bluuebunny/crossref_metadata_2025 huggingface dataset:
Habima's The Golem
Authors: Citron Atay
Published: April 2006

After The Dybbuk, The Golem was Habima's most acclaimed production. It opened on March 15, 1925, when Habima was still a studio of the Moscow Art Theatre, and since then it has run for 340 performances on three continents. In 1926, the company toured Europe and the United States, performing The Golem with two other plays. When the company visited Palestine in 1928, the play was revived, and later, in 1948, it was staged in America again. In New York, it was chosen—on the basis of box office demand—as an extra bill for the final week of Habima's season at the Broadway Theatre. In 1954, The Golem represented Israel in the First International Theatre Festival in Paris.

The production excelled in its acting, being a perfect example of the unique expressionistic style that made the Habima players so famous in The Dybbuk.
The Jewish Theatre Festival 1980
Authors: Margolis Tina , Weinacht Susan , Frick John
Published: April 2006

During the mid-1970s the impetus for founding a Jewish Theatre Association stemmed from the energy and commitment of two individuals. Although living over a thousand miles apart and of different professional backgrounds, Norman Fedder and Steve Reisner each simultaneously began exploring his Jewish heritage through theatre. Increasingly fascinated and moved by these experiences, each felt the need to form a theatre organization specifically devoted to the Jewish experience.

In 1972, Norman Fedder, the head of the Playwrights Workshop at Kansas State University, directed a student's play based on the life of Jeremiah. As Fedder recalls, the discussion with the audience which followed “was one of the most exciting experiences I ever had in the theatre.” As a result of this performance, Fedder, a dramatist with many community productions to his credit, was commissioned to write and direct other works with religious themes for several churches and synagogues.
Engel’s Ideas for a Theory of Acting
Authors: Veltrusky Jarmila
Published: April 2006

Among the multitude of writings about actors and acting which appeared in the 18th century all over Europe, Johann Jacob Engel's Ideen zu einer Mimik (1785-1786) merits special attention, at once as a pioneering attempt at a semiotics of acting and as a valuable source of information about the actual practice of contemporary actors and actresses. It takes the form of 44 letters (numbers 1-27 making up Volume I, numbers 28-44 Volume II). Despite its easy and apparently casual style, it is in fact a quite systematic analysis, even if it repeatedly disclaims the ambition to be exhaustive. It is difficult to account for the long neglect the work has suffered. When it first appeared, its importance was evidently recognized, since it was promptly translated into other languages, but it seems to have been soon forgotten.
Old‐Growth Pseudotsuga menziesii Communities of a Western Oregon Watershed: Biomass Distribution and Production Budgets
Authors: Grier Charles C. , Logan Robert S.
Published: April 2006

Living biomass, organic matter distribution, and organic matter production budgets were determined for plant communities of a small watershed dominated by 450—yr—old Pseudotsuga menziesii (Mirb.) Franco forests. Dominant trees in the communities were large, up to 175 cm diam and 80 m tall. Aboveground tree biomass of the various communities ranged from 491.8—975.8 tonnes/hectare, total aboveground living biomass ranged from 500.4—982.5 t/ha, total leaf biomass ranged from 10.4—16.3 t/ha and total organic matter accumulations ranged from 1,008.3—1,513.7 t/ha. Total tree biomass in the various communities was more related to past mortality than habitat differences. Biomass of standing dead trees and fallen logs was generally inversely related to aboveground tree biomass. Amounts of woody detritus were large, ranging from 59.0—650.6 t/ha or 4.3%—43.0% of total community organic accumulation. Aboveground tree biomass increment was negative in all communities, ranging from —2.9 to —6.2 t/ha. Positive increment by shrubs and trees <15 cm dbh, produced overall aboveground biomass increment —2.5 to —5.0 t/ha. Mortality averaged 1% of standing biomass. Aboveground net primary production in the various communities ranged from 6.3 to 10.1 t°ha—1°—1 and was roughly proportional to standing biomass. Net primary production consisted entirely of detritus. Total community autotrophic respiration ranged from 102.9—203.7 t°ha—1°yr—1 of which °70% was by foliage. Gross primary production ranged from 111.2—216.8 t°ha—1°yr—1 of which only 6.0%—7.9% was net primary production. Net ecosystem production ranged from 0.12—5.6 t°ha—1°yr—1, entirely as an accumulation of woody detritus on the soil surface. Available evidence indicates larger peak biomass in seral P. menziesii than in climax Tsuga heterophylla forests. These communities may be in the process of declining from seral peak to steady—state climax biomass.
Development of a New England Salt Marsh
Authors: Redfield Alfred C.
Published: April 2006

The salt marsh at Barnstable, Massachusetts, occupies an embayment into which it has spread during the past 4,000 years. It exhibits all stages of development from the seeding of bare sand flats through the development of intertidal marsh to the formation of mature high marsh underlain by peat deposits more than 20 ft deep. Observations and measurements of the stages of its formation are presented. The geomorphology of the marsh is considered in relation to the factors which have influenced its development, i.e., the ability of halophytes to grow at limited tide levels, the tidal regime, the processes of sedimentation, and the contemporary rise in sea level. The rates at which the early stage of development takes place have been determined by observations during a period of 12 years and the time sequence of later stages by radiocarbon analyses.
The Hubbard Brook Ecosystem Study: Productivity, Nutrients, and Phytosociology of the Herbaceous Layer
Authors: Siccama T. G. , Bormann F. H. , Likens G. E.
Published: April 2006

