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Notes: Investigation of the effects of selected enzymatic pretreatments of alfalfa leaves on plant protein recovery by mechanical expression of cell contents showed significantly higher crude protein recoveries for enzymatically treated extracts as compared with untreated samples. Protein recovery increases were seen for leaves pretreated with a buffered cellulase and a cellulase-pectinase mixture. However, protein recoveries were not increased by pretreatment with a pectinase or a phospholipase. The increases were partly due to nonspecific buffer effects associated with leaching or osmotic shock and were pH dependent. The increases were also partly due to specific enzymatic effects which appear to result from structural degradation of plant tissue, as seen in electron micrographs, leading to enhanced cell rupture and release of cytoplasmic materials. The effect of enzymatic pretreatment is thought to result in accelerated senescence by degrading major structural components which provide rigidity and mechanical strength in plant tissue. This may be primarily related to the degradation of structural polysaccharides of the cell wall and middle lamella.

Notes: Abstract Copoly (α-amino acid)s consisting ofL-glutamic acid residue andN 5-ω hydroxyalkyl-L-glutamine residue, i.e., 2-hydroxyethyl, 3-hydroxypropyl, and di-2-hydroxyethyl derivatives were prepared by the reactions of copoly (L-glutamic acid) containing succinimide ester with corresponding amino alcohols. The conformation of these copolymers was examined by the CD and infrared measurements. These three copolymers containing about 20–30% hydroxyalkyl groups undergo a methanol-induced and a pH-induced conformational transitions. The copolymer containing about 50% 3-hydroxypropyl group assumes the α-helical conformation in the pH region from 2.5 to 11.6, and in a methanol-water mixture (9∶1). On the other hand, the copolymer containing about 60% di-2-hydroxyethyl groups does not allow any helical conformation even at lower pH and also even in a trifluoroethanol-water mixture (9∶1), suggesting that the branched hydroxyalkyl group is unfavorable for the formation of α-helix. Furthermore, the poly(N 5-di-2-hydroxyethyl-L-glutamine) is shown to have a rather disordered structure in the solid state.

Notes: Summary Silica calculi in man are extremely rare; only 12 cases have been reported. In an electron microscopic study of human urinary stones, siliceous deposits were encountered in three out of 180 stones as a discrete component of stones. There were no histories of magnesium trisilicate administration in these cases. Morphology of the deposits was distinctive from any other components of the stones and bore some resemblance to animal silica calculi. Siliceous deposits in human urinary stones appear to be more common than generally recognized.

Notes: Abstract We consider exactly and strongly consistent voting functions where the alternative set is the set of real numbers and each person's preference ordering is determined by a utility function ¦x−x*¦ wherex * is his most preferred alternative. We prove that a voting function which is continuous, anonymous, weakly Pareto, and strongly and exactly consistent must coincide with a class of generalized medians studied byMoulin [1978]. Thus, such a function is actually strategyproof. The continuity assumption can be weakened a little, but we give an example of a noncontinuous function which is strongly and exactly consistent, anonymous, and weakly Pareto, but is not strategyproof.

Notes: Abstract On the basis of [1] this note examines nonlinear electromagnetic phenomena in a dense plasma brought about by the variation in its electrical conductivity as the electrical field changes. It is well known that the electrical conductivity depends on the electric field strength due to the following causes. The electrons in moving in the electric field receive energy from the field which may be considerable over the free path length. However it is difficult for this energy to be transferred to the heavy particles. In monatomic gases the energy exchange between electrons and heavy particles comes about basically as a result of elastic collisions. Thus a noticeable difference in electron and ion temperature, determined by the electron energy balance taking radiation losses into account, turns out to be possible even for relatively weak electric fields. In molecular gases, on the other hand, the fundamental energy exchange mechanism is the excitation of the rotational and oscillatory degrees of freedom of the molecules. Thus the electron energy in these gases is dissipated relatively easily, and the electron temperature is not observed to be noticeably higher than the atomic temperature. The concept of the characteristic “plasma field” Ep is introduced in [2], which is determined for an Isotropic plasma by the relation $$E_R = \sqrt {3kTme^{ - 2\delta } (\omega ^2 + v_0 ^2 )} .$$ Here k is the Boltzmann constant, T is the plasma temperature in the absence of a field, m and e are the electronic charge and mass, & is the mean fraction of energy transferred to a heavy particle by an electron on collision,ω is the frequency of field variation, ν0 is the electron-ion collision frequency in the absence of a field. In weak electromagnetic fields (E≪Ep) the plasma maintains thermodynamic equilibrium, and the electrical conductivity of the plasma is independent of the field. In strong electric fields (E≫Ep) there is a sharp difference of electron temperature and the voltage-current characteristics of the plasma become nonlinear. The question of nonequilibrium electrical conductivity has been fairly fully studied [3–5] as regards monatomic gas plasmas like argon and potassium mixtures. It was shown in [3] that for the plasmas which were considered the dependence of the electrical conductivity on the electric field with no magnetic field present could be satisfactorily described by a power function of the absolute current density, i.e., σ =c∣j∣ γ , where c is a function of the atomic temperature. This function has also been confirmed experimentally for an argon-potassium plasma for a temperature of the order of 0.2 eV and a pressure of the order of 1 atm. [3]. In the following we consider electromagnetic phenomena in a dense plasma with an electrical conductivity of the type σ =c∣j∣γ when it is in motion in a traveling magnetic field. It is assumed that the plasma parameters and limits of variation of the independent quantities (j, Te) are such that the function σ =c∣j∣γ is stable [4]. In addition the plasma is taken as having the properties of an ideal incompressible fluid. These last assumptions together with the assumption that the gradients of static pressure and pondermotive forces are only in the direction of plasma motion allow us to commence from the equations of electrodynamics.

Notes: Abstract Hall phenomena in an electrically conducting fluid with a variable magnetic field were considered in [1]. In that paper the basic characteristics of the above-mentioned phenomena are determined, with certain unimportant constraints, for the case of fluid motion along a channel of rectangular cross section in a traveling magnetic field. The magnetic Reynolds number was assumed to be small, and a solution was given for the induction field in the form of a series in powers of the indicated parameter. Quantitative estimates based on the data of [1] are impossible in the case of relatively high electrical conductivity of the fluid, although certain conclusions of a qualitative nature remain valid. There is thus reason to consider the case of high magnetic Reynolds numbers. This will also allow a fuller picture of the characteristic Hall effect phenomena to be constructed for a variable magnetic field.

Notes: Abstract A formulation is given of the problem of the stability of piston-flow motion in a traveling magnetic field. It is shown that this question reduces to the problem of stability of motion in the presence of constantly acting perturbing forces. The second Lyapunov method is used as the basis to present the sufficient criteria for stability of the flow motion with respect to certain specified quantities.