bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deposit Feeding and Sediment:
Authors: Amon Rainer M. W. , Herndl Gerhard J. 
Published: May 2008

Abstract. The feeding of the epibenthic deposit‐feeder Holothuria tubulosa GMELIN and its influence on sediment metabolism was investigated from February 1988 to February 1989. Water samples, specimens of H. tubulosa, and samples of freshly egested feces were taken by SCUBA diving in a 5 m deep seagrass bed at the Island of Ischia in the Gulf of Naples (Italy). Particulate organic carbon (POC), particulate organic nitrogen (PON), total particulate carbohydrates (PCHO), and bacterial biomass exhibited higher values in the foregut than in the surrounding sediment. Even the freshly egested feces were richer in the organic components than the sediment. The percentage of growing bacterial cells increased from 4.1 % in the sediment to 12.2 % in the foregut and declined to 11.6 % in the hindgut and 6.2 % in freshly egested feces.On an annual average, absorption efficiency was highest for bacteria (x = 71%); for PON we calculated a mean absorption efficiency of 20.9%, for PCHO 19.5%. It was estimated that bacterial biomass supplied between 4 and 25 % of the respiratory carbon demand of H. tubulosa. We present evidence that the feeding activity of H. tubulosa stabilizes the bacterial community in the sediment. Furthermore, our data indicate that H. tubulosa reacts quickly to changing conditions, such as sedimented phytoplankton blooms.
Fungal Invasion of Massive Corals
Authors: Raghukumar Chandralata , Raghukumar S. 
Published: May 2008

Abstract. Five species of corals from the Andaman Islands in the Bay of Bengal (Indian Ocean) have been regularly found to have single or multiple necrotic patches. The occurrence of such corals with necrotic patches varied from 10–50% in the field. Sections revealed a septate dark brown mycelial fungus on the surface and subsurface of the dead patches in five coral species. The fungus was isolated in culture and identified as Scolecobasidium sp.The fungus formed a distinct dense brown to black zone of 0.5‐1.5 cm width immediately below the surface of the corals. In terms of biomass, the fungus was estimated to contribute 3–5 mg cm ‐3 of coral skeleton.
Detritus Rolling Down a Vertical Cliff of the Ligurian Sea (Italy): The Écological Role in Hard Bottom Communities
Authors: Bavestrello Giorgio , Cattaneo‐Vietti Riccardo , Danovaro Roberto , Fabiano Mauro 
Published: May 2008

Abstract. The detritus rolling down a vertical cliff was studied at Portofino Promontory (Ligurian Sea, Italy) at 16 m depth (January 1988‐ January 1989). The large amount of collected sediment is mainly due to the position of the traps; they collected not only the sedimenting material, but also the detritus rolling down along the cliff. The amount of sediment matter is 7 times greater in winter than in summer, showing a good correlation with rough seas and rain that cause a “mechanical cleaning” of animal and plant debris (Sérpulid tubes, shells, exuvias. leaves) along the cliff.The Total Suspended Matter (TSM) in the water column shows maximum values in March and September. The organic fraction has an average concentration of 0.81 mg 1‐l. The phytoplanktonic biomass, measured as Chi a, shows an annual cycle with a peak in spring (1–2.7μg·l‐1). while in other periods of the year the value is about 0.3‐0.5 μg·1‐1. A significant relationship was found between organic detritus in the collected sédiments and the Chi a in the water column. The great influence of the rocky wall detritus on the normal trend of the TSM in the coastal water column is pointed out.
Ecology of Vibrios in the Oliveri‐Tindari Lagoon (Messina), Two‐Year Study
Authors: Zaccone Renata , Crisafi Ermanno , Genovese Lucrezia 
Published: May 2008

Abstract. A two‐year ecological study in the Oliveri‐Tindari (Messina) brackish water ponds evaluated the quantitative and qualitative distribution of Vibrio species in relation to the physicochemical conditions of the ponds.The evaluation of 204 samples shows a general relationship between the halophilic vibrios and water temperature. In particular this relationship is stronger for the Vibrio fraction able to grow at 37°C, i. e., those species related to human infections. On the other hand, the halophilic vibrios show no relation with the index of fecal contamination.The ecology of V. parahaemolyticus is discussed in relation to the salinity of Marinello pond.The distribution of V. cholerae non O1, isolated from all ponds, shows that this microorganism can be considered as autochthonous in coastal environments.
Quantitative Benthic Community Structure in Blanca Bay and Its Relationship With Organic Enrichment*
Authors: Elias Rodolfo 
Published: May 2008