The herb and shrub layers of the control northern hardwood forest ecosystem at Hubbard Brook contain 96 species of plants. This ecosystem, 13.2 ha in size, has a southeast—facing aspect, an average slope of 26%, and an altitudinal range of 545 to 791 m. Vascular cryptogams, woody saplings, shrubs, tree seedlings, and herbaceous phanerogams contributed 38%, 22%, 18%, 13%, and 8% respectively to the aboveground current growth in the herb—shrub layer. Ninety—three per cent of the current growth was localized in eight species in the 1966 summer growth aspect. Dryopteris spinulosa, Viburnum alnifolium, Acer saccharum, and Fagus grandifolia contributed 67% of the cover in the herb layer, and, respectively, made up 70% of the current growth of herbs, 83% of shrubs, 61% of tree seedlings, and 90% of saplings. For the ecosystem as a whole, the herbaceous layer contained 1.8 kg/ha K, 0.3 Mg, 0.3 Ca, 0.1 S, 0.09 Mn, 0.007 Fe, 0.008 Zn, 0.001 Na, and 0.001 Cu in the aboveground current growth. The herb—shrub layer responded in several ways to the elevational complex gradient. Species diversity increased by 50% and productivity tripled in the higher portions of the ecosystem coincident with a decrease in the productivity of the overstory. Increased productivity in the herb—shrub layer resulted from more luxuriant growth of species distributed throughout the ecosystem rather than from increased species diversity. Based on a phytosociological comparison of sites occurring at similar elevations but under different geological conditions, the Hubbard Brook ecosystem is placed near the oligotrophic end of a nutrient scale for northern hardwood forest ecosystems in the mountains of New England.
Plant Communities of the Similkameen Valley, British Columbia, and Their Relationships to Soils
Authors: McLean Alastair
Published: April 2006

Five vegetation zones were recognized in the Similkameen Valley of southern British Columbia. These zones were largely controlled by elevation primarily as a reflection of climate. The climate becomes progressively more moist from east to west and with increasing elevation. Two habitat types were described in the Artemisia tridentata zone, three in the Pinus ponderosa zone, five in the Pseudotsuga menziesii zone, five in the Abies lasiocarpa zone, and one in the Alpine zone. Some habitat types correlated well with the soils at a great group level. The Pinus—Festuca habitat type was found mostly on Dark Gray soils, the Pseudotsuga—Festuca habitat type on a variety of soils, the Pseudotsuga—Calamagrostis habitat type on Gray Luvisols, the Festuca—Eriogonum habitat type on Black Chernozems, the Abies—Vaccinium—Calamagrostis habitat type on Dystric Brunisols, and the Abies—Vaccinium, Phyllodoce habitat type on Alpine Dytsric Brunisols soils. A key for the identification of the major habitat types is included.
Competition and Coexistence among Panorpa Scorpionflies (Mecoptera: Panorpidae)
Authors: Thornhill Randy
Published: April 2006

The ecological and behavioral interactions of adults of nine species of Panorpa scorpionflies were studied during 1971—1974 at eight woodland sites in southeastern Michigan, USA. The species overlap considerably in habitat use, diurnal foraging time and location, and diet. All species inhabit primarily the herb stratum of moist forests. Soft—bodied dead arthropods comprise from 88.5 to 100% of the diets of the different species. Panorpa scorpionflies are very aggressive around food. The species can be ranked linearly in relation to their ability to dominate heterospecific individuals at food. The aggressive dominance ranking of the species is related to increasing size (r = .78, P = .04). The study sites vary in Panorpa species richness from three to eight. Panorpa species clearly interact. Mark—recapture data reveal that at the site where only three species occur adults of P. banksi live longer and move less than adults of the same species at a site where six species occur. The adult seasonal distributions of the three species at the site where only three species occur are extended in comparison to the seasonal distributions of the same species at other sites with greater Panorpa species richness. Species or species groups partition the season to some extent by successional emergence. Seasonal overlap, however, is sufficient to result in competitive interactions between some species. Analyses of the seasonalities of the species reveal that the numbers of individuals and species of Panorpa present during a species' adult seasonal period inversely influence the duration of that period. The durations of the adult seasonal period of the more aggressive species are primarily influenced by the number of conspecific individuals present, whereas the durations of the adult seasonal periods of the less aggressive species are primarily influenced by the number of individuals of heterospecific and more aggressive species present. Very aggressive species cause less aggressive species to feed above the herb stratum; this may result in increased exposure to predators and to reduced longevity of the less aggressive species. I suggest that the emergence times of the species allow coexistence and have been selected in the context of interspecific competition for food. The emergence times of the species in relation to each species' aggressive dominance appears consistent with this hypothesis. The variation in species richness between sites is probably not due to the extinction of certain species because of competition, but is the result of different amounts of Panorpa habitat destruction at the sites in the past.
Biological Invasion by Myrica Faya in Hawai'i: Plant Demography, Nitrogen Fixation, Ecosystem Effects
Authors: Vitousek Peter M. , Walker Lawrence R.
Published: April 2006

