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 have withdrawn many of the statements contained in cond-mat/0212417v1, however two claims remain in their revised manuscript [cond-mat/0212417v3]: (1) the calculated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

Modification Of Aggregate Grading For Porous Asphalt.

In the 1970’s, the fatality index on Malaysian roads exceeded 20. In 1991, a Cabinet Committee on Road Safety was set up to come up with measures to reduce the predicted number of deaths by 30% or translated into a fatality index of 3.14 by the turn of the century. Among the measures suggested included the application of porous asphalt

A highly active and redox stable novel ceramic anode with in-situ exsolution of nanocatalysts

Layered perovskite novel ceramic anode (referred to as SGNM) phases were evaluated for use in solid oxide fuel cells (SOFCs). Hydrogen temperature programmed reduction (H2-TPR) analysis of the SGNM materials revealed that significant exsolution of Ni nanoparticles occurred. Consistently, the SGNM on the LSGM electrolyte showed low electrode polarization resistance in H2 at 800 °C. Moreover, after 10 redox cycles at 750 °C, the electrode area specific resistance of the SGNM anode in H2 slightly increased during cycle, indicating excellent redox stability in both reducing and oxidizing atmospheres. An LSGM-electrolyte supported SOFC employing an SGNM-based anode yielded a high power density of ~1 W cm-2 at 800 °C, which is the best performance among the any SOFCs with Ruddlesden-Popper based ceramic anodes to date. After performance measurement, we observed that metallic Ni nanoparticles (~ 25 nm) were grown in situ and homogeneously distributed on the SGNM anode surface. These exsolved nanocatalysts are believed to significantly enhance the hydrogen oxidation activity of the SGNM material. These results demonstrate that the novel SGNM material is promising as a high catalytically active and redox-stable anode for SOFCs.. Please click Additional Files below to see the full abstract

PI3-kinase mutation linked to insulin and growth factor resistance in vivo

The phosphatidylinositol 3-kinase (PI3K) signaling pathway is central to the action of insulin and many growth factors. Heterozygous mutations in the gene encoding the p85alpha regulatory subunit of PI3K (PIK3R1) have been identified in patients with SHORT syndrome - a disorder characterized by short stature, partial lipodystrophy, and insulin resistance. Here, we evaluated whether SHORT syndrome-associated PIK3R1 mutations account for the pathophysiology that underlies the abnormalities by generating knockin mice that are heterozygous for the Pik3r1Arg649Trp mutation, which is homologous to the mutation found in the majority of affected individuals. Similar to the patients, mutant mice exhibited a reduction in body weight and length, partial lipodystrophy, and systemic insulin resistance. These derangements were associated with a reduced capacity of insulin and other growth factors to activate PI3K in liver, muscle, and fat; marked insulin resistance in liver and fat of mutation-harboring animals; and insulin resistance in vitro in cells derived from these mice. In addition, mutant mice displayed defective insulin secretion and GLP-1 action on islets in vivo and in vitro. These data demonstrate the ability of this heterozygous mutation to alter PI3K activity in vivo and the central role of PI3K in insulin/growth factor action, adipocyte function, and glucose metabolism

Systems analysis reveals a transcriptional reversal of the mesenchymal phenotype induced by SNAIL-inhibitor GN-25

Abstract Background HMLEs (HMLE-SNAIL and Kras-HMLE, Kras-HMLE-SNAIL pairs) serve as excellent model system to interrogate the effect of SNAIL targeted agents that reverse epithelial-to-mesenchymal transition (EMT). We had earlier developed a SNAIL-p53 interaction inhibitor (GN-25) that was shown to suppress SNAIL function. In this report, using systems biology and pathway network analysis, we show that GN-25 could cause reversal of EMT leading to mesenchymal-to-epithelial transition (MET) in a well-recognized HMLE-SNAIL and Kras-HMLE-SNAIL models. Results GN-25 induced MET was found to be consistent with growth inhibition, suppression of spheroid forming capacity and induction of apoptosis. Pathway network analysis of mRNA expression using microarrays from GN-25 treated Kras-HMLE-SNAIL cells showed an orchestrated global re-organization of EMT network genes. The expression signatures were validated at the protein level (down-regulation of mesenchymal markers such as TWIST1 and TWIST2 that was concurrent with up-regulation of epithelial marker E-Cadherin), and RNAi studies validated SNAIL dependent mechanism of action of the drug. Most importantly, GN-25 modulated many major transcription factors (TFs) such as inhibition of oncogenic TFs Myc, TBX2, NR3C1 and led to enhancement in the expression of tumor suppressor TFs such as SMAD7, DD1T3, CEBPA, HOXA5, TFEB, IRF1, IRF7 and XBP1, resulting in MET as well as cell death. Conclusions Our systems and network investigations provide convincing pre-clinical evidence in support of the clinical application of GN-25 for the reversal of EMT and thereby reducing cancer cell aggressiveness

Phonon structure in I-V characteristic of MgB2_{2} point-contacts

The search of the phonon structure at the above-gap energies was carried out for $d^{2}V/dI^{2}(V)$ spectra of MgB$_{2}$ point contacts with a normal metal. The two-band model is assumed not only for the gap structure in $dV/dI(V)$-characteristics, but also for phonons in $d^{2}V/dI^{2}(V)$ point-contact spectra, with up to the maximum lattice vibration energy. Since the current is carried mostly by charges of 3D-band, whereas the strong electron-phonon interaction occurs in 2D-band, we observe the phonon peculiarities due to ''proximity'' effect in {\it k}-space, which depends on the variation of interband coupling through the elastic scattering.Comment: 6 pages, 4 figures, revtex4, reported in International Conference "Modern Problems in Superconductivity", 9-13 September, Yalta, Ukrain

Small anisotropy of the lower critical field and s±s_\pm-wave two-gap feature in single crystal LiFeAs

The in- and out-of-plane lower critical fields and magnetic penetration depths for LiFeAs were examined. The anisotropy ratio $\gamma_{H_{c1}}(0)$ is smaller than the expected theoretical value, and increased slightly with increasing temperature from 0.6$T_c$ to $T_c$. This small degree of anisotropy was numerically confirmed by considering electron correlation effect. The temperature dependence of the penetration depths followed a power law($\sim$$T^n$) below 0.3$T_c$, with $n$$>$3.5 for both $\lambda_{ab}$ and $\lambda_c$. Based on theoretical studies of iron-based superconductors, these results suggest that the superconductivity of LiFeAs can be represented by an extended $s_\pm$-wave due to weak impurity scattering effect. And the magnitudes of the two gaps were also evaluted by fitting the superfluid density for both the in- and out-of-plane to the two-gap model. The estimated values for the two gaps are consistent with the results of angle resolved photoemission spectroscopy and specific heat experiments.Comment: 10 pages, 5 figure