Showing papers by "University of California, Santa Cruz published in 1971"

Simple LR(k) grammars

Abstract: A class of context-free grammars, called the “Simple LR(k)” or SLR(k) grammars is defined. This class has been shown to include weak precedence and simple precedence grammars as proper subsets. How to construct parsers for the SLR(k) grammars is also shown. These parser-construction techniques are extendible to cover all of the LR(k) grammars of Knuth; they have been implemented and by direct comparison proved to be superior to precedence techniques, not only in the range of grammars covered, but also in the speed of parser construction and in the size and speed of the resulting parsers.

Interstellar molecules and dense clouds.

Abstract: Current knowledge of the interstellar medium is discussed on the basis of recent published studies. The subjects considered include optical identification of interstellar molecules, radio molecular lines, interstellar clouds, isotopic abundances, formation and disappearance of interstellar molecules, and interstellar probing techniques. Diagrams are plotted for the distribution of galactic sources exhibiting molecular lines, for hydrogen molecule, hydrogen atom and electron abundances due to ionization, for the densities, velocities and temperature of NH3 in the direction of Sagitarius B2, for the lower rotational energy levels of H2CO, and for temporal spectral variations in masing H2O clouds of the radio source W49. Future applications of the maser and of molecular microscopy in this field are visualized.

DDT in California Sea Lions

Abstract: WE wish to report extraordinary concentrations of DDT residues* in California sea lions, Zalophus californianus, which inhabit year round the coastal waters of California and Baja California, Mexico1. These waters receive agricultural runoff from California valleys where DDT has been used extensively2–4, and where residues have been increasing in the primary stages of some coastal pelagic food chains5.

Isolation of microbodies from plant tissues

Abstract: Specialized microbodies have previously been isolated and characterized from fatty seedling tissues (glyoxysomes) and leaves (leaf peroxisomes). We have now examined 11 other plant tissues, including tubers, fruits, roots, shoots, and petals, and find that all contain particulate catalase, a distinctive common enzyme component of microbodies. On linear sucrose gradients the catalase activity peaks sharply at a higher equilibrium density (1.20 to 1.25 gram per cm(3) in the various tissues) than the mitochondria (1.17 to 1.20). Only small amounts of protein are recovered in the fractions containing catalase, although a definite band is visible in preparations from some tissues, e.g., potato. As in the preparations from castor bean endosperm and spinach leaves for which comparable data are provided, the distribution of glycolate oxidase and uricase follows closely that of catalase on the gradients. The preparations from potato lack glyoxylate reductase and the transaminases, typical enzymes of leaf peroxisomes, and the distinctive enzymes of glyoxysomes are missing. Nonspecialized microbodies with limited enzyme composition can thus be isolated from a variety of plant tissues.

Uricase and allantoinase in glyoxysomes.

Abstract: In fat-degrading tissues of seedlings of seven different plant species examined, uricase activity (urate:O(2) oxidoreductase, EC 1.7.33) was associated with particulate fractions. After equilibrium density centrifugation on sucrose density gradients the enzyme activity was recovered in the glyoxysomal band (density: 1.25 grams per cubic centimeter). Allantoinase is also present in glyoxysomes but, equally, in the proplastid region (density: 1.22 grams per cubic centimeter). Xanthine oxidase, xanthine dehydrogenase, allantoicase, and urease were not detected in glyoxysomes from castor bean endosperm. Uricase in these particles shows its maximal activity at pH 8.9. The apparent K(m) is 7.4 mum. Urate concentrations greater than 120 mum as well as certain other purine compounds inhibit the enzyme. Cyanide at a concentration of 10 mum is a potent inhibitor. 2,6-Dichlorophenolindophenol did not substitute for oxygen as electron acceptor.

Behavioral choice and habituation in the marine mollusk Pleurobranchaea californica MacFarland (Gastropoda, Opisthobranchia)

Abstract: 1. Complex behavior in the carnivorous marine gastropod Pleurobranchaea californica is described (Figs. 1–6). 2. Situations requiring behavioral choice can be created by simultaneously delivering the stimuli for two different behavior patterns. In such situations feeding is elicited in preference to other behaviors, including sexual activity and righting responses. 3. Two behaviors have been examined in detail, the withdrawal response to light and feeding. The withdrawal response habituates; correlated studies on the nervous system showed that the habituation has two causes, adaptation of the visual response (Figs. 8, 9) and habituation of the participating central pathways (Figs. 10–12). The central habituation is specific to pathways involving the visual input. Neuromuscular adaptation is not involved in the behavioral habituation. 4. The sequence of muscular activity causing the rhythmic feeding movements was determined by cinematography (Fig. 14) as well as anatomical (Fig. 15) and electromyographic (Figs. 16, 17) methods. Central nerve cells were located which either excite or inhibit efferent outflow to the feeding apparatus (Figs. 21, 22).

Induction of coleoptile elongation by carbon dioxide.