Abstract. A two year benthic sampling program of a 2000 km2 area, covering 22 stations, showed a dominance of deposit‐feeding polychaetes. The quantitative structure of the three infaunal assemblages was related to a salinity gradient: the inner and outer regions were inhabited by, respectively, mixohaline and euhaline associations, both quantitatively related to granulometric facies of sediment. Species diversity was very low in the inner region, although abundance of opportunistic species was high. In the outer region, abundance and diversity were more stable, with an increasing number of species.A comparison of species number and abundance with Species‐Abundance‐Biomass curves from enriched environments showed that the inner region of Bianca Bay may be considered as an organically enriched environment. Scoloplos, a species associated with organic enrichment, and dense terebellid belts were present in great abundances in front of sewage outflows. The spatial distribution of heterotrophic bacteria and the bivalves Corbula and Nucula also followed this pattern.
La Réponse aux Couleurs chez Dicentrarchus labrax (Moronidae), Placé en Situation de «Self‐feeding», et de Choix Multiple: Response to Colours in Dicentrarchus labrax (Moronidae), in a Self‐Feeding and Multiple Choice Condition
Authors: Kentouri M. , Anthouard M. , Divanach P. 
Published: May 2008

Abstract. A population of sea‐bass, housed under semi‐natural and self‐feeding conditions, was presented with six different coloured levers. Their choices tended to favour more colour‐contrasted levers and were greatly affected by environmental conditions such as stress factors, circadian period, season, and thermal fluctuations. A correlation was observed between increases in instrumental acitivity, indicating an increase in energetic requirements, and a widening of choices in the exploitation of the coloured levers.Consequences of these behaviours were considered in relation to predator pressure that the fish imposes on potential prey populations in the natural environment, and in relation to the initiation of feeding activity when the fish are maintained in captivity and under self‐feeding conditions.
Community Structure of Soft‐Bottom Macrobenthos of the Newport Submarine Canyon, California
Authors: Maurer D. , Robertson G. , Gerlinger T. 
Published: May 2008

Abstract. The hypothesis that benthic community structure of soft‐bottom macrobenthos does not change throughout the Newport Submarine Canyon, California was tested with a set of quantitative Van Veen (0.1 m2) samples down the canyon axis. There was a marked break in community structure between Station C4 (187 m) and Station C5 (324 m). Comparison of the present study with work conducted earlier indicates that mean number of species, abundance, and biomass were not significantly different between 1962 and 1978. Within the canyon, species diversity was high compared to 12 other southern California canyons. This difference was mainly due to sampling effort and the inactive nature of the Newport Canyon.SummaryOver 500 species are identified from Newport Canyon, California from 1978 to 1990. The diversity of soft‐bottom macrobenthos in shallow to intermediate depths of Newport Canyon is much higher than in other southern California canyons (Hartman, 1963). This difference is mainly due to sampling effort and the inactive nature of Newport Canyon which facilitates the maturation of soft‐bottom communities; in contrast to active canyons which through turbidity currents frequently disrupt the water‐sediment interface. Conditions within Newport Canyon have been stable for benthic community structure for at least 16 years and probably closer to 25 years. The hypothesis examined here shows that community structure is not homogeneous with depth along its axis, but has a marked break between 187 m and 324 m. Finally, we are now in a position to examine hypotheses concerning the effects of an ocean outfall on benthic community structure between the shelf and the canyon.
Stochastic Events and Dynamics of a Mangrove Root Epifaunal Community
Authors: Bingham B. L. , Young C. M. 
Published: May 2008

Abstract. Submerged roots of red mangroves (Rhizophora mangle) in the Florida Keys were photographed at 1– or 2‐month intervals for 38 months to measure population dynamics of the epifaunal invertebrate species. Photographs were analysed for species composition and abundance and information on life spans, persistence, mortality, and seasonality. Larval recruitment to artificial surfaces was used to assess reproductive seasonality. As a measure of stability, populations were tested for narrow stochastic boundedness.In contrast to reports for a tropical mangrove root community, the Florida Keys root community showed enormous variability despite being dominated by long‐lived species with low, largely non‐seasonal recruitment. Species composition on individual roots changed dramatically on short time scales. Populations of the major species were not narrowly bounded on most roots and there was little evidence for a closely regulated community.Variability of this community related to the frequency and intensity of stochastic perturbations. Physical disturbance due to strong tidal Rows appeared to be the most important structuring process. Species‐specific predation and fragmentation of sponges were also important. These features contribute to the instability of the community by producing dramatic fluctuations in species abundances and preventing competitive processes from producing a more stable, equilibrium community. Temporal measurement scale was an additional important consideration in this habitat. Structuring processes occurred on very short time scales (1–2 months) and analysis on longer time scales gave inaccurate impressions of community dynamics.
Contribution of Sponge Spicules to the Composition of Biogenic Silica in the Ligurian Sea
Authors: Bavestrello Giorgio , Cattaneo‐Vietti Riccardo , Cerrano Carlo , Cerutti Stefania , Sará Michele 
Published: May 2008

