A highly scalable dielectric metamaterial with superior capacitor performance over a broad temperature.

Although many polymers exhibit excellent dielectric performance including high energy density with high efficiency at room temperature, their electric and dielectric performance deteriorates at high temperatures (~150°C). Here, we show that nanofillers at very low volume content in a high-temperature (high-glass transition temperature) semicrystalline dipolar polymer, poly(arylene ether urea), can generate local structural changes, leading to a marked increase in both dielectric constant and breakdown field, and substantially reduce conduction losses at high electric fields and over a broad temperature range. Consequently, the polymer with a low nanofiller loading (0.2 volume %) generates a high discharged energy density of ca. 5 J/cm3 with high efficiency at 150°C. The experimental data reveal microstructure changes in the nanocomposites, which, at 0.2 volume % nanofiller loading, reduce constraints on dipole motions locally in the glassy state of the polymer, reduce the mean free path for the mobile charges, and enhance the deep trap level.

Enhancement of the dielectric response in polymer nanocomposites with low dielectric constant fillers.

In order to increase the dielectric constants of polymer-based dielectrics, composite approaches, in which inorganic fillers with much higher dielectric constants are added to the polar polymer matrix, have been investigated. However, high dielectric constant fillers cause high local electric fields in the polymer, resulting in a large reduction of the electric breakdown strength. We show that a significant increase in the dielectric constant can be achieved in polyetherimide nanocomposites with nanofillers whose dielectric constant can be similar to that of the matrix. The presence of nanofillers reduces the constraints on the dipole response to the applied electric field, thus enhancing the dielectric constant. Our results demonstrate that through nanostructure engineering, the dielectric constant of nanocomposites can be enhanced markedly without using high dielectric constant nanofillers.

Identification of polymorphism in exons 7 and 12 of lactoferrin gene and its association with incidence of clinical mastitis in Murrah buffalo.

Lactoferrin gene is one of the important candidate genes for mastitis resistance. The gene is located on chromosome BTA 22 and consists of 17 exons spanning over 34.5 kb of genomic DNA. The present study was undertaken with the objectives to identify allelic variants in exons 7 and 12 of lactoferrin gene and to analyze association between its genetic variants and incidence of clinical mastitis in Murrah buffalo. The amplification of exons 7 and 12 of lactoferrin gene yielded amplicons of 232- and 461-bp sizes. PCR-restriction fragment length polymorphism (RFLP) analysis of 232-bp amplicon using BccI restriction enzyme revealed three genotypes (AA, AB, and BB) with frequencies of 0.62, 0.22, and 0.16, respectively. The frequencies of two alleles, A and B, were estimated as 0.73 and 0.27. Hpy188I-RFLP for 461-bp amplicon revealed polymorphism with three genotypes, CC, CD, and DD, with respective frequencies of 0.06, 0.39, and 0.56, whereas frequencies for C and D alleles were 0.25 and 0.75. The chi-square (χ(2)) analysis revealed a significant association between incidence of clinical mastitis and genetic variants of exon 7, and animals of AA genotype of exon 7 were found to be least susceptible to mastitis. The findings indicate potential scope for incorporation of lactoferrin gene in selection and breeding of Murrah buffaloes for improved genetic resistance to mastitis.

Principal component analysis of biometric traits to reveal body confirmation in local hill cattle of Himalayan state of Himachal Pradesh, India.

AIM: In the present study, biometric traits (body length [BL], heart girth [HG], paunch girth (PG), forelimb length (FLL), hind limb length (HLL), face length, forehead width, forehead length, height at hump, hump length (HL), hook to hook distance, pin to pin distance, tail length (TL), TL up to switch, horn length, horn circumference, and ear length were studied in 218 adult hill cattle of Himachal Pradesh for phenotypic characterization. MATERIALS AND METHODS: Morphological and biometrical observations were recorded on 218 hill cattle randomly selected from different districts within the breeding tract. Multivariate statistics and principal component analysis are used to account for the maximum portion of variation present in the original set of variables with a minimum number of composite variables through Statistical software, SAS 9.2. RESULT: Five components were extracted which accounted for 65.9% of variance. The first component explained general body confirmation and explained 34.7% variation. It was represented by significant loading for BL, HG, PG, FLL, and HLL. Communality estimate ranged from 0.41 (HL) to 0.88 (TL). Second, third, fourth, and fifth component had a high loading for tail characteristics, horn characteristics, facial biometrics, and rear body, respectively. CONCLUSION: The result of component analysis of biometric traits suggested that indigenous hill cattle of Himachal Pradesh are small and compact size cattle with a medium hump, horizontally placed short ears, and a long tail. The study also revealed that factors extracted from the present investigation could be used in breeding programs with sufficient reduction in the number of biometric traits to be recorded to explain the body confirmation.