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Bir ulkenin ekonomisi yerel politikalar ve zorlayici dis etmenler nedeniyle bir dalgalanma donemine girebilir. Doviz kuru bir ulusun ekonomisini onemli olcude etkileyen ve ekonomiden ayni olcude etkilenen temel etmenlerden biridir. Bu calismada son zamanlardaki Amerikan Dolari/Turk Lirasi paritesindeki istikrarsiz ve hizli degisimden yola cikilarak spekulasyon ve manipulasyonlarin gelismekte olan ekonomilerdeki doviz kuru dinamikleri uzerindeki etkisi incelenmistir. Amerikan dolarinin Turk Lirasi karsisindaki dalgali ve dengesiz yapisi, enflasyon, faiz, kur degisimi ve para piyasasi temel alinarak incelenmistir. Bu bilesenler birbirlerini hem dogrudan hem de geri bildirim donguleri ile dolayli olarak etkiledikleri icin yontem olarak sistem dinamigi yaklasimi secilmistir. Ayni zamanda problemin dogrusal olmayan, dinamik ve karmasik yapisi sistem dinamigi yaklasimini probleme uygun bir yontem haline getirmektedir. Oncelikle temel benzetim kosumu olarak duragan bir piyasa modeli gelisti...

We have combined spectroscopy, chromatography, calorimetry, and small-angle X-ray scattering (SAXS) to provide a comprehensive structural and stoichiometric description of the sodium dodecyl sulfate (SDS)-induced denaturation of the 86-residue α-helical bovine acyl-coenzyme-A-binding protein (ACBP). Denaturation is a multistep process. Initial weak binding of 1–3 SDS molecules per protein molecule below 1.3 mM does not perturb the tertiary structure. Subsequent binding of ∼ 13 SDS molecules per ACBP molecule leads to the formation of SDS aggregates on the protein and changes in both tertiary and secondary structures. SAXS data show that, at this stage, a decorated micelle links two ACBP molecules together, leaving about half of the polypeptide chain as a disordered region protruding into the solvent. Further titration with SDS leads to the additional uptake of 26 SDS molecules, which, according to SAXS, forms a larger decorated micelle bound to a single ACBP molecule. At the critical micelle concentration, we conclude from reduced mobility and increased fluorescence anisotropy that each ACBP molecule becomes associated with more than one micelle. At this point, 56–60 SDS molecules are bound per ACBP molecule. Our data provide key structural insights into decorated micelle complexes with proteins, revealing a remarkable diversity in the different conformations they can stabilize. The data highlight that a minimum decorated micelle size, which may be a key driving force for intermolecular protein association, exists. This may also provide a structural basis for the known ability of submicellar surfactant concentrations to induce protein aggregation and fibrillation.

Tetra- and tri-thioated derivatives of tetrakis[(ethoxycarbonyl)methoxy]tetrathiacalix[4]arenes were synthesized by thionation with Lawesson’s reagent in dry toluene. The prepared compounds’ structures were investigated by FT-IR, 1H NMR, 2D-NMR, MALDI-TOF-MS, and X-ray crystallography.