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Ionic thermoelectric supercapacitors (ITESCs) produce orders of magnitude higher voltages than those of conventional thermoelectrics (TEs) based on the thermo-diffusion of electrons/holes and are therefore attractive for converting low-grade heat into electricity. The stretchability and stability of the whole ITESC are important for wearable heat harvesting applications. Recent studies on ITESC have focused on stretchable ionic TE electrolytes with a giant Seebeck coefficient, but there are no reports of fully stretchable ITESCs for wearable heat harvesting devices due to the lack of stretchable electrodes and stretchable ionic TE electrolytes with stability. Herein, we present a fully stretchable ITESC composed of stable high-performance ionic thermoelectric elastomer (ITE) electrolyte and stretchable gold nanowire (AuNW) electrodes. The ITE shows excellent air stability (> 60 d) in comparison to hydrogel-based electrolytes that are susceptible to dehydration in ambient conditions. Furthermore, the ITE exhibits an apparent thermopower up to 38.9 mV K–1 and ionic conductivity of 3.76 × 10–1 mS cm–1, which both are maintained up to a tensile strain of 250%. Finally, a fully stretchable ITESC with AuNW electrodes is developed which can harvest energy from thermal gradients during deformations. [Display omitted] • Ionic thermoelectric elastomer was made of polyethylene glycol diacrylate/2-hydroxyethyl acrylate network with ionic liquid. • The ITE shows excellent air and thermal stability in comparison to hydrogel-based electrolytes. • Thermopower (38.9 mV K–1) and ionic conductivity (3.76 × 10–1 mS cm–1) were obtained. • Ionic thermoelectric performances were maintained up to a tensile strain of 250%. • A stretchable ionic thermoelectric supercapacitor (ITESC) with the ITE and AuNW electrodes was developed. • The stretchable ITESC potentially offers a wearable heat harvesting device on the human epidermis. [ABSTRACT FROM AUTHOR]

Self-powered user-interactive displays that facilitate the visualization of human information acquired by sensors are of great interest in emerging human–machine interface technology with efficient energy consumption. Herein, a self-powered motion-sensing display capable of simultaneously detecting and visualizing finger motions is presented. Our device is based on a one-dimensional photonic crystal of an interpenetrated hydrogel network block copolymer (IHN-BCP) consisting of alternating water-absorbable and non-absorbable lamellae. Triboelectrification is achieved as a function of relative humidity from 30% to 80%. The direct visualization of the humidity is also achieved through the humidity-dependent structural color of the photonic crystal in the full visible range. Furthermore, the humidity-responsive triboelectrification and structural color of our IHN-BCP photonic crystal facilitates the development of a self-powered finger motion-sensing display where diverse gestures of a finger with natural humidity are quantitatively recognized, such as vertical and sliding motion of the finger with simultaneous visualization of the motions in both contact and non-contact modes. Self-powered finger motion-sensing display capable of simultaneously detecting and visualizing finger motions is developed, based on the one-dimensional photonic crystal of a self-assembled block copolymer. The humidity-responsive triboelectrification and structural color of our photonic crystal allows the quantitative sensing and visualization of diverse gestures of a finger with natural humidity. [Display omitted] • We demonstrate self-powered finger motion-sensing display based on self-assembled block copolymer photonic crystal • We utilize humidity-dependent triboelectrification and structural color of the photonic crystal in finger motion. • Self-powered triboelectric sensing is accomplished with simultaneous evolution of structural color in various finger motions. [ABSTRACT FROM AUTHOR]

Policosanols have hypocholesterolemic activity; however, the molecular mechanism of the policosanol effects is currently poorly characterized. We hypothesized that hexacosanol, a policosanol compound derived from barley sprout, may decrease cellular and plasma cholesterol levels; we thus investigated the hypocholesterolemic activity and mechanism of hexacosanol on both hepatocytes and high-fat–induced obese C57BL/6J mice. The reduction of total cholesterol, free cholesterol, and cholesteryl ester concentrations was confirmed in hexacosanol-stimulated hepatocytes (−38%, −33%, and −53%, respectively). Plasma, hepatic cholesterol concentrations, and hepatic steatosis were significantly reduced in high-fat–fed mice orally administered with hexacosanol (0.7 mg/kg body weight a day) for 8 weeks compared with those of vehicle-fed control mice (−15% and −40%, respectively). Hexacosanol in fact bound to the allosteric regulation site of AMP-activated protein kinase (AMPK)- β subunit and thus activated AMPK that inhibited the activity of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase by inhibitory phosphorylation. In addition, activation of AMPK by hexacosanol induced hepatic autophagy activity, which could further reduce hepatic lipid accumulation. Alternatively, hexacosanol suppressed the nuclear translocation and activation of sterol regulatory element-binding protein-2 (SREBP-2), a key transcription factor in cholesterol biosynthesis. These results collectively suggest that hexacosanol is a major hypocholesterolemic compound in barley sprouts with regulation of AMPK activation and SREBP-2 suppression. These suppress 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase at both mRNA expression and protein activity levels. In conclusion, hexacosanol activates AMPK and hepatic autophagy and inhibits SREBP2, resulting in hypocholesterolemic activities and improvement of hepatic steatosis. [ABSTRACT FROM AUTHOR]

Olfactory receptors (ORs) comprise the largest G protein-coupled receptor gene superfamily. Recent studies indicate that ORs are also expressed in non-olfactory organs, including metabolically active tissues, although their biological functions in these tissues are largely unknown. In this study, OR1A1 expression was detected in HepG2 liver cells. OR1A1 activation by (−)-carvone, a known OR1A1 ligand, increased the cyclic adenosine monophosphate (cAMP), but not intracellular Ca 2+ concentration, thereby inducing protein kinase A (PKA) activity with subsequent phosphorylation of cAMP response element-binding protein (CREB) and upregulation of the CREB-responsive gene hairy and enhancer of split (HES)-1, a corepressor of peroxisome proliferator-activated receptor-γ (PPAR-γ) in hepatocytes. In (−)-carvone-stimulated cells, the repression of PPAR-γ reduced the expression of the target gene, mitochondrial glycerol-3-phosphate acyltransferase, which encodes a key enzyme involved in triglyceride synthesis. Intracellular triglyceride level and lipid accumulation were reduced in cells stimulated with (−)-carvone, effects that were diminished following the loss of OR1A1 function. These results indicate that OR1A1 may function as a non-redundant receptor in hepatocytes that regulates the PKA-CREB-HES-1 signaling axis and thereby modulates hepatic triglyceride metabolism. [ABSTRACT FROM AUTHOR]