bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of large‐scale stocking of early stages of brown trout, Salmo trutta, to angler catches in the French–Swiss part of the River Doubs
Authors: Champigneulle A. , Cachera S. 
Published: December 2004

AbstractAround 500 000 brown trout, Salmo trutta L., alevins are stocked annually in the 24‐km section of the River Doubs under study. All the alevins stocked in the period 1994–1996 were identifiable by fluoromarking their otoliths with tetracycline chlorhydrate. Anglers' catches, between June 1997 and September 1998, comprised trout aged 1+ to 7+ , but most (90% +) were 2+ to 3+ or 4+ , with the majority at 2+ and 3+. There was no significant difference in the size for a given age between marked and unmarked angled trout. The contribution of stocked fish in anglers' catches was around 22% for the 1995 cohort. The contribution of stocking (cohorts 1994 to 1995–1996) to the 1998 catches was around 23% (95% confidence limits: 19–27%). The estimated recapture rate was three to four trout per 1000 alevins stocked for the 1995 cohort. The major contribution (78%) of natural recruitment to anglers' catches suggests that the fishery management based on natural recruitment is still realistic in this part of River Doubs.
Reduction of a native fish fauna by alien species: an example from Brazilian freshwater tropical lakes
Authors: Latini A. O. , Petrere M. 
Published: December 2004

AbstractThe consequences of introducing Cichla cf. monoculus Spix & Agassiz, Astronotus ocellatus (Agassiz) and Pygocentrus nattereri Kner into lakes in the River Doce basin, Brazil, on richness, diversity and efficiency of aquatic macrophytes as natural refugia to native fishes was investigated. Samples were taken from lakes with and without alien fishes in areas with and without aquatic macrophytes. The presence of alien fishes reduced richness and diversity of the native fish community. The refugia function, which could be attributed to the clustering of aquatic macrophytes, does not exist in these lakes probably because the alien fishes exploit such habitats for reproduction. Since introductions threaten the native fish diversity of the region, studies on regional dispersion and factors that minimise the spread of alien fishes are needed.
Allozyme diversity in Australian rainbow trout, Oncorhynchus mykiss
Authors: Farrington L. W. , Austin C. M. , Burridge C. P. , Gooley G. J. , Ingram B. A. , Talbot B. 
Published: December 2004

AbstractRainbow trout, Oncorhynchus mykiss (Walbaum), were first introduced into Australia over 100 years ago, and forms the basis of important recreational inland fisheries and an aquaculture industry in south‐eastern Australia. This paper investigates the genetic variation within and between samples of Australian rainbow trout using allozyme electrophoresis. The levels of genetic diversity within Australia do not show marked differences from those observed in hatchery and wild populations from throughout North America, New Zealand and South Africa, but there is evidence for the loss of some rare alleles during translocation from California to Australia via New Zealand. No appreciable difference in genetic diversity was apparent between hatchery and self‐sustaining wild populations of rainbow trout from mainland Australia. However, significant differences in allelic frequencies were observed, with consistent genetic differences between Victorian and New South Wales samples most likely reflecting state‐based hatchery and stocking policies.
The influence of seasonal environmental changes on ontogenetic migrations of the squid Loligo gahi on the Falkland shelf
Authors: Arkhipkin A. I. , Grzebielec R. , Sirota A. M. , Remeslo A. V. , Polishchuk I. A. , Middleton D. A. J. 
Published: December 2004

AbstractThe Patagonian longfin squid Loligo gahi undertakes horizontal ontogenetic migrations on the Falkland shelf: juveniles move from spawning grounds located in shallow, inshore waters (20–50 m depths) to feeding grounds near the shelf edge (200–350 m depths). Immature squid feed and grow in these offshore feeding grounds and, upon maturation, migrate back to inshore waters to spawn. The possible influence of environmental factors on L. gahi migrations was investigated using data from oceanographic transects, crossing the region of known L. gahi occurrence. They were made from the inshore waters of East Falkland eastwards to depths of 1250 m on a monthly basis from 1999 to 2001. Four main water types were found in the region: Shelf, Sub‐Antarctic Superficial and Antarctic Intermediate water masses, and Transient Zone waters. The inshore spawning grounds occur in the Shelf Water mass, whereas the feeding squid (medium‐sized immature and maturing individuals) were associated with the Transient Zone. The 5.5°C isotherm appeared to mark the limit of squid distribution into deeper waters in all seasons. Seasonal changes in water mass characteristics and location were found to be important for seasonal changes in L. gahi migrations on the Falkland shelf.
Effect of temperature, age class, and growth on induction of aestivation in Japanese sandeel (Ammodytes personatus) in Ise Bay, central Japan
Authors: Tomiyama Minoru , Yanagibashi Shigeaki 
Published: December 2004

