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Cardiopulmonary bypass (CPB) can alter pharmacokinetic (PK) parameters and the drug may adsorb to the CPB device, altering exposure. Cefazolin is a beta‐lactam antibiotic used for antimicrobial prophylaxis during cardiac surgery supported by CPB. Adsorption of cefazolin could result in therapeutic failure. An ex vivo study was undertaken using CPB devices primed and then dosed with cefazolin and samples were obtained over 1 hour of recirculation. Twelve experimental runs were conducted using different CPB device sizes (neonate, infant, child, and adult), device coatings (Xcoating™, Rheoparin®, PH.I.S.I.O), and priming solutions. The time course of saturable binding, using Bmax (binding capacity), Kd (dissociation constant), and T2off (half‐time of dissociation), described cefazolin adsorption. Bmax estimates for the device sizes were neonate 40.0 mg (95% CI 24.3, 67.4), infant 48.6 mg (95% CI 5.97, 80.2), child 77.8 mg (95% CI 54.9, 103), and adult 196 mg (95% CI 191, 199). The Xcoating™ Kd estimate was 139 mg/L (95% CI 27.0, 283) and the T2off estimate was 98.4 min (95% CI 66.8, 129). The Rheoparin® and PH.I.S.I.O coatings had similar binding parameters with Kd and T2off estimates of 0.169 mg/L (95% CI 0.01, 1.99) and 4.94 min (95% CI 0.17, 59.4). The Bmax was small (< 10%) relative to a typical total patient dose during cardiac surgery supported by CPB. A dose adjustment for cefazolin based solely on drug adsorption is not required. This framework could be extended to other PK studies involving CPB. [ABSTRACT FROM AUTHOR]

CO2 and steam/CO2 electroreduction to CO and methane in solid oxide electrolytic cells (SOEC) has gained major attention in the past few years. This work evaluates, for the very first time, the performance of two different ZnO–Ag cathodes: one where ZnO nanopowder was mixed with Ag powder for preparing the cathode ink (ZnOmix–Ag cathode) and the other one where Ag cathode was infiltrated with a zinc nitrate solution (ZnOinf –Ag cathode). ZnOmix–Ag cathode had a better distribution of ZnO particles throughout the cathode, resulting in almost double CO generation while electrolysing both dry CO2 and H2/CO2 (4:1 v/v). A maximum overall CO2 conversion of 48% (in H2/CO2) at 1.7 V and 700 °C clearly indicated that as low as 5 wt% zinc loading is capable of CO2 electroreduction. It was further revealed that for ZnOinf –Ag cathode, most of CO generation took place through RWGS reaction, but for ZnOmix–Ag cathode, it was the synergistic effect of both RWGS reaction and CO2 electrolysis. Although ZnOinf –Ag cathode produced trace amount of methane at higher voltages, with ZnOmix–Ag cathode, there was absolutely no methane. This seems to be due to strong electronic interaction between Zn and Ag that might have suppressed the catalytic activity of the cathode towards methanation. [ABSTRACT FROM AUTHOR]

A novel mixed oxide material, Fe-Ce0.1Zr0.9O2-Ag, has been tested as cathode, for the very first time, for one-step methane synthesis in a single temperature solid oxide electrolyser by electrolysing a H2/CO2 (4:1 v/v) mixture at 500 °C. Maximum methane selectivity and yield were 6.67 % and 2.66 %, respectively, at an applied potential of 1.6 V (corresponding to a current density of 3.94 mAcm-2). CO2 conversion (~ 40 %) was independent of the applied voltage. However, upon increasing the potential, CO% dropped monotonically with a commensurate increase in methane%. Calculations based on oxide ion removal as a function of current density confirmed that under loaded conditions steam generated in situ (via reverse water gas shift and methanation reactions) got electrolysed to H2, which reacted with CO producing more methane. Such excess methane produced purely electrolytically under loaded conditions matched well with the values predicted theoretically assuming that the decrease in CO% was solely due to enhanced methanation. [ABSTRACT FROM AUTHOR]

In this era, information technology is revolutionizing almost every domain of technology and society, whereas the 'complexity revolution' is occurring in science at a silent pace. In this paper, we look at the impact of the two, in the context of supply-chain networks. With the advent of information technology, supply chains have acquired a complexity almost equivalent to that of biological systems. However, one of the major challenges that we are facing in supply-chain management is the deployment of coordination strategies that lead to adaptive, flexible and coherent collective behaviour in supply chains. The main hurdle has been the lack of the principles that govern how supply chains with complex organizational structure and function arise and develop, and what organizations and functionality are attainable, given specific kinds of lower-level constituent entities. The study of Complex Adaptive Systems (CAS), has been a research effort attempting to find common characteristics and/or formal distinctions among complex systems arising in diverse domains (like biology, social systems, ecology and technology) that might lead to a better understanding of how complexity occurs, whether it follows any general scientific laws of nature, and how it might be related to simplicity. In this paper, we argue that supply chains should be treated as a CAS. With this recognition, we propose how various concepts. tools and techniques used in the study of CAS can be exploited to characterize and model supply-chain networks. These tools and techniques are based on the fields of nonlinear dynamics, statistical physics and information theory. [ABSTRACT FROM AUTHOR]