1,14‐Dioxa‐5,10‐di­aza‐2,3:12,13‐dibenzo­cyclo­octadeca‐2,12‐diene monohydrate

The title compound, C₂₂H₃₀N₂O₂·H₂O, is an 18‐membered di­aza‐crown ether ligand containing two ether O and two aza N atoms. In the macrocyclic ring, the mean N⋯O distance is 4.526 (4) Å. The macrocyclic inner‐hole size, estimated as twice the mean distance of the donor atoms from their centroid, is ∼2.29 Å.     

Model validation in operations research

Numerous articles have appeared in the literature expressing different degrees of concern with the methodology of OR in general and with the validation of OR models in particular. Suggestions have been formulated to remove some of the shortcomings of the methodology as currently practised and to introduce modifications in the approach because of the changing nature of the problems tackled. Advances in modeling capabilities and solution techniques have also had considerable impact on the way validation is perceived. Large scale computer-based mathematical models and especially simulation models have brought new dimensions to the notion of validation. Terms like ‘confidence’, ‘credibility and reliability’, ‘model assessment and evaluation’, ‘usefulness and usability of the model’ have become rather common. This paper is an attempt, through an interpretation of the literature, to put model validation and related issues in a framework that may be of use both to model-builders and to decision-makers.     

Interaction of Mitomycin C with DNA Immobilized onto Single‐walled Carbon Nanotube/Polymer Modified Pencil Graphite Electrode

The electrochemical investigation of the interaction between the anticancer drug mitomycin C (MC) and DNA was described using a single‐walled carbon nanotube (SWCNT)/poly(vinylferrocenium) (PVF⁺) modified pencil graphite electrode (PGE). The electrochemical oxidation signals of guanine were monitored before and after the interaction between MC and DNA by using differential pulse voltammetry. The effects of DNA and MC concentration and MC interaction time were examined based on the electrode response. Cyclic voltammetry and electrochemical impedance spectroscopy were used for the characterization of SWCNT/PVF⁺ modified and PVF⁺ modified PGEs. The detection limit corresponded to 625 ng/mL for MC using calf thymus double‐stranded DNA immobilized SWCNT/PVF⁺ modified PGE.     

An Empirical Study on Measuring Industrial Competitiveness

This paper discusses the methodology developed for the Industrial Development Bank of Turkey for the purpose of measuring the competitiveness of local manufacturing firms in foreign markets. First, an industrial competitiveness model which incorporates both the firm's and foreign competititors' input costs, technological characteristics and political-economic environments is summarized. Then an application of this model to 30 selected local firms in textiles, stone and soil, and food industries is described. The results indicate that some of the selected firms are quite competitive in European, North African and Middle Eastern countries, and can export to these markets without much difficulty. Moreover, the methodology employed in this study promises to be useful in identifying the weaknesses and strengths of industries, albeit in general terms, to formulate government policies.     

Content analysis of data envelopment analysis literature and its comparison with that of other OR/MS fields

Content analysis was performed on the data envelopment analysis (DEA) literature appearing in refereed journals. The extant DEA literature, reported in Gattoufi et al was subdivided into two ways. The first considers all articles appearing during the life cycle of 22 selected major DEA publishing journals. The second considers all post-1995 DEA articles. Content was judged on the basis of a two-point scale representing advancements in theory; a five-point scale indicating contributions to practice; and on seven distinguishable strategies applied by the authors in pursuing their research. Lastly, DEA was compared with similarly obtained results describing the life cycle literatures of flow shop scheduling and of cell manufacturing. This analysis has proven the vitality, robustness, and real-world grounding of DEA on its own and vis-à-vis other OR/MS sub-disciplines. Moreover, the breadth of its diffusion into other disciplines and professions has been shown to be extraordinary.     

Molecular recognition properties of FN3 monobodies that bind the Src SH3 domain

We have constructed a phage-displayed library based on the human fibronectin tenth type III domain (FN3) scaffold by randomizing residues in its FG and BC loops. Screening against the SH3 domain of human c-Src yielded six different clones. Five of these contained proline-rich sequences in their FG loop that resembled class I (i.e., +xxPxxP) peptide ligands for the Src SH3 domain. The sixth clone lacked the proline-rich sequence and showed particularly high binding specificity to the Src SH3 domain among various SH3 domains tested. Competitive binding, loop replacement, and NMR perturbation experiments were conducted to analyze the recognition properties of selected binders. The strongest binder was able to pull down full-length c-Src from murine fibroblast cell extracts, further demonstrating the potential of this scaffold for use as an antibody mimetic.     

Modeling of adsorption and ultrasonic desorption of cadmium(II) and zinc(II) on local bentonite

The adsorption and ultrasonic desorption of toxic heavy metal cations (i.e., Cd(II) and Zn(II)) on natural bentonite have been modeled with the aid of a factorial design approach. The ability of untreated bentonite to remove Cd(II) and Zn(II) from aqueous and acidic solutions at different pH values has been studied for different metal concentrations by varying the amount of adsorbent, temperature, stirring speed, and contact time. The same factors, except stirring speed and metal concentration, were applied in desorption study. Ultrasound power was used for desorption instead of stirring speed. A flame atomic absorption spectrometer was used to measure the cadmium and zinc concentration before and after both experimental study. The highest adsorption for Zn and Cd was 99.85 and 96.84%, respectively, and the highest desorption for Zn and Cd obtained was 66.57 and 51.37%, respectively. It is believed that the models obtained for adsorption and desorption may provide a background for detailed mechanism searches and pilot and industrial scale applications.     

C-bis-pivot lariat ethers: synthesis and spectral investigations on new 15- and 17-membered coronands containing dimethoxyphosphoryl groups

The reactions of dibenzo-diaza crown ethers (coronands) (1 and 2) with dimethylphosphite led to the formation of the mixture of meso and racemic C-bis-pivot lariat ethers (3 and 4) containing dimethoxyphosphoryl groups. We have failed to make the resolution of the mixture, nevertheless, the detailed characterization and spectral investigations of compounds 3 and 4 have been made by elemental analyses, FTIR, (1)H NMR, (13)C NMR, (31)P NMR, COSY, DEPT, HETCOR and HMBC spectral data. The salient features of the spectral data of these compounds have been presented.