Lagrange Anchor for Bargmann-Wigner equations

A Poincare invariant Lagrange anchor is found for the non-Lagrangian relativistic wave equations of Bargmann and Wigner describing free massless fields of spin s > 1/2 in four-dimensional Minkowski space. By making use of this Lagrange anchor, we assign a symmetry to each conservation law.Comment: A contribution to Proceedings of the XXXI Workshop on the Geometric Methods in Physic

An Efficient Data Structure for Dynamic Two-Dimensional Reconfiguration

In the presence of dynamic insertions and deletions into a partially reconfigurable FPGA, fragmentation is unavoidable. This poses the challenge of developing efficient approaches to dynamic defragmentation and reallocation. One key aspect is to develop efficient algorithms and data structures that exploit the two-dimensional geometry of a chip, instead of just one. We propose a new method for this task, based on the fractal structure of a quadtree, which allows dynamic segmentation of the chip area, along with dynamically adjusting the necessary communication infrastructure. We describe a number of algorithmic aspects, and present different solutions. We also provide a number of basic simulations that indicate that the theoretical worst-case bound may be pessimistic.Comment: 11 pages, 12 figures; full version of extended abstract that appeared in ARCS 201

Nutrition and public hygiene among children under five years of age in Mukuru slums of Makadara division, Nairobi

Objective: To determine the relationship between sanitation and malnutrition among children below five years. Design: A random sampling followed by an experimental design on microbiological analysis of food and water samples. Setting: Mukuru slums of Makadara division in Nairobi City. Subjects: Eighty food and thirty water samples from households within the study area were used. Results: Poor food and personal hygiene were observed within the households in the study area. Most of the respondents did not practice hygienic methods during food handling such as washing hands and vegetables before preparation. Food especially the leftovers was served at ambient temperatures. Sneezing and coughing over food during preparation were also a common practice which exposed consumers to contamination, Garbage disposal and proper drainage were also poor deepening on the sanitation problem. Microbiological analysis of water and food revealed that Escherichia coli (E-coli) and Salmonella spp. pathogens which are known causes of diarrhoea in children under five years of age. Conclusion: Poor hygienic and unsanitary practices are major causes of diarrhoea, hence malnutrition in crowded Mukuru slums of Nairobi City.East African Medical Journal Vol. 85 (8) 2008: pp. 386-39

Local Moment Instability of Os in Honeycomb Li2.15Os0.85O3.

Compounds with honeycomb structures occupied by strong spin orbit coupled (SOC) moments are considered to be candidate Kitaev quantum spin liquids. Here we present the first example of Os on a honeycomb structure, Li2.15(3)Os0.85(3)O3 (C2/c, a = 5.09 Å, b = 8.81 Å, c = 9.83 Å, β = 99.3°). Neutron diffraction shows large site disorder in the honeycomb layer and X-ray absorption spectroscopy indicates a valence state of Os (4.7 ± 0.2), consistent with the nominal concentration. We observe a transport band gap of Δ = 243 ± 23 meV, a large van Vleck susceptibility, and an effective moment of 0.85 μB, much lower than expected from 70% Os(+5). No evidence of long range order is found above 0.10 K but a spin glass-like peak in ac-susceptibility is observed at 0.5 K. The specific heat displays an impurity spin contribution in addition to a power law ∝T(0.63±0.06). Applied density functional theory (DFT) leads to a reduced moment, suggesting incipient itineracy of the valence electrons, and finding evidence that Li over stoichiometry leads to Os(4+)-Os(5+) mixed valence. This local picture is discussed in light of the site disorder and a possible underlying quantum spin liquid state

Undoped gallium antimonide studied by positron annihilation spectroscopy

Positron lifetime spectroscopy has been used to study the vacancy type defects in undoped gallium antimonide. Temperature dependent positron trapping into the VGarelated defect having a characteristic lifetime of 310ps was observed in the as-grown sample. The lifetime data were well described by a model involving the thermal ionization (0/-) of the VGa-related defect and its ionization energy was found to be E(0/)=83meV. For the electron irradiated sample, the VGa-related defect with lifetime of 310ps that was found in the non-irradiated samples was also identified. Moreover, another lifetime component (280ps) was only observed in the electron irradiated sample but not in the non-irradiated sample. It was also attributed to the V Ga-related defect. The two identified VGa-related defects should have different microstructures because of their difference in characteristic lifetimes. The 280ps component remains thermally stable after the 500°C annealing while the 310ps component anneals at 300°C.published_or_final_versio

Banger-related ocular injuries during New Year festivities in Osogbo, SW Nigeria

BACKGROUND: Different types of ocular injuries could be sustained following banger explosives. This case report could be the first of such reports in West Africa.CASE DETAILS: We report cases of ocular injuries caused by bangers. This was a hospital-based study of 3 consecutive cases that presented during the New Year festival. Injuries were classified according to Birmingham eye trauma terminology system (BETTS). Two of the patients ended up with irreversible loss of vision. Another two of the three were bystanders.CONCLUSION: As banger-related ocular injuries result in significant morbidity, public education regarding the proper use of bangers would help in preventing the incidence of ocular injuries and blindness. Advocacy for a strict legislation to regulate its use is strongly recommended.KEYWORDS: Bangers, eye injuries, holidays, Nigeri

3DQ: Compact Quantized Neural Networks for Volumetric Whole Brain Segmentation

Model architectures have been dramatically increasing in size, improving performance at the cost of resource requirements. In this paper we propose 3DQ, a ternary quantization method, applied for the first time to 3D Fully Convolutional Neural Networks (F-CNNs), enabling 16x model compression while maintaining performance on par with full precision models. We extensively evaluate 3DQ on two datasets for the challenging task of whole brain segmentation. Additionally, we showcase our method's ability to generalize on two common 3D architectures, namely 3D U-Net and V-Net. Outperforming a variety of baselines, the proposed method is capable of compressing large 3D models to a few MBytes, alleviating the storage needs in space critical applications.Comment: Accepted to MICCAI 201

Bubble transport by electro-magnetophoretic forces at anode bottom of aluminium cells

Electrically conducting and nonconducting particles and bubbles experience additional forcing in a liquid which carries electric current. These so called electro-magnetophoretic forces are well known in metallurgical applications, like metal purification in vacuum-arc remelting, electro-slag processes, impurity removal or concentration change in special castings. However, the effect of electro-magnetophoretic forces has never been considered for aluminium cells where the gas bubbles evolving in the liquid electrolyte are surrounded by an electric current and significant magnetic fields. We present models to estimate the effect of electric current flow in the vicinity of the bubbles and the additional pressure distribution resulting from the magnetic forces in the surrounding liquid electrolyte. According to the estimates, this force becomes important for bubbles exceeding 2 mm in size, and could be sufficient to overcome the typical drag force associated with electrolyte flow thereby opposing motion of the bubble along the base of the anode when it is inclined at a slight angle. The effect could explain certain features of the anode effect onset. Mathematical models and numerical results are presented and a further implementation in the general MHD code for the aluminium cell design is discussed

Organelles genome stability of wheat plantlets produced by anther culture

Plantlets derived from in vitro culture might exhibit somoclonal variation which is often heritable, and molecular variations may be generated in vitro. Since the direction of most studies is toward nuclear genome, there is a little known about the DNA of organelles. This study was conducted to test the genetic stability of wheat organelles genomes for plantlets produced by anther culture using restriction fragment length polymorphism (RFLP) analyses. One of the intergenic regions of cpDNA and one of mtDNA introns were amplified with polymerase chain reaction (PCR). The PCR products were then sequenced and digested with four restriction endonucleases (EcoR1, BamH1, NdeI and Sac1). The amplified product from cpDNA was 1000 bp in size, and digested only with NdeI into two bands with 650 and 350 bp. The amplified product from mtDNA was 1550 bp in size, and digested only with Sac1 into two bands with 1220 and 330 bp. The results obtained showed that no noticeable difference can be detected between doubled haploid plantlets and parental plants at the level of ctDNA and mtDNA organization. It can be concluded that in vitro culture by itself does not systematically generate a cytoplasmic variation in plant cells.Key words: RFLP analysis, wheat plantlets, wheat anther culture, doubled haploids, genetic stability, mitochondria and chloroplast genome