Myrica faya, an introduced actinorhizal nitrogen fixer, is invading young volcanic sites in Hawaii Volcanoes National Park. We examined the population biology of the invader and ecosystem—level consequences of its invasion in open—canopied forests resulting from volcanic cinder—fall. Although Myrica faya is nominally dioecious, both males and females produce large amounts of fruit that are utilized by a number of exotic and native birds, particularly the exotic Zosterops japonica. In areas of active colonization, Myrica seed rain under perch trees of the dominant native Metrosideros polymorpha ranged from 6 to 60 seeds · m—2 · yr—1; no seeds were captured in the open. Planted seeds of Myrica also germinated and established better under isolated individuals of Metrosideros than in the open. Diameter growth of Myrica is >15—fold greater than that of Metrosideros, and the Myrica population is increasing rapidly. Rates of nitrogen fixation were measured using the acetylene reduction assay calibrated with 15N. Myrica nodules reduced acetylene at between 5 and 20 µmol · g—1 · h—1, a rate that extrapolated to nitrogen fixation of 18 kg · ha—1 · yr—1 in a densely colonized site. By comparison, all native sources of nitrogen fixation summed to 0.2 kg · ha—1 · yr—1, and precipitation added <4 kg · ha—1 · yr—1. Measurements of litter decomposition and nitrogen release, soil nitrogen mineralization, and plant growth in bioassays all demonstrated that nitrogen fixed by Myrica becomes available to other organisms as well. We concluded that biological invasion by Myrica faya alters ecosystem—level properties in this young volcanic area; at least in this case, the demography and physiology of one species controls characteristics of a whole ecosystem.
Determinants of Pattern in a New England Salt Marsh Plant Community
Authors: Bertness Mark D. , Ellison Aaron M.
Published: April 2006

In New England salt marshes, Spartina alterniflora dominates the low–marsh habitat, which is covered daily by tides. The high–marsh habitat, which is not flooded daily, is dominated on its seaward border by Spartina patens, and on its terrestrial border by Juncus gerardi. Each of these vegetation zones has a characteristic suite of physical factors associated with differences in tidal inundation. In particular, substrate redox increases and salinity decreases with decreasing marsh elevation. Although correlations between physical factors and the occurrence of specific marsh plants have been suggested to be causal, a 5–mo transplant experiment suggested that the distribution of perennials across the marsh does not correspond to their potential performance across the marsh in the absence of surrounding vegetation. While the high–marsh perennials appear to be restricted to the high–marsh habitat by harsh physical conditions in the low–marsh habitat, the low–marsh dominant, S. alterniflora, is capable of vigorous growth across the entire marsh and appears to be excluded from the high–marsh habitat by the high–marsh perennials. Throughout the high marsh, two other plant species, Distichlis spicata and Salicornia europaea, are found associated with areas that have been disturbed recently. Physical disturbance, in the form of mats of dead plant material (wrack) rafted by tides onto the marsh, is most severe in the spring and early summer, and decreases with increasing marsh elevation. Differential plant mortality results from short–term disturbance events. D. spicata and S. alterniflora are more tolerant of wrack burial than are the other marsh plants, and short–term disturbance increases the relative abundance of these species in the community. Longer lasting disturbance events kill all the underlying vegetation, leaving discrete bare patches throughout the high marsh. D. spicata rapidly colonizes these patches with vegetative runners, while S. alterniflora and Sa. europaea recruit to these patches by seed. The relative abundance of these plants in recently created bare patches exceeds greatly their relative abundance in the surrounding vegetation. Over time, however, these early colonizers are overgrown and displaced in high–marsh patches by S. patens and J. gerardi, which grow slowly, as dense turfs of roots, rhizomes, and tillers. Physical disturbance and interspecific competition appear to be major determinants of the spatial pattern of marsh plant communities. These processes will need to be considered in relation to edaphic factors in elucidating the underlying mechanisms of salt marsh plant zonation.
Population Variability and Polyphagy in Herbivorous Insect Communities
Authors: Redfearn Andrew , Pimm Stuart L.
Published: April 2006

Our purpose in this paper is to determine how the degree of polyphagy of different herbivorous insect species affects their yearly population variability. We assembled data from three studies on herbivorous insects: on British aphids, British moths, and Canadian Macrolepidoptera. Within each data set, we compared estimates of population variability across species, and related these differences to estimates of the degree of polyphagy. The degree of polyphagy was negatively correlated or uncorrelated with population variability, i.e., highly polyphagous species have a weak tendency to be less variable than host specialists. This result lends some support to MacArthur's (1955) argument that polyphagous species may be less susceptible to fluctuating resource levels. Population variability in monophagous or oligophagous herbivorous insects may, in part, reflect variation in resource levels. However, we have not yet evaluated the possibility that the levels of predation and parasitism suffered may affect variability even more strongly.
Effects of Food Availability and Fish Predation on a Zooplankton Community
Authors: Vanni Michael J.
Published: April 2006

