Inequalities for eigenvalues of a system of higher-order differential equations

We establish some sharper inequalities for eigenvalues of a system of higher-order differential equations. Moreover, we present some sharper estimates for the upper bound of the (k +1)th eigenvalue and the gaps of its consecutive eigenvalues.Встановлено дєякі 6ільш точні оцінки для власних значень системи диференціальних рівнянь вищого порядку. Ми також наводимо деякі більш точні оцінки для оцінки зверху (k +1)-го власного значення i щілин між будь-якими двома послідовними власними значеннями

Reply to "Comment on `First-principles calculation of the superconducting transition in MgB2 within the anisotropic Eliashberg formalism'"

The recent preprint by Mazin et al. [cond-mat/0212417] contains many inappropriate evaluations and/or criticisms on our published work [Phys. Rev. B 66, 020513 (2002) and Nature 418, 758 (2002)]. The preprint [cond-mat/0212417v1] was submitted to Physical Review B as a comment on one of our papers [Phys. Rev. B 66, 020513 (2002)]. In the reviewing process, Mazin et al. have withdrawn many of the statements contained in cond-mat/0212417v1, however two claims remain in their revised manuscript [cond-mat/0212417v3]: (1) the calculated variations of the superconducting energy gap within the sigma- or the pi-bands are not observable in real samples due to scatterings, and (2) the Coulomb repulsion mu(k,k') is negligibly small between sigma- and pi-states and thus should be approximated by a diagonal 2 x 2 matrix in the sigma and pi channels. Here, we point out that the former does not affect the validity of our theoretical work which is for the clean limit, and that the latter is not correct

3D Spatially hybrid model for streamer discharge

Streamers are rapidly growing plasma filaments. They play an important role in the early stages of lightning and, as well as in industrial application such as lighting, plasma assisted combustion and disinfection. In previous work, the first generation of 3D spatially hybrid codes was developed by Chao Li, to study the propagation of negative streamer without photoionization in a background field above the break-down value[1-2]. We now have set up the second generation codes to improve and optimize the original program, and to make it accessible. Adaptive Mesh Refinement and parallel computing technique are being adopted as well, to increase the accuracy, efficiency and parameter range of simulations. The codes are being used to study the streamers emergence from the inception cloud, streamers branching and feather formation in different N2:O2 ratios, and streamers interaction. [1]C. Li et al., J. Comput. Phys. 231, 1020 (2012); [2]C. Li et al., Plasma Sources Sci. Technol.(submitted), preprint: http://arxiv.org/abs/1203.503

Towards user-friendly, public domain simulations of the precursor of lightning: streamers

Streamers play an important role in the early stages of lightning and can be directly seen as sprite discharges. Many kinds of streamer discharge models developed at CWI are presented, using Particle-in-cell/Monte Carlo, fluid and hybrid codes from 1D to 3D. The codes are being improved and documented currently, to make them user-friendly and available on internet for potential users

Cloning and characterisation of a maize carotenoid cleavage dioxygenase (ZmCCD1) and its involvement in the biosynthesis of apocarotenoids with various roles in mutualistic and parasitic interactions

Colonisation of maize roots by arbuscular mycorrhizal (AM) fungi leads to the accumulation of apocarotenoids (cyclohexenone and mycorradicin derivatives). Other root apocarotenoids (strigolactones) are involved in signalling during early steps of the AM symbiosis but also in stimulation of germination of parasitic plant seeds. Both apocarotenoid classes are predicted to originate from cleavage of a carotenoid substrate by a carotenoid cleavage dioxygenase (CCD), but the precursors and cleavage enzymes are unknown. A Zea mays CCD (ZmCCD1) was cloned by RT-PCR and characterised by expression in carotenoid accumulating E. coli strains and analysis of cleavage products using GC¿MS. ZmCCD1 efficiently cleaves carotenoids at the 9, 10 position and displays 78% amino acid identity to Arabidopsis thaliana CCD1 having similar properties. ZmCCD1 transcript levels were shown to be elevated upon root colonisation by AM fungi. Mycorrhization led to a decrease in seed germination of the parasitic plant Striga hermonthica as examined in a bioassay. ZmCCD1 is proposed to be involved in cyclohexenone and mycorradicin formation in mycorrhizal maize roots but not in strigolactone formatio

Characterization of an INVS Model IV Neutron Counter for High Precision (γ,n\gamma,n) Cross-Section Measurements

A neutron counter designed for assay of radioactive materials has been adapted for beam experiments at TUNL. The cylindrical geometry and 60% maximum efficiency make it well suited for ($\gamma,n$) cross-section measurements near the neutron emission threshold. A high precision characterization of the counter has been made using neutrons from several sources. Using a combination of measurements and simulations, the absolute detection efficiency of the neutron counter was determined to an accuracy of $\pm$ 3% in the neutron energy range between 0.1 and 1 MeV. It is shown that this efficiency characterization is generally valid for a wide range of targets.Comment: 22 pages, 13 figure

Altered renal hemodynamics and impaired myogenic responses in the fawn-hooded rat

The present study examined whether an abnormality in the myogenic response of renal arterioles that impairs autoregulation of renal blood flow (RBF) and glomerular capillary pressure (PGC) contributes to the development of renal damage in fawn-hooded hypertensive (FHH) rats. Autoregulation of whole kidney, cortical, and medullary blood flow and PGC were compared in young (12 wk old) FHH and fawn-hooded low blood pressure (FHL) rats in volume-replete and volume-expanded conditions. Baseline RBF, cortical and medullary blood flow, and PGC were significantly greater in FHH than in FHL rats. Autoregulation of renal and cortical blood flow was significantly impaired in FHH rats compared with results obtained in FHL rats. Myogenically mediated autoregulation of PGC was significantly greater in FHL than in FHH rats. PGC rose from 46 +/- 1 to 71 +/- 2 mmHg in response to an increase in renal perfusion pressure from 100 to 150 mmHg in FHH rats, whereas it only increased from 39 +/- 2 to 53 +/- 1 mmHg in FHL rats. Isolated perfused renal interlobular arteries from FHL rats constricted by 10% in response to elevations in transmural pressure from 70 to 120 mmHg. In contrast, the diameter of vessels from FHH rats increased by 15%. These results indicate that the myogenic response of small renal arteries is altered in FHH rats, and this contributes to an impaired autoregulation of renal blood flow and elevations in PGC in this strain

Influence of electrode distance on heating behaviour associated to radio frequency processing of low moisture foods

Temperature uniformity and heating rate subjected to radio frequency (RF) heating have major impact on the quality of treated low moisture foods. The objective of this paper was to analyse the influence of electrode distance on the heating behaviour of RF on condition that the sample shape, size, and location between the electrodes were defined. Considering peanut butter (PB) and wheat flour (WF) as sample food, a 3D computer simulation model was developed using COMSOL, which was experimentally validated by a RF machine (27.12 MHz, 6 kW). Specifically, the electrode distances were selected as 84, 89, 93, 99 and 89, 93, 98, 103 (mm) for RF heating of PB and WF, respectively. Results showed that the simulated results and experimental data agreed well; the temperature-time histories of the RF heating of PB and WF were approximate straight lines; both the temperature uniformity index and the heating rate decreased with the increase of the electrode distance; the heating rate had a negative logarithmic linear relationship with the electrode distance, which was independent of the types, geometry shapes and sizes of low moisture foods