Dynamical mean-field theory of Hubbard-Holstein model at half-filling: Zero temperature metal-insulator and insulator-insulator transitions

We study the Hubbard-Holstein model, which includes both the electron-electron and electron-phonon interactions characterized by $U$ and $g$, respectively, employing the dynamical mean-field theory combined with Wilson's numerical renormalization group technique. A zero temperature phase diagram of metal-insulator and insulator-insulator transitions at half-filling is mapped out which exhibits the interplay between $U$ and $g$. As $U$ ($g$) is increased, a metal to Mott-Hubbard insulator (bipolaron insulator) transition occurs, and the two insulating states are distinct and can not be adiabatically connected. The nature of and transitions between the three states are discussed.Comment: 5 pages, 4 figures. Submitted to Physical Review Letter

Editorial introduction: Green Planning

This special issue deals with research presented at the biannual SPSD conference held in Seoul, South Korea in 2017. Specifically, about half of the presentations (total 68) were submitted in full length, aiming for official publication in IRSPSD and from these, this issue was initially based on nine papers. Five papers were finally accepted and comprise this special issue

Functional Characterization of Siberian Wild Rye Grass \u3cem\u3eEsHSP 16.9\u3c/em\u3e Gene Conferring Diverse Stress Tolerance in Prokaryotic Cells

Siberian wild rye (Elymus sibiricus L.) is a perennial, caespitose, and self-pollinating grass indigenous to Northern Asia and also is widely distributed from Northern Europe to Japan. The plant shows strong environmental adaptability with tolerance to drought and cold; thus, it is often used as forage resources (Yan et al., 2007). Environmental stresses caused by global warming are acknowledged to be as a serious issue in agriculture due to reductions of crop productivity (Ahuja et al., 2010). Genetic natural breeding of Siberian wild rye would potentially increase the productivity of forage crops; however, genetic studies on this grass have yet to be conducted. Heat shock proteins (Hsps) are the well characterized stress inducible proteins playing as molecular chaperones in prokaryotes and eukaryotes. We have also identified two differently localized small Hsps: rice chloroplastic and alfalfa mitochondrial Hsps confer tolerance to oxidative and heat stresses in tall fescue and to salinity and arsenic stresses in E. coli, tobacco, and tall fescue, respectively (Lee et al., 2012a; Lee et al., 2012b). Here, we cloned the small Hsp16.9 gene from various heat stress-induced fragments in Siberian wild rye using differentially expressed gene (DEG) analysis. We examined the mRNA expression of EsHsp16.9, in vitro molecular chaperone activity and in vivo stress tolerance by using a prokaryotic system against diverse environmental stresse

Tempcore Process Simulator to Analyze Microstructural Evolution of Quenched and Tempered Rebar

Featured Application Proposed process simulator can be widely applied to parameter design of industrial Tempcore process with reduced cost and time. Abstract Tempcore process simulator (TPS) has been developed in this study to analyze the microstructural evolution of quenched and tempered rebar. There has been an increasing need to relate the complex microstructures to the resulting properties of quenched and tempered rebar. However, information on such relationships typically requires precise thermal histories imposed on the workpiece. Therefore, TPS, capable of simulating the Tempcore process, has been developed to produce high-fidelity data. TPS mainly consists of a vacuum induction furnace, pilot rolling mill, box furnace, and cooling unit to simulate shop floor operations. A series of experimental tests were successfully carried out with various parameters, such as reheating temperature, water flow, water pressure, and cooling time. The effects of chemical compositions and cooling time on the microstructural evolution and mechanical properties of quenched and tempered rebar have been analyzed to validate the performance of TPS. The results show that TPS can simulate the Tempcore process with a high degree of fidelity and reliability.11Ysciescopu

Electric polarization enhancement in multiferroic CoCr2O4 crystals with Cr-site mixing

Single crystals of multiferroic cobalt chromite Co (Cr2-x Cox) O4 have been grown via several methods to have different Co3+ doping levels (x=0.0, 0.14, and 0.18). Under magnetic fields, all the crystals display electric polarization reversal below their spiral spin ordering temperatures. We find that both saturated electric polarization and magnetization under magnetic fields increase significantly with the increase in x. This result can be qualitatively explained by a broken balance between at least two electric polarization contributions existing in CoCr2 O4 and is expected to be useful in tailoring electric polarization in similar kinds of multiferroics. © 2009 American Institute of Physics.open222

Lumbopelvic Sagittal Alignment and Foraminal Height from Single Interbody Cage in L5-S1 Segment: Comparison between Anterior Cage for OLIF (Oblique Lumbar Interbody Fusion) and Curvilinear Cage for TLIF (Transforaminal Interbody Fusion)

Objective To evaluate a radiological difference between the oblique lumbar interbody fusion (OLIF) L5-S1 and transforaminal lumbar interbody fusion (TLIF) L5-S1 procedure. Methods 16 patients who underwent single-level OLIF L5-S1 and 32 patients of TLIF L5-S1 were retrospectively reviewed. Assessment of the lumbopelvic parameters and the height of disc space and L5-S1 neural foramen was performed before surgery as well as a month after surgery. Results Preoperatively, OLIF L5-S1 group and TLIF group showed similar lumbar lordosis (LL), segmental lordosis (SL), pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS); (p=0.08, 0.48, 0.67, 0.19 and 0.12, respectively). Postoperatively those parameters did not show statistically significant differences between two groups (p=0.17, 0.32, 0.53, 0.16 and 0.19, respectively). In terms of disc and foraminal height, the OLIF L5-S1 group showed significant greater increase of posterior disc height and foraminal height (p=0.01 and 0.00). There was no significant differences between the two groups in mean VAS and ODI score over the follow-up period. Conclusion This study demonstrates that both OLIF L5-S1 group and TLIF L5-S1 group had similar ability of achieving lumbopelvic alignment however, increase of foraminal height was greater in patients with OLIF L5-S1 group