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1. The effects of temperature acclimation on electrical properties of earthworm axons (Lumbricus terrestris) were studied using intracellular stimulating and recording techniques. 2. Cold acclimation, compared to warm acclimation, was associated with decreased action potential duration and cable input resistance and increased maximum rate of rise and decline of the action potential and increased excitation threshold. In each case the direction of change occurring during acclimation to 5° C was opposite to that occurring immediately after cooling to 5° C, i.e., the acclimation changes were compensatory. 3. The significance of these changes is discussed with regard to their influence on over-all nerve function after thermal acclimation. © 1969 Springer-Verlag.

The reaction of 2,2′-bipyridylamine (abbreviated BPAH) with divalent nickel salts results in the formation of several products, the type of which depends on the metal:ligand ratio and the coordinating ability of the associated anion. Thus, tetrahedral [Ni(BPAH)Cl2] and octahedral [Ni(BPAH)3] (ClO4)2 and [Ni(BPAH)2Cl2] have been isolated and characterized. In these complexes, dipyridylamine coordinates in a bidentate manner through the two pyridine nitrogens. Deprotonation of the amine at ambient temperature in butanol results in the conversion of the paramagnetic [Ni(BPAH)2Cl2] species into a six-coordinate polymeric material of the general formula Ni(BPA)2 where the deprotonated bipyridylamine moiety (ab¬breviated BPA) is coordinating in a tridentate manner with the amine nitrogen acting as a bridge. This polymer is cleaved quite readily by the action of water, pyridine, and, presumably, other complexing solvents. Deprotonation of [Ni(BPAH)-Cl2] at high temperatures in naphthalene or reaction of the deprotonated polymer with nickel(II) chloride, also at high temperatures, yields a red crystalline trinuclear complex of the molecular formula [Ni3(BPA)4Cl2]. Deprotonation of bis(2,2′-bipyridylamine)copper(II) chloride and bis(2,2′-bipyridylamine)palladium(II) perchlorate give the expected four-coordinate square-planar product. The deprotonated complexes of palladium, copper, and nickel are compared and corre¬lations are made between their ease of formation and the geometry and electronic arrangement of the central metal ion. © 1968, American Chemical Society. All rights reserved.

Both negative and positive cultural factors affect innovative efforts in developing countries. In the case of Ethiopia, negative factors include a low esteem for craftsmanship. Even where modern education is making inroads on some negative factors, as in the towns, feudalistic attitudes toward labor and the preference for unskilled labor on the assumption that it is more economical, act to continue functionally inefficient attitudes. In contrast, positive factors exist in traditions of mutual aid, now spreading from South Ethiopian cultures northward. An excellent model for mutual aid may be found in the practices of the migrant weavers' association of the Gurage and some neighboring tribes. Ethiopia provides an interesting area for the study of human factors in developing countries since it has not passed through a colonial period. Various stages of development can be traced comparatively free of outside influences. © 1968, Human Factors and Ergonomics Society. All rights reserved.

The action of phosgene on N, N'-disubstituted ureas is described in literature as giving a variety of products depending upon the reaction conditions. However, in no instance has the formation of N, N', N''-trisubstituted guanidines been reported from the above reaction. A novel synthesis is now presented in which these aforementioned guanidines are obtained. This reaction involves the phosgenation of N, N'-dialkyl- or N-alkyl-N'-arylureas at temperatures between 110 and 120° in an inert solvent such as monochlorobenzene. In the case of symmetrically disubstituted alkylureas, the N, N', N''-trialkylguanidines in the form of their hydrochloride salts are obtained. Unsymmetrically substituted ureas upon phosgenation also give guanidines, the type of which, in terms of their substituents, is dependent upon the ability of the urea nitrogen to act as a nucleophile as well as the steric nature of the substituent itself. Thus, phosgenation of N-cyclohexyl-N'-phenylurea gives N, N'-dicyclohexyl-N''-phenylguanidine exclusively. In cases where the substituents on nitrogen atoms of the urea molecule are alike in electron-donating abilities, product distributions are obtained, as with Ncyclohexyl-N'-isopropylurea. Where one urea nitrogen is strongly deactivated, as with N-cyclohexyl-N'-trifluoroethylurea, there is no indication of guanadine formation. Different types of compounds are isolated from these reactions. A mechanism is proposed to account for these observed patterns. Copyright © 1967, American Chemical Society. All rights reserved.

A total of 243 bats belonging to six species were collected in the tropical zone of west central Colombia. Three individuals of Artibeus lituratus (2 males and 1 female) from Melgar, Colombia, harboured Paracoccidioides brasiliensis; cultures being taken directly from the intestinal tract. To our knowledge this is the first report of recovery of P. brasiliensis from animals. © 1965 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.

This paper characterizes quasi-pure projective (q.p.p.) and quasi-pure injective (q.p.i.) p-groups, and hence characterizes all such (abelian) torsion groups. A p-group is q.p.i. if and only if it is the direct sum of a divisible group and a torsion complete group. A nonreduced p-group is q.p.p. if and only if it is the direct sum of a divisible group and a bounded group; a reduced p-group is q.p.p. if and only if it is a direct sum of cyclic groups. © 1977 American Mathematical Society.

The findings in this study that self reported acceptance of self and others and interpersonal skills increased following the Workshop must themselves be regarded within the limitations of a small sample, an analysis of only one leader's group participants, measurements by ratings, and a quasi experimental design. Nevertheless, human relations training appears to be a valuable component to program more systematically into teacher education. Work in developing specific training goals and procedures relevant to personal growth as related to competence in the classroom is the next step. The fact that such a short training program could affect the way student teachers feel about themselves should encourage further research and experimentation.

Several cobalt(III) complexes of the V-hydroxyethyliminodiacetate ion (“heida”) have been prepared. Infrared and nmr studies, as well as exchange studies with D2O, show that the ligand tends to be tridentate and that the alcoholic hydroxyl group does not coordinate. Moreover, the alcoholic group in the complex can be acetylated without destruction of the complex. However, in [Co(en)(heida)]0, the alcoholic OH loses its proton, and the ligand becomes trinegative and tetradentate. © 1974, American Chemical Society. All rights reserved.

Reports an error in the original article by Mark B. Fineman (Journal of Experimental Psychology, 1971[Oct], 90[2]], 215-221). Fig. 1 and Fig. 2 on pp. 216 and 217 were shown inverted. This mistake made it appear that Stimulus 1 was Stimulus 2, and that Stimulus 3 was Stimulus 4, and that the four stimuli were upside down. (The following abstract of this article originally appeared in record.) Proposed that the cue of relative size may facilitate depth perception in accordance with a crossed or uncrossed disparity in stereograms in which both tendencies are equally represented. A concurrent concept was that the latency associated with the perception of depth in random-dot stereograms may be due, in part, to a cue conflict between binocular disparity and relative size. 4 male and 2 female graduate students were given 8 presentations of 5 stereographic stimuli, in which disparity was ambiguous but relative size was systematically altered. Ss were tested for direction of depth preferences and response latency. Both the relative-size effects and an uncrossed disparity bias were evidenced in the data. The latter effect was attributed to binocular rivalry between dissimilar elements in the stereoscopic half-fields. It is concluded that depth cue relationships are more complex than had been suggested by simple dominance theories. (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1972 American Psychological Association.