Loc-NeRF: Monte Carlo Localization using Neural Radiance Fields

We present Loc-NeRF, a real-time vision-based robot localization approach that combines Monte Carlo localization and Neural Radiance Fields (NeRF). Our system uses a pre-trained NeRF model as the map of an environment and can localize itself in real-time using an RGB camera as the only exteroceptive sensor onboard the robot. While neural radiance fields have seen significant applications for visual rendering in computer vision and graphics, they have found limited use in robotics. Existing approaches for NeRF-based localization require both a good initial pose guess and significant computation, making them impractical for real-time robotics applications. By using Monte Carlo localization as a workhorse to estimate poses using a NeRF map model, Loc-NeRF is able to perform localization faster than the state of the art and without relying on an initial pose estimate. In addition to testing on synthetic data, we also run our system using real data collected by a Clearpath Jackal UGV and demonstrate for the first time the ability to perform real-time global localization with neural radiance fields. We make our code publicly available at https://github.com/MIT-SPARK/Loc-NeRF

Modulation of aldose reductase activity by aldose hemiacetals

Glucose is considered as one of the main sources of cell damage related to aldose reductase (AR) action in hyperglycemic conditions and a worldwide effort is posed in searching for specific inhibitors of the enzyme. This AR substrate has often been reported as generating non-hyperbolic kinetics, mimicking a negative cooperative behavior. This feature was explained by the simultaneous action of two enzyme forms acting on the same substrate

Centro Educativo Inclusivo para Niños y Adolescentes de 06 a 16 años con discapacidad física y sensorial. Caso distrito de Comas, 2019

La presente tesis está orientada a investigar y desarrollar la propuesta de un Centro Educativo Inclusivo para niños y adolescentes de 06 a 16 años con discapacidad Física y Sensorial, que posean espacios y ambientes adecuados, destinados al desarrollo de aprendizaje como estrategia de solución a la problemática existente en el distrito de Comas, esta problemática se forma debido a la inexistencia de Centros Educativos que permitan una adecuada formación educativa a los niños y adolescentes con discapacidad. El estudio de esta tesis se basa en el planteamiento de un Centro Educativo Inclusivo en el distrito de Comas, lugar donde existe gran porcentaje de niños y adolescentes que padecen limitaciones físicas y sensoriales, además de ello se estudia las características y deficiencias del distrito, la programación arquitectónica del equipamiento educativo, el terreno en el que se implantará el centro y finalmente el estudio de la propuesta como objeto arquitectónico que a futuro será un Centro Educativo Inclusivo que logre abarcar a una gran cantidad de alumnos con limitaciones y poder ayudar a su desarrollo intelectual. El objetivo principal de esta tesis es dar solución a esta problemática; planteando el diseño de un Centro Educativo Inclusivo que posea particulares características que potencien el uso de espacios, accesibilidad neutral y adecuada funcionalidad. Para la realización esta investigación, se hizo uso de las estadísticas y de la encuesta, llevando a cabo la confiabilidad del instrumento mediante el alfa de cronbach, y la contratación de hipótesis mediante el método estadística de Rho de Spearman

Psychological Stress and Cancer: New Evidence of An Increasingly Strong Link

To date stress, a highly complex process that disrupts homeostasis and involves environmental and psychosocial factors, is considered as one of the most crucial factor that affects our daily life, especially urban dweller's life. Clinical and experimental studies widely support the notion that adrenergic stimulation due to chronic stress affects inflammation and metabolism. In this work, supported by several recent scientific evidences, we show how stress plays a positive role in cancer initiation, progression and cancer metastasis, a negative role for anti-tumor immune function and therapy response. Understanding the intricacies of this interaction could provide an additional help on how act in cancer prevention and therap

Optimal Ki67 cut-off for luminal breast cancer prognostic evaluation: a large case series study with a long-term follow-up

Although Ki67 index suffers from poor reproducibility, it is one of the most important prognostic markers used by oncologists to select the treatment of estrogen receptor (ER) positive breast cancer patients. In this study, we aim to establish the optimal Ki67 cut-offs for stratifying patient prognosis and to create a comprehensive prognostic index for clinical applications. A mono-institutional cohort of 1.577 human epidermal growth factor receptor 2 negative/ER+ breast cancer patients having complete clinical, histological, and follow-up data was collected. The 14 and 20 % Ki67 cut-offs were correlated to disease-free interval (DFI) and disease-specific survival (DSS). To create a comprehensive prognostic index, we used independent variables selected by uni/multivariate analyses. In terms of DFI and DSS, patients bearing tumors with Ki67 < 14 % proliferation index did not differ from those with Ki67 values between 14 and 20 %. Patients with tumor with Ki67 > 20 % showed the poorest prognosis. Moreover, to tumor size, the number of metastatic lymph nodes and Ki67 > 20 % was given a score value, varying depending on definite cut-offs and used to create a prognostic index, which was applied to the population. Patients with a prognostic index ≥3 were characterized by significant risk of relapse [DFI: Hazard Ratio (HR) = 4.74, p < 0.001] and death (DSS: HR = 5.03, p < 0.001). We confirm that the 20 % Ki67 cut-off is the best to stratify high-risk patients in luminal breast cancers, and we suggest to integrate it with other prognostic factors, to better stratify patients at risk of adverse outcome

non invasive methods for the assessment of hepatic fibrosis transient elastography hyaluronic acid 13c aminopyrine breath test and cytokeratin 18 fragment

Background. In the management of chronic hepatitis C (CHC) patients, liver biopsy is the gold standard for liver fibrosis assessment despite some technical limits and risks. Non-invasive approaches have been proposed as alternative methods to evaluate structural liver damage. Aim. To investigate the diagnostic accuracy of transient elastography, 13C-aminopyrine breath test ( 13 C-ABT), serum hyaluronic acid (HA) and cytokeratin 18 Asp396 fragment (CK-18) as non-invasive methods of liver fibrosis assessment ad their correlation to METAVIR score. Material and methods. In a cohort of 57 CHC patients, liver stiffness, cumulative percentage of administered dose of 13C-aminopyrine at 120 min, serum HA and serum CK-18 concentration were determined. Diagnostic accuracy in detecting significant fibrosis (F ≥ 2), severe fibrosis (F ≥ 3) and cirrhosis (F = 4) was assessed by the area under the receiver operating characteristic curve. Results. Liver fibrosis score showed a strong correlation with liver stiffness (r = 0.667; p < 0.0001) and a significant inverse correlation with 13C-ABT results (r = -0.418; p = 0.0012). A weaker correlation was found with CK18 (r = 0.329; p = 0.0126) and no correlation with HA. Areas under the curve of elastography, 13C-ABT, HA and CK18 were: 0.98, 0.75, 0.69, 0.64, respectively, for F ≥ 2; 0.97, 0.69, 0.80, 0.66, respectively, for F ≥ 3; 0.95, 0.64, 0.70, 0.56, respectively, for F = 4. Conclusion. Elastography has the best diagnostic accuracy for the assessment of the degree of liver fibrosis in CHC patients. Its application can provide an alternative useful tool for monitoring the disease evolution