The effects of fish predation and food availability on population densities and demography of zooplankton were investigated in Dynamite Lake, Illinois, USA, a lake with a high density of size—selective planktivorous fish and low food levels. Fish predators (bluegill sunfish) and food levels (phytoplankton) were manipulated in replicated, factorial—design field experiments during two summers (1980 and 1981). Overall, population densities of zooplankton were affected much more by manipulations of food availability than by manipulations of fish predation. The cladocerans Bosmina longirostris, Ceriodaphnia lacustris, and Diaphanosoma birgei were greatly increased in density by elevated phytoplankton levels in both years, in the presence and absence of fish. Demographic analysis in 1981 revealed that increased densities in response to elevated food levels resulted from both an increase in birth rates (Bosmina, Diaphanosoma) and a decrease in mortality rates (Ceriodaphnia, Diaphanosoma). The rotifers Lecane and Monostyla also increased dramatically in response to elevated phytoplankton densities. Copepods were less responsive to manipulations of food levels, but several taxa exhibited increases in density in response to increased phytoplankton abundance. Few species were reduced in density by fish predation. Ceriodaphnia density was reduced by fish more than any other species in the entire community, and the density of even this species was much more affected by food availability. In terms of percent change relative to controls, increased food availability had much more of an effect than fish predation on the density of most zooplankton species and on total zooplankton abundance. Fish predation had several effects on the size structure and life history traits of the cladocerans. All three species attained larger sizes when fish were excluded than when fish were present. Cladoceran individuals also initiated reproduction at a smaller size and produced smaller offspring in the presence of fish. The reductions in mean body size, size at maturity, and offspring size in the presence of fish were most pronounced in Diaphanosoma and Ceriodaphnia, the two largest species. Smaller body size and size at maturity apparently allow the cladocerans to reproduce before reaching a size at which they become vulnerable to size—selective fish predators. Larger size at first reproduction and larger offspring size in the absence of fish may be a response to invertebrate predators, which assume more importance in the absence of fish and prey most heavily on smaller size classes. Flexibility in these life—history traits allows the cladocerans to withstand what appears to be intense size—selective predation by planktivorous fish.
Fish species Diversity on Model and Natural Reef Patches: Experimental Insular Biogeography
Authors: Molles, Jr Manuel C.
Published: April 2006

Fish communities associated with model and natural reef patches were studied to determine the effects of heterogeneity, area, and isolation on the number of fish species in these systems. The effects of season and succession on the structure of these communities were also examined. Species turnover was estimated to determine if numbers of fish species on small reefs can be viewed as a balance between immigration and local extinction. Interspace size diversity, one facet of reef heterogeneity, was not positively correlated with the number of fish species on either model or natural reefs. In addition, interspace size diversity had no significant effects on species composition. In most of the cases examined reef height, another aspect of reef heterogeneity, was positively correlated with the number of fish species and species diversity, H', on natural reefs. Observations of selected fish species inhabiting model reefs support the hypothesis that vertical zonation is a means of resource partitioning in these fish communities. A negative correlation was found between reef isolation and number of fish species on patch reefs. This correlation was strongest during periods when fish population sizes were lowest. Season had more of an effect on the structure of fish communities on model reefs than did succession. Immigration and local extinction of fish species occurred on model reefs throughout the study. Patterns of immigration and extinction approximated the predictions of the MacArthur—Wilson equilibrium model of insular zoogeography when species turnover was highest.
Reproductive Ecology of Picea Mariana (Mill.) BSP., at Tree Line Near Inuvik, Northwest Territories, Canada
Authors: Black R. Alan , Bliss L. C.
Published: April 2006

Picea mariana predominates in even—aged stands of fire origin at the forest—tundra ecotone near Inuvik, Northwest Territories, Canada. Growth rates of P. mariana decrease with increasing latitude and density although growth rates do not change significantly along the ecotone. Field measurements of water relations, when compared with laboratory determinations of leaf water potentials vs. net photosynthesis, suggest no water stress related photosynthetic reduction for mature trees during 1976. Maximum and minimum leaf water potentials for mature trees were —0.6 and —2.1 MPa on 4 August and 1 July, respectively. Winter measurements of water relations also suggest no water stress. In contrast, 1st—yr seedlings demonstrated sensitivity to water stress with high rates of mortality at low levels of water loss. A macro—mesoclimatic gradient of 4°C was found across the tree line (135—km study transect). Picea mariana seed production and germination are limited by this environmental gradient to °40 km south of modern forest line. Germination and survivorship are also affected by microenvironments within a well—developed soil hummock terrain. The lower cardinal germination temperature of 15°C was the determinant of germination timing and success. Seed production estimates suggested little effect on stand reproduction with burn intervals of 100—200 yr. Shorter or longer burn intervals are believed to reduce stand reproduction. Reduced seed longevity, complete stand destruction by wild—fire, and apparent destruction of seed in the soil restrict establishment to 1—8 yr after fire. This may cause local extermination of the species or out—of—equilibrium tree line positions under conditions of deteriorating environment.
Brecht's Fatzer: Experiments in Discourse Making
Authors: Wirth Andrzej
Published: April 2006

European theatrical thinking of the last fifty years is dominated by the urge to make theatre theatrical. This urge was a reaction against the text-dominated theatre of the preceding era. Artaud, with his program of the Theatre of Cruelty, became the most radical speaker of this thinking and a trendsetter.

