The pressure dependence of the helix-to-coil transition temperature (Tm) of poly[d(A-T)], poly(dA).poly(dT), and poly(dA).poly(dT)2 was studied as a function of sodium chloride concentration. The molar volume change of the transition (delta V) was calculated using the Clapeyron equation and calorimetrically determined enthalpies. The delta V of the transition varied linearly with the logarithm of the salt concentration for both double-stranded polymers. The delta V of poly[d(A-T)] changed from +0.36 to +3.86 cm3 mol-1 as the sodium chloride concentration changed from 0.020 to 1.0 M. For poly(dA).poly-(dT), the delta V varied from +2.60 to +4.59 cm3 mol-1 over the range of 0.020-0.20 M NaCl. No pressure dependence of the van't Hoff enthalpy was observed for the double-helical form of either polymer. The delta V for denaturation of the triple-helical species poly(dA).poly(dT)2 was found to be +7.81 and +10.4 cm3 mol-1 at 1.0 and 3.0 M NaCl, respectively. The observed delta V values are interpreted in terms of changes in the hydration of the polymers arising from release of counterions and changes in the stacking of the bases upon denaturation. Counterion release is assumed to make a net negative contribution to the overall delta V, implying that disruption of the stacking interactions must make a positive volume change to the overall delta V. The difference in the delta V values for the two polymers remains constant as the salt concentration is changed, suggesting a difference in the partial molar volume of their single-stranded forms.(ABSTRACT TRUNCATED AT 250 WORDS)

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Time-dependent shear and mechanical energy loss moduli of chicken breast myosin sols/gels were measured for various protein concentrations and isothermal conditions. Gelation followed secondorder kinetics, with rate constants ranging from 0.0024 to 0.88 mL/(mg min). Rate constants changed in a complex manner with respect to temperature. Gels formed at low temperatures (44-56 °C) developed greater shear modulus values and were more elastic than those formed at higher temperatures (58-70 °C). Higher myosin concentration increased the rate of shear modulus development, and final values were higher. Thermal scanning at 1 °C/min produced only x/2 to 1/ie of the potential shear modulus magnitude based on isothermal heating. Overall, gel rheology was strongly dependent on temperature history.

Modern medicine adopted four presumptions when it evolved from ancient experienced-based mind-body medicine. To understand its failure in finding cures for chronic diseases, we examined four presumptions, and found that statistical population of health properties does not exist for most research purposes, mathematical models are misused to model intensive properties, synthetic drugs are inherently more dangerous than nature-made medicines under their respective application conditions, and reductionist treatments are inferior and inherently dangerous. We found that clinical trials are valid only for research where treatment effect is much stronger than the total effects of all interfering or co-causal factors or errors introduced by misused mathematical models can be tolerated. In all other situations, clinical trials introduce excessive errors and fail to detect treatment effects, or produce biased, incorrect or wrong results. We further found that chronic diseases are manifestation of small departures in multiple process attributes in distinctive personal biological pathways networks, that modern medicine lacks required accuracy for accurately characterizing chronic diseases, and that reductionist treatments are good at controlling symptoms and safe for short term uses. For all stated reasons, as long as modern medicine continues relying on the flawed presumptions, it can never find predictable cures for chronic diseases. By implication, predictable cures to chronic diseases are adjustments to lifestyle, dietary, emotional, and environmental factors to slowly correct departures in process attributes responsible for chronic diseases.

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