Temporary Protection and Technology Choice Under the Learning Curve

No abstract.

Structural and Correlation Effects in the Itinerant Insulating Antiferromagnetic Perovskite NaOsO3

The orthorhombic perovskite NaOsO3 undergoes a continuous metal-insulator transition (MIT), accompanied by antiferromagnetic (AFM) order at T_N=410 K, suggested to be an example of the rare Slater (itinerant) MIT. We study this system using ab initio and related methods, focusing on the origin and nature of magnetic ordering and the MIT. The rotation and tilting of OsO6 octahedra in the GdFeO3 structure result in moderate narrowing the band width of the t_{2g} manifold, but sufficient to induce flattening of bands and AFM order within the local spin density approximation (LSDA), where it remains metallic but with a deep pseudogap. Including on-site Coulomb repulsion U, at U_c ~2 eV a MIT occurs only in the AFM state. Effects of spin-orbit coupling (SOC) on the band structure seem minor as expected for a half-filled $t_{2g}^{3}$ shell, but SOC doubles the critical value U_c necessary to open a gap and also leads to large magnetocrystalline energy differences in spite of normal orbital moments no greater than 0.1$\mu_B$. Our results are consistent with a Slater MIT driven by magnetic order, induced by a combination of structurally-induced band narrowing and moderate Coulomb repulsion, with SOC necessary for a full picture. Strong p-d hybridization reduces the moment, and when bootstrapped by the reduced Hund's rule coupling (proportional to the moment) gives a calculated moment of ~1 $\mu_B$, consistent with the observed moment and only a third of the formal $d^3$ value. We raise and discuss one important question: since this AFM ordering is at q=0 (in the 20 atom cell) where nesting is a moot issue, what is the microscopic driving force for ordering and the accompanying MIT?Comment: 9 page

Origin and Characterization of Multipotential Mesenchymal Stem Cells Derived from Adult Human Trabecular Bone

Much of the knowledge regarding the regulatory pathways for adult stem cell self-renewal and differentiation has been obtained from the results of in vitro cultures. However, it is unclear if adult stem cells are controlled in the same way under physiological conditions. We examined this issue with respect to the migration of stem cells to tissue injury and how switch from a migratory state to one of proliferation wherein they participate in development. Building on our previous identification of multipotent stem cells in trabecular bone, we have examined the in vitro behavior of these cells within the bone milieu. We found that cell proliferation is inhibited within the trabecular bone niche as cells migrate out of the trabecular bone prior to proliferation. Additionally, multiple cell types were detected in adult trabecular bone, including osteoblasts, osteoclasts, endothelial cells, and Stro-1-positive mesenchymal stem cells. Furthermore, we demonstrated that Stro-1-positive cells migrated out of their native bone niche to generate multipotential stem and progenitor cells during in vitro culture. We conclude that self-renewal and differentiation of adult stem cells in connective tissues are tightly controlled and separately orchestrated processes. A regulatory network of extrinsic factors and intrinsic signals acts to stimulate the exit of stem cells from their niche so that they can localize to sites of wound healing, where they participate in development after functional differentiation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63409/1/scd.2005.14.712.pd

SNP Assay Development for Linkage Map Construction, Anchoring Whole-Genome Sequence, and Other Genetic and Genomic Applications in Common Bean.

A total of 992,682 single-nucleotide polymorphisms (SNPs) was identified as ideal for Illumina Infinium II BeadChip design after sequencing a diverse set of 17 common bean (Phaseolus vulgaris L) varieties with the aid of next-generation sequencing technology. From these, two BeadChips each with >5000 SNPs were designed. The BARCBean6K_1 BeadChip was selected for the purpose of optimizing polymorphism among market classes and, when possible, SNPs were targeted to sequence scaffolds in the Phaseolus vulgaris 14× genome assembly with sequence lengths >10 kb. The BARCBean6K_2 BeadChip was designed with the objective of anchoring additional scaffolds and to facilitate orientation of large scaffolds. Analysis of 267 F2 plants from a cross of varieties Stampede × Red Hawk with the two BeadChips resulted in linkage maps with a total of 7040 markers including 7015 SNPs. With the linkage map, a total of 432.3 Mb of sequence from 2766 scaffolds was anchored to create the Phaseolus vulgaris v1.0 assembly, which accounted for approximately 89% of the 487 Mb of available sequence scaffolds of the Phaseolus vulgaris v0.9 assembly. A core set of 6000 SNPs (BARCBean6K_3 BeadChip) with high genotyping quality and polymorphism was selected based on the genotyping of 365 dry bean and 134 snap bean accessions with the BARCBean6K_1 and BARCBean6K_2 BeadChips. The BARCBean6K_3 BeadChip is a useful tool for genetics and genomics research and it is widely used by breeders and geneticists in the United States and abroad

Low Intensity Resistance Exercise Training with Blood Flow Restriction: Insight into Cardiovascular Function, and Skeletal Muscle Hypertrophy in Humans

Attenuated functional exercise capacity in elderly and diseased populations is a common problem, and stems primarily from physical inactivity. Decreased function and exercise capacity can be restored by maintaining muscular strength and mass, which are key factors in an independent and healthy life. Resistance exercise has been used to prevent muscle loss and improve muscular strength and mass. However, the intensities necessary for traditional resistance training to increase muscular strength and mass may be contraindicated for some at risk populations, such as diseased populations and the elderly. Therefore, an alternative exercise modality is required. Recently, blood flow restriction (BFR) with low intensity resistance exercise (LIRE) has been used for such special populations to improve their function and exercise capacity. Although BFR+LIRE has been intensively studied for a decade, a comprehensive review detailing the effects of BFR+LIRE on both skeletal muscle and vascular function is not available. Therefore, the purpose of this review is to discuss previous studies documenting the effects of BFR+LIRE on hormonal and transcriptional factors in muscle hypertrophy and vascular function, including changes in hemodynamics, and endothelial function

CP violation in associated charged Higgs boson production with a single top at the LHC

We explore the CP violation in the charged Higgs production associated with a top quark at the LHC in the MSSM. The supersymmetric phases of gaugino masses and trilinear $A$ terms lead to a CP violating asymmetry of the cross section in the $p p \to g b \to t H^\pm$ process through loop corrections to the $tbH^\pm$ vertex. We find that a CP violation more than 10 % is possible if the charged Higgs boson is heavy enough.Comment: 8 pages including 5 eps figures, JHEP, corrections mad