Abstract: The ability of CO(2) to induce elongation of Avena sativa coleoptile segments was examined with the use of a high resolution growth-recording device. CO(2)-saturated water causes an 8- to 16-fold promotion in the rate of elongation within 1 minute. This elongation is insensitive to a variety of metabolic inhibitors that suppress auxin-induced elongation, and the CO(2) effect cannot be prevented by pretreatment with these inhibitors. Buffers of pH 3 to 4 also stimulate elongation quickly, and it seems that at least a major part of the action of CO(2) depends upon its ability to reduce pH. The rate of elongation of auxin-promoted segments can be further enhanced by treatment with CO(2) but not vice versa.The response to CO(2) can be inhibited by mannitol at osmotic concentrations that inhibit normal growth, by calcium, and by brief pretreatment with heavy water (D(2)O). The elongation rate that results from CO(2) treatment is sensitive to temperature, but the induction by CO(2) itself appears to be almost temperature-independent.Elongation following treatment with CO(2) may be a physical flow phenomenon, essentially independent of immediate biochemical participation, which occurs when wall polymer interactions that normally restrict strain in the cell wall are weakened or broken by CO(2) in a manner that in effect substitutes for the role of metabolism in normal auxin-inducible cell enlargement.

In vitro Repression of RNA Synthesis by Purified λ Phage Repressor

Abstract: The λ repressor binds to two operator sites on λ DNA, and it is shown here that in vitro this binding blocks transcription at a very early step.

On the Mechanism of the Glitches in the Crab Nebula Pulsar

Abstract: New observations of the wisps in the Crab Nebula show further examples of activity connected with sudden changes in the rotation rate of the pulsar. The evidence leads to a model of the “glitches” in which plasma is released explosively from the closed magneto-sphere of the neutron star.

The mechanism of apical dominance in Coleus

Abstract: The development of lateral buds in isolated stems of Coleus blumei is inhibited by low concentrations of indoleacetic acid or other auxins, just as in other plants. The inhibition can be fully reversed by kinetin, about 3 times as much kinetin as IAA being needed. However, the outgrowth of the same lateral buds on intact Coleus plants is sensitive to environmental conditions, well-nourished plants in full daylight often showing little inhibition by applied auxin. It is shown that (a) the solvent used for IAA, (b) the light intensity and (c) the nitrogen and phosphorus nutrition, all control the sensitivity of the buds to auxin inhibition. Using water instead of lanolin, lowering the light intensity or decreasing the supply of either nitrogen or phosphorus all increase the degree of apical dominance.

The maximum principle for multiple-valued analytic functions

Abstract: If P is a single-valued analytic function satisfying [F(z)[ ~< 1 throughout a domain in the Riemann sphere, then of course I F(~)l ~< 1 for any particular ~. We have I F(~)I = 1 only if F is a constant of absolute value one. The same statements hold even if F is not necessarily single-valued but has single-valued absolute value, for log I FI is still subharmonic. In particular if F is not single-valued then

Influence of Cycloheximide on the Synthesis and Utilization of Amino Acids in Suspension Cultures

Abstract: Cells from 4-days old suspension cultures of Paul's Scarlet rose were incubated with acetate-U-(14)C for 10 minutes. After washing, cells were incubated for 2 hours in growth medium in the presence and absence of cycloheximide. The (14)C content of individual amino acids in the soluble form and in protein were determined at the end of the 10 minute pulse and at intervals thereafter in control cells and those treated with cycloheximide. During the period following the pulse there was a 3-fold increase in the (14)C content of protein in control cells; no such increase occurred in the presence of cycloheximide.In the control cells there was a net increase in the (14)C content of eight individual amino acids during this period. For six of these, the corresponding increases in the presence of cycloheximide were curtailed by the following amounts: arginine 98%, lysine 94%, isoleucine 93%, threonine 82%, valine 49%, and proline 36%. This is interpreted to mean that the synthesis of each of these amino acids was slowed down when their incorporation into protein was prevented.

Political participation as a function of internal-external locus of control.

Abstract: The aim was to determine whether a person's political participation is a function of his “locus of control.” Ss completed Rotter's I-E scale (1966), a political activity scale, and a self-rating of political activity. Political participation was positively correlated with internal locus of control.

Molecular Aspects of Genetic Recombination

Abstract: Publisher Summary This chapter reviews that recombination is synonymous with genetic analysis. It has been implicated in ensuring the accuracy of chromosome segregation during meiosis, as a device to circularize bacteriophage chromosomes as a prelude to their replication, in the initiation of the state of molecular parasitism for temperate phages that intercalate their DNA molecules into those of the host, and as a mechanism for the generation of genetic variability, the raw material for natural selection. It discusses that the basic mechanisms of recombination are as evolutionarily conservative as recombination is ubiquitous in nature and thus one can validly inquire into these mechanisms by considering their manifestations wherever and in whatever form they are revealed. The chapter also reviews that there could be two kinds of molecular interaction leading to recombination. One, a minimal interaction, wherein a single-stranded fragment derived from a donor molecule is intercalated into the continuity of a recipient DNA molecule. The exemplar for this interaction is seen in bacterial transformation. The other interaction, the maximal interaction, is one in which the interaction is consummated with the formation of one or two recombinant molecules of joint parentage. This kind of interaction is represented by the nonreciprocal crossing-over that occurs in phage crosses and by classical reciprocal crossing-over as seen in the eucaryotes.

