Showing papers by "University of California, Santa Barbara published in 1978"
TL;DR: The commonly observed high diversity of trees in tropical rain forests and corals on tropical reefs is a nonequilibrium state which, if not disturbed further, will progress toward a low-diversity equilibrium community as mentioned in this paper.
Abstract: The commonly observed high diversity of trees in tropical rain forests and corals on tropical reefs is a nonequilibrium state which, if not disturbed further, will progress toward a low-diversity equilibrium community. This may not happen if gradual changes in climate favor different species. If equilibrium is reached, a lesser degree of diversity may be sustained by niche diversification or by a compensatory mortality that favors inferior competitors. However, tropical forests and reefs are subject to severe disturbances often enough that equilibrium may never be attained.
7,795 citations
TL;DR: In this paper, the authors present an analysis of conversations between men and women in their homes, focusing on how verbal interaction helps to construct and maintain the hierarchical relations between women and men.
Abstract: The oppression of women in society is an issue of growing concern, both in academic fields and everyday life. Despite research on the historical and economic basis of women’s position, we know little about how hierarchy is routinely established and maintained. This chapter attempts to direct attention to the reality of power in daily experience. It is an analysis of conversations between men and women in their homes. The chapter focuses on how verbal interaction helps to construct and maintain the hierarchical relations between women and men.
732 citations
TL;DR: It is concluded that the microtubule assembly-disassembly "equilibrium" is a steady state summation of two different reactions which occur at opposite ends of the micro Tubule, and that assembly and disassembly occur predominantly and perhaps exclusively at the opposite ends under steady state conditions in vitro.
555 citations
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01 Jan 1978TL;DR: Darboux functions as discussed by the authors are in the first class of Baire Continuity and approximate continuity of derivatives The extreme derivatives of a function Reconstruction of the primitive The Zahorski classes The problem of characterizing derivatives Derivatives a.i.d.
Abstract: Darboux functions Darboux functions in the first class of Baire Continuity and approximate continuity of derivatives The extreme derivatives of a function Reconstruction of the primitive The Zahorski classes The problem of characterizing derivatives Derivatives a.e. and generalizations Transformations via homeomorphisms Generalized derivatives Monotonicity Stationary and determining sets Behavior of typical continuous functions Miscellaneous topics Recent developments Bibliography Supplementary bibliography Terminology index Notational index.
357 citations
280 citations
TL;DR: In this paper, the authors used the Kolmogorov-Smirnov goodness-of-fit test and one-way analysis of variance to find that approximately 70% of the variability in the spacing of pools can be explained by the variability of channel width.
Abstract: Quantitative analysis of the spacing of pools in bedrock and alluvial stream channels in California, Indiana, Virginia, and North Carolina suggest that the tendency for streams to meander in the vertical (or third) dimension, as in the horizontal plane, is a fundamental characteristic of many streams that is independent of material type. Simple linear-regression and correlation models reveal that approximately 70% of the variability of the spacing of pools can be explained by the variability of channel width. Analysis of the spacing of 251 pools in eleven streams, utilizing the Kolmogorov-Smirnov goodness of fit test and one-way analysis of variance suggests that the hypothesis that the data from bedrock and alluvial channels are from the same population cannot be rejected at the 0.05 level of significance.
Morphologic maps and field observations of stream channels incised in sandstone, limestone, metavolcanic rock, and syenite suggest that although these streams have much in common with alluvial stream channels, there exist considerable differences in certain aspects of channel morphology. This results because bedrock control of morphology locally may be more significant than the effects of general processes that tend to produce rhythmic channel forms such as pools and riffles. However, local controls tend to mask rather than destroy the effects of more general processes that produce the third dimension of meandering streams.
278 citations
TL;DR: In this paper, the authors investigated the possible contributions of tidal heating to the thermal history of the Earth-Moon separation, and showed that the contribution of a two-layer Moon with a soft core and rigid mantle is negligible.
