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The methods described in the preceding paper have been used to calculate the composition of a strip of once folded molecules of n-C294H590. The fraction of cilia and of stems participating in adjacent and nonadjacent reentry were calculated as a function of undercooling in regime I. Two cases corresponding to crystallization from the melt and one corresponding to dilute solution were considered. The results are strongly dependent on the relative rates of deposition of a stem from the liquid phase and the folding and reentry of the dangling half of an already attached molecule. The rate constants for adjacent and nonadjacent reentry were taken to be the same except that nonadjacent reentry leaves a hole in the strip. The undercooling below the melting point of the extended chain crystal at which the growing strip is in equilibrium with its environment is shown to be determined by all the imperfections in the strip, and particularly by the free energy of mixing. In all cases, the fractions of adjacent and nonadjacent reentry at this equilibrium undercooling are approximately equal and the fraction of cilia is a maximum. At higher undcoolings, the fraction of adjcent reentry rises, while the fractions of cilia and nonadjacent reentry fall, the exact behavior depending on the solution concentration and hence the relative rates of stem deposition from the liquid phase and of folding. This behavior is correlated with the free energy of mixing. [ABSTRACT FROM AUTHOR]

Clinical and experimental data show that beta-IFN enhances the effect of tamoxifen on advanced breast cancer. There is a similarity between breast and liver as far as the proliferating effect on normal and neoplastic tissue of estrogen and progestin receptors is concerned. The authors tested this pharmacological association in unresectable liver neoplasms. They considered 76 (not randomized) patients affected with HCC; 38 were treated by trans-arterial chemoembolization (TACE) and 38 to beta-INF and tamoxifen (the 2 groups were comparable according to age, sex, Child-Pugh score, Okuda and TNM stages, cirrhosis etiology). The treatment response (positive when a tumor diameter decreased or stabilization was observed) was similar in the two groups; in the TACE group, the presence of a peritumoral capsula had a significant influence on survival (p < 0.02); on the other hand, in the patients treated with beta-INF and tamoxifen important factors for a better prognosis were the TNM stage (I and II, p < 0.02) and a symptom-free condition (p < 0.04). The authors believe the beta-INF and tamoxifen treatment could represent an effective alternative in the management of unresectable HCC. A better knowledge of the presence and meaning of estrogen and progestin receptors in the neoplastic tissue may allow a better selection of patients.

A model is proposed to estimate the surface free energy of a small polymer crystal with numerous emergent cilia. For such a model the partition function of a polymer constrained to remain in a cone is computed. The partition function of the polymer in a cone is found to behave similarly to the polymer in a wedge discussed by Lauritzen and DiMarzio [1]. The estimated end surface free energy per unit area for the small extended chain crystal is found to increase with increasing area, implying the presence of cumulative surface stress in such crystals. The forces between the cilia are reduced if folds are inserted in the surface.

The probability distribution for the end-to-end length of a polymer of N segments confined in a wedge of interior angle α is obtained (2 π ≥· α > 0). The result is used to evaluate the partition function, Q , for the cases: (1) one end free - one end tied to the vertex, Q is proportional to γ N N -π/2α both ends tied to each other at the vertex, Q , is proportional to γ N N -3/2 - π/α .

The Wiener integral (path integral, functional integral) technique is used to determine the equation describing the probability distribution of a polymer molecule immersed in a non-uniform distribution of monomer units. This result should be useful whenever there is a spatial variation of polymer density such as at an interface or surface.

The view that the glass transition has a thermodynamic basis is extended to a cross-linked rubber. The elevation of the second-order transition temperature as a function of the number of cross-links is found to be ( T(X) - T(0) )/ T (0) = KX /1 - KX , where T(X) is the transition temperature for a rubber with degree of cross-linking X . The constant K is to first order independent of material. Also a relation involving no adjustable parameter is derived for the ratio of second-order transition temperatures to deformation. It is T (λ)/ T (1)=exp ( G (Σλ i 2 - 3)/2Δ C p T 0 ) where Δ C p is the value of the specific heat discontinuity per cm 3 at the transition and T 0 is the temperature at which the modulus G is measured. Available experimental evidence from five separate investigations agrees with these predictions.

The kinetics of crystallization of a binary mixture of n -paraffins is treated using a theory for the rate of growth of chains in multicomponent systems. The kinetic chain is considered to be a strip of crystalline material composed of molecules of both components that is growing on a substrate of uniform thickness. This substrate is considered to be a close-packed surface step. Using the binary mixture of C 24 H 50 and C 26 H 54 as an example, the calculations are carried out by an iterative procedure so that the mean thickness of the strip equals that of the substrate. This procedure necessitates modification of the rate constants that would be used without this requirement. The rate of growth of the strips (total flux) is calculated as well as their composition over an appropriate range of temperature and a complete range of liquid compositions. The pair distribution in the strips is also determined. The substrate is assumed to be unkinked in the calculations, whereas the substrate is probably highly kinked in the actual system. For this reason the calculated total flux is probably not representative of the actual crystal growth rate in a binary mixture of C 24 H 50 and C 26 H 54 . It is believed that the calculated compositions are reasonably accurate. For a binary mixture of longer n -paraffins (e.g., C 50 H 102 C 52 H 106 ) the substrate should have many fewer kinks, and the total flux calculated by this theory will be more closely related to actual crystal growth rate studies. However, no data exist for such systems.