Foraging behavior and diet composition of Trimma caudomaculata and Trimma caesiura (Gobiidae) on coral reefs in Okinawa, Japan

The feeding habits of two small gobies, Trimma caudomaculata and T. caesiura, were surveyed on coral reefs in Okinawa, Japan. Both species actively exhibited foraging attempts beneath overhanging reef structures during the daytime, and fed on small animals, mainly copepods. Trimma caudomaculata formed feeding schools in water columns to swallow mainly Calanoida and Harpacticoida. Trimma caesiura stayed by themselves on the reef substratum and captured mainly Harpacticoida by taking short jumps into the water column. Diet compositions of these congeneric gobies may reflect differences in their foraging behaviors and use of microhabitats.     

Impact of West Nile Virus on American Crows in the Northeastern United States,and Its Relevance to Existing Monitoring Programs

We assessed the changes in abundance of American crows in the northeastern U.S. following the arrival of West Nile virus (WNV), with two aims. First, we determined the impact and spatial extent of the initial epizootic that began in New York City. Second, we examined whether two existing surveillance programs monitoring for WNV (data from 2000 New York State dead bird testing, and 2000 mosquito testing) accurately predicted the observed impact of the disease on crow populations as measured using data from the North American Christmas Bird Count. The rationale for this second aim was that the two WNV surveys were new and with unknown biases and sensitivity, while the Christmas Bird Count has existed for decades, providing monitoring before the arrival of WNV in North America and a long time series of data useful in gauging sensitivity. As a result, the Christmas Bird Count represents a good benchmark against which to compare the two new surveillance programs. Consistency among these three sources of information was low, suggesting that while dead bird and mosquito surveys can currently indicate the later stages of severe outbreaks, the ability to consistently detect early stages of outbreaks is questionable.     

Lipid extracts from different algal species:1H and13C-NMR spectroscopic studies as a new tool to screen differences in the composition of fatty acids,sterols and carotenoids

One- and two-dimensional¹H- and¹³C-NMR spectra of lipid extracts fromUlva rigida, Gracilaria longa, Fucus virsoides andCodium tomentosum collected in the northern Adriatic Sea allowed screening of the content of fatty acid chains, carotenoids, free and acylated cholesterol and chlorophylls. The carotenoid-to-polyunsaturated fatty acid molar ratio was taken as a comparison parameter in samples ofUlva rigida collected in differentloci and seasons; the value was markedly higher in samples from the Lagoon of Venice than from marine coastal waters. The total cholesterol concentration was evaluated by¹H-NMR spectroscopy and similar values were found for all species. Two-dimensional heterocorrelated NMR spectroscopy was shown to give characteristic fingerprints of the lipid extracts from algal samples as regards the content in chlorophylls, unsaturated fatty acids and carotenoids.author for correspondence     

Use of resazurin to detect mefloquine as an efflux-pump inhibitor in Pseudomonas aeruginosa and Escherichia coli

Multi-drug-resistant bacteria can cause serious infections that are extremely difficult to treat. Bacterial efflux pumps are known to contribute to multi-drug resistance and, thus, constitute a promising target for novel antibacterial agents. Resazurin is widely used to monitor bacterial growth because resazurin is reduced to the fluorescent resorufin by live cells. We have shown by flow cytometric analysis and by accumulation studies with wild type and efflux deficient strains that resazurin is a substrate of efflux pumps in Escherichia coli and Pseudomonas aeruginosa. Our investigations showed that the conversion rate of resazurin to resorufin is affected by efflux pumps. This finding was used to design an assay useful to detect efflux pump activity and to find potential efflux-pump inhibitors in a microtiter plate format. Mefloquine was detected as efflux-pump inhibitor when a panel of selected chemical compounds was tested for assay validation purposes.     

The use and misuse of calcium carbonate as an aid to the spectrophotometric assay of phytochrome in vitro

Supernatant and resuspended pellet samples from a centrifugation of homogenised, etiolated oat seedlings were prepared and assayed spectrophotometrically for phytochrome in the presence and absence of added calcium carbonate (CaCO₃) particles under a variety of conditions. At a constant sample thickness, in the absence of CaCO₃, increasing sample concentration had no significant effect on the expected phytochrome reading. In the presence of CaCO₃, however, as sample concentration increased, the phytochrome reading was less than, expected more so in resuspended pellet samples than in supernatant samples. At a constant sample concentration in the absence of CaCO₃, increasing sample thickness gave no significant difference from the excepted phytochrome reading in supernatant samples, but led to a slight increase over the expected phytochrome reading in resuspended pellet samples. In the presence of CaCO₃, increasing sample thickness led to a drop from the expected phytochrome reading in both sample types, but more so in resuspended pellet samples. These findings show that the use of CaCO₃ as an aid to spectrophotometric phytochrome assay can lead to large artifacts in the instrument reading and that its use should be approached with caution.     

Ectomycorrhizal syntheses with Picea abies and three fungal species: a case study on the use of an in vitro technique to identify naturally occurring ectomycorrhizae

Ectomycorrhizal syntheses between Picea abies and the fungal associates Scleroderma citrinum, Boletus luridus, and Tricholoma vaccinum were carried out using Melin's Erlenmeyer flask technique. The symbioses of S. citrinum were characterized by a mantle composed of an outer prosenchymatous and an inner synenchymatous layer. The mantles of B. luridus and T. vaccinum were solely prosenchymatous. Rhizomorphs were produced in all treatments, but only in association with S. citrinum were they differentiated with additional, enlarged hyphae. All synthesized ectomycorrhizae were white or whitish to light orange and greyishorange. On large-scale root sampling in two differing Picea abies forests in Switzerland, nine out of a total of 22 morphological types of ectomycorrhizae were white or yellow in colour and were, therefore, comparable with the synthesized ectomycorrhizae. These nine natural types generally had distinct mantle features (irregular synenchyma, gelatinous matrix, cystides, thick-walled hyphae), but mostly lacked clamp connections. Synthesized ectomycorrhizae, on the other hand, lacked distinct mantle characteristics and always had clamp connections. Natural and synthesized white or yellow ectomycorrhizae did not coincide morphologically and thus identification of the fungal partners of natural symbioses by means of in vitro-synthesis with potential ectomycorrhizal fungi was not possible in the present study.     

Mono- and polyclonal antibodies as probes to study vitellin processing in embryos of the stick insect Carausius morosus

During embryonic development, insect vitellins (Vt) are degraded by limited proteolysis to yield a number of lower-molecular weight polypeptides. The aim of the present study was to identify these polypeptides in the embryo and to verify how they