233 citations
TL;DR: The ease with which the bacterial cell can achieve functional high-level gene expression from cloned yeast DNA indicates that there are no significant barriers preventing expression of many yeast genes in E. coli.
230 citations
TL;DR: It is proposed that two events, poleward-sliding of anti-parallel microtubules and an opposite end assembly/disassembly of all microtubles, occur constantly throughout mitosis and act coordinately to produce mitotic movement.
Abstract: THE molecular mechanism of mitosis in higher eukaryotic cells is largely unknown. Here, we state briefly some aspects of the mitotic mechanism that are well characterised, add information derived from our recent investigations, and offer a new model of mitotic movement based on intrinsic microtubule behaviour. We propose that two events, poleward-sliding of anti-parallel microtubules and an opposite end assembly/disassembly of all microtubules, occur constantly throughout mitosis and act coordinately to produce mitotic movement.
222 citations
TL;DR: In this article, low energy electron diffraction patterns were obtained for Pt(100), Pt(111), and polycrystalline electrodes before and after exposure to aqueous 1 M H 2 SO 4.
207 citations
TL;DR: The study as a whole suggests the importance of obtaining multiple measures of the effects of parent and teacher training programs, including measures of acquisition and generalization of both adult and child behaviors.
Abstract: Two experiments were conducted to assess the generalized effects of several different parent/teacher training programs. In Experiment I it was found that a brief demonstration of how to teach an autistic child new behaviors was sufficient to teach parents how to teach those children those behaviors. However, generalization to new child-target behaviors did not take place. Another parent training program, which did not demonstrate how to teach any one specific child behavior, but was based on teaching the use of general behavior-modification procedures, was effective in teaching the parents how to teach new child-target behaviors. Experiment II then provided analyses of the individual effects of several components of the generalized training program. The results showed that videotape illustrations of the procedures, without the presence of a master teacher, were sufficient to teach the adults. However, sub-parts of the videotapes produced highly specific training results, with each component changing corresponding areas of the adults' behaviors. Viewing of the entire package was necessary before the adults were able to improve the autistic children's behaviors. The study as a whole suggests the importance of obtaining multiple measures of the effects of parent and teacher training programs, including measures of acquisition and generalization of both adult and child behaviors.
TL;DR: The gametophytes of 9 laminarian species became fertile in the unicellular stage or in a few-celled stage, when appropriate temperatures and a sufficiently high quantum irradiance in the blue part of the spectrum were supplied.
Abstract: The gametophytes of 9 laminarian species (4 from southern California, and 5 from central California, USA) became fertile in the unicellular stage (female gametophytes) or in a few-celled stage (male gametophytes), when appropriate temperatures and a sufficiently high quantum irradiance in the blue part of the spectrum were supplied. Vegetative growth, leading to the formation of filamentous gametophytes was light-saturated at relatively low irradiances (4 W m-2; equivalent to about 2 nE cm-2 sec-1 or an illuminance of 1000 lux), whereas 2 to 3 times this irradiance in continuous fluorescent cool white light was needed to induce the majority of the gametophytes to become fertile. An illuminance of 8300 lux did not inhibit the development of the gametophytes from southern Californian species. Egregia menziesii exhibited an exceptionally low quantum demand for induction of fertility. Gametophytes of species from central and southern California differed in regard to their temperature optimum for growth (12°C in the former, 17°C in the latter) and their upper temperature limit for reproduction (17°C in the former, 20°C in the latter).
TL;DR: In this paper, the authors used a mixture of Newtonian and non-Newtonian fluids to model the flow in a subduction zone which is viscously driven by the motions of the converging plates and the descending slab.
