Solution hybridization drawbacks

Bouin s solution is one of the traditional ways to harden cell pellet. Some cytologists believe it provides the best cellular details, especially nuclear features in cell blocks.28 The major steps are (1) After centrifugation, fix the cell pellet with Bouin s solution. (2) After 2h, discard the solution. (3) Remove the hardened cell pellet from the tube, wrap it with lens paper, and transfer it into a cassette for further processing. We have been using this method for many years. In our experience, most of the time, ICC results are consistent with IHC from the surgical specimen. The biggest drawback of this method is the toxicity of Bouin s fixative which creates biohazard and safety issues for the laboratory. We also found cell blocks gave poor fluorescence in situ hybridization (FISH) results after Bouin s fixation. 

This method can be successfully applied to the case of a solvation effect on the proton chemical shift. However, the effect cannot always be explained by this method. The quantity is very sensitive to the solute-solvent interaction and a serious drawback inherent in the classical-quantum hybrid approach is revealed. The result of ab initio MO analysis for small clusters suggests that electron exchange between solute and solvent is crucial to compute correct values of the chemical shift. A few attempts have been made to overcome this deficiency [18]. 

In recent years, the concept of light construction has led to the development of hybrid structural parts. Using parts made of pure plastic runs into repeated difficulties because of the material s low modulus of elasticity, since the only way to compensate for this drawback is to use much thicker structures. Combinations of sheet metal materials with plastics facilitate new solutions that do justice to the concept of lightweight construction and provide new properties at the same time (sound insulation, thermal conductivity, dynamic stability, corrosion protection). The precondition for successful development of such hybrid structural parts is a reliable bond between the two materials. In certain cases, this must be realized by adhesives that are flexible with regard to the a problem (different heat expansion coefficients of the materials), but still provide high strength levels. 

The study of chemical shift reveals a serious drawback inherent in the classical-quantum hybrid approach. The solvent effect on the oxygen chemical shift showed temperature dependence opposite to corresponding experimental results. An ab initio analysis with a small cluster suggested stongly that the ill behavior is originated from the lack of electron exchange between solute and solvent. Therefore an obvious direction of improvement of the RISM-SCF theory is to take the electron exchange into account. 

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