Development and Control of a Real Spherical Robot.

This paper presents the design and implementation of a spherical robot with an internal mechanism based on a pendulum. The design is based on significant improvements made, including an electronics upgrade, to a previous robot prototype developed in our laboratory. Such modifications do not significantly impact its corresponding simulation model previously developed in CoppeliaSim, so it can be used with minor modifications. The robot is incorporated into a real test platform designed and built for this purpose. As part of the incorporation of the robot into the platform, software codes are made to detect its position and orientation, using the system SwisTrack, to control its position and speed. This implementation allows successful testing of control algorithms previously developed by the authors for other robots such as Villela, the Integral Proportional Controller, and Reinforcement Learning.

Modeling and Control of a Spherical Robot in the CoppeliaSim Simulator.

This article presents the development of a model of a spherical robot that rolls to move and has a single point of support with the surface. The model was developed in the CoppeliaSim simulator, which is a versatile tool for implementing this kind of experience. The model was tested under several scenarios and control goals (i.e., position control, path-following and formation control) with control strategies such as reinforcement learning, and Villela and IPC algorithms. The results of these approaches were compared using performance indexes to analyze the performance of the model under different scenarios. The model and examples with different control scenarios are available online.

Detection of human papillomavirus and relevant tumor suppressors and oncoproteins in laryngeal tumors.

PURPOSE: The mechanism of larynx oncogenesis is complex and controlled by various factors, most of them involved in cell proliferation and apoptosis. In this study, we evaluated the levels of two suppressor proteins (pRb and p53) and two oncogenic proteins (c-Myc and Bcl-2), as well as the apoptotic levels and the presence of human papillomavirus (HPV) in both tumor types. EXPERIMENTAL DESIGN: Low- or high-risk HPV viral DNA was determined by PCR and in situ PCR; the level of cellular proteins was examined by immunohistochemistry; the presence of apoptotic cells was evaluated by in situ cell death detection. RESULTS: Most laryngeal papillomatosis samples contained low-risk HPV determined by both techniques. However, 25% of laryngeal carcinoma samples were positive for HPV employing PCR or in situ PCR. In papillomatosis, pRb and p53 levels were higher than in normal larynxes, whereas laryngeal cancer presented the lowest levels. c-Myc oncogene expression was very low in normal and cancer tissues but highly increased in papillomatosis. Bcl-2 expression was low and showed no significant difference between laryngeal papillomatosis and normal larynxes. By contrast, Bcl-2 was clearly up-regulated in cancer. Normal larynx samples and those from laryngeal papillomatosis exhibited similar relatively high numbers of apoptotic cells, whereas in malignant tumors, these cells were scarce. CONCLUSION: Our results suggest that HPV is an important risk factor in papillomatosis and in some malignant larynx tumors with a strong participation of cellular genes, specifically involved in proliferation and apoptosis. In benign papillomatosis lesions but not in larynx cancer, high p53 activity might preserve the apoptosis process. In larynx cancer, low p53 levels and high bcl-2 expression may be playing an important role to block apoptosis.

[Analysis of Bcr-abl type transcript and its relationship with platelet count in Mexican patients with chronic myeloid leukemia]. / Análisis del tipo de transcrito bcr-abl y su relación con la cuenta plaquetaria en pacientes mexicanos con leucemia mieloide crónica.

PROBLEM: It has been suggested that type of chimeric mRNA is associated with differences in the clinical and hematologic characteristics of chronic myeloid leukemia (CML). However, prognostic value of type of chimeric mRNA bcr-xabl (b3a2 or b2a2) is still controversial. METHODS: We analyzed 97 cases of Philadelphia-positive CML to determine mRNA type by reverse-polymerase chain reaction (RT-PCR) and its relationship with clinical features. RESULTS: We detected b3a2 bcr-abl transcripts in 27 (28%) cases, b2a2 in 57 (59%) cases, and 13 (13%) with both mRNA transcripts b3a2/b2a2. These frequencies were the total reverse of other reports. Age, sex, hemoglobin, and white-cell counts showed no significant difference for those with either b3a2 or b2a2 bcr-abl transcripts. However, platelet counts of b3a2 patients were significantly higher than those of b2a2 patients (743.3 vs 477.3 x 109/L; p = 0.01). In addition, in the subgroup of patients whose white-cell count at diagnosis was < 100 x 10(9)/L, those with b3a2 transcript had a significantly higher platelet count (679.1 vs. 352.2 x 10(9)/L; p = 0.001). CONCLUSIONS: We observed reversed frequency of bcr-abl transcripts in this population, but agreement with other Latin-American reports. In addition, our data suggested that there is different CML biological behavior in our population and that there is a subpopulation of CML patients in whom b3a2 is associated witH higher thrombopoietic activity.