Abstract. The importance of sponge spicules in the turnover of biogenic silica (BSi) in the detritic bottoms of the Eastern Ligurian Riviera was evaluated by studying sediment cores and the detrital matter collected by a trap over a one year period.This study made evident that: i) Sponge spicules represent the main component of the BSi both in the sediments and in the trapped matter; ii) A correlation exists between the sponge biomass present on the overhanging cliff and the amount of sponge spicules found in the sediment below; iii) Inside the sediments, a superficial layer (10 cm deep) characterized by intensive silica dissolution processes can be observed; and iv) The amount of spicules collected using the trap is not constant throughout the year, but shows a characteristic trend with low values in spring and summer and high values in autumn and winter.
Some Aspects of Fluorite and Vaterite Precipitation in Marine Environments*
Authors: Wittmann Karl J. , Ariani Antonio P. 
Published: May 2008

Abstract. Mysid shrimps of the genus Schistornysis precipitate either fluorite (CaF2; S. spiritus) or vaterite (CaCO3; S. assimilis) for the formation of static bodies (statoliths). In S. assirnilis, 2.44 μg calcium and 3.66 μg carbonate are precipitated for each statolith. This corresponds to 69 mg or 30 mg ambient water, respectively, using the ion content of seawater for stoichiometrical comparison. Concentmtion factors of calcium or carbonate in relation to equivalent amounts of ambient water in the statocyst cavity are 760 or 3100, respectively. In S. spiritus, 3.79 μg calcium and 3.60 μg fluoride are precipitated. This corresponds to 9.3 mg or 2788 mg ambient water, respectively. Concentration factors with respect to statocyst water mass are 610 or 183.000. respectively. Ile high fluoride accumulation for the formation of statoliths alone contributes to a fluoride content of 4500 ppm with respect to body dry weightA minimum estimate for the role of mysids in the global fluoride cycle suggests that at least 62,000 tons of fluoride are bound in mysid statoliths. Due to rapid turnover of about seven days, mysid fluorite statoliths are a crucial factor by contributing to a turnover of at most 570,000 years for overall fluoride in the oceanic system.
Annual Variation of Benthic Nutrient Fluxes in Shallow Coastal Waters (Gulf of Trieste, Northern Adriatic Sea)
Authors: Bertuzzi Alessandra , Faganeli Jadran , Bflmbati Antonio 
Published: May 2008

