Frequency-diverse multimode millimetre-wave constant-ϵr lens-loaded cavity.

This paper presents a physical frequency-diverse multimode lens-loaded cavity, designed and used for the purpose of the direction of arrival (DoA) estimation in millimetre-wave frequency bands for 5G and beyond. The multi-mode mechanism is realized using an electrically-large cavity, generating spatio-temporally incoherent radiation masks leveraging the frequency-diversity principle. It has been shown for the first time that by placing a spherical constant dielectric lens (constant-ϵr) in front of the radiating aperture of the cavity, the spatial incoherence of the radiation modes can be enhanced. The lens-loaded cavity requires only a single lens and output port, making the hardware development much simpler and cost-effective compared to conventional DoA estimators where multiple antennas and receivers are classically required. Using the lens-loaded architecture, an increase of up to 6 dB is achieved in the peak gain of the synthesized quasi-random sampling bases from the frequency-diverse cavity. Despite the fact that the practical frequency-diverse cavity uses a limited subset of quasi-orthogonal modes below the upper bound limit of the number of theoretical modes, it is shown that the proposed lens-loaded cavity is capable of accurate DoA estimation. This is achieved thanks to the sufficient orthogonality of the leveraged modes and to the presence of the spherical constant-ϵr lens which increases the signal-to-noise ratio (SNR) of the received signal. Experimental results are shown to verify the proposed approach.

Heritability, genetic and phenotypic correlations of egg quality traits in Iranian native fowl.

1. The objective was to estimate heritability, genetic and phenotypic correlations for egg quality traits of Iranian native fowl at the Yazd Breeding Centre. 2. External and internal egg quality traits were measured on 1200 eggs from 794 hens of the 6th generation. A multivariate animal model with restricted maximum likelihood procedure was applied to estimate heritability, genetic and phenotypic correlations for egg quality traits using ASREML. 3. Heritability estimates for external egg quality traits ranged from 0·18 to 0·57 and for internal egg quality traits from 0·24 to 0·60. 4. For external egg quality traits, genetic correlation between egg weight and eggshell thickness (EST) was positive (0·36) and EST showed high genetic correlations with eggshell weight (0·84) and eggshell strength (0·55). This implies that heavier eggs tend to have thicker and stronger shells. 5. For internal egg quality traits, albumen height showed high positive genetic correlations with albumen weight (0·52), albumen index (0·98), yolk height (0·72) and yolk index (0·57). 6. Our results show that it is feasible to improve egg quality in Iranian fowl through selection for albumen height.

Different models for evaluation of growth traits and Kleiber ratio in an experimental flock of Iranian fat-tailed Afshari sheep.

Records for Afshari sheep were retrieved from data collected between 2000 and 2005 at the Zanjan University experimental flock, at Zanjan, Iran. (Co)variance components and corresponding genetic parameters for birth weight (BW), weaning weight (WW), 6-month weight (W6), average daily gain from birth to weaning (ADGa), from birth to 6 months (ADGb), from weaning to 6 months (ADGc), Kleiber ratio at weaning (WWKR) and Kleiber ratio at 6 months of age (W6KR) were estimated using univariate and bivariate analyses by the DFREML procedure. The Kleiber ratio, defined as growth rate/metabolic weight, has been suggested to be a useful indicator of growth efficiency and an indirect selection criterion for feed conversion. Estimates of direct heritability (h(2)) were 0.23, 0.27, 0.11, 0.22, 0.07, 0.01, 0.13 and 0.06 for BW, WW, W6, ADGa, ADGb, ADGc, WWKR and W6KR, respectively. Maternal genetic effects represented a relatively large proportion of the total phenotypic variance for BW (m(2) = 0.22), whereas maternal permanent environmental effects were significant for W6 (c(2) = 0.15), ADGb (c(2) = 0.16), ADGc (c(2) = 0.14) and W6KR (c(2) = 0.16). Results of bivariate analyses indicated the variable genetic correlations between traits. The largest positive genetic relationships were between adjacent measurements. The moderate estimates of h(2) for early growth traits indicate that in Afshari sheep faster genetic improvement through selection is possible for these traits. In order to increase the efficiency of feed conversion, use of Kleiber ratio in selection programmes was recommended.

An investigation of the kinetic and anti-angiogenic properties of plant glycoside inhibitors of thymidine phosphorylase.

We investigated the potential of symplocomoside (1) and symponoside (2), glycosides isolated from the bark of Symplocos racemosa to inhibit thymidine phosphorylase (TP) activity and associated angiogenesis. Compound 1 was a reversible, noncompetitive inhibitor of deoxythymidine binding to TP (IC(50) = 65.45 +/- 5.08 microM; K(i) = 62.83 +/- 2.10 microM) and 2 was a reversible, uncompetitive inhibitor (IC(50) = 94.17 +/- 4.05 microM; K(i) = 101.95 +/- 1.65 microM). Molecular modeling analysis indicated that both compounds bound at the active site of the enzyme but not solely to amino acid residues involved in catalysis. Both compounds were active in in vitro angiogenic assays inhibiting endothelial cell migration and invasion in Matrigel, but did not inhibit growth factor-induced proliferation and were not cytotoxic. Compound 1 may have potential as an anti-angiogenic and anti-tumor agent.

Kinetics studies on the lignan class of natural compounds that inhibits alpha-chymotrypsin.

The mechanism of inhibition of the alpha-chymotrypsin enzyme by two lignans of the fused bistetrahydrofuran series, epiexcelsin (1) and 5'-demethoxyepiexcelsin (2), which were isolated from the Commiphora mukul Engl., was investigated. Lineweaver-Burk and Dixon plots and their secondary replots showed that these compounds were noncompetitive inhibitors of the enzyme. K(i) values for 1 and 2 were found to be 22.29 +/- 0.015 and 336.30 +/- 0.053 microM, respectively.

New salirepin derivatives from Symplocos racemosa.

The phytochemical investigation of the n-butanol soluble fraction of the bark of stem of Symplocos racemosa Roxb. yielded two new phenolic glycosides of salirepin series, symplocuronic acid (1) and sympocemoside (2), while salirepin (3) was isolated for the first time from this plant. The structures of the new compounds were identified by 1D and 2D NMR techniques along with other spectral evidences and by comparison with the published data of closely related compounds.