Composite chiral metamaterials with negative refractive index and high values of the figure of merit

Cataloged from PDF version of article.A composite chiral metamaterial (CCMM) is designed and studied both numerically and experimentally. The CCMM is constructed by the combination of a continuous metallic wires structure and a purely chiral metamaterial (CMM) that consists of conjugated Rosettes. For the CMM, only very small, useful bands of negative index can be obtained for circularly polarized waves. These bands are all above the chiral resonance frequencies because of the high value of the effective parameter of relative permittivity epsilon. After the addition of the continuous metallic wires, which provide negative permittivity, the high value of epsilon can be partially compensated. Thus, a negative index band for the left circularly polarized wave that is below the chiral resonance frequency is obtained for the CCMM. At the same time, a negative index band for the right circularly polarized wave that is above the chiral resonance frequency is also obtained. Furthermore, both negative index bands correspond to the transmission peaks and have high values of the figure of merit. Therefore, the CCMM design that is proposed here is more suitable than the CMM for the construction of chiral metamaterials with a negative index. (C) 2012 Optical Society of Americ

Merits of organizational metrics in defect prediction: An industrial replication

Defect prediction models presented in the literature lack generalization unless the original study can be replicated using new datasets and in different organizational settings. Practitioners can also benefit from replicating studies in their own environment by gaining insights and comparing their findings with those reported. In this work, we replicated an earlier study in order to investigate the merits of organizational metrics in building defect prediction models for large-scale enterprise software. We mined the organizational, code complexity, code churn and pre-release bug metrics of that large scale software and built defect prediction models for each metric set. In the original study, organizational metrics were found to achieve the highest performance. In our case, models based on organizational metrics performed better than models based on churn metrics but were outperformed by pre-release metric models. Further, we verified four individual organizational metrics as indicators for defects. We conclude that the performance of different metric sets in building defect prediction models depends on the project’s characteristics and the targeted prediction level. Our replication of earlier research enabled assessing the validity and limitations of organizational metrics in a different context.This research is supported partially by TEKES N4S programme in Finland and in Canada

Shotgun metagenomic analysis of microbial communities from the Loxahatchee nature preserve in the Florida Everglades.

BackgroundCurrently, much is unknown about the taxonomic diversity and the mechanisms of methane metabolism in the Florida Everglades ecosystem. The Loxahatchee National Wildlife Refuge is a section of the Florida Everglades that is almost entirely unstudied in regard to taxonomic profiling. This short report analyzes the metagenome of soil samples from this Refuge to investigate the predominant taxa, as well as the abundance of genes involved in environmentally significant metabolic pathways related to methane production (nitrogen fixation and dissimilatory sulfite reduction).MethodsShotgun metagenomic sequencing using the Illumina platform was performed on 17 soil samples from four different sites within the Loxahatchee National Wildlife Refuge, and underwent quality control, assembly, and annotation. The soil from each sample was tested for water content and concentrations of organic carbon and nitrogen.ResultsThe three most common phyla of bacteria for every site were Actinobacteria, Acidobacteria, and Proteobacteria; however, there was variation in relative phylum composition. The most common phylum of Archaea was Euryarchaeota for all sites. Alpha and beta diversity analyses indicated significant congruity in taxonomic diversity in most samples from Sites 1, 3, and 4 and negligible congruity between Site 2 and the other sites. Shotgun metagenomic sequencing revealed the presence of biogeochemical biomarkers of particular interest (e.g., mrcA, nifH, and dsrB) within the samples. The normalized abundances of mcrA, nifH, and dsrB exhibited a positive correlation with nitrogen concentration and water content, and a negative correlation with organic carbon concentration.ConclusionThis Everglades soil metagenomic study allowed examination of wetlands biological processes and showed expected correlations between measured organic constituents and prokaryotic gene frequency. Additionally, the taxonomic profile generated gives a basis for the diversity of prokaryotic microbial life throughout the Everglades

Mutations in LAMB1 Cause Cobblestone Brain Malformation without Muscular or Ocular Abnormalities

Cobblestone brain malformation (COB) is a neuronal migration disorder characterized by protrusions of neurons beyond the first cortical layer at the pial surface of the brain. It is usually seen in association with dystroglycanopathy types of congenital muscular dystrophies (CMDs) and ocular abnormalities termed muscle-eye-brain disease. Here we report homozygous deleterious mutations in LAMB1, encoding laminin subunit beta-1, in two families with autosomal-recessive COB. Affected individuals displayed a constellation of brain malformations including cortical gyral and white-matter signal abnormalities, severe cerebellar dysplasia, brainstem hypoplasia, and occipital encephalocele, but they had less apparent ocular or muscular abnormalities than are typically observed in COB. LAMB1 is localized to the pial basement membrane, suggesting that defective connection between radial glial cells and the pial surface mediated by LAMB1 leads to this malformation

Ultrafast transient optical loss dynamics in exciton-plasmon nano-assemblies

We study the exciton-plasmon dynamics that lead to optical loss mitigation via ultrafast transient absorption spectroscopy (UTAS) on hybrid aggregates of core-shell quantum dots (QDs) and Au nanoparticles (NPs). We highlight that generating hot electrons in plasmonic NPs contributes to the transient differential absorption spectrum under optical excitation. The results suggest modifying the method of analyzing the transient absorption spectra of loss mitigated systems. Additionally, we investigate the effect of Electron Oscillation frequency-Phonon Resonance Detuning (EOPRD) on loss mitigation efficiency. Moreover, power dependent UTAS reveal a frequency pulling like effect in the transient bleach maximum towards the gain emission. We show that the appropriate choice of the pump wavelength and by changing the pump power we can conclusively prove the existence of loss mitigation using UTAS. Finally, we study the transient kinetics of hybrid gain-plasmon systems and report interesting hybrid transient kinetics. © 2017 The Royal Society of Chemistry

Differential Roles of Cardiomyocyte and Macrophage Peroxisome Proliferator–Activated Receptor γ in Cardiac Fibrosis

OBJECTIVE—Cardiac fibrosis is an important component of diabetic cardiomyopathy. Peroxisome proliferator–activated receptor γ (PPARγ) ligands repress proinflammatory gene expression, including that of osteopontin, a known contributor to the development of myocardial fibrosis. We thus investigated the hypothesis that PPARγ ligands could attenuate cardiac fibrosis

New SMARCA2 mutation in a patient with Nicolaides–Baraitser syndrome and myoclonic astatic epilepsy

We report a de novo SMARCA2 missense mutation discovered on exome sequencing in a patient with myoclonic astatic epilepsy, leading to reassessment and identification of Nicolaides–Baraitser syndrome. This de novo SMARCA2 missense mutation c.3721C>G, p.Gln1241Glu is the only reported mutation on exon 26 outside the ATPase domain of SMARCA2 to be associated with Nicolaides–Baraitser syndrome and adds to chromatin remodeling as a pathway for epileptogenesis. © 2016 The Authors. American Journal of Medical Genetics Part A published by Wiley Periodicals, Inc