Artaud's contemporary, Brecht, coming from a country where a literary theatre was at home and institutionalized (Bildungstheater), demanded an intensification of its literary, “scripted” character. Brecht's postuiation of the “Literarisierung des Theaters” found the most radical application in his theory of a Lehrstück. As a matter of fact, in a way typical of Brecht's subversive strategies, it meant a sublation of the traditional notion of a literary bourgeois theatre. Nevertheless, his postuiation pronounces a program opposed to Artaud: theatre does not need to be theatrical

In Brecht's concept of a Lehrstück, it meant an elimination of an audience and a new genus proximum for theatre: learning instead of spectating or, more precisely, collective text reading.
Rasputin: A Technical Recreation
Authors: Mildenberger Marianne
Published: April 2006

The following is an attempt to reconstruct the total course of a performance of Rasputin, with special consideration to the technical data. Rasputin is the single production of the Piscatorbühne for which such a reconstruction is possible with certainty, making use of available material which has been preserved. Serving as support are the sketches by Erwin Piscator from his book Das politische Theater; an essay by Julius Richter, the technical manager of the Piscatorbühne (Rasputin/Nach der Aufführung der Piscator-Bühne in: “Die Scene” 1928, Nr.2, p.40f); notes on the technical course of “Rasputin” made by the technical office of the Piscatorbühne (Rasputin. Notes on the technical operation. Theatermuseum Clara-Ziegler-Stiftung. München) and various reviews of the production.

At the beginning of the play, the hemisphere, with the playing areas set for the first part, is completely closed. At the sound of a gong, the stage, with closed dome, revolves a half turn to the left.
Tunable DNA Cleavage by Intercalating Peptidoconjugates
Authors: Mahon Kerry P. , Roy Marc D. , Carreon Jay R. , Prestwich Erin G. , Rouge Jessica L. , Shin Stephanie , Kelley Shana O.
Published: April 2006

The properties of a novel family of peptide‐based DNA‐cleavage agents are described. Examination of the DNA‐cleavage activities of a systematic series of peptide–intercalator conjugates revealed trends that show a strong dependence on peptide sequence. Conjugates differing by a single residue displayed reactivities that varied over a wide range. The cleavage activity was modulated by the electrostatic or steric qualities of individual amino acids. Isomeric conjugates that differed in the position of the tether also exhibited different reactivities. The mechanism of DNA cleavage for these compounds was also probed and was determined to involve hydrogen‐atom abstraction from the DNA backbone. Previous studies of these compounds indicated that amino acid peroxides were the active agents in the cleavage reaction; in this report, the chemistry underlying the reaction is characterized. The results reported provide insight into how peptide sequences can be manipulated to produce biomimetic compounds.
Enantioselective 2‐hydroxylation of RS‐8359, a selective and reversible MAO‐A inhibitor, by cytochrome P450 in mouse and rat liver microsomes
Authors: Itoh Kunio , Nishiya Yumi , Takasaki Wataru , Adachi Mayuko , Tanaka Yorihisa
Published: April 2006

RS‐8359, (±)‐4‐(4‐cyanoanilino)‐5,6‐dihydro‐7‐hydroxy‐7H‐cyclopenta[d]‐pyrimidine is a racemic compound with a selective and reversible monoamine oxidase A (MAO‐A) inhibition activity. The substrate and product enantioselectivity with respect to 2‐hydroxylation of RS‐8359 enantiomers was studied using mouse and rat liver microsomes. In mice, the (S)‐enantiomer was transformed to the cis‐diol metabolite, whereas the (R)‐enantiomer to the trans‐diol metabolite. The Vmax/Km value for the formation of the cis‐diol metabolite from the (S)‐enantiomer was sevenfold greater than that for the formation of the trans‐diol metabolite from the (R)‐enantiomer. The greater Vmax/Km value for the (S)‐enantiomer was due to the tenfold smaller Km value compared to that for the (R)‐enantiomer. The results were in fair agreement with the previously reported low plasma concentrations of the (S)‐enantiomer and the high recovery of the cis‐diol metabolite derived from the (S)‐enantiomer in urine after oral administration of RS‐8359 to mice. Similarly to mice, in rats the (R)‐enantiomer was transformed to the trans‐diol metabolite, whereas the (S)‐enantiomer yielded the cis‐diol and trans‐diol metabolites. The Vmax/Km value for the (R)‐enantiomer was larger than that for the (S)‐enantiomer in rats, indicating that the low plasma concentration of the (S)‐enantiomer in rats might be caused by a metabolic reaction other than P450‐dependent hydroxylation. CYP3A was shown to be responsible for the trans‐diol formation from the (R)‐enantiomer. Chirality, 2006. © 2006 Wiley‐Liss, Inc.
Synthesis, Structures and Catecholase Activity of a New Series of Dicopper(II) Complexes of Reduced Schiff Base Ligands
Authors: Sreenivasulu Bellam , Zhao Fei , Gao Song , Vittal Jagadese J.
Published: April 2006

