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

SUITABILITY OF DUCKWEED (Lemna minor) AS FEED FOR FISH IN POLYCULTURE SYSTEM

In the present study, we conducted an experiment to evaluate the effects of duckweed (Lemna minor) as feed on fish production in polyculture. The experiment had 2 treatments where in treatment 1 (T1) ponds were supplied with duckweed as feed and in treatment 2 (T2) ponds were kept as control (without supply of duckweed). Average survival rates in T1 and T2 were 90 and 89%, respectively. The specific growth rates (SGR) were higher in T1. Calculated net production in T1 was 6.25 tons ha.-1 yr.-1 and in T2 was 2.84 tons ha.-1 yr.-1 . The ranges of physico-chemical parameters analyzed were within the productive limit and more or less similar in all the ponds under both treatments during the experimental period. There were 24 genera of phytoplankton under 5 major groups and 10 genera of zooplankton under 3 major groups found in the experimental ponds. The net production in T1 was significantly higher than that of T2 indicated the use of duckweed as feed for fishes is economically sustainable in polyculture

Frozen-State Hierarchical Annealing

Abstract. There is growing demand for methods to synthesize large im-ages of porous media. Binary porous media generally contain structures with a wide range of scales. This poses difficulties for generating accu-rate samples using statistical techniques such as simulated annealing. Hierarchical methods have previously been found quite effective for such problems. In this paper, a frozen-state approach to hierarchical anneal-ing is presented that offers over an order of magnitude reduction in com-putational complexity versus existing hierarchical techniques. Current limitations to this approach and areas of further research are discussed.

Occurrence and characterization of multidrugresistant new delhi metallo-β-lactamase-1- producing bacteria isolated between 2003 and 2010 in Bangladesh

The purpose of this study was to screen for reduced susceptibility against imipenem and the presence of the New Delhi metallo-β-lactamase-1 (NDM-1) gene in a collection of Enterobacteriaceae (Escherichia coli, Shigella spp. and Klebsiella pneumoniae) from different surveillance studies between 2003 and 2010 at the International Centre for Diarrhoeal Disease Research, Bangladesh. None of the E. coli (n51789) and Shigella spp. (n590) isolated between 2009 and 2010 from stool samples was resistant or had intermediate susceptibility to imipenem. Among 127 extended-spectrum β-lactamase-producing strains isolated during 2003-2009, three Klebsiella pneumoniae isolates (2.4 %) were resistant to imipenem and were positive for blaNDM-1. All these NDM-1-producing strains were isolated in 2008 and were resistant to all antibiotics tested except for tigecycline and colistin. All three isolates were positive for blaOXA-1 group, blaCTX-M-1 group (blaCTX-M-15) and blaSHV genes, whilst two isolates were positive for 16S rRNA methylase (armA) and qnr (qnrB) genes. One isolate was positive for the blaCMY gene and one for the rmtB gene. The blaNDM-1 gene was located on a conjugative plasmid of