20 research outputs found
Noninvasive electromyometrial imaging of human uterine maturation during term labor
Electromyometrial imaging (EMMI) was recently developed to image the three-dimensional (3D) uterine electrical activation during contractions noninvasively and accurately in sheep. Herein we describe the development and application of a human EMMI system to image and evaluate 3D uterine electrical activation patterns at high spatial and temporal resolution during human term labor. We demonstrate the successful integration of the human EMMI system during subjects\u27 clinical visits to generate noninvasively the uterine surface electrical potential maps, electrograms, and activation sequence through an inverse solution using up to 192 electrodes distributed around the abdomen surface. Quantitative indices, including the uterine activation curve, are developed and defined to characterize uterine surface contraction patterns. We thus show that the human EMMI system can provide detailed 3D images and quantification of uterine contractions as well as novel insights into the role of human uterine maturation during labor progression
New genetic loci link adipose and insulin biology to body fat distribution.
Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms
Lipase immobilization on ionic liquid-modified magnetic nanoparticles: Ionic liquids controlled esters hydrolysis at oil-water interface
Ester hydrolysis at oilwater interface by lipase covalently immobilized on ionic liquid-modified magnetic nanoparticles was investigated. Magnetic supports with a diameter of 1015 nm were synthesized by covalent binding of ionic liquids (chain length C4 and C8 and anions Cl-, BF4-, and PF6-) on the surface of Fe3O4 nanoparticles. Lipase was covalently immobilized on Fe3O4 nanoparticles using ionic liquids as the coupling reagent. Ionic liquid-modified magnetic nanoparticle-grafted lipase preferentially located at the oilwater interface. It has higher catalytic activity than its native counterpart. A modified MichaelisMenten model was used to elucidate the effect of stirring rate, aqueousorganic phase ratio, total amount of enzyme, and ester chain length. The influences of these conditions on esters hydrolysis at oilwater interface were consistent with the introduction of the ionic liquids interlayer. Ionic liquids could be used to control the oilwater interfacial characteristics during lipase catalyzed hydrolysis, and thus control the behavior of immobilized lipase. (C) 2011 American Institute of Chemical Engineers AIChE J, 201
La promoted Ni0-Ni δ+ synergistic interaction for rapid and deep hydrogenation of liquid organic hydrogen carriers
The development of cost-effective, efficient and stable catalysts for liquid organichydrogen carriers (LOHC) is crucial for large-scale hydrogen storage. Herein, weintroduced La species into Ni/Al2O3 via co-precipitation method, yielding La-Ni/Al2O3 catalysts. Such catalysts demonstrated exceptional performance and durability in hydrogenating various LOHC candidates. Their hydrogenation capabilities surpassed most state-of-the-art and commercial catalysts, attributing to the homogenous formation of ultrafine nanoparticles induced by La species, prevention of producing unfavorable components, optimal microstructural distributions and balanced dispersion of acid sites. DFT calculations indicated that Ni-NiO(002) interface played crucial roles in modulating the electron deficiency of surface Ni atoms. The synergistic effect of Ni0-Niδ+ shifts the d-band center of Ni closer to the Fermi level, enhancing the catalyst’s adsorption capacity of intermediates and achieving higher activity toward activation ofbenzene and pyrrole ring, therefore leading to rapid and deep LOHC hydrogenation.The resultant catalysts exhibited great potentials for industrial applications
Expeditious diastereoselective construction of a thiochroman skeleton via a cinchona alkaloid-derived catalyst
10.1039/c1ob06497eOrganic and Biomolecular Chemistry10136-3