Abstract: Corner flows of Newtonian and non-Newtonian fluids are used to model the flow in a subduction zone which is viscously driven by the motions of the converging plates and the descending slab. The pressures induced by the flow tend to lift the slab up beneath the overriding plate thereby offsetting the tendency of gravity to align the slab with the vertical. The low angles of subduction observed in Peru and Central Chile may be the result of strong dynamic pressures forcing the slab up against the overriding plate. Viscous coupling between the overriding plate and the downgoing slab is essential if the nonvertical dips of slabs are a consequence of the balance between gravitational and pressure torques. For a Newtonian mantle, shear stresses and pressures on the top of the slab are comparable. If the mantle is non-Newtonian, however, the pressures greatly exceed the shear stresses, for most acute dip angles. Thus frictional forces on the top and bottom surfaces of slabs are less important in resisting slab descent into a non-Newtonian mantle than they are in resisting penetration into a Newtonian mantle.
TL;DR: In this article, a quantized field in a Bianchi type-I anisotropic expanding universe is considered, and boundary conditions are imposed at an initial time t/sub 0/ of the order of the Planck time with the initial expansion rates varying over a wide range consistent with the constraints.
Abstract: We consider a quantized field in a Bianchi type-I anisotropically expanding universe. A suitable expectation value of the renormalized energy-momentum tensor acts as the source of the metric in the Einstein equations. The coupled set of differential equations is numerically integrated, with the help of several approximations, in the case when the quantized field is the massless conformal scalar field. Boundary conditions are imposed at an initial time t/sub 0/ of the order of the Planck time, with the initial expansion rates varying over a wide range consistent with the constraints. It is found that the expansion rates tend toward isotropy and approach a radiation-filled Friedman expansion in an interval of less than 10/sup 3/ Planck times, for the full range of initial expansion rates considered.
TL;DR: In this article, the authors presented a simple model to calculate the charge exchange probability for ions scattering from solid surfaces, including interactions with both broad band delocalized electrons and with localized core electrons within an Anderson type Hamiltonian with time dependent parameters.
TL;DR: U-Pb measurements on sphene, apatite, and feldspar from the plutons, along with previously published K-Ar and fission track ages shed light on the post-emplacement thermal histories of the Plutons as discussed by the authors.
Abstract: U-Pb isotopic measurements on zircons from some granitic rocks of the Salinian block indicate emplacement and crystallization of these rocks about 104 m.y. ago (mid-Cretaceous). The relatively radiogenic nature of initial Sr and common Pb in these rocks, and the presence of an inherited component of zircon in some of them strongly suggest the involvement of continental crust in the genesis of the magmas. Possibly the magmas were generated in a zone of melting that overlapped the boundary between the mantle and the continental crust. U-Pb measurements on sphene, apatite, and feldspar from the plutons, along with previously published K-Ar and fission-track ages shed light on the post-emplacement thermal histories of the plutons. Most of the samples from the northern part of the Salinian block (Bodega Head, Point Reyes) show relatively simple thermal histories. Evidently these plutons were emplaced at moderate levels in the crust, crystallized, and cooled to moderate temperatures over an interval of about 10–15 m.y. Plutons from the central Salinian block (Santa Lucia Range) show more complex and prolonged thermal histories. These plutons evidently were emplaced at greater depths in the crust than were the plutons from the northern Salinian block. They remained at elevated temperatures for ca. 25 m.y., then cooled fairly rapidly, probably as a result of rapid uplift and erosion. One sample from the northern Salinian block shows an even longer span of time between emplacement and cooling. The thermal evolution of the Salinian plutonic rocks predates major offset along the San Andreas fault zone and thus reflects the thermal evolution of the undisrupted source terrane of the Salinian block. Isotopic measurements of the type reported here might therefore prove valuable in correlations across the San Andreas fault zone. Moreover, detailed study of thermal evolution within the Salinian block could shed light on major offsets within the block.
TL;DR: In this paper, the authors considered the problem of placing bounds on the mass and moment of inertia of non-rotating neutron stars assuming that the properties of the constituent matter are known below a fiducial density ϱ 0 while restricted only by minimal general assumptions above this density.
