Highly-parallelized simulation of a pixelated LArTPC on a GPU

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype

Morbilidad y mortalidad en una serie de pacientes con neoplasias del peritoneo, tratados con citorreducción peritoneal más quimioterapia hipertérmica intraperitoneal en el Hospital Universitario de la Fundación Santa Fe de Bogotá (ONCOLGroup - estudio ATIA)

Introducción: El procedimiento de peritonectomía radical seguida por quimioterapia intraperitoneal hipertérmica (HIPEC, Hyperthermic Intraperitoneal Chemotherapy), se considera el estándar de tratamiento para neoplasias del peritoneo. Objetivo: Evaluar varios desenlaces en una cohorte de pacientes con neoplasias del peritoneo tratados con HIPEC. Métodos: Se incluyeron 24 pacientes tratados en forma consecutiva con peritonectomía radical más HIPEC, entre noviembre de 2007 y julio de 2010. Quince (62%) tenían tumores de origen apendicular, 4 (16,7%) tumores primarios del peritoneo y el resto fueron 2 carcinomas de ovario, uno de colon, un carcinosarcoma y un hemangioendotelioma. La edad promedio fue 53 años (rango 26-68) y mediana de seguimiento 14,2 (1-32) meses. Se valoraron datos demográficos, histología, índice de carcinomatosis peritoneal (PCI), características de los procedimientos quirúrgicos y varios desenlaces como supervivencia libre de recaída (SLR) y global (SG). También se determinó la morbilidad y mortalidad a corto plazo. Resultados: En 18 (75%) se logró citorreducción completa. El PCI promedio fue 15 ( 10: 58%) y la mediana (rango) para el tiempo quirúrgico, estancia en UCI, duración del soporte nutricional y tiempo de estancia hospitalaria fueron de 12,5 (7-20) horas, 11,4 (2-74) días, 13,8 (12-65) días y 29,1 (10-90) días, respectivamente. Un paciente (4%) falleció, 6 meses después del procedimiento por múltiples complicaciones asociadas. Se observó morbilidad considerable en el 52% de los casos, incluyendo eventos tromboembólicos (41%), bacteremia relacionada con catéter (29%), fístulas (29%) y nefrotoxicidad (25%). Seis pacientes (25%) tuvieron recaída con una SLR de 21 meses. Conclusiones: La cirugía citorreductiva más HIPEC en pacientes bien seleccionados con neoplasias las cuales afectan el peritoneo, resulta un procedimiento que se puede realizar en Colombia con un adecuado perfil de seguridad y eficacia. La mortalidad fue similar a lo reportado en la literatura mundial

Supplementary Material for: Real-World Treatment Patterns, Survival, and Prediction of CNS Progression in ALK-Positive Non-Small-Cell Lung Cancer Patients Treated with First-Line Crizotinib in Latin America Oncology Practices

<b><i>Objective:</i></b> This study describes the real-world characteristics, treatment sequencing, and outcomes among Hispanic patients with locally advanced/metastatic ALK-positive non-small-cell lung cancer (NSCLC) treated with crizotinib. <b><i>Methods:</i></b> A retrospective patient review was conducted for several centers in Latin America. Clinicians identified ALK-positive NSCLC patients who received crizotinib and reported their clinical characteristics, treatments, and survival. Overall survival and progression-free survival (PFS) were described. A Random Forest Tree (RFT) model was constructed to predict brain progression. <b><i>Results:</i></b> A total of 73 patients were included; median age at diagnosis was 58 years, 60.3% were female, and 93.2% had adenocarcinoma. Eighty-nine percent of patients were never smokers/former smokers, 71.1% had ≥2 sites of metastasis, and 20.5% had brain metastases at diagnosis. The median PFS on first-line crizotinib was 7.07 months (95% CI 3.77–12.37) and the overall response rate was 52%. Of those who discontinued crizotinib, 55.9% progressed in the central nervous system (CNS). The RFT model reached a sensitivity of 100% and a specificity of 88% for prediction of CNS progression. <b><i>Conclusions:</i></b> The overall response rate and the PFS observed in Hispanic patients with ALK-positive NSCLC treated with first-line crizotinib were similar to those in previous reports. An RFT model is helpful in predicting CNS progression and can help clinicians tailor treatments in a resource-limited practice