The Sleep-Wakefulness Cycle in Mexican Adults

Abstract: The sleep-wakefulness patterns of 257 Mexican males and females ranging in age from the 20s to 80s was studied using a questionnaire. The average duration of sleep exceeded that typically prescribed for other Western cultures (8 hours per 24), and significantly varied with age decreasing from the 20s to 50s, after which there was an increase. There was a significantly greater incidence of sleep disturbance in subjects over 50 Compared to the other Ss the post-awakening mood of those with sleep disturbance and those over 50 was described by a significantly greater frequency of negative affect. Significant age and sex differences were found for the frequency of dream recall. The duration and frequency of daytime naps in Ss of all age groups revealed the presence of a polycyclic sleep-wakefulness cycle which has not been reported with such generality in other Western cultures.

Nappe Formation in Part of the Southern Appalachian Piedmont

Abstract: Structural studies of rocks along the Carolina slate belt – Charlotte belt boundary reveal two generations of folding, the earlier of which is represented by a large-scale antiformal nappe. As shown by field relations and quantitative analysis of the fold geometry, this early folding began prior to metamorphism, the mechanism being largely buckling. With the onset of metamorphism and cleavage-forming process, new folds were formed and the pre-existing buckle folds were modified by compressive strain. During this time, a metamorphic gradient developed along the boundary of the two belts; as the rocks became more ductile, the large antiformal nappe was emplaced in the Charlotte belt, with its root located close to the boundary between the belts. Sillimanite-grade metamorphism in the Charlotte belt outlasted the early deformation, and some upwelling of material in this hot zone may have gently arched the nappe. Late, post-metamorphism deformation produced two sets of folds with different orientation, which appear to have a conjugate relationship, and which probably formed contemporaneously. The relation between the Charlotte and Carolina slate belts may be analogous to the infrastructure/superstructure relation commonly found in other intensely deformed mountain belts of the world.

Delayed fluorescence from chlorella pyrenoidosa: effect of background illumination*

Abstract: — –With background illumination the delayed fluorescence intensity from Chlorella pyrenoidosa observed at 1 msec following a flash of light is greatly increased. It is shown that the background illumination makes a photosystem II product that increases the delayed fluorescence yield and decays in the dark with second order kinetics. The delayed fluorescence observed at 1 msec appears to be more closely related to the primary energy conversion act than delayed fluorescence observed at longer times which is more indicative of electron transport chemical activity.

Increased accuracy of binocular depth perception following REM sleep periods.

Abstract: It has been proposed that REM sleep maintains facilitation of coordinated eye movements necessary for accurate binocular depth perception (Berger, 1969) This experiment confirmed the prediction that binocular depth perception would be more accurate at the ends of REM periods than at their onsets Eight male subjects were studied during 4 non-consecutive nights of sleep Accuracy of binocular and monocular depth perception were measured with different apparatus in the evening prior to sleep onset, after awakenings made alternately at the onsets or ends of REM periods, and 15 min after awakening in the morning Accuracy of binocular depth perception was significantly better at the ends of REM periods than at their onsets (p < 001), whereas accuracy of monocular depth perception did not significantly differ That the monocular task was sensitive to variables of sleep was indicated by impairment at the first REM onset with little variation throughout the night, so that it was significantly worse 15 min after morning awakening than the previous evening (p < 05) In contrast, accuracy of binocular depth perception was significantly better in the morning than the previous evening and at REM onsets (p < 05)

Busirane and the War Between the Sexes An Interpretation of The Faerie Queene III. xi–xii

Abstract: HE masculine mindwounded first by desire and then by jealousy and envy: this is the center of the emotional and psychological experience visualized by Spenser as Busirane’s house and depicted in the concluding two cantos of Book m of The Faerie Qtleene. I shall discuss the episode in the light of the general approach to Spenser‘s poetry and the particular reading of Books rn and IV which I have partially sketchcd out in previously published essays.* Britomart, the heroine of Books III-v, visits three rooms in the castle of the enchanter Busirane: in the outermost she fmds Ovidian tapestrics displaying Cupid’s triumphs over the gods, and a gold icon of a blindfolded Cupid standing on a blinded dragon and grasping arrows “which he shot at randon” (111.xi.48.3). The walls of the middle room are decorated with “monstrous formes” (xi.51.7) of false love in gold bas-relief and with the spoils of “mighty Conquerours and Captaines strong” (xi.52.3) who were driven by ‘‘cruel1 love” (xi.p.5) to commit suicide. In this room she

The effect of strychnine administration during development on adult maze learning in the rat. II. Drug administration from day 51 to 70.

Abstract: Strychnine sulphate administered to rats during development from day 51 to day 70 affected the rate of maze learning in adulthood. Rats given the drug in a rich environment learned the maze at a faster rate and with fewer errors than rats treated with the same drug but raised in small laboratory cages. The performance of rats given no drug was intermediate to that of the drug-rich and drug-caged groups.