AbstractWe investigated the effects of temperature, age class, and growth on induction of aestivation in the Japanese sandeel (Ammodytes personatus) by means of rearing experiments and field surveys in Ise Bay, central Japan. Acoustic surveys and sampling of shoaling and aestivating sandeels indicated that the sandeels completed aestivation when the water temperature increased to 17–20°C. A rearing experiment showed that the mortality of sandeels reared without sand was greater than it was with sand, under replete feeding conditions. In a non‐aestivation rearing experiment without sand, the condition factor of the sandeels decreased when water temperatures exceeded 20°C, although they were fed to repletion. These results suggest that aestivation is induced by rising seawater temperature and plays an important role in energy conservation. The age‐1 group tended to start aestivation earlier than the age‐0 group in the field. Within the age‐0 group, larger sandeels tended to enter aestivation earlier. These observations indicate that fat reserves are an important cue to start aestivation.
Optimum temperature and food‐limited growth of larval Atlantic cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) on Georges Bank
Authors: Buckley Lawrence J. , Caldarone Elaine M. , Lough R. Gregory 
Published: December 2004

AbstractWe estimated recent growth of Atlantic cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) larvae collected on the southern flank of Georges Bank in May 1992–94 from the ratio of RNA to DNA (R/D) and water temperature. Growth of both species increased with water temperature to about 7°C and then decreased. The highest growth rates were observed in May 1993 at water temperatures around 7°C. These data confirm an earlier observation of comparable temperature optima for growth of Atlantic cod and haddock larvae in the north‐west Atlantic. Comparisons of field growth rates and temperature optima with data for larvae cultured at high temperatures and prey densities in the laboratory suggest that growth may have been food‐limited at higher temperatures on Georges Bank. Given that 7°C is the long‐term mean water temperature on the southern flank in May and that climate models predict a possible 2–4°C rise in water temperatures for the western North Atlantic, our findings point to a possible adverse effect of global warming on Atlantic cod and haddock.
Effects of essential fatty acids and N and P‐limited algae on the growth rate of tropical cladocerans
Authors: Ferrão‐Filho Aloysio S. , Fileto Cláudia , Lopes Norberto P. , Arcifa Marlene S. 
Published: December 2004

SUMMARY 1. In this study, the effects of nutrient (N and P) deficiency and the importance of essential polyunsaturated fatty acids (PUFA) [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] to tropical cladocerans, growth and reproduction were determined in a growth bioassay.2. The animals were fed N/P‐sufficient, N‐deficient and P‐deficient algae, and also N and P‐deficient algae supplemented with fish oil emulsions rich in EPA and DHA.3. Cladocerans showed different responses to nutrient‐deficient algae and also to supplements of fish oil emulsions. Moina micrura was most sensitive to P‐deficient alga and, surprisingly, grew better and produced more eggs in N‐deficient alga than in N/P sufficient alga. Ceriodaphnia cornuta was less sensitive, growing well in both N and P‐deficient algae. This species, however, had a lower clutch size in N‐deficient alga. On the other hand, Daphnia gessneri was the most sensitive to mineral limitation, showing decreased growth and clutch size in both nutrient‐deficient algae.4. The PUFA supplements to nutrient‐deficient algae increased growth rates only for M. micrura and C. cornuta, suggesting that these fatty acids are important food requirements for these species.
Connectivity and cladoceran species richness in a metacommunity of shallow lakes
Authors: Cottenie Karl , De Meester Luc 
Published: December 2004