TL;DR: In this paper, it was shown that these special subnormal operators as well as certain other operators do in fact have nontrivial invariant subspaces, and it was then shown that they can be used to prove the existence of subnormal subnormals.
Abstract: A theorem of D.E. Sarason is used to show that all subnormal operators have nontrivial invariant subspaces if some very special subnormal operators have them. It is then shown that these special subnormal operators as well as certain other operators do in fact have nontrivial invariant subspaces.
TL;DR: These devices have proved effective for the recovery of living animals from depths as great as 2500 m and have been described.
TL;DR: In this paper, the frequency-dependent dipole moment and the radiation emission spectrum for a small particle located above a metal film were calculated and a resonance structure associated with a localized surface plasma mode at a frequency corresponding to the peak in the structure observed in the emission spectra.
Abstract: A resonancelike structure has been reported in the frequency spectrum of light emitted from small-particle tunnel junctions. Here we present a calculation of the frequency-dependent dipole moment and the radiation emission spectrum for a small particle located above a metal film. The dipole moment exhibits a resonance structure associated with a localized surface plasma mode at a frequency corresponding to the peak in the structure observed in the emission spectra.
TL;DR: A controlled field experiment is designed to evaluate the effects of intra- and interspecific interactions affecting two distinct horizontal patterns, thereby providing a test of current plant distribution theory.
Abstract: THE accurate description of horizontal patterns of distribution and the determination of the mechanisms resulting in these patterns1,2 are primary objectives of plant ecology. Although there have been many studies of horizontal patterns, most investigations have not proceeded beyond the initial stage of detection and analysis of pattern, leaving suggestions of causation untested. Controlled field experiments that test mechanisms which may regulate distributions are rare3. We have designed a controlled field experiment to evaluate the effects of intra- and interspecific interactions affecting two distinct horizontal patterns, thereby providing a test of current plant distribution theory.
TL;DR: In this article, the authors examined the maximum solar energy available to an Earth-surface collector as a function of latitude, the north-south tilt of the collector from the Earth's surface (θ), and whether the collector is an ideal tracker (follows the Sun both north-South and east-West), an east-west tracker, or a fixed type.
TL;DR: In subsurface samples of Wilcox (Eocene) sandstones, calcite cements occur above 2315 m depths, whereas ankerites occur at depths from 2560 m to at least 4650 m as discussed by the authors.
Abstract: In subsurface samples of Wilcox (Eocene) sandstones, calcite cements occur above 2315 m depths, whereas ankerites occur at depths from 2560 m (temperatures 125 ° C) to at least 4650 m (temperatures 210 ° C). Microprobe analyses indicate that some shallow ankerites have appreciable excess calcium, analogous to protodomites. Ankerites at depths greater than 3200 m have compositions of about CaMg0.5Fe0.5(CO3)2.
TL;DR: The Papoose Flat pluton as mentioned in this paper is composed of quartz monzonite with K-feldspar megacrysts and crops out as an elongated east-trending dome, 16 km long and 8 km wide.
Abstract: The Papoose Flat pluton (75 to 81 m.y. old) is one of several Mesozoic granitic bodies in the White-Inyo Range which are regarded as satellites of the Sierra Nevada batholith. The pluton, composed chiefly of quartz monzonite with K-feldspar megacrysts, crops out as an elongated east-trending dome, 16 km long and 8 km wide. It was emplaced within the southwest limb of the major southeast-plunging Inyo anticline, consisting of virtually unmetamorphosed late Precambrian and Cambrian sedimentary rocks. Stratigraphic units around the western half of the pluton have a regionally metamorphosed aspect and are tectonically and concordantly thinned to as little as 10% of their regional thicknesses without loss of Stratigraphic identity or continuity. Around the discordant eastern contact, however, wall-rock textures are hornfelsic, and there is little or no attenuation of the stratigraphic succession. Foliation, lineation, and preferred orientation of minerals are well developed in the western half of the pluton and its wall rocks and, together with the boudinaged wall rocks, are consistent with the geometry of strain required for attenuation of the stratigraphic succession. The structural evidence indicates that the granite penetrated discordantly through lower formations in the anticline and formed a “blister” in the fold limb beneath the stretched higher formations. Metamorphic mineral assemblages of the wall rocks suggest a maximum temperature of metamorphism of less than 600 °C and a pressure of less than 2.5 kb.