A series of dinuclear CuII complexes of reduced Schiff bases from substituted salicylaldehydes and amino acids have been synthesized and characterized. They are: [Cu2(RScp11)2(H2O)2] {H2RScp11 = 1‐[(2‐hydroxy‐5‐R‐benzyl)amino]cyclopentane‐1‐carboxylic acid; R = H (1), Cl (2), CH3 (3), OH (4)}, [Cu2(RSch11)2(H2O)x] {H2RSch11 = 1‐[(2‐hydroxy‐5‐R‐benzyl)amino]cyclohexane‐1‐carboxylic acid; R = H and x = 1 (5), R = Cl and x = 2 (6), R = CH3 and x = 2 (7)}, [Cu2(RSch12)2(H2O)2] {H2RSch12 = 2‐[(2‐hydroxy‐5‐R‐benzyl)amino]cyclohexane‐1‐carboxylic acid; R = H (8), CH3 (10) and [Cu2(ClSch12)2]·2H2O (9)}, [Cu2(Diala5)2(H2O)2]·H2O [H3Diala5 = N‐(2,5‐dihydroxybenzyl)‐L‐alanine] (11), [Cu2(Diala4)2(H2O)2]·H2O [H3Diala4 = N‐(2,4‐dihydroxybenzyl)‐L‐alanine] (12), and [Cu2(Diala3)2(H2O)2]·H2O [H3Diala3 = N‐(2,3‐dihydroxybenzyl)‐L‐alanine] (13). They were isolated and characterized by chemical and spectroscopic methods. Single crystal X‐ray crystallographic studies have revealed that [Cu2(Scp11)2(MeOH)2] (1a), [Cu2(ClScp11)2(DMF)(H2O)]·MeCN (2a), [Cu2(MeScp11)2(MeOH)2]·2 MeOH (3a), [Cu2(ClSch11)2(MeOH)2]·2 MeOH (6a), [Cu2(ClSch12)2]·2 MeOH (9a), and [Cu2(Diala4)2(DMSO)2]·2 DMSO·2 acetone (12a) have 1D hydrogen‐bonded polymeric structures while 4 has a 3D hydrogen‐bonded network structure. Complex 8 displays a 2D coordination polymeric network structure. The complexes 1–13 have been investigated as functional models for the catechol oxidase by employing 3,5‐di‐tert‐butylcatechol as a model substrate. Electron‐withdrawing substituents reduced the activity while electron‐donating substituents enhanced the activity. Variable‐temperature magnetic studies conducted on compound 8 suggest the presence of strong inter‐dimer antiferromagnetic coupling. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis of 1,5‐Substituted Iminodibenzo[b,f][1,5]diazocine, an Analogue of Tröger’s Base
Authors: Leganza Alessandro , Bezze Chiara , Zonta Cristiano , Fabris Fabrizio , De Lucchi Ottorino , Linden Anthony
Published: April 2006

A method for the synthesis of 1,5‐disubstituted iminodibenzo[b,f][1,5]diazocines is presented. The synthesis is achieved by the metal‐free cyclization of 2‐aminophenyl ketimines using the corresponding 2‐aminophenyl ketone as the catalyst. The synthesis gives new insight into the mechanism of formation of this class of compounds. The presence of potential sites for hydrogen‐bond formation and two aromatic bromine atoms available for functionalization make these targets attractive for further development in supramolecular chemistry. The structure of the complex derived from the iminodibenzo[b,f][1,5]diazocine and PdCl2 was determined by X‐ray crystallography. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Central bank interventions in industrialized countries: a characterization based on survey results
Authors: Lecourt Christelle , Raymond Helene
Published: April 2006

This paper presents the findings from a survey on central banks' FOREX intervention practices in industrialized countries over the last decade. The answers of responding monetary authorities are examined with respect to available data and literature. Our findings indicate that interventions usually take place during normal working hours while central banks show some preference for dealing with major domestic banks. Correction or prevention of long‐term misalignments of exchange rates with their fundamental values and, to a lesser extent, the reduction of exchange rate volatility is the first motive given for intervention. The signalling effect of interventions is consistently put forward as the main channel through which interventions work. Copyright © 2006 John Wiley & Sons, Ltd.
The public scholarship: Reintegrating Boyer's four domains
Authors: Colbeck Carol L. , Michael Patty Wharton
Published: April 2006

The authors argue for integrating Boyer's four domains through the pursuit of public scholarship.
Exploring the dimensions of the scholarship of teaching and learning: Analytics for an emerging literature
Authors: Paulsen Michael B. , Feldman Kenneth A.
Published: April 2006

This chapter examines the construct scholarship of teaching and learning using a Parsonian four‐function paradigm that serves as an analytical structure for organizing and examining some of the key issues in the emerging literature.
UV laser ablation and plasma treatment of wooden surfaces
– a comparing investigation
Authors: Mertens N , Wolkenhauer A , Leck M , Viöl W
Published: April 2006

Using UV short-wavelength laser irradiation, the layer
of mechanically damaged cells on wooden surfaces can be removed.
Four excimer lasers (157 nm, 193 nm, 248 nm, 308 nm) were used to
compare the ablation of wooden surfaces by different UV
wavelengths. The ablation depth was measured by using optical
microscopy. LV-SEM was applied to determine the appearance and
quality of the laser ablation. In addition to the ablation process
the laser can be used also to influence the surface energy. As the
same effect can be achieved by plasma treatment of wooden
surfaces, both methods were compared. The comparison was made by
means of the water droplet test. The plasma treatment was carried
out at atmospheric pressure as a dielectric barrier discharge. Two
types of wood were determined: beech and thermowood beech.
Thermowood is a heat treated lumber product especially made for
outdoor applications. It was examined, whether the thermal
treatment of wood influences the characteristic changes of the
laser ablation and the plasma treatment. With the researched
wavelengths, homogeneous ablation is possible. The absorption time
can be reduced both with laser ablation and plasma treatment,
whereas plasma treatment causes a stronger effect. A combined
treatment improves the effect additionally.
Edge waves on a gently sloping beach
Authors: Miles John
Published: April 2006

