Stimulation of platelets by thrombin leads to an increased association of activated phosphoinositide 3-kinase (PI 3-K) with a membrane cytoskeletal fraction (CSK). Activation of PI 3-K is dependent upon GTP-binding protein(s), since PI 3-K in permeabilized platelets is stimulated by GTP gamma S (guanosine 5'-3-O-(thio)triphosphate), and stimulation of platelet cytosolic PI 3-K by GTP gamma S requires a functional small G-protein, Rho. Recent reports indicate that cytosolic PI 3-Ks can also be activated by the beta gamma subunits of heterotrimeric G-proteins (G beta gamma). We now report that the activated PI 3-K that is associated with CSK can be inhibited by a recombinant protein containing the G beta gamma-binding pleckstrin homology domain of beta-adrenergic receptor kinase 1 (beta ARK-PH). Inhibition is blocked by G beta gamma. PI 3-K in nonactivated platelet CSK is activated by GTP gamma S but unaffected by beta ARK-PH or G beta gamma. Western blots indicate that activated platelet CSK contains a novel 110-kDa PI 3-K(gamma) that has been shown to be stimulated by G beta gamma and to lack binding sites for the 85-kDa subunit of conventional PI 3-K. PI 3-K in immunoprecipitates obtained via p85 subunit-directed antibodies can be activated by GTP gamma S but not by G beta gamma. PI 3-K that is stimulatable by G beta gamma remains soluble, as does PI 3-K(gamma), and is unaffected by Rho. In contrast, ADP-ribosylation of Rho present in p85 immunoprecipitates is inhibitory. Further, activation of PI 3-K in permeabilized platelets exposed to thrombin or GTP gamma S is inhibited by beta ARK-PH and/or Rho-specific ADP-ribosylating enzymes. We conclude that Rho and G beta gamma each, respectively, contributes to the activation of different PI 3-Ks (p85-containing heterodimer and PI 3-K (gamma)) in thrombin-stimulated platelets.

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The simple ABO3 and A-site-ordered AA′3B4O12 perovskites represent two types of classical perovskite functional materials. There are well-known simple perovskites with ferroelectric properties, while there is still no report of ferroelectricity due to symmetry breaking transition in A-site-ordered quadruple perovskites. Here we report the high pressure synthesis of an A-site-ordered perovskite PbHg3Ti4O12, the only known quadruple perovskite that transforms from high-temperature centrosymmetric paraelectric phase to low-temperature non-centrosymmetric ferroelectric phase. The coordination chemistry of Hg2+ is changed from square planar as in typical A-site-ordered quadruple perovskite to a rare stereo type with 8 ligands in PbHg3Ti4O12. Thus PbHg3Ti4O12 appears to be a combinatory link from simple ABO3 perovskites to A-site-ordered AA′3Ti4O12 perovskites, sharing both displacive ferroelectricity with former and structure coordination with latter. This is the only example so far showing ferroelectricity due to symmetry breaking phase transition in AA′3B4O12-type A-site-ordered perovskites, and opens a direction to search for ferroelectric materials.

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Carbon-based matrix is known to exert a profound influence on the stability and activity of a supported molecular catalyst for electrochemical CO2 reduction reaction (eCO2RR), while regulating the interfacial π–π interaction by designing functional species on the carbon matrix has seldom been explored. Herein, promoted π electron transfer between a graphene substrate and cobalt phthalocyanine (CoPc) is achieved by introducing abundant intrinsic defects into graphene (DrGO), which not only generates more electrochemically active Co sites and leads to a positive shift of the Co2+/Co+ reduction potential but also enhances the CO2 chemical adsorption. Consequently, as compared to the defect-free counterpart rGO-CoPc, DrGO-CoPc could yield CO with a Faradaic efficiency (FECO) higher than 85% in a wide potential range from −0.53 to −0.88 V, and the largest FECO and partial CO current density (J CO) achieve 90.2% and 73.9 mA cm–2, respectively. More importantly, both FECO and J CO can be dramatically improved when conducting eCO2RR in an ionic liquid-based electrolyte, for which FECO is higher than 90.0% in a wide potential range of 600 mV, with the peak J CO of up to 113.6 mA cm–2 in an H-type cell. The excellent eCO2RR performance of DrGO-CoPc rates itself as one of the best immobilized molecular catalysts.

Lipid metabolism is coordinately regulated through signaling networks that integrate biochemical pathways of fat assimilation, mobilization and utilization. Excessive diversion of fat for storage is a key risk factor for many fat-related human diseases. Dietary lipids are absorbed from the intestines and transported to various organs and tissues to provide energy and maintain lipid homeostasis. In humans, disparity between triglycerides (TG) synthesis and removal, via mitochondrial β-oxidation and VLDL (very low density lipoprotein) secretion, causes excessive TG accumulation in the liver. The mutation in Caenorhabditis elegans KLF-3 leads to high TG accumulation in the worm's intestine. Our previous data suggested that klf-3 regulates lipid metabolism by promoting fatty acid β-oxidation. Depletion of cholesterol in the diet has no effect on fat deposition in klf-3 (ok1975) mutants. Addition of vitamin D in the diet, however, increases fat levels in klf-3 worms. This suggests that excess vitamin D may be lowering the rate of fatty acid β-oxidation, with the eventual increase in fat accumulation. We also demonstrate that mutation in klf-3 reduces expression of C. elegans dsc-4 and/or vit genes, the orthologs of mammalian microsomal triglyceride transfer protein and apolipoprotein B, respectively. Both microsomal triglyceride transfer protein and apolipoprotein B are essential for mammalian lipoprotein assembly and transport, and mutation in both dsc-4 (qm182) and vit-5 (ok3239) results in high fat accumulation in worm intestine. Genetic interactions between klf-3 and dsc-4, as well as vit-5 genes, suggest that klf-3 may have an important role in regulating lipid assembly and secretion.

Concrete Canvas (CC) is a 3D spacer fabric-reinforced cement-based composite, prepared through filling cement-based composite powder into fabric via the porous surface of 3D spacer fabric. When hardened by water, CC forms a water-proof, fire-resistant, and durable concrete layer with outstanding mechanical properties. So far, CC has been applied in inflatable tents, slope protection, structure reinforcement and repair, ditch lining, and other engineering projects, as well as furniture and artwork design. Existing studies on CC primarily focus on the modification and optimization of its component materials, and CC reinforcement using externally bonded FRP and aluminum flakes. CC has a broad application and an enormous application potential in emergency engineering, such as the protection of emergency tents and shelters, emergency repair and construction of airport pavement and positional projects; however, it is necessary to improve the compressive strength, flexural strength, wear resistance, anti-penetration performance, and base course bond performance of CC. To that end, research from the perspectives of modifying CC component materials, reinforcement of CC by externally bonded FRP, the improvement of the anchorage method, and the optimization of anchoring primers can be carried out.