita, and PA radiography were 0.767 (95% confidence interval [CI], 0.743-0.792), 0.753 (95% CI, 0.728-0.779), and 0.584 (95% CI, 0.554-0.615), respectively. The AUCs for Kodak and Morita were both statistically significantly larger than the AUC for all corresponding simulated lesion sizes imaged with PA radiography. Between Kodak and Morita, there were no statistically significant differences in AUCs for any of the corresponding simulated lesion sizes. Conclusions: Both CBCT devices demonstrated poor accuracy in detecting simulated lesions smaller than 0.8 mm in diameter, fair to good accuracy when simulated lesion diameter was between 0.8-1.4 mm, and excellent accuracy when simulated lesions were larger than 1.4 mm in diameter. PA radiography, at best, demonstrated poor diagnostic accuracy for all simulated lesion sizes. (J Endod 2012;38:965-970)
We study holomorphic flows on Stein manifolds. We prove that a holomorphic flow with isolated sin... more We study holomorphic flows on Stein manifolds. We prove that a holomorphic flow with isolated singularities and a dicritical singularity of the form $\sum^{n}_{j=1}\lambda_{j}z_{j}\frac{\partial}{\partial z_{j}}+\ldots, \lambda_{j}\in \mathbb{Q}_{+},\forall j \in \{1,\ldots,n\}$ on a Stein manifold $M^n, n \geq 2$ with ${\mathop{H}\limits^{\vee}}{^{2}}(M^{n}, {{{\mathbb{Z}}}})=0$ , is globally analytically linearizable; in particular M is biholomorphic to ${\mathbb{C}}^{n}$ . A complete stability result for periodic orbits is also obtained.
Abstract – Imaging plays an essential role in the evaluation of maxillofacial fractures both pre... more Abstract – Imaging plays an essential role in the evaluation of maxillofacial fractures both pre- and postoperatively. Several studies support the use of conventional two-dimensional imaging for traumas involving mainly the mandible, but for more complex situations advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging have higher indication. Nowadays, besides CT, cone-beam computed tomography (CBCT) has appeared as a reasonable and reliable alternative considering radiation dosage, image quality and comfort for the patient. The purpose of this study was to review the fracture patterns involving the maxillofacial complex, provide a technical and practical comparison between CT and CBCT, and finally present the potential applications of CBCT illustrated with clinical examples.
Introduction: The aim of this study was to determine the diagnostic accuracy of 2 cone-beam compu... more Introduction: The aim of this study was to determine the diagnostic accuracy of 2 cone-beam computed tomography (CBCT) machines and periapical (PA) radiography in detecting simulated apical lesions created with the smallest dental burs available. Methods: By using mandibles from human cadavers, simulated apical lesions were created and then progressively enlarged in 16 roots by using sizes #1/4, #1/2, #1, #2, #4, and #6 round burs. Imaging was obtained after each enlargement with a Kodak 9000 3D (Kodak) CBCT, a Veraviewpocs 3De (Morita) CBCT, and intraoral digital PA radiography. Specificity and sensitivity at variable decision thresholds were calculated and plotted on receiver operator characteristic curves. The area under the curve (AUC) served as an estimate of diagnostic accuracy. Results: The overall AUCs for Kodak, Morita, and PA radiography were 0.767 (95% confidence interval [CI], 0.743-0.792), 0.753 (95% CI, 0.728-0.779), and 0.584 (95% CI, 0.554-0.615), respectively. The AUCs for Kodak and Morita were both statistically significantly larger than the AUC for all corresponding simulated lesion sizes imaged with PA radiography. Between Kodak and Morita, there were no statistically significant differences in AUCs for any of the corresponding simulated lesion sizes. Conclusions: Both CBCT devices demonstrated poor accuracy in detecting simulated lesions smaller than 0.8 mm in diameter, fair to good accuracy when simulated lesion diameter was between 0.8-1.4 mm, and excellent accuracy when simulated lesions were larger than 1.4 mm in diameter. PA radiography, at best, demonstrated poor diagnostic accuracy for all simulated lesion sizes. (J Endod 2012;38:965-970)
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