[en] The effect of substitution of Mg–Zr for Fe in M-type barium hexaferrite (BHF) and of processing technique on the magnetic properties and microstructure has been reported in the present paper. Significant changes in magnetic properties have been observed on substituting Fe ions by Mg and Zr ions in M-type barium hexaferrite, i.e. BaFe₁₂O₁₉ as well as by single mode microwave processing. The single mode microwave processing of the undoped sample reduced the coercivity to nearly 25% of the value for the sintered sample along with the enhancement in magnetization, thereby making it suitable for memory devices. The improvement in magnetic properties is explained on the basis of microstructure. The addition of substituents, though assisted in the formation of single phase, it, however, degraded the magnetization besides decreasing the coercivity, possibly due to substitution at the octahedral sites

[en] Purpose: To investigate dose deformation-invariance in adaptive prostate radiation treatment. Methods: A 19 patient prostate cancer-cohort with 8–13 CTs/patient is used. The 79.2 Gy plans are developed on the reference image using seven 6 and 18 MV intensity-modulated beams with identical RTOG 0126 objectives. Dose on the subsequent images is evaluated in two ways: (A1) Dose is recalculated on each image. (A2) The initially planned dose distribution is copied to each image. A2 assumes dose-invariance in the accelerator-coordinate-system. Effects of patient miss-alignment are simulated by 27 per-patient image shifts; 0 and ±10 mm in left–right, anterior–posterior and superior–inferior directions. The per-voxel dose differences for each patient image, total accumulated patient dose, and dose–volume metrics (CTV-D98 and -D90, bladder- and rectum-D50, -D35, -D25 and -D15) are used to compare A1 and A2. Results: The per-voxel mean percent difference in A1 and A2 dose over all patient images at 6 MV is (0.01 ± 1.56)% and at 18 MV is (0.00 ± 0.96)%. For 6 MV and 18 MV plans, the root-mean-square-percentage-error (RMSPE) in A2 over all patient image shifts are CTV-D98 = 0.94 and 0.55, CTV-D90 = 0.92 and 0.55, rectum-D50, -D35, -D25 and -D15 = 1.00, 0.96, 0.86, 0.80 and 0.84, 0.96, 0.92, 1.05; and bladder-D50, -D35, -D25, -D15 = 1.07, 0.88, 0.78, 0.72 and 1.61, 0.93, 0.67, 0.51. The dose differences are not correlated to the dice-similarity coefficients; with respective correlation-coefficients for CTV, rectum and bladder being −0.17, −0.17 and 0.081. Conclusions: Assumption of shift- and deformation-invariant dose distributions on an average introduces <2% error in evaluated dose–volume metrics for 6 and 18 MV IMRT prostate plans. Use of invariant dose distributions has a potential to reduce online re-planning time and permit pre-planning based on tissue deformation models.

[en] The probabilities [η_Lij (R)] for transfer of vacancies to the M- and N-shells following radiative decay of Li (i = 1,2,3 ) sub-shell vacancies for elements with 77 ≤ Z ≤ 83 have been deduced using theoretical photoionization cross sections and the measured fluorescence cross sections for the L_i sub-shell x-rays following ionization by the 59.54 keV γ-rays (B_L1 < E_inc < B_K )and for the L3 sub-shell x-rays following ionization by the K x-rays of a suitable secondary target (B_L3 < E_Kα < B_L1/L2 < E_Kβ< B_K); where B_K/Li probabilities [η_Lij (R) (i = 1 and J = M, N)] are found to be higher by 15-30% than those calculated using the theoretical Dirac-Fock model based radiative transition rates and relativistic Dirac-Hartree-Slater model based non-radiative transition probabilities. The [η_Lij (R)] (i = 2, 3 and J = M, N) exhibit good agreement with the calculated ones

[en] Full text: The L₁-L₃ Coster-Kronig (CK) yield, f₁₃ for the elements ₇₀Yb, ₇₁Lu, ₇₄ W, ₇₅Re, ₇₉Au, ₈₀Hg, and ₈₁Tl, elements were determined using the measured production cross sections for La X-rays emitted following selective ionization among the L_i (i = 1,2,3) sub-shells by the Ge/Se/Rb K X-rays and the 59.54 keV γ-rays. The photon sources consisting of an ²⁴¹Am source in (i) the direct excitation mode and (ii) the secondary excitation mode together with the Ge/Se/RbCl secondary exciter. The X-ray spectra from targets were taken using a Si(Li) detector. The present measured f₁₃ yield values are found to be substantially lower