Abstract. Benthic fluxes of dissolved N. Si and P nutrients, alkalinity, dissolved inorganic C (DIC), and O2 from sediments in the Gulf of Trieste (northern Adriatic, Italy) were measured monthly for 16 months, using laboratory incubated flux chambers at in siru temperatures in the dark.The annual average fluxes were: 02 = ‐19.3 ± 8.2, DIC = 13.7 ± 9.6, NO3 = ‐0.04 ± 0.16, NH4 = 0.3 ± 0.4. PO4= 4.001 ± 0.01, Si = 0.9 ± 0.1 mmol m‐2 d‐1, with strong temporal fluctuations. The highest effluxes of all nutrients and DIC were observed in the summer. Small effluxes of DIC and NH4 and influxes of Si and PO4 were observed in late winter. Only NH4 (ca. 50%) and Si (ca. 70%) fluxes were significantly correlated with temperature. This correlation suggests that the rate of downward input and the quality of sedimented organic matter (autochthonous and allochthonous) were superimposed on the temperature fluctuations. High DIC, NH4 and Si effluxes observed in May 1993 during low temperature were due to the degradation of sedimentary organic matter produced by an early spring bloom of benthic microalgae which occurred about 6 weeks earlies while the autumn phytoplankton bloom was simultaneously reflected in enhanced benthic fluxes due to higher temperature.The role of benthic biological advection in this transport across the sediment‐water interface, evaluated by comparison between measured benthic and calculated diffusive fluxes from nutrient pore water concentrations, was of minor importance. This is probably due to low infaunal activity throughout the year it was localized mostly in the narrow surficial layer. The annual average diffusive fluxes of NH4 and PO4 were higher than those measured, probably due to the presence of nitrificationdenitrifi‐cation processes and redox‐dependent chemical reactions at the oxic sediment‐water interface, respectively. Only during bottom‐water hypoxia in September 1993 did strong PO4 effluxes prevail. Calculations based on the Redfield stoichiometry of oxic decomposition of organic N to NH4 and NO3, and differences between diffusive and measured NH4 fluxes showed that denitrifkation averaged 0.8 mmol m‐2 d‐1. Significant correlations between NH4 and PO4 DIC and Si, and NH4 and Si fluxes suggested their parallel regeneration and utilization at the sediment‐water interface.The nutrient fluxes observed were not significantly linked to O2 consumption, suggesting also that anaerobic oxidation processes were important at the sediment‐water interface in the gulf. The N, P and Si nutriqnts released from sediment pore waters are probably utilized in benthic microalgal and bottorn‐hater primary production. This indicates that pelagic and benthic communities in the central part of the Gulf of Trieste function relatively independently of each other.
The Effects of Reduced Oxygen Content on Predation and Siphon Cropping by the Brown Shrimp, Crangon crangon
Authors: Sandberg Eva , Tallqvist Minna , Bonsdorff Erik 
Published: May 2008

Abstract. Aquarium experiments were performed to test for critical oxygen levels in relation to the predation efficiency of C. crangon. Short‐term (60 h) experiments where done in normoxia (> 95%). 50, 40.30, and 20% oxygen saturation with the amphipod Bathyporeiapilosa as prey. A significantly reduced predation rate was detected at 30% oxygen. Sublethal effects of C. crangon on adult Macoma balthica (mainly by siphon cropping) were studied by measuring the condition of the clams (morphometric, somatic, and biochemical). To test for these effects experiments were conducted under normoxia and moderate hypoxia (40% oxygen); Condition and siphon indices revealed no change in condition after a 3‐week exposure to moderate hypoxia, while a significant reduction in the condition of adult clams was found in both normoxia and hypoxia when subjected to siphon cropping by C. crangon. No enhanced siphon cropping could be detected due to hypoxia.The results indicate that C. crangon is able to maintain its predatory role until a level of 30% oxygen in short‐term exposure. After a 20% oxygen level, however, the abiotic stress alters the functional role of C. crangon as a predator, indicating a threshold of 20–302 oxygen for the normal functioning of the predator‐prey food webs.
Biomass Size Spectra of Near‐Shore Shallow‐Water Benthic Communities in the Gulf of Gdańsk Southern Baltic Sea
Authors: Drgas Aleksander , Radziejewska Teresa , Warzocha Jan 
Published: May 2008

SummaryThe concept of size spectra, developed by Sheldon & Parsons 1967 and Sheldon et al. 1972, seeks to describe community structure by evoking the distribution of biomass over a sequence of equal intervals of the logarithm of body size. In this study, biomass size spectra were prepared for benthic macro‐ and meiobenthos communities at 5 stations, differing in their sediment characteristics, located in the shallow, coastal area of the Gulf of Gdańsk Southern Baltic Sea. The purpose of this study was to determine whether the community spectra would allow distinct separation of ecological categories of the benthos and whether habitat differences between stations would significantly affect benthic size spectra.Benthic biomass at the stations sampled depended mainly on nematodes and oligochaetes among the meiobenthos and on hydrobiid snails and M. edulis among the macrobenthos. Regardless of habitat, size spectra peaked initially at the meiofaunal range weight class 25 1. 19–501.19 ng C, identical to that reported in other studies. The separation between meio‐ and macrobenthic peaks, however, was not as pronounced as that found in other studies. Normalized size spectra demonstrated that most of the variations in the spectra between stations was introduced by macrobenthos, which differed between the coarse‐ and fine‐grained sediments. Nonetheless, those differences were not strong enough to significantly affect the spectra. In consequence, the benthic biomass spectra of all the stations were found to conform to a common pattern and could be represented by a single, average spectrum.
Influence of Bacterial Exopolymers, Conspecific Adult Extract and Salinity on the Cyprid Metamorphosis of Balanus amphitrite Cirripedia: Thoracica
Authors: Anil Arga C. , Khandeparkar Rakhee D. S. 
Published: May 2008

