Supramolecular chemistry and molecular design: self-assembly of molecular squares

Journal ArticleModem supramolecular chemistry has been described as organized polymolecular systems held together by noncovalent interactions and represents one of the major frontiers in the chemical sciences.'-' At present the field is dominated by the hydrogen bonding motif that mimics biological systems and the classical covalent macrocyclics such as crown ethers, cyclophanes, cyclodextrins, calixarenes, etc., that represent the roots of the field!?' Much less is known about the use of coordination and transition metals as a motif for the assembly of supramolecular species

Administration of fructose 1,6-diphosphate during early reperfusion significantly improves recovery of contractile function in the postischemic heart

Objectives: Fructose-1,6-diphosphate is a glycolytic intermediate that has been shown experimentally to cross the cell membrane and lead to increased glycolytic flux. Because glycolysis is an important energy source for myocardium during early reperfusion, we sought to determine the effects of fructose-1,6-diphosphate on recovery of postischemic contractile function, Methods: Langendorff-perfused rabbit hearts were infused with fructose-1,6-diphosphate (5 and 10 mmol/L, n = 5 per group) in a nonischemic model. In a second group of hearts subjected to 35 minutes of ischemia at 37 degrees C followed by reperfusion (n = 6 per group), a 5 mmol/L concentration of fructose-1,6-diphosphate was infused during the first 30 minutes of reperfusion, We measured contractile function, glucose uptake, lactate production, and adenosine triphosphate and phosphocreatine levels by phosphorus 31-nuclear magnetic resonance spectroscopy, Results: In the nonischemic hearts, fructose-1,6-diphosphate resulted in a dose-dependent increase in glucose uptake, adenosine triphosphate, phosphocreatine, and inorganic phosphate levels. During the infusion of fructose-1,6-diphosphate, developed pressure and extracellular calcium levels decreased. Developed pressure was restored to near control values by normalizing extracellular calcium, In the ischemia/reperfusion model, after 60 minutes of reperfusion the hearts that received fructose-1,6-diphosphate during the first 30 minutes of reperfusion had higher developed pressures (83 +/- 2 vs 70 +/- 4 mm Hg, p < 0.05), lower diastolic pressures (7 +/- 1 vs 12 +/- 2 mm Hg, p < 0.05), and higher phosphocreatine levels than control untreated hearts. Glucose uptake was also greater after ischemia in the hearts treated with fructose-1,6-diphosphate. Conclusions: We conclude that fructose-1,6-diphosphate, when given during early reperfusion, significantly improves recovery of both diastolic and systolic function in association with increased glucose uptake and higher phosphocreatine levels during reperfusion

A sustainable marriage of telcos and transp in the era of big data: Are we ready?

The emerging smart city paradigm e.g., intelligent transport, smart grid and participatory sensing etc. is to advance the quality, performance and experience of urban citizten services through greater connectivity. This paradigm needs to collect data from citizens, various devices and assets that could be monitored, processed and analysed for the city governers to make better decision and also more efficiently manage those assests and resources. While the telecommunication and Internet are progressively being over-burdened and congested by the growing data transmission demands. To keep expanding the telecommunications and Internet infrastructures to accomodate these intensive data demands is costly and also the associated energy consumptions and carbon emissions could at long last wind up genuinely hurting the environment. To face this issue in the coming era of big data, we envision it will be best to utilize the established urban transport and road infrastructure and existing daily massive vehicular trips, to complement traditional option for data transmission. After detailing the current state-of-the-art, we consider the main challenges that need to be faced. Moreover, we define the main pillars to integrate the telecommunications and transport infrastructures, and also a proposal for the future urban network architecture