[en] The L₁-L₃ Coster-Kronig (CK) yield f₁₃ for the ₇₀Yb, ₇₁Lu, ₇₄W, ₇₅Re, ₇₉Au, ₈₀Hg, and ₈₁Tl elements was deduced using measured intensities of the Lα x rays emitted following decay of the L_i-subshell (i=1,2,3) vacancies produced in widely different proportions by the 59.54 keV γ rays (B_L1< E_inc< B_K) and the Ge/Se/Rb K x rays (B_L3< E_Kα< B_L2,B_L1L2< E_Kβ< B_K); where B_KLi is the K-shell/L_i-subshell binding energy of the target element. An energy-dispersive x-ray fluorescence set up, involving photon sources consisting of a ²⁴¹Am annular source in the direct and secondary excitation modes along with the Ge/Se/RbCl secondary exciter and a Si(Li) detector, was used for the measurements. The measured f₁₃ yields for ₇₀Yb, ₇₁Lu, and ₇₄W are found to agree with the values based on the relativistic Dirac-Hartree-Slater (RDHS) calculations, while those for ₇₉Au, ₈₀Hg, and ₈₁Tl are lower by ∼20%. The measured f₁₃ yields exhibit a jump from 0.354(24) for ₇₄W to 0.450(27) for ₇₅Re compared to that from 0.352 to 0.640 as predicted by the RDHS calculations due to onset of the intense L₁-L₃M₅ CK transition

[en] Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight disease that limits the rice production globally. The bacterium secretes effector proteins directly into plant cells through a type III secretion system (T3SS). Here, we examined the role of a conserved XopR T3SS-effector in the suppression of host basal defense response. Phylogenetic and sequence analysis showed that XopR is well conserved within Xoo strains but shares varying degree of similarity among the other Xanthomonas species. The expression of XopR was shown to be regulated by hrpX, a key regulator of hrp cluster. For functional analysis we employed two mutant strains of Xoo, one lacks xopR gene and other lacks hrpX gene (making the strain defective in T3SS). Programmed cell death (PCD) events was examined both in rice and tobacco leaves through trypan blue staining method. In XopR expressing tobacco leaves the PCD induction was compromised. We observed higher PCD on rice leaves inoculated with Xoo mutants lacking either xopR or functional T3SS as compared to wild type. Contrary, when xopR gene was complemented in mutated strain the PCD was suppressed which clearly suggests that XopR acts as suppressor of the PCD mediated defense response. The EYFP::XopR fusion protein was shown to be localized to the plasma membrane of Nicotiana benthamiana and onion epidermal cells. Altogether our study leads to the understanding that XopR T3SS-effector is essential for Xoo to suppress PCD, primarily to support the in planta colonization of Xoo during blight pathogenesis.

[en] The ₅₅Cs nuclei lie in the transitional region between the primarily spherical ₅₀Sn and the well-deformed ₅₇La and ₅₈Ce nuclei. High spin states in doubly-odd ¹²²Cs nuclei were studied

[en] Curie temperature of polycrystalline barium hexaferrite (BaFe₁₂O₁₉), prepared by conventional solid state technique, is anomalously and significantly enhanced (by nearly 15%) by energetic heavy ion irradiation (150 MeV, Ag¹²⁺) at ambient temperature due to dense electronic excitations Moderate fluence (1 × 10¹² ions/cm²) induces structural defects giving rise to above enhancement. As established by X-ray diffraction, scanning electron microscopy and Raman studies, higher fluence (1 × 10¹³ ions/cm²) has structurally transformed the sample to amorphous phase with marginal change in magnetization and Curie temperature

[en] The ₅₅Cs and ₅₆Ba nuclei lie in the transitional region between the primarily spherical ₅₀Sn and the well-deformed ₅₇La and ₅₈Ce nuclei. These nuclei are of particular interest as they are expected to inherit the features of both the regions and hence, reflect rich nuclear structure. Experiment were carried to study high spin states in doubly-odd ¹²²Cs and even-even ¹²²Ba nuclei

[en] An EDXRF set-up has been used to generate mechanistic information on the photolytic and physicochemical events leading to deposition of free elements from various diorganyl ditellurides in different solvents and in a microemulsion system. The method is characterized by the use of 59.54 keV γ-rays as a monoenergetic radiation source and the decomposition process is studied through the change in count rate of the characteristic K _α X-ray peak of tellurium in different ditelluride solutions. In the experimental work different aspects have been examined to optimize the sensitivity of the method. It has been found that in coordinating solvents, the rate of decay of dibenzyl ditelluride is much faster in comparison to diphenyl and dipyridyl ditellurides. Moreover, in dibenzyl ditelluride the decay is accompanied with the complete precipitation of elemental tellurium, whereas an adduct is formed by coordination of the solvent molecule with diphenyl/dipyridyl ditelluride. It has also been observed that the methyl substitution in organyl rings makes the ditellurides more stable while the microemulsion system exhibits faster decomposition