Leptin, a major hormonal product of the adipocyte, regulates appetite and reproductive function through its hypothalamic receptors. The leptin receptor is present in osteoblasts and chondrocytes, and previously we have shown leptin to be an anabolic bone factor in vitro, stimulating osteoblast proliferation and inhibiting osteoclastogenesis. Leptin increases bone mass and reduces bone fragility when administered peripherally but also can indirectly reduce bone mass when administered into the central nervous system. However, data from animal models deficient in either leptin (ob/ob) or its receptor (db/db) remain contradictory. We compared the bone phenotype of leptin receptor-deficient (db/db) and wild-type mice using micro-computed tomographic (mCT) analysis of the proximal tibias and vertebrae. In the tibia, db/db mice had reduced percent trabecular bone volume (13.0 AE

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Increased numbers of adherent invasiveEscherichia coli(AIEC) have been found in Crohn's disease (CD) patients. In this report, we investigate the potential of the probioticEscherichia coliNissle 1917 (EcN) to reduce features associated with AIEC pathogenicity in an already established infection with AIEC reference strain LF82.

Core loss is a significant source of energy loss in electric motor steel laminates. Therefore, there is interest in monitoring the quality and consistency of laminates at various stages of manufacturing. The purpose of this study was to investigate the feasibility of using surface magnetic Barkhausen noise for the evaluation of AC core loss, and further, to examine potential origins of magnetic loss in nonoriented electrical steel. Core loss values were measured by a single sheet tester and Barkhausen noise measurements were performed using pole flux control on eight laminates with various grain size, texture and composition. Magnetocrystalline energy was calculated from X-ray diffraction data to quantify texture. Results demonstrated higher surface Barkhausen emissions for samples with lower core loss. Barkhausen noise analyses were used to examine the interplay among core loss, grain size, magnetocrystalline energy and B-H characteristics. The inverse correlation between core loss and Barkhausen noise emissions was qualitatively explained in terms of the orthogonal vector contribution of microscopic eddy currents to losses associated with bulk currents arising in the sample during magnetization.

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To produce the magnetic core of the electric motors, non-oriented electrical steels (NOES) are used. Recently much attention has been focused on optimizing the efficiency of electric motors and, as such, various materials aspects of NOES are being reexamined. Typically, NOES are used in the form of laminations (~200-1000 μm thick) with an electrically insulating coating applied to the surface. Residual stress is induced during the coating process, which will alter magnetic domain structures of the steel substrate. Variations of the resultant magnetic domains due to coating have been characterized mainly in grain oriented electrical steels [1-3], and only limited numbers of studies are available on non-oriented electrical steels [4]. In this study, the effect of the coating is examined, specifically, its role in creating a residual stress near the coating/steel interface. The stress was investigated by nanoindentation technique. With this method, a tensile stress of ~200 MPa was calculated based on hardness values in the steel substrate, which was linked to the variations in near surface hardness profile, and corresponding magnetic domain structure. The magnetic domain structures were imaged using a field emission scanning electron microscope (FE-SEM).