Abstract. The influence of bacterial exopolymers and conspecific adult extract of Balanus amphitrite on metamorphosis of cyprid larvae at different salinities has been evaluated through laboratory assay. The bacterial exopolymers epm extracted from Pseudomonas, Acinetobacter and Enterobacteriaceae strains, isolated from the shell surface of Balanus amphitrite, were examined for their influence on metamorphosis, both individually and in combination with conspecific adult extract at 15, 25, 35 and 45% salinities. The epm extracted from the pool of these three strains mixed culture was also tested similarly.The influence of epm varied with the strain of bacteria and salinity. The surface condition and time interval significantly influenced the metamorphosis rate. The interaction between these two variables, however, did not change in any combination, irrespective of the bacterial strain used. The Pseudomonas epm promoted metamorphosis at 15%, but was inhibitory at 45%. The Acinetobacter epm induced metamorphosis to a level of 71 ± 15% at 15%. No such metamorphosis promotion was observed with the epm of this strain at higher salinities and the influence was less than the conspecific adult extract. The epm of Enterobacteriaceae and mixed culture epm did not promote metamorphosis. There was no appreciable change in the metamorphic rate in the control conditions at 25%, 35% and 45% salinities and the rate was much lower than that obtained with conspecific adult extract. At 15%, however, the influence of adult extract was closer to that of the control condition. This shows that even in the absence of any attractant, the settlement intensity is positively influenced at mid‐salinity of the barnacles' natural distributional range.
Development of an instrument to measure the clinical learning environment in diagnostic radiology
Authors: Bloomfield L , Subramaniam R 
Published: May 2008

SummaryA clinical learning environment survey instrument was developed that provided insights into diagnostic radiology trainees’ perceptions of the culture and context of the hospital‐based training programme. The survey was completed by trainees allocated to 37 important training hospitals in Australia, New Zealand and Singapore in 2006. The main findings were that most obvious strengths of the diagnostic radiology programme are the wide variety of work‐based learning opportunities and the social atmosphere. These were well regarded in all training sites. Work overload was seen as a significant problem in most hospitals and will probably remain a challenge. The areas that are most likely to repay efforts to bring about change are supervision and feedback. The study provides baseline data against which the influence of changes to the training programme may be evaluated.
Fine‐needle trucut biopsy versus fine‐needle aspiration cytology with ultrasound guidance in the abdomen
Authors: O’Connell AM , Keeling F , Given M , Logan M , Lee MJ 
Published: May 2008

SummaryHistorically, fine‐needle aspiration cytology (FNAC) has varying sensitivity, specificity and accuracy in the diagnosis of abdominal lesions with a high insufficient sampling rate. We compared 20‐G fine‐needle trucut biopsy (FNTB) with FNAC results in the biopsy of solid abdominal tumours. A retrospective review of 171 (128× 20‐G FNTB and 43× FNAC) ultrasound‐guided biopsies of abdominal tumours on 157 patients (male : female 85:72, mean age 61.25 years) were carried out. One hundred and seventy‐one biopsies were carried out: liver 109, pancreas 19, lymph node 10, omentum 5, right iliac fossa mass 6, adrenal 6 and others 16. An average of 2.06 and 1.97 passes (range 1–4) were carried out per FNTB and FNAC, respectively. A definitive diagnosis was made in 122/128 biopsies (95.3%) and 32/43 biopsies (74.4%) for FNTB and FNAC, respectively. Diagnoses consisted of metastatic liver disease (74/171), pancreatic adenocarcinoma (10/171), lymphoma (8/171) and others (33/171) and benign (29/171). No significant complications occurred in either group. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 87, 100, 100, 50, 84.4 and 93.1, 100, 100, 60, 71.4 for FNTB and FNAC, respectively. A greater and more consistent positive diagnosis rate is yielded by 20‐G FNTB (95.3%) than FNAC (74.4%). The diagnostic accuracy of FNTB is 84.4% compared with 69.8% for FNAC. A greater insufficient sampling rate occurs with FNAC (25.6%) than with FNTB (4.7%). For abdominal biopsy, 20‐G FNTB needles have a much higher yield than FNAC with no increase in complications. FNTB is the preferred choice, particularly where cytological assistance at the time of biopsy is unavailable.