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With about two-thirds of all used energy being lost as waste heat, there is a compelling need for high-performance thermoelectric materials that can directly and reversibly convert heat to electrical energy. However, the practical realization of thermoelectric materials is limited by their hitherto low figure of merit, ZT, which governs the Carnot(More)
Ghrelin, an orexigenic hormone produced by the stomach, is secreted in anticipation of scheduled meals and in correlation with anticipatory locomotor activity. We hypothesized that ghrelin is directly implicated in stimulating locomotor activity in anticipation of scheduled meals. To test this hypothesis, we observed 24 h patterns of locomotor activity in(More)
Ghrelin is an orexigenic stomach peptide previously found to be important for the full display of anticipatory locomotor activity and hypothalamic neuronal activation that precedes a daily scheduled meal in mice. Ghrelin is also important for food-related motivation and seems to have direct effects in the mesocorticolimbic dopamine reward system. Here we(More)
Food anticipation and its behavioural manifestation, food anticipatory activity (FAA), require entrainment of a suprachiasmatic nucleus (SCN) independent circadian mechanism, a food entrainable oscillator (FEO), with an unknown neural substrate. While the FEO entrains to fasting/feeding related cues and drives FAA independently of the pacemaker in the SCN,(More)
Ghrelin is an orexigenic hormone produced by the stomach. Ghrelin, however, may also be a modulator of the circadian system given that ghrelin receptors are expressed in the master clock, the suprachiasmatic nucleus (SCN) and several outputs of this region. To investigate this, we performed analyses of running wheel activity and neuronal activation in wild(More)
1.—Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208-3108, USA. 2.—Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113, USA. 3.—Northwestern Center for Atom-Probe Tomography, 2220 Campus Drive, Evanston, IL 60208-3108, USA. 4.—Present address: Groupe de(More)
Atom-probe tomography (APT) is utilized to characterize the dopant distribution in two thermoelectric materials systems: (1) PbTe-2 mol.%SrTe1 mol.%Na2Te, and (2) codoped PbTe-1.25 mol.%K-1.4 mol.%Na. We observe the presence of Na-rich precipitates of a few nanometers in diameter in both systems. Both concentration frequency distribution analyses and(More)
The morphology of crystalline precipitates in a solid-state matrix is governed by complex but tractable energetic considerations driven largely by volume strain energy minimization and anisotropy of interfacial energies. Spherical precipitate morphologies are favored by isotropic systems, while anisotropic interfacial energies give energetic preference to(More)
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