01 Jun 1978-Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology
TL;DR: This study examines both the avoiding reactions and velocities of normal and mutant paramecia in attractants and repellents and shows that the animals accumulate or disperse either by changing the frequency of avoiding reactions or by changing swimming velocity.
Abstract: Paramecia show chemotaxis, that is, they accumulate in or disperse from the vicinity of chemicals. This study examines both the avoiding reactions (abrupt random changes of swimming direction) and velocities of normal and mutant paramecia in attractants and repellents and shows that the animals accumulate or disperse either by changing the frequency of avoiding reactions or by changing swimming velocity. Mutations or conditions that eliminate avoiding reactions abolish the chemotaxis response to chemicals that cause accumulation or dispersal by modulation of frequency of avoiding reactions but not the response to chemicals that cause chemotaxis by modulation of velocity. The current knowledge of the bioelectric control of the swimming behavior inParamecium and observations of mutants defective in bioelectric control and in chemotaxis are used to develop a hypothesis for membrane potential control of chemotaxis: attractants that require the avoiding reaction slightly hyperpolarize the membrane; repellents that require the avoiding reaction slightly depolarize the membrane; repellents that cause chemitaxis by modulation of velocity strongly hyperpolarize the membrane.
TL;DR: It was shown that competition for soil moisture, light, and nutrients could not account for the lack of herbs in bracken stands, and uniformity of soil pH, texture, water-holding capacity, and organic matter content ruled out variability in physical factors as a cause.
Abstract: Bracken,Pteridium aquilinum, exerts a strong dominance over associated plants throughout much of its worldwide range. Associated plants are often severely inhibited or even excluded from dense stands of the fern. This study investigated the various aspects of herb suppression in bracken stands and assessed the contribution of the various forms of interference between plants to the establishment and maintenance of bracken dominance. It was shown that competition for soil moisture, light, and nutrients could not account for the lack of herbs in bracken stands. Further, uniformity of soil pH, texture, water-holding capacity, and organic matter content ruled out variability in physical factors as a cause. Baiting and trapping experiments showed that the higher concentration of animal activity inside the bracken stands contributed significantly to the pattern of herb suppression, but only against select species. The maintenance of this pattern in the animal-free Santa Cruz Island stands indicates the importance of another factor, allelopathy. It was found that phytotoxins leached from the dead, standing bracken fronds with the first few rains of the wet season were largely responsible for herb suppression. These toxins were isolated in raindrip and from soil inside the fern stands. Removal of the fronds from the stand before the rains could leach them resulted in reinvasion by the herbs after several seasons, and, conversely, placing fronds over the herbs in the grassland brought about herb inhibition. A number of known allelopathic chemicals were tentatively identified from bracken leachates. The importance of the interaction of allelopathy with other factors of plant interference is illustrated by bracken.
TL;DR: In this paper, a method is presented which can successfully isolate components of remanent magnetization having intermediate relative stability in a single rock sample which contains any number of remanence components with overlapping coercivity or blocking temperature spectra.
TL;DR: Cyclic voltammetry and differential pulsevoltammetry at graphite paste electrodes are evaluated for their ability to detect the chemical neurotransmitter, dopamine, and its major metabolites, homovanillic acid and 3-methoxytyramine, in mammalian brain.
TL;DR: Preliminary results suggest that basal levels are considerably lower and the latency to corticosteroid stress response is shorter than previously reported.