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SUMMARY: Brassica carinata (BBCC) commonly referred to as Ethiopian mustard is a natural allotetraploid containing the genomes of Brassica nigra (BB) and Brassica oleracea (CC). It is an oilseed crop endemic to the northeastern regions of Africa. Although it is under limited cultivation, B. carinata is valuable as it is resistant/highly tolerant to most of the pathogens affecting widely cultivated Brassica species of the U's triangle. We report a chromosome‐scale genome assembly of B. carinata accession HC20 using long‐read Oxford Nanopore sequencing and Bionano optical maps. The assembly has a scaffold N50 of ~39.8 Mb and covers ~1.11 Gb of the genome. We compared the long‐read genome assemblies of the U's triangle species and found extensive gene collinearity between the diploids and allopolyploids with no evidence of major gene losses. Therefore, B. juncea (AABB), B. napus (AACC), and B. carinata can be regarded as strict allopolyploids. We cataloged the nucleotide‐binding and leucine‐rich repeat immune receptor (NLR) repertoire of B. carinata and, identified 465 NLRs, and compared these with the NLRs in the other Brassica species. We investigated the extent and nature of early‐generation genomic interactions between the constituent genomes of B. carinata and B. juncea in interspecific crosses between the two species. Besides the expected recombination between the constituent B genomes, extensive homoeologous exchanges were observed between the A and C genomes. Interspecific crosses, therefore, can be used for transferring disease resistance from B. carinata to B. juncea and broadening the genetic base of the two allotetraploid species. Significance Statement: We report a highly contiguous genome assembly of allotetraploid mustard Brassica carinata HC20 (BBCC) which contains resistance to many diseases affecting the other extensively cultivated Brassica species of the U's triangle. Comparative analyses of the long‐read assemblies of the six Brassica species revealed high gene collinearity between the three diploid and their allotetraploid species. We tracked the early‐generation genomic interactions between the subgenomes of B. carinata (BBCC) and B. juncea (AABB) in their interspecific crosses using molecular karyotyping and proposed strategies to utilize this information for genomic introgressions. [ABSTRACT FROM AUTHOR]

Summary: Brassica juncea (AABB), commonly referred to as mustard, is a natural allopolyploid of two diploid species—B. rapa (AA) and B. nigra (BB). We report a highly contiguous genome assembly of an oleiferous type of B. juncea variety Varuna, an archetypical Indian gene pool line of mustard, with ~100× PacBio single‐molecule real‐time (SMRT) long reads providing contigs with an N50 value of >5 Mb. Contigs were corrected for the misassemblies and scaffolded with BioNano optical mapping. We also assembled a draft genome of B. nigra (BB) variety Sangam using Illumina short‐read sequencing and Oxford Nanopore long reads and used it to validate the assembly of the B genome of B. juncea. Two different linkage maps of B. juncea, containing a large number of genotyping‐by‐sequencing markers, were developed and used to anchor scaffolds/contigs to the 18 linkage groups of the species. The resulting chromosome‐scale assembly of B. juncea Varuna is a significant improvement over the previous draft assembly of B. juncea Tumida, a vegetable type of mustard. The assembled genome was characterized for transposons, centromeric repeats, gene content and gene block associations. In comparison to the A genome, the B genome contains a significantly higher content of LTR/Gypsy retrotransposons, distinct centromeric repeats and a large number of B. nigra specific gene clusters that break the gene collinearity between the A and the B genomes. The B. juncea Varuna assembly will be of major value to the breeding work on oleiferous types of mustard that are grown extensively in south Asia and elsewhere. [ABSTRACT FROM AUTHOR]