SUMMARY 1. The shallow ponds of the nature reserve ‘De Maten’ form a metacommunity, in which individual ponds are highly interconnected via a system of overflows and rivulets. This study reports on the relations between cladoceran species richness and (a) connectivity patterns and (b) local environmental variables.2. No relation was found between local species richness and three connectivity variables or dispersal pathways.3. Spatial configuration was related to richness, but was confounded by environmental variables for 2 of 3 years. In those 2 years, there was a significant linear relation between Secchi disc depth and species richness, suggesting an important impact of the clearwater/turbid state alternative equilibria in shallow lakes in determining cladoceran richness. Only in the year in which environmental variables were unimportant did connectivity between the ponds influence species richness.4. These results suggest that local environmental variables related to the clearwater/turbid state alternative equilibria in shallow lakes are important in determining cladoceran species richness. Connectivity and dispersal of individuals between the different ponds only act secondarily by increasing the general species richness within a pond through dispersal from ponds with different environmental conditions.
Occurrence of mixotrophic flagellates in relation to bacterioplankton production, light regime and availability of inorganic nutrients in unproductive lakes with differing humic contents
Authors: Bergström Ann‐Kristin , Jansson Mats , Drakare Stina , Blomqvist Peter 
Published: December 2004

SUMMARY1. Field data from five unproductive Swedish lakes were used to investigate the occurrence of mixotrophic flagellates in relation to bacterioplankton, autotrophic phytoplankton, heterotrophic flagellates and abiotic environmental factors. Three different sources of data were used: (i) a 3‐year study (1995–97) of the humic Lake Örträsket, (ii) seasonal measurements from five lakes with widely varying dissolved organic carbon (DOC) concentrations, and (iii) whole lake enrichment experiments with inorganic nutrients and organic carbon.2. Mixotrophic flagellates usually dominated over autotrophic phytoplankton in Lake Örträsket in early summer, when both bacterial production and light levels were high. Comparative data from the five lakes demonstrated that the ratio between the biomasses of mixotrophic flagellates and autotrophic phytoplankton (the M/A‐ratio) was positively correlated to bacterioplankton production, but not to the light regime. Whole lake carbon addition (white sugar) increased bacterial biomass, and production, reduced the biomass of autotrophs by a factor of 16, and increased the M/A‐ratio from 0.03 to 3.4. Collectively, the results indicate that the dominance of mixotrophs among phytoplankton was positively related to bacterioplankton production.3. Whole lake fertilisation with nitrogen (N) and phosphorus (P) demonstrated that the obligate autotrophic phytoplankton was limited by N. N‐addition increased the biomass of the autotrophic phytoplankton but had no effect on mixotrophic flagellates or bacteria, and the M/A‐ratio decreased from 1.2 to 0.6 after N‐enrichment. Therefore, we suggest that bacteria under natural conditions, by utilising allochthonous DOC as an energy and carbon source, are able to outcompete autotrophs for available inorganic nutrients. Consequently, mixotrophic flagellates can become the dominant phytoplankters when phagotrophy permits them to use nutrients stored in bacterial biomass.4. In Lake Örträsket, the biomass of mixotrophs was usually higher than the biomass of heterotrophs during the summer. This dominance could not be explained by higher grazing rates among the mixotrophs. Instead, ratios between mixotrophic and heterotrophic biomass (the M/H‐ratio) were positively related to light availability. Therefore, we suggest that photosynthesis can enable mixotrophic flagellates to outcompete heterotrophic flagellates.
Increase in photosynthetic efficiency as a strategy of planktonic organisms exploiting deep lake layers
Authors: Modenutti Beatriz , Balseiro Esteban , Callieri Cristiana , Queimaliños Claudia , Bertoni Roberto 
Published: December 2004

