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HIV-1 integrase (IN) inhibition of a novel series of quinoline derivatives was investigated. The compounds were designed on the basis of quinoline molecular scaffolds that attempt to mimic the basic naphtyridine motif of the L-870810 HIV-1 IN inhibitor. It appeared that the IN inhibition of the novel compounds was limited by the electroacceptor substitution within quinoline. Although the compounds studied here indicate structural similarity to L-870810, they are much less efficient than this compound. This can be explained by differences in conformations and apparent magnesium complexing ability in the naphtyridine and quinoline based amides.

8-Hydroxy-7-quinaldic acid can be considered as a basic scaffold for all reported styrylquinoline HIV-1 integrase inhibitors. However, when tested in vitro, this compound appeared to be inactive against the enzyme. We have designed and synthesized an improved molecular fragment, i.e. 5-hydroxy-8-nitro-6-quinaldic acid, which appeared to inhibit HIV-1 integrase in vitro.

This document defines the terms most commonly encountered in the field of polymers containing ionizable or ionic groups and polymers containing ions. The scope of the document has been limited to organic polymers. Inorganic materials, such as certain phosphates, silicates, etc., which also may be considered ionic polymers, are excluded from the present document.

The document defines the terms most commonly encountered in the field of polymer reactions and functional polymers. The scope has been limited to terms that are specific to polymer systems. The document is organized into three sections. The first defines the terms relating to reactions of polymers. Names of individual chemical reactions are omitted from the document, even in cases where the reactions are important in the field of polymer reactions. The second section defines the terms relating to polymer reactants and reactive polymeric materials. The third section defines the terms describing functional polymeric materials.

Microcomputer-based control of a signalized urban multi-intersection system is considered. A hierarchical control configuration involving a central controller, which utilizes also a mainframe computer, regional controllers and local controllers at each intersection, is proposed. An optimization procedure, utilizing the mixed-integer programming approach, and maximizing the green light band, is implemented by the central controller for all intersections. The mixed-integer programming algorithm is run on a CDC CYBER 170/720 computer. A complete hardware design of the controllers at all levels, utilizing Intel 8085 (for the central controller) and Intel 8051 (for the regional and local controllers) has been performed. A software package for all controllers has been prepared. The whole system has been simulated on the CYBER 170 and on an Intel MDS-251 Development System.

The paper presents the software development project for a microcomputer controlled laser synchronization system. The development is presented in the light of modern software engineering practice. The modular approach is used, where the whole software system is developed as separate modules. All modules can later be independently maintained and modified. Each module is subdivided into separately accessible procedures. The hardware-software interaction is stressed by the presentation of a Phase Lock Loop subsystem in this project. Flow diagrams of a selected software module and one of its procedures are presented.

Abstract.: Natural rubber latex was diluted from its original ca. 61% DRC (Dry Rubber Content) to 10% and the resulting material was studied with respect to its aggregation stability. Two non-ionic surfactants with distinct HLB (hydrophilic–lypophilic balance) and cloud point values were used to stabilize the dilute latex. The stability of the obtained materials was evaluated through the addition of acetic acid solutions of different concentrations, and measurement of the pH and coagulation times of the resulting mixtures. Independently of the nature and concentration of the surfactants, the same behavior was observed for all the systems. All the latex solutions were stable after the addition of the acetic acid solutions for at least thirty days.

The paper constitutes an applications case study involving the design of a microcomputer-based control and synchronization system of two lasers. The main performance specification is that the laser pulses should be synchronized within less that 10ns delay between them to achieve maximum power output. This specification has been achieved in the system designed in the project, constructed and tested in practice. An alternative of using off-the shelf instrumentation for the same purpose has been considered and rejected because of higher cost. The hardware configuration and the system software are described in the paper along with some basic design considerations and decisions implemented in the system's development

The compatibility of PVC with poly(diethylene glycol adipate) Mn = 1500 was evaluated by DSC, indicating a limit value of 15 phr. The behavior of the oligomer as a PVC plasticizer, alone or in combination with dioctylphthalate (DOP), was investigated by measurements such as hardness, glass transition temperature, heat stability, and solvent resistance. In spite of its limited compatibility the oligoester can act as a secondary plasticizer enhancing the overall performance of the compositions.

Microcomputer-based control of the X-Y motion of a sewing head of an industrial sewing machine is considered. A digital controller, replacing a previously used analog one, is designed. It is realized using a Motorola 6801 single-chip microcomputer. Adaptive control of the system is also discussed. In particular the model reference approach, using the Liapunov function, is adopted. A solution using this approach is proposed.

In its first sections, the paper deals with optimum thrust nozzles of given length and exit radius for flows with swirl. The computation is based on a modification of methods familiar for flows without swirl. Rather extensive numerical results show that the swirl does not impair the specific impulse attainable at a given nozzle length. The analysis suggests that the assumption of isentropic continuous flows, on which this approach is based, may sometimes be too restrictive. A survey of plane nozzles shows, on the other hand, that discontinuities need to be admitted only if, besides the length, a rather large radius of the nozzle is prescribed. Discontinuous solutions have been thoroughly investigated by Shmyglevskiy. At least in principle, we use the same line of thought, but considerable simplifications are possible if one starts with the variational formulation of Rao. In its numerical discussion and also in some analytical details, the present paper goes beyond Shmyglevskiy's results. The problem is conveniently discussed in astateplane, which has the local state of the flow (flow direction and speed or Mach number) as independent variables. By taking into account second variations, one can determine the boundary of the region for which continuous solutions give the (local) maximum. This boundary coincides with the locus of points at which the solution in the physical plane would fold back into itself. Another limitation of the original approach emerges if one asks under which conditions the thrust can be increased by admitting along the control surface values of the entropy that are higher than those of the oncoming flow. The conditions for isentropic and nonisentropic jumps are formulated and evaluated next, and a survey of the discontinuities which satisfy conditions for isentropic and also for selected nonisentropic jumps is given. Up to this point, the analysis is concerned only with the state distribution along the control surface. Jumps of the state in the interior require the occurrence of centered compression waves. Sample computations show that, in most cases, flow fields of this character can be generated by the choice of the nozzle shape. In some cases, no nozzle contours exist which generate the optimizing state distribution along the control surface as determined by the present analysis. It would then be necessary to include from the very beginning conditions for the realizability of the flow field.

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Presents letters sent to the editor regarding previous articles from this publication or other relevant topics of discussion.

The book consists of selected papers presented at the Second International Conference on Computing Methods in Optimization Problems held in San Remo, Italy, September 9–13, 1968. The purpose of the conference was to review recent advances in computational techniques of optimization problems, applied in a variety of technical areas. Thirty-one papers presented at the conference were selected to be included in this publication. These papers can be subdivided into eight basic categories. This classification and the contents of the papers will be discussed next.