NUMERICAL STUDY OF RADIATIVE TRANSPORT HYDRODYNAMICS,AND CHEMICAL KINETICS IN A PHOTODISSOCIATION ATOMIC IODINE AMPLIFIER

Index-of-refraction changes induced by hydrodynamic activity have been blamed for poor beam quality in photodissociation lasers. Until recently, the pump field, hydrodynamics, chemical kinetics, and the losing field have been decoupled in theoretical models because of the wide range of time scales on which they act. Although these mechanisms occur at varying time scales ranging over seven orders of magnitude (subnanosecond to milliseconds), each mechanism strongly affects the others. In this paper we present a model that first couples the pump field, chemical kinetics, and hydrodynamics in the form of implicit and explicit finite-difference equations. We then couple in the laser field to show that index-of-refraction changes induced by radiative transfer degrade peak beam intensity     

Synthesis of N-Aryl- and N-alkyl-Substituted Imidazolium Silver Complexes: Cytotoxic Screening by Using Human Cell Lines Modelling Acute Myeloid Leukaemia

A series of N-aryl- and N-alkyl substituted imidazoles has been synthesised and complexed with Ag⁺ to obtain silver-NHC complexes of the form [Ag(NHC)₂]X. These silver-NHC complexes were tested in vitro against the human cell lines HL-60 and MOLM-13, which both model acute myeloid leukaemia (AML). A substantial difference in cytotoxicity was revealed varying in the range 13–4 μM and 22–9 μM for HL-60 and MOLM-13, respectively. Furthermore, this study revealed that when an alkyl group is installed on the imidazole scaffold, its position substantially influences the cytotoxicity of the corresponding silver NHC complex.     

Comparison of Different Measurement Protocols in Electrical Capacitance Tomography Using Simulations

A major problem in electrical process tomography is that there exist relatively few measurement variables, as compared with the desired resolution of the reconstructed image. This, in addition to the ill-behaved inverse problem involved, makes the image reconstruction problem difficult and severely underdetermined. Using more complex measurement protocols, in addition to an increased number of electrodes, introduces smaller rotational steps of the electric field. More information about the material distribution is obtained, and an increase in the image fidelity may be expected. In this paper, the image fidelity using protocol 3 is compared with the results using the conventional protocol 1. In addition, some performance metrics to assess the fidelity of the protocols are used in the final stage of the analysis. The results are based on simulations using COMSOL Multiphysics and MATLAB.     

Domain Decomposition Models for Parallel Monte Carlo Transport

We present a strategy for parallelizing computations that use the transport method. It combines spatial domain decomposition with domain replication to realize the scaling benefits of replication while allowing for problems whose computational mesh will not fit in a single processor's memory. The mesh is decomposed into a small number of spatial domains—typically fewer domains than there are processors—and heuristics are used to estimate the computational effort required to generate the solution in each subdomain using Monte Carlo. That work estimate determines the number of times a subdomain is replicated relative to the others. Timing of runs for two problems show that the new method scales better than traditional domain decomposition.     

Prostaglandin F2alpha as a mediator of pulmonary changes during platelet aggregation

Increases in pulmonary arterial pressure, tracheal insufflation pressure, and blood levels of the prostaglandin F2alpha metabolite, 15-keto-13, 14-dihydro F2alpha, were observed after protamine chloride or thrombin-induced platelet aggregation and release reaction in dogs. These effects were largely eliminated after administration of acetylsalicylic acid, an inhibitor of prostaglandin synthesis. The platelet aggregation was not noticeably affected. It is suggested that release of prostaglandin F2alpha from platelets is an important factor for the pulmonary changes during induced platelet aggregation. The necessity of measuring metabolite levels, rather than prostaglandin F2alpha levels, in blood during in vivo conditions is demonstrated.