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

Three-dimensional DNA image cytometry by confocal scanning laser microscopy in thick tissue blocks of prostatic lesions

DNA ploidy provides important information for the evaluation of the prognosis of prostate cancer. For the purpose of DNA cytometry and nuclear measurements, we developed an image processing system for the acquisition and processing of three-dimensional (3D) images based on confocal scanning laser microscopy (CSLM). The advantage of the CSLM is the preservation of the tissue architecture and the possibility of multilabeling. It is possible to determine both individual nuclear features and cellular features and the degree of the spatial heterogeneity of several markers. Special attention was paid to the development of the automatic method for the 3D segmentation of cell nuclei. Thick tissue slides (100 μm), stained for DNA with chromomycin A3, from 4 patients (with benign hyperplasia, prostatic intraepithelial neoplasia (PIN), and well- and poorly-differentiated adenocarcinoma of the prostate), were studied in order to test the practicability of the developed methodology. DNA histograms showed a single peak in the diploid range for the hyperplasia and PIN cases. For the case of well-differentiated carcinoma, 2 peaks were observed, 1 in the diploid range and 1 in the tetraploid range. The case of poorly-differentiated carcinoma was characterized by an aneuploid distribution. For the cases of PIN and carcinomas, we observed a considerable variation of the volume of nuclei