bluuebunny/crossref_metadata_2025_split huggingface dataset:
High diversity of the ‘Spumella‐like’ flagellates: an investigation based on the SSU rRNA gene sequences of isolates from habitats located in six different geographic regions
Authors: Boenigk Jens , Pfandl Karin , Stadler Peter , Chatzinotas Antonis 
Published: April 2005

SummaryWe isolated 28 strains of ‘Spumella‐like’ flagellates from different freshwater and soil habitats in Austria, People's Republic of China, Nepal, New Zealand, Uganda, Kenya, Tanzania and Hawaii by use of a modified filtration–acclimatization method. ‘Spumella‐like’ flagellates were found in all of the samples and were often among the dominant bacterivorous flagellates in the respective environments. The small subunit ribosomal RNA (SSU rRNA) gene sequence of the isolates was determined and aligned with previously published sequences of members belonging to the Chrysophyceae sensu stricto. Phylogenetic analysis of the 28 new sequences confirmed their position within the Chrysophyceae sensu stricto and positioned them within different clades. Most of the sequences grouped within clade C and formed several subclusters separated from each other by green taxa including flagellates belonging to Ochromonas, Dinobryon, Poterioochromonas and others. All soil isolates clustered together (subcluster C1) with the soil strain Spumella elongata and the undescribed soil strain ‘Spumella danica’. Aquatic isolates were affiliated with at least two branches (C2 and C3). Sequence similarity to the closest related member of the Chrysophyceae ranged between 92% and 99.6%, sequence divergence among the ‘Spumella‐like’ flagellates was as high as 10%. We conclude that (i) the ‘Spumella‐like’ flagellates are a diverse group both in terms of sequence dissimilarity between isolates and in terms of the number of genotypes, (ii) Spumella and Ochromonas are polyphyletic, and (iii) based on the SSU rRNA gene no biogeographical restriction of certain branches could be observed even though different ecotypes may be represented by the same genotype.
Use of monoclonal antibodies to quantify the dynamics of α‐galactosidase and endo‐1,4‐β‐glucanase production by Trichoderma hamatum during saprotrophic growth and sporulation in peat
Authors: Thornton Christopher R. 
Published: April 2005

Summary Trichoderma species are ubiquitous soil and peat‐borne saprotrophs that have received enormous scientific interest as biocontrol agents of plant diseases caused by destructive root pathogens. Mechanisms of biocontrol such as antibiosis and hyperparasitism are well documented and the biochemistry and molecular genetics of these processes defined. An aspect of biocontrol that has received little attention is the ability of Trichoderma species to compete for nutrients in their natural environments. Trichoderma species are efficient producers of polysaccharide‐degrading enzymes that enable them to colonize organic matter thereby preventing the saprotrophic spread of plant pathogens. This study details the use of monoclonal antibodies (mAbs) to quantify the production of two enzymes implicated in the saprotrophic growth of Trichoderma species in peat. Using mAbs specific to the hemicellulase enzyme α‐galactosidase (AGL) and the cellulase enzyme endo‐1,4‐β‐glucanase (EG), the relationship between the saprotrophic growth dynamics of a biocontrol strain of Trichoderma hamatum and the concomitant production of these enzymes in peat‐based microcosms was studied. Enzyme activity assays and enzyme protein concentrations derived by enzyme‐linked immunosorbent assay (ELISA) established the precision and sensitivity of mAb‐based assays in quantifying enzyme production during active growth of the fungus. Trends in enzyme activities and protein concentrations were similar for both enzymes, during a 21‐day sampling period in which active growth and sporulation of the fungus in peat was quantified using an independent mAb‐based assay. There was a sharp increase in active biomass of T. hamatum 3 days after inoculation of microcosms with phialoconidia. After 3 days there was a rapid decline in active biomass which coincided with sporulation of the fungus. A similar trend was witnessed with EG activities and concentrations. This showed that EG production related directly to active growth of the fungus. The trend was not found, however, with AGL. There was a rapid increase in enzyme activities and protein concentrations on day 3, after which they remained static. The reason for the maintenance of elevated AGL probably resulted from secretion of the enzyme from conidia and chlamydospores. ELISA, immunofluoresence and immunogold electron microscopy studies of these cells showed that the enzyme is localized within the cytoplasm and is secreted extracellularly into the surrounding environment. It is postulated that release of oligosaccharides from polymeric hemicellulose by the constitutive spore‐bound enzyme leads to AGL induction and could act as an environmental cue for spore germination.
Hydrothermal vent gastropods from the same family (Provannidae) harbour ɛ‐ and γ‐proteobacterial endosymbionts
Authors: Urakawa Hidetoshi , Dubilier Nicole , Fujiwara Yoshihiro , Cunningham Dale E. , Kojima Shigeaki , Stahl David A. 
Published: April 2005

SummaryThe discovery of new hydrothermal vent systems in the back‐arc basins of the Western Pacific revealed chemosynthesis‐based faunal communities distinct from those of other vents. These vents are dominated by two related gastropods (Alviniconcha spp. and Ifremeria nautilei) that harbour symbiotic bacteria in their gills. We used comparative 16S ribosomal RNA (rRNA) gene sequencing and in situ hybridization with rRNA‐targeted probes to characterize the bacterial symbionts of Alviniconcha sp. and I. nautilei from the Manus Basin in the Western Pacific. The analyses revealed that these two gastropod species, although affiliated with the same family, harbour phylogenetically distant chemosymbionts, suggesting independent origins of these endosymbioses. The I. nautilei endosymbiont clusters with sulfur‐oxidizing bacteria within the γ‐Proteobacteria, as is the case for all previously characterized endosymbionts from a wide diversity of host taxa harbouring thioautotrophic prokaryotes. In contrast, the Alviniconcha endosymbiont is affiliated with sulfur‐oxidizing bacteria within the ɛ‐Proteobacteria. These results show that bacteria from the ɛ‐Proteobacteria are also capable of forming endosymbiotic associations with marine invertebrates from chemosynthetic environments. More generally, the endosymbiotic lifestyle is now shown to be distributed throughout all recognized classes of the Proteobacteria.
Recent advances in sea‐ice microbiology
Authors: Mock Thomas , Thomas David N. 
Published: April 2005

SummaryOver the past 50 years there has been much effort invested in the investigation of the ecology of sea ice. Sea ice is an ephemeral feature of the Arctic and Southern Oceans and smaller water bodies such as the Baltic and Caspian Seas. The semisolid ice matrix provides a range of habitats in which a diverse range of microbial organisms thrive. In the past 5 years there has been considerable steps forward in sea‐ice research, in particular regarding the analysis of sea‐ice microstructure and the investigation of the diversity and adaptation of microbial communities. These studies include: (i) controlled simulated and in situ studies on a micrometer scale to unravel the dynamic of the microhabitat with consequences for the organisms;  (ii)  the  introduction  of  molecular  approaches to uncover the diversity of uncultured still unknown microorganisms; and (iii) studies into the molecular adaptation of selected model organisms to the extreme environment. This minireview presents some of the most recent findings from sea‐ice studies within the framework of these aims.
Young children have difficulty ascribing true beliefs
Authors: Riggs Kevin J. , Simpson Andrew 
Published: April 2005

AbstractUsing the format of a false belief task (Wimmer & Perner, 1983), we investigated the ability of 88 3‐ and 4‐year‐olds to ascribe a previously held true belief to a story protagonist. In an unexpected transfer task, children found true belief ascription as difficult as false belief ascription even though they could answer memory questions about story details. Results are discussed in relation to theoretical accounts of theory of mind development that stress the importance of understanding the falsity of belief, and those accounts that stress the importance of information or executive processes.
Doublet challenge: form comes before function in children's understanding of their orthography
Authors: Lehtonen Annukka , Bryant Peter 
Published: April 2005

Abstract Several current spelling models suggest that children cannot have any knowledge of orthographic form before they have acquired knowledge about orthographic function. We evaluated this proposition by using an orthographic choice task to inspect Finnish schoolchildren's knowledge of two aspects of consonant doublet use: the allowed doublet position (an aspect of orthographic form) and the type of phonemic information they represent (an aspect of orthographic function). The results challenged the view of the existing spelling models, since they showed that already at the beginning of the first school year children possessed formal knowledge of doublet use and knew that word‐initial doublets are not allowed. However, these children were ignorant of the function of doublets, i.e. that they stand for long consonants.
Processing demands in belief‐desire reasoning: inhibition or general difficulty?
Authors: Friedman Ori , Leslie Alan M. 
Published: April 2005

Abstract Most 4‐year‐olds can predict the behavior of a person who wants an object but is mistaken about its location. More difficult is predicting behavior when the person is mistaken about location and wants to avoid the object. We tested between two explanations for children's difficulties with avoidance false belief: the Selection Processing model of inhibitory processing and a General Difficulty account. Children were presented with a false belief task and a control task, in which belief attribution was as difficult as in the false belief task. Predicting behavior in light of the character's desire to avoid the object added more difficulty in the false belief task. This finding is consistent with the Selection Processing model, but not with the General Difficulty account.
Breakdown of spatial parallel coding in children's drawing
Authors: De Bruyn Bart , Davis Alyson 
Published: April 2005

Abstract When drawing real scenes or copying simple geometric figures young children are highly sensitive to parallel cues and use them effectively. However, this sensitivity can break down in surprisingly simple tasks such as copying a single line where robust directional errors occur despite the presence of parallel cues. Before we can conclude that this directional bias is a limiting case it needs to be shown that any given parallel cues are indeed being processed. We achieved this by using a texture‐defined contour where parallel cues are integral to the stimulus and thus cannot be ignored. Here we report that even when prolific parallel cues must have been processed, young children make robust directional errors when copying single lines. This finding demonstrates a major constraint on young children's spatial parallel coding.
Can chimpanzee infants (Pan troglodytes) form categorical representations in the same manner as human infants (Homo sapiens)?
Authors: Murai Chizuko , Kosugi Daisuke , Tomonaga Masaki , Tanaka Masayuki , Matsuzawa Tetsuro , Itakura Shoji 
Published: April 2005

Abstract We directly compared chimpanzee infants and human infants for categorical representations of three global‐like categories (mammals, furniture and vehicles), using the familiarization–novelty preference technique. Neither species received any training during the experiments. We used the time that participants spent looking at the stimulus object while touching it as a measure. During the familiarization phase, participants were presented with four familiarization objects from one of three categories (e.g. mammals). Then, they were tested with a pair of novel objects, one was a familiar‐category object and another was a novel‐category object (e.g. vehicle) in the test phase. The chimpanzee infants did not show significant habituation, whereas human infants did. However, most important, both species showed significant novelty‐preference in the test phase. This indicates that not only human infants, but also chimpanzee infants formed categorical representations of a global‐like level. Implications for the shared origins and species‐specificity of categorization abilities, and the cognitive operations underlying categorization, are discussed.
Form, function and environments of the early angiosperms: merging extant phylogeny and ecophysiology with fossils
Authors: Feild Taylor S. , Arens Nan Crystal 
Published: April 2005

SummaryThe flowering plants – angiosperms – appeared during the Early Cretaceous period and within 10–30 Myr dominated the species composition of many floras worldwide. Emerging insights into the phylogenetics of development and discoveries of early angiosperm fossils are shedding increased light on the patterns and processes of early angiosperm evolution. However, we also need to integrate ecology, in particular how early angiosperms established a roothold in pre‐existing Mesozoic plant communities. These events were critical in guiding subsequent waves of angiosperm diversification during the Aptian–Albian. Previous pictures of the early flowering plant ecology have been diverse, ranging from large tropical rainforest trees, weedy drought‐adapted and colonizing shrubs, disturbance‐ and sun‐loving rhizomatous herbs, and, more recently, aquatic herbs; however, none of these images were tethered to a robust hypothesis of angiosperm phylogeny. Here, we synthesize our current understanding of early angiosperm ecology, focusing on patterns of functional ecology, by merging recent molecular phylogenetic studies and functional studies on extant ‘basal angiosperms’ with the picture of early angiosperm evolution drawn by the fossil record.

Contents

Summary
383

I.
Introduction
384

II.
Previous images of early angiosperms and their habitats
385

III.
Progress in understanding angiosperm phylogeny: extant ‘basal’ relations
386

IV.
Early angiosperm ecology: inferences from extant plants and reflections from the fossil record
387

V.
The ecology of angiosperm diversification: gaining a roothold and subsequent diversification
397

VI.
The environmental context of early angiosperm evolution
399

VII.
Conclusions
402

Acknowledgements
402

References
402
Sulfur and phytoplankton: acquisition, metabolism and impact on the environment
Authors: Giordano Mario , Norici Alessandra , Hell Ruediger 
Published: April 2005

SummarySulfur emission from marine phytoplankton has been recognized as an important factor for global climate and as an entry into the biogeochemical S cycle. Despite this significance, little is known about the cellular S metabolism in algae that forms the basis of this emission. Some biochemical and genetic evidence for regulation of S uptake and assimilation is available for the freshwater model algaChlamydomonas. However, the marine environment is substantially different from most freshwaters, containing up to 50 times higher free sulfate concentrations and challenging the adaptive mechanisms of primary and secondary S metabolism in marine algae. This review intends to integrate ecological and physiological data to provide a comprehensive view of the role of S in the oceans.ContentsSummary371IIntroduction371IIAtmospheric sulfur deposition372IIISulfur in aquatic ecosystems372IVSulfur acquisition by algae373VAssimilation and reduction of sulfate by algae374VIInteractions between S and C, N, P metabolism376VIIRegulation of sulfur metabolism377VIIISulfur release by algae: the role of DMS377IXThe pathway of DMSP biosynthesis378References379
NEEDS FOR CONSISTENCY AND FLEXIBILITY IN MEASURES OF REAL PRODUCT BY INDUSTRY1
Authors: Moss Milton 
Published: April 2005

Study of relationships between outputs, inputs, prices, and final demands in the United States can be strengthened by: (1) eliminating disparities in official measures of output (mainly the Index of Industrial Production and Real Gross National Product), and (2) obtaining agreement on the conceptual framework for studying these relationships.Real Gross Product has provided a consistent framework for study of productivity and prices for the total economy and for broad industry groups, but has not easily permitted the analysis of commodity detail particularly for intermediate commodities. Industrial Production, on the other hand, has considerably extended the detailed analysis of commodity output but has not provided a basis for systematic analysis of productivity and prices within a consistent framework for the total economy.This paper illustrates the effect of some of the disparities between Industrial Production and Gross Product in manufacturing on the analysis of relations between prices and output and prices and productivity. This is done for the 1954–1958 period when benchmark data are available for both measures. Inconsistencies for a number of industries cause difficulties in analyzing the interplay of demand and cost influences on price changes; for example, industries which rise above average in output and below in price in one measure are not the same as those in similar price‐quantity relationships in the other measure.The paper concludes by recommending improvements in data and concept in order to eliminate some of the disparities and to enable analysts to reap the benefits of both types of measures of real output.
WHY GROWTH RATES DIFFER—A SUMMARY AND APPRAISAL
Authors: Daly D. J. 
Published: April 2005

This review article initially summarizes some of the highlights of the volume Why Growth Rates Differ, including the use of income shares as weights for the various factor inputs and some of the major factual conclusions drawn from the inter‐country comparisons. Some of the main factors in differences in income levels and differences in growth rates are then reviewed.In appraising the contribution of the volume, the monumental task is emphasized. This study illustrates the adaptability of the approach which Denison developed initially in The Sources of Economic Growth. The volume meets many of the questions and criticisms raised of his earlier study, and should encourage a shift of the discussion from methodology towards the substance of the empirical results.The volume introduces some shifts in emphasis on the importance of different factors in growth. The role of demand variations and the contribution of capital is considered, but the evidence in the volume gives less emphasis on the importance of these factors than earlier work by others in both the United States and Europe. The volume gives some emphasis to shifts out of agriculture and the self‐employed in the high postwar growth in many individual European countries. It considers the effects of reductions in trade barriers, and follows the view of most economists in playing this down. Advances in knowledge are also considered.Those who are interested in questions of economic growth, past and future, and economic policy in this area will find much in this volume for study and reflection.
INTERTEMPORAL COMPARABILITY OF NATIONAL INCOME IN CZECHOSLOVAKIA
Authors: Kreči Jaroslav 
Published: April 2005

The national income and product account (United Nations concept) in current prices itemized by distributive shares and by type of expenditure is given for the period 1929–1937. The national income by industrial origin and the reproducible national wealth are computed for the year 1930. Differences between the U.N. and the material concept are explained by means of the 1939 data.The national product series in real terms are computed (a) by means of the price deflation of the types of expenditure, and (b) as the physical output of goods and services by industrial origin (since 1926). Major changes In distributive shares are explained with the help of Price‐cost analysis.The national product in real terms attains the lowest point in 1935 and not in 1933, as the industrial production and foreign trade series indicate. The structure of gross national expenditure reveals the same pattern of shifts, as is well known from other industrially developed countries during the business cycle.The development of national product by industrial origin, however, reveals some conspicuous singularities. Especially the uninterrupted increase in trade services (in terms of both persons engaged and turnover in constant prices) is an anomaly in the period of 1929–1937.Further, the Increase of rent (due to the gradual abolition of rent control), contrasting with the general fall of prices, led to a major shift in the distribution of national income during the early thirties. The other remarkable change resulting mainly from the changing price structure was the decrease of the farmers' share in national income.The production, transportation and distribution series in real terms reveal some time‐lags. These result partly from the shift from the foreign to the home market, partly from the compensatory effects of stock movements, and partly from the delayed adjustment of consumers to declining income.
MÉTHODES DE CALCUL DU REVENU NATIONAL AUX PRIX CONSTANTS UTILISEES PAR LE SERVICE DE LA STATISTIQUE YOUGOSLAVE
Authors: Kitaljević Boško 
Published: April 2005

Cet article résume brièvement les méthodes utilisées par le Service de la statistíque yougoslave dans le calcul du revenu national aux prix constants. En ce qui concerne l'industrie, la méthode utilisée consiste à multiplier le revenu net par unité dans l'annCe de base (distribué par type) par les quantités produites dans l'année en cours. Cet article discute également des autres méthodes possibles, et fait ressortir les raisons qui se trouvent à la base des choix effectués.La partie finale examine la validité des mesures obtenues; elle met en garde contre la tentation de procéder a des interprétations de caractére normatif sur la base de prix déterminés par voie administrative ou sujets a d'autres types de distortions. Des données, classées par industrie et par région, sont fournies pour la periode 1952–1965.