The development of more productive crops will be key to addressing the challenges that climate change, population growth and diminishing resources pose to global food security. Advanced 'omics techniques can help to accelerate breeding by facilitating the identification of genetic markers for use in marker‐assisted selection. Here, we present the validation of a new Associative Transcriptomics platform in the important oilseed crop Brassica juncea. To develop this platform, we established a pan‐transcriptome reference for B. juncea, to which we mapped transcriptome data from a diverse panel of B. juncea accessions. From this panel, we identified 355 050 single nucleotide polymorphism variants and quantified the abundance of 93 963 transcripts. Subsequent association analysis of functional genotypes against a number of important agronomic and quality traits revealed a promising candidate gene for seed weight, BjA.TTL, as well as additional markers linked to seed colour and vitamin E content. The establishment of the first full‐scale Associative Transcriptomics platform for B. juncea enables rapid progress to be made towards an understanding of the genetic architecture of trait variation in this important species, and provides an exemplar for other crops. Significance Statement: We present the development of a new pan‐transcriptome reference for Brassica juncea, and the establishment of an Associative Transcriptomics platform for dissecting the genetic architecture of complex traits in this crop, which provides a valuable resource for molecular breeding in B. juncea. We validate this platform by identifying and testing predictive marker associations for important quality traits; seed size, seed colour and γ‐tocopherol content. [ABSTRACT FROM AUTHOR]

In this article, a compact quad notched CPW fed ultrawideband (UWB) antenna of the size 35.4 × 26.6 × 1.6 mm3 with improved gain characteristic is proposed. The designed antenna has bandwidth ranging from 2.85 GHz to 11.45 GHz with the notching capability at WiMAX, C‐band, WLAN and downlink of X‐band for satellite communication. The gain of the antenna is improved by using two antennas in the stacked configuration without raising the overall size of the antenna in horizontal plane and maintaining the impedance matching over the ultrawideband range. The prototype of the proposed antenna has been fabricated on FR4 substrate and its performance parameters are measured and compared with the simulated results, which are in good agreement. The simulated and measured result shows the improvement of antenna peak gain by 4.2 dBi and thus improving the peak gain by 162%. The proposed antenna is an excellent candidate for the high gain UWB portable communication devices in the environment having different narrow interfering bands of WiMAX, C‐band, WLAN, and downlink X‐band of satellite communication. [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, a slot loaded ultra wideband monopole patch antenna with triple band-notched characteristic has been presented. The antenna consists of rectangular patch with three modified inverted U-shaped slots to create three notches at Wi-MAX (3.3-3.6 GHz), C-band (3.7-4.2 GHz), and WLAN (5.15-5.85 GHz) frequencies. Lumped-element equivalent circuit model and current distribution curves have been used to explain the triple band-rejection characteristics of the designed antenna. The proposed triple notch structure has been fabricated and tested against simulated data. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:138-142, 2017 [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a metamaterial-based tri-band antenna for WiMAX (2.5/3.5/5.5 GHz) and WLAN (5.2/5.8 GHz) application. The antenna comprises of a metallic patch of area 22 mm × 14 mm on the top of a substrate. The patch is etched with a T-shaped slot and meandered lines. At the bottom of substrate we have a partial, rectangular shaped ground plane along with an electric-inductive-capacitive resonator. The proposed antenna gives a desired impedance bandwidth along with an omnidirectional radiation pattern. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:558-561, 2016 [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents quad-directional magneto-dielectric (MD) resonator antenna configuration, designed using two different MD materials with stack configuration. These materials have been designed such that their temperature coefficient is approximately zero. The microwave dielectric constant (εr) and permeability (μr) of both materials are calculated by Nicholson-Ross-Weir conversion technique and found to be 8.02, 1.64 and 10.47, 1.52, respectively. The designed antenna can radiates in four directions simultaneously at the resonant frequency of 5.84 GHz. The beam shaping has been achieved using single feed and this property can be utilized for the angle diversity. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:62-64, 2016 [ABSTRACT FROM AUTHOR]

Primary (AL) amyloidosis results from the pathologic deposition of monoclonal light chains as amyloid fibrils. Studies of recombinant-derived variable region (VL) fragments of these proteins have shown an inverse relationship between thermodynamic stability and fibrillogenic potential. Further, ionic interactions within the VL domain were predicted to influence the kinetics of light chain fibrillogenicity, as evidenced from our analyses of a relatively stable Vλ6 protein (Jto) with a long range electrostatic interaction between Asp and Arg side chains at position 29 and 68, respectively, and an unstable, highly fibrillogenic Vλ6 protein (Wil) that had neutral amino acids at these locations. To test this hypothesis, we have generated two Jto-related mutants designed to disrupt the interaction between Asp 29 and Arg 68 (JtoD29A and JtoR68S). Although the thermodynamic stabilities of unfolding for these two molecules were identical, they exhibited very different kinetics of fibril formation: the rate of JtoD29A fibrillogenesis was slow and comparable to the parent molecule, whereas that of JtoR68S was significantly faster. High-resolution X-ray diffraction analyses of crystals prepared from the two mutants having the same space group and unit cell dimensions revealed no significant main-chain conformational changes. However, several notable side-chain alterations were observed in JtoR68S, as compared with JtoD29A, that resulted in the solvent exposure of a greater hydrophobic surface and modifications in the electrostatic potential surface. We posit that these differences contributed to the enhanced fibrillogenic potential of the Arg 68 mutant, since both Jto mutants lacked the intrachain ionic interaction and were equivalently unstable. The information gleaned from our studies has provided insight into structural parameters that in addition to overall thermodynamic stability, contribute to the fibril forming propensity of immunoglobulin light chains. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Allied species of crop Brassicas have potential value as donors of useful nuclear/organelle genomes. Eruca sativa, a member of subtribe Brassicineae, is resistant to white rust and well adapted to drought. Attempts to hybridize it with Brassica campestris by conventional methods were unsuccessful. However, hybrids were obtained by embryo rescue and the hybrid embryos were found to produce numerous secondary embryos in upto 7 to 8 subcultures. Plantlets developed from them exhibited morphological characteristics of both parents. The chromosome number of 2n = 42 showed that they were amphidiploids. The plants were allotetraploids (2n = 42) and showed 21 bivalents at M1 of meiosis. Hybridization of total DNA of the hybrids with two probes, a B. campestris tandem repeat DNA and 18s ribosomal DNA of wheat showed that it was derived from the genome of both parents. The hybrids are self-fertile and show the same high fertility even in A3 generation. They were selfed or crossed with B. juncea, B. campestris and B. nigra to screen for useful agronomical traits. Six more embryos of E. sativa x B. campestris have been obtained and their growth is being studied. Preliminary small scale field trials indicate that the selfed hybrid is comparable in yield with a high yielding commercial variety of B. juncea. [ABSTRACT FROM AUTHOR]

The characteristics of a bow-shaped microstrip patch antenna are analyzed and compared with a conventional rectangular microstrip antenna. The various parameters such as return loss, gain, and VSWR are determined and compared. It is found that the center frequency of the bow-shaped antenna is lower by about 12.82% than that of the conventional rectangular microstrip antenna. This implies that the size of the patch needs to be reduced in order to maintain the same resonant frequency. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 158–160, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11314 [ABSTRACT FROM AUTHOR]

The gene encoding biotin acetyl-CoA carboxylase ligase (BirA) from Mycobacterium tuberculosis was cloned and expressed in Escherichia coli with a C-terminal Strep-tag. PEG 4000 as well as PEG 8000 were used as precipitants at pH 7.5 to crystallize the protein using the vapour-diffusion technique. X-ray characterization of crystals at room temperature indicated that the crystals belonged to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 79.7, b = 62.8, c = 105.8 A. Assuming the presence of two BirA molecules in the asymmetric unit, the solvent content of the crystals was 44% (V(M) = 2.2 A(3) Da(-1)). When transferred to a cryoprotectant, crystals grown in the same drop exhibited a difference in one unit-cell parameter, with a = 60.1, b = 64.0, c = 103.6 A, but belonged to the same P2(1)2(1)2(1) space group. These crystals, with two molecules of BirA present per asymmetric unit, appeared to have a very low solvent content of 28% (V(M) = 1.7 A(3) Da(-1)).

Bacterioferritins (Bfrs) comprise a subfamily of the ferritin superfamily of proteins that play an important role in bacterial iron storage and homeostasis. Bacterioferritins differ from ferritins in that they have additional noncovalently bound haem groups. To assess the physiological role of this subfamily of ferritins, a greater understanding of the structural details of bacterioferritins from various sources is required. The gene encoding bacterioferritin A (BfrA) from Mycobacterium tuberculosis was cloned and expressed in Escherichia coli. The recombinant protein product was purified by affinity chromatography on a Strep-Tactin column and crystallized with sodium chloride as a precipitant at pH 8.0 using the vapour-diffusion technique. The crystals diffracted to 2.1 A resolution and belonged to space group P4(2), with unit-cell parameters a = 123.0, b = 123.0, c = 174.6 A.