Cocliques of maximal size in the prime graph of a finite simple group

In this paper we continue our investgation of the prime graph of a finite simple group started in http://arxiv.org/abs/math/0506294 (the printed version appeared in [1]). We describe all cocliques of maximal size for all finite simple groups and also we correct mistakes and misprints from our previous paper. The list of correction is given in Appendix of the present paper.Comment: published version with correction

Evaluation of Directive-Based GPU Programming Models on a Block Eigensolver with Consideration of Large Sparse Matrices

Achieving high performance and performance portability for large-scale scientific applications is a major challenge on heterogeneous computing systems such as many-core CPUs and accelerators like GPUs. In this work, we implement a widely used block eigensolver, Locally Optimal Block Preconditioned Conjugate Gradient (LOBPCG), using two popular directive based programming models (OpenMP and OpenACC) for GPU-accelerated systems. Our work differs from existing work in that it adopts a holistic approach that optimizes the full solver performance rather than narrowing the problem into small kernels (e.g., SpMM, SpMV). Our LOPBCG GPU implementation achieves a 2.8$${\times }$$–4.3$${\times }$$ speedup over an optimized CPU implementation when tested with four different input matrices. The evaluated configuration compared one Skylake CPU to one Skylake CPU and one NVIDIA V100 GPU. Our OpenMP and OpenACC LOBPCG GPU implementations gave nearly identical performance. We also consider how to create an efficient LOBPCG solver that can solve problems larger than GPU memory capacity. To this end, we create microbenchmarks representing the two dominant kernels (inner product and SpMM kernel) in LOBPCG and then evaluate performance when using two different programming approaches: tiling the kernels, and using Unified Memory with the original kernels. Our tiled SpMM implementation achieves a 2.9$${\times }$$ and 48.2$${\times }$$ speedup over the Unified Memory implementation on supercomputers with PCIe Gen3 and NVLink 2.0 CPU to GPU interconnects, respectively

An approach to hygiene education among rural Indian school going children

Objectives: To find out the prevalence of intestinal parasites and its epidemiological correlates among rural Indian school going (6-14 years) children and to study the effect of focused, need based child to child hygiene education on personal hygiene of school children. Materials and Methods: In September 2007, the present participatory action research was undertaken at a feasibly selected village Dhotra (Kasar) in Wardha district of central India. A triangulated research design of quantitative (survey) and qualitative (transect walk & pile sorting) methods was used for the needs assessment before initiating formal hygiene education. Out of enlisted 172 children, data of 118 children with complete information was used for final analysis. The quantitative and qualitative data was entered and analyzed using the Epi Info 6.04 software and Anthropac 4.98.1/X software package respectively. School based participatory life skills based child to child hygiene education was undertaken for message dissemination and behavior change. The effect of this hygiene education on identified key behaviors was assessed after one month Results: Out of the 118 (50 male and 68 female) subjects examined 21 (17.8%, 95%CI, 11.4 – 25.9%) had intestinal parasite infection. The prevalence of intestinal parasitic infection was significantly high among children having dirty untrimmed nails (47.4%, 95%CI, 30.9 – 64.1%) followed by those having poor hand washing practices (37.2%, 95%CI, 22.9 – 53.2%). One month after hygiene education, the proportion of children having practice of hand washing with soap after defecation significantly improved from 63.6 % to 78%. The proportion of clean and cut nails also improved from 67.8% to 80 % (p<0.05). Conclusions: The need based, focused, life skills based child to child hygiene education was effective for behavior change. An integrated approach of drug treatment and focused participatory hygiene education is required to control parasite load among rural Indian school going children

Molecular mechanism of MBX2319 inhibition of Escherichia coli AcrB multidrug efflux pump and comparison with other inhibitors

Efflux pumps of the resistance nodulation division (RND) superfamily, such as AcrB, make a major contribution to multidrug resistance in Gram-negative bacteria. The development of inhibitors of the RND pumps would improve the efficacy of current and next-generation antibiotics. To date, however, only one inhibitor has been cocrystallized with AcrB. Thus, in silico struc- ture-based analysis is essential for elucidating the interaction between other inhibitors and the efflux pumps. In this work, we used computer docking and molecular dynamics simulations to study the interaction between AcrB and the compound MBX2319, a novel pyranopyridine efflux pump inhibitor with potent activity against RND efflux pumps of Enterobacteriaceae species, as well as other known inhibitors (D13-9001, 1-[1-naphthylmethyl]-piperazine, and phenylalanylarginine-ß-naphthyl-amide) and the binding of doxorubicin to the efflux-defective F610A variant of AcrB. We also analyzed the binding of a sub- strate, minocycline, for comparison. Our results show that MBX2319 binds very tightly to the lower part of the distal pocket in the B protomer of AcrB, strongly interacting with the phenylalanines lining the hydrophobic trap, where the hydrophobic por- tion of D13-9001 was found to bind by X-ray crystallography. Additionally, MBX2319 binds to AcrB in a manner that is similar to the way in which doxorubicin binds to the F610A variant of AcrB. In contrast, 1-(1-naphthylmethyl)-piperazine and phenylalanylarginine-ß-naphthylamide appear to bind to somewhat different areas of the distal pocket in the B protomer of AcrB than does MBX2319. However, all inhibitors (except D13-9001) appear to distort the structure of the distal pocket, impairing the proper binding of substrates

On right conjugacy closed loops of twice prime order

The right conjugacy closed loops of order 2p, where p is an odd prime, are classified up to isomorphism.Comment: Clarified definitions, added some remarks and a tabl

Evolution of magnetic fields through cosmological perturbation theory

The origin of galactic and extra-galactic magnetic fields is an unsolved problem in modern cosmology. A possible scenario comes from the idea of these fields emerged from a small field, a seed, which was produced in the early universe (phase transitions, inflation, ...) and it evolves in time. Cosmological perturbation theory offers a natural way to study the evolution of primordial magnetic fields. The dynamics for this field in the cosmological context is described by a cosmic dynamo like equation, through the dynamo term. In this paper we get the perturbed Maxwell's equations and compute the energy momentum tensor to second order in perturbation theory in terms of gauge invariant quantities. Two possible scenarios are discussed, first we consider a FLRW background without magnetic field and we study the perturbation theory introducing the magnetic field as a perturbation. The second scenario, we consider a magnetized FLRW and build up the perturbation theory from this background. We compare the cosmological dynamo like equation in both scenarios

The relation between hemispheric lateralisation and measures of immune competence and adherence in Human Immunodeficiency Virus Type 1 (HIV-1)

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited - Copyright © 2012 Sumner et al

Light-harvesting superstructures of green plant chloroplasts lacking photosystems

"This is the peer reviewed version of the following article: Belgio, E., Ungerer, P., and Ruban, A. V. (2015) Light-harvesting superstructures of green plant chloroplasts lacking photosystems. Plant Cell Environ, 38: 2035–2047. doi: 10.1111/pce.12528.which has been published in final form at https://dx.10.1111/pce.12528. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.This work was supported by TheLeverhulme Trust and BBSRC research grants to A.V.R