Edge waves of frequency ω and longshore wavenumber k in water of depth h(y) = h1H(σy/h1), 0 [les ] y < ∞, are calculated through an asymptotic expansion in σ/kh1 on the assumptions that σ [Lt ] 1 and kh1 = O(1). Approximations to the free-surface displacement in an inner domain that includes the singular point at h = 0 and the turning point near gh ≈ ω2/K2 and to the eigenvalue λ ≡ ω2/σgh are obtained for the complete set of modes on the assumption that h(y) is analytic. A uniformly valid approximation for the free-surface displacement and a variational approximation to Λ are obtained for the dominant mode. The results are compared with the shallow-water approximations of Ball (1967) for a slope that decays exponentially from σ to 0 as h increases from 0 to h1 and of Minzoni (1976) for a uniform slope that joins h = 0 to a flat bottom at h = h1 and with the geometrical-optics approximation of Shen, Meyer & Keller (1968).
Symmetry-breaking bifurcations in resonant surface waves
Authors: Feng Z. C. , Sethna P. R.
Published: April 2006

Surface waves in a nearly square container subjected to vertical oscillations are studied. The theoretical results are based on the analysis of a derived set of normal form equations, which represent perturbations of systems with 1:1 internal resonance and with D4 symmetry. Bifurcation analysis of these equations shows that the system is capable of periodic and quasi-periodic standing as well as travelling waves. The analysis also identifies parameter values at which chaotic behaviour is to be expected. The theoretical results are verified with the aid of some experiments.
Dynamic simulation of bounded suspensions of hydrodynamically interacting particles
Authors: Durlofsky Louis J. , Brady John F.
Published: April 2006

A general method for computing the hydrodynamic interactions among an infinite suspension of particles immersed between two infinite plane boundaries, under the condition of vanishing particle Reynolds number, is presented. The method accounts for both near-field particle-particle and particle-boundary lubrication effects as well as dominant many-body effects, which include reflections with both particles and boundaries. Through relative motion of the boundaries, a bulk shear flow can be generated, and the resulting particle motions, as well as the forces exerted by the boundaries on the fluid, computed. Knowledge of the boundary forces allows for the calculation of the suspension viscosity. The simulation method is applied to several example problems; in one, the resuspension of a sediment layer of particles is illustrated. The general method can also be extended to dynamically simulate suspensions immersed in a pressure driven flow between two walls or through a tube.
On flow separation and reattachment around a circular cylinder at critical Reynolds numbers
Authors: Higuchi H. , Kim H. J. , Farell C.
Published: April 2006

An experimental investigation of the flow around smooth circular cylinders in the Reynolds number range 0.8 × 105<Re< 2 × 105is presented. Measured quantities include spectra, spanwise correlations and cross correlations of cylinder pressures and wake-velocity fluctuations, and low-frequency boundary-layer flow direction reversals near separation. The flow motion in the critical range is found to be characterized by intermittent, symmetric boundary-layer reattachments, occurring in cells with a well-defined spanwise structure, accompanying a significant decrease in drag coefficient and a weakening of the vortex shedding.
Capillary–gravity waves of solitary type on deep water
Authors: Longuet-Higgins Michael S.
Published: April 2006

On physical grounds it was recently suggested that limiting capillary–gravity waves of solitary type may exist on the surface of deep water (Longuet-Higgins 1988). This paper describes accurate numerical calculations which support the conjecture. The limiting wave has a phase speed c = 0.9267 (gτ)¼. It is one of a family of solitary waves having speeds c [les ] 1.30 (gτ)¼. The maximum angle of inclination αmax of the free surface is a monotonically decreasing function of the speed c. Physical arguments suggest that αmax has a positive lower bound.
One-dimensional model for the Rijke tube
Authors: Nicoli C. , Pelcé P.
Published: April 2006

We develop a simple model in which longitudinal, compressible, unsteady heat transfer between heater and gas is computed in the small-Mach-number limit. This calculation is used to determine the transfer function of the heater, which plays an important role in the stability limits of the thermoacoustic instability of the Rijke tube. The transfer function is determined analytically in the limit of small expansion parameter γ, and numerically for γ of order unity. In the case ρμ/cp = constant, an analytical solution can be found.
Breaking of wind-generated waves: measurements and characteristics
Authors: Hwang Paul A. , Xu Delun , Wu Jin
Published: April 2006

A method of using local wave properties to provide a detailed description of breakings in a random wave field is developed. These properties, derived through the Hilbert transform, include the angular frequency, phase velocity, and surface-velocity components. The breaking characteristics are presented, including the probability of breaking, its time- and lengthscales, its intensity, and the phase of its inception. The time- and lengthscales, of breaking events were found to be linearly proportional to the corresponding scales of underlying waves, and to indicate that the breaking region is geometrically similar. Consistent results were obtained from temporal and spatial measurements. Finally, on the basis of these results we have evaluated geometric and kinematic criteria for identifying breaking waves.
Reynolds stress development in pressure-driven three-dimensional turbulent boundary layers
Authors: Anderson Shawn D. , Eaton John K.
Published: April 2006

The development of the Reynolds stress field was studied for flows in which an initially two-dimensional boundary layer was skewed sideways by a spanwise pressure gradient ahead of an upstream-facing wedge. Two different wedges were used, providing a variation in the boundary-layer skewing. Measurements of all components of the Reynolds stress tensor and all ten triple products were measured using a rotatable cross-wire anemometer. The results show the expected lag of the shear stress vector behind the strain rate. Comparison of the two present experiments with previous data suggests that the lag can be estimated if the radius of curvature of the free-stream streamline is known. The magnitude of the shear stress vector in the plane of the wall is seen to decrease rapidly as the boundary-layer skewing increases. The amount of decrease is apparently related to the skewing angle between the wall and the free stream. The triple products evolve rapidly and profiles in the three-dimensional boundary layer are considerably different than two-dimensional profiles, leaving little hope for gradient transport models for the Reynolds stresses. The simplified model presented by Rotta (1979) performs reasonably well providing that an appropriate value of the T-parameter is chosen.
Spectral approach to non-isotropic turbulence subjected to rotation
Authors: Cambon C. , Jacquin L.
Published: April 2006

The non-isotropic effects of solid-body rotation on homogeneous turbulence are investigated in this paper. A spectral formalism using eigenmodes introduces the spectral Coriolis effects more easily and leads to simpler expressions for the integral quadratic terms which come mostly from classical two-point closures. The analysis is then applied to a specific eddy damped quasi-normal Markovian model, which includes the inertial waves regime in the evaluation of triple correlations. This procedure allows for a departure from isotropy by external rotation effects. When started with rigorously isotropic initial data, the various trends observed on the Reynolds stresses and the integral lengthscales remain in accordance with the results from direct simulations; moreover they reflect a very specific spectral angular distribution. Such an angular dependence allows a drain of spectral energy from the parallel to the normal wave vectors (with respect to the rotation axis), and thus appears consistent with a trend toward two-dimensionality.
The linear stability of viscous compressible plane Couette flow
Authors: Glatzel W.
Published: April 2006

The structure of normal modes in viscous compressible plane Couette flow is investigated. The spectrum is found to consist of two types of modes: the viscous modes, which obtain finite phase velocities by the mechanism of mode pairing; and the sonic modes, whose phase velocity becomes distorted in the supersonic regime. This leads to mode crossings which unfold, depending on the type of crossing modes, either into purely sonic or viscous-sonic instability bands. The latter provide a new example for viscous instability. Both mode pairing of viscous modes and distortion of the phase velocity of sonic modes is caused by the shear. Critical Reynolds numbers for the instabilities are derived.
Three-dimensional thermal convection in a spherical shell
Authors: Bercovici D. , Schubert G. , Glatzmaier G. A. , Zebib A.
Published: April 2006

Independent pseudo-spectral and Galerkin numerical codes are used to investigate three-dimensional infinite Prandtl number thermal convection of a Boussinesq fluid in a spherical shell with constant gravity and an inner to outer radius ratio equal to 0.55. The shell is heated entirely from below and has isothermal, stress-free boundaries. Nonlinear solutions are validated by comparing results from the two codes for an axisymmetric solution at Rayleigh number Ra = 14250 and three fully three-dimensional solutions at Ra = 2000, 3500 and 7000 (the onset of convection occurs at Ra = 712). In addition, the solutions are compared with the predictions of a slightly nonlinear analytic theory. The axisymmetric solution is equatorially symmetric and has two convection cells with upwelling at the poles. Two dominant planforms of convection exist for the three-dimensional solutions: a cubic pattern with six upwelling cylindrical plumes, and a tetrahedral pattern with four upwelling plumes. The cubic and tetrahedral patterns persist for Ra at least up to 70000. Time dependence does not occur for these solutions for Ra [les ] 70000, although for Ra > 35000 the solutions have a slow asymptotic approach to steady state. The horizontal and vertical structure of the velocity and temperature fields, and the global and three-dimensional heat flow characteristics of the various solutions are investigated for the two patterns up to Ra = 70000. For both patterns at all Ra, the maximum velocity and temperature anomalies are greater in the upwelling regions than in the downwelling ones and heat flow through the upwelling regions is almost an order of magnitude greater than the mean heat flow. The preferred mode of upwelling is cylindrical plumes which change their basic shape with depth. Downwelling occurs in the form of connected two-dimensional sheets that break up into a network of broad plumes in the lower part of the spherical shell. Finally, the stability of the two patterns to reversal of flow direction is tested and it is found that reversed solutions exist only for the tetrahedral pattern at low Ra.
On unsteady surface forces, and sound produced by the normal chopping of a rectilinear vortex
Authors: Howe M. S.
Published: April 2006

An investigation is made of the sound produced when a rectilinear vortex is cut at right angles to its axis by a non-lifting airfoil of symmetric section. The motions are at sufficiently low Mach number that the wavelength of the sound is large relative to the chord of the airfoil. In these circumstances the airfoil experiences no fluctuating lift during the interaction, and the radiation may be ascribed to an acoustic source of dipole type whose strength is equal to the unsteady drag. It is argued that previous analyses of the related problem of ‘unsteady thickness noise’ have ignored certain terms whose inclusion greatly reduces the predicted intensity of the radiation. A general formula for the surface forces (derived in an appendix) is applied to deduce that the dipole strength is proportional to the square of the circulation of the vortex, and depends on the spanwise acceleration of the vortex induced by images in the airfoil. Numerical results are presented for typical airfoil sections, and a comparison is made with the unsteady lifting noise generated when the axis of the vortex is inclined at a small angle to the normal to the median plane of the airfoil.