Summary1. The photosynthetic efficiencies of the mixotrophic ciliate Ophrydium naumanni and the autotrophic dinoflagellate Gymnodinium paradoxum were investigated using laboratory and field experiments in Lake Moreno Oeste (41°5′S and 71°33′W, 758 m a.s.l.), in the Nahuel Huapi System (North Patagonia, Argentina).2. The effect of different underwater light intensities on net primary production (NPP) was assessed during one summer. Additionally, laboratory experiments were carried out to obtain photosynthesis‐irradiance response curves for each species.3. Ophrydium naumanni and G. paradoxum dominated the metalimnetic (30 m depth) deep chlorophyll maximum (DCM) in the lake.4. Despite these deep higher abundances, the cell‐specific production of both species was higher at 10 m than at 30 m (DCM) depth. In addition, at 5 m depth, NPP was reduced by PAR + UV‐A radiation.5. Both species exhibited a positive NPP at very low irradiance but the mixotrophic ciliate was more efficient in exploiting the DCM irradiance level both in situ and at comparable light intensities in laboratory experiments. Light acclimatised O. naumanni showed a higher NPP at lower irradiances and photoinhibition at medium and high irradiances.6. Under the strong wind‐driven turbulence commonly found in Patagonian lakes, organisms cannot select their position in the epilimnetic water column and will be dragged to potentially harmful UV radiation levels. Thus, metalimnetic DCM colonisation by these two species represents a tradeoff between higher survival and lower cell‐specific NPP.
Root anchorage of saplings and cuttings of woody pioneer species in a riparian environment
Authors: Karrenberg S. , Blaser S. , Kollmann J. , Speck T. , Edwards P. J. 
Published: December 2004

Summary

The root anchorage ability of saplings and vegetative propagules may be decisive for persistence of woody pioneers in the highly disturbed habitat of floodplains.
Vertical uprooting resistance was investigated in saplings of three floodplain pioneers of central Europe, Alnus incana, Populus nigra and Salix elaeagnos, at the near‐natural River Tagliamento, north‐east Italy. Uprooting resistance of planted cuttings of P. nigra and S. elaeagnos was studied at this site and in an experimental garden.
Uprooting resistance was lowest in saplings of A. incana, intermediate in P. nigra, and highest in S. elaeagnos. For cuttings, differences in uprooting resistance between species were evident only under floodplain conditions, where resistance was higher in P. nigra than in S. elaeagnos. This difference was related to better growth in P. nigra.
The anchorage ability of saplings may be one factor influencing the longitudinal and transverse zonation of species in floodplains, as S. elaeagnos is restricted to highly disturbed sites close to the main channel, whereas A. incana and P. nigra occupy more stabilized habitats. For vegetative propagules, in contrast, regeneration ability may be more important than uprooting resistance.
Temperature and the chemical composition of poikilothermic organisms
Authors: Woods H. A. , Makino W. , Cotner J. B. , Hobbie S. E. , Harrison J. F. , Acharya K. , Elser J. J. 
Published: December 2004

SummaryTemperature strongly affects virtually all biological rate processes, including many central to organismal fitness such as growth rate. A second factor related to growth rate is organismal chemical composition, especially C : N : P stoichiometry. This association arises because high rates of growth require disproportionate investment in N‐ and P‐rich biosynthetic cellular structures. Here the extent to which these factors interact is examined – does acclimation temperature systematically affect organismal chemical composition?A literature survey indicates that cold‐acclimated poikilotherms contain on average 30–50% more nitrogen [N], phosphorus [P], protein and RNA than warm‐exposed conspecifics. The primary exception was bacteria, which showed increases in RNA content but no change in protein content at cold temperatures.Two processes – changes in nutrient content (or concentration) and in organism size – contribute to the overall result. Although qualitatively distinct, both kinds of change lead to increased total catalytic capacity in cold‐exposed organisms.Temperature‐driven shifts in nutrient content of organisms are likely to resonate in diverse ecological patterns and processes, including latitudinal and altitudinal patterns of nutrient content, foraging decisions by organisms living in strong temperature gradients, and patterns of biodiversity.
Tamo selectively modulates nuclear import in Drosophila
Authors: Minakhina Svetlana , Yang Jun , Steward Ruth 
Published: December 2004

AbstractBackground: The NF‐κB/Rel pathway functions in the establishment of dorsal‐ventral polarity and in the innate humoral and cellular immune response in Drosophila. An important aspect of all NF‐κB/Rel pathways is the translocation of the Rel proteins from the cytoplasm to the nucleus, where they function as transcription factors.Results: We have identified a new protein, Tamo, which binds to Drosophila Rel protein Dorsal, but not to Dorsal lacking the nuclear localization sequence. Tamo does not bind to the other Drosophila Rel proteins, Dif and Relish. The Tamo‐Dorsal complex forms in the cytoplasm and Tamo also interacts with a cytoplasmically orientated nucleoporin. In addition Tamo binds the Ras family small GTPase, Ran. Tamo functions during oogenesis and, based on phenotypic analysis, controls the levels of nuclear Dorsal in early embryos. It further regulates the accumulation of Dorsal in the nucleus after immune challenge.Conclusions: Tamo has an essential function during oogenesis. Tamo interacts with Dorsal and proteins that are part of the nuclear import machinery. We propose that tamo modulates the levels of import of Dorsal and other proteins.
Alleles of the proximal promoter of BAT1, a putative anti‐inflammatory gene adjacent to the TNF cluster, reduce transcription on a disease‐associated MHC haplotype
Authors: Wong Agnes M.‐L. , Allcock Richard J. N. , Cheong Karey Y. M. , Christiansen Frank T. , Price Patricia 
Published: December 2004

AbstractBackground: BAT1 belongs to the DEAD‐box family of proteins, and is encoded in the central region of the MHC, a region containing genes affecting immunopathological disorders including Type 1 diabetes. We showed that BAT1 can reduce inflammatory cytokine production, supporting its candidacy as a disease gene. Here we examined the proximal promoter region of BAT1.Results: Ten single nucleotide polymorphisms were identified in ≈1.4 kb of sequence, defining at least seven alleles. Sections of the BAT1 promoter region were amplified from cells homozygous for the MHC haplotypes associated with susceptibility (HLA‐A1, B8, DR3; 8.1 haplotype) and resistance (HLA‐A3, B7, DR15; 7.1 haplotype) to diabetes and cloned into a promoter‐less luciferase‐encoding plasmid. Jurkat cells transiently transfected with fragments from the 8.1 haplotype exhibited a lower luciferase activity than those transfected with fragments from the 7.1 haplotype, indicating reduced transcription. The effect was clearest with the 520 bp immediately upstream of the transcriptional start site. Electrophoretic mobility shift assays using oligonucleotides spanning polymorphic sites within the 520 bp (proximal) promoter fragment showed haplotype‐specific binding of nuclear proteins.Conclusions: In view of the anti‐inflammatory role of BAT1, reduced production on a disease‐associated haplotype constitutes a novel and self‐consistent model for the effect of central MHC genes on disease.
A SWI2/SNF2‐type ATPase/helicase protein, mDomino, interacts with myeloid zinc finger protein 2A (MZF‐2A) to regulate its transcriptional activity
Authors: Ogawa Hironori , Ueda Takeshi , Aoyama Tomohisa , Aronheim Ami , Nagata Shigekazu , Fukunaga Rikiro 
Published: December 2004

AbstractBackground: The myeloid zinc finger protein 2A (MZF‐2A) is a Krüppel‐type C2H2 zinc finger transcription factor expressed in myeloid cells and involved in the growth, differentiation and tumorigenesis of myeloid progenitors. Previously we identified a 180 amino acid domain in MZF‐2A which is responsible for the transcriptional activation of MZF‐2A. To understand the mechanism of the MZF‐2A‐dependent transcriptional activation, we screened for molecules that interact with the transactivation domain (TAD) of MZF‐2A.Results: By using the yeast Ras recruitment two‐hybrid screening, we identified a novel SWI2/SNF2‐related protein, termed mammalian Domino (mDomino), as an MZF‐2A‐binding partner. The mDomino protein, which shows a marked similarity to the Drosophila Domino protein, contains a SWI2/SNF2‐type ATPase/helicase domain, a SANT domain, and a glutamine‐rich (Q‐rich) domain. The C‐terminal Q‐rich domain of mDomino physically associates with the TAD of MZF‐2A in mammalian cells as well as in yeast. Expression of the mDomino Q‐rich domain, together with MZF‐2A in myeloid LGM‐1 cells, enhanced the MZF‐2A‐mediated activation of a reporter gene.Conclusions: These results strongly suggest that an ATP‐dependent chromatin‐remodelling complex containing mDomino interacts with MZF‐2A to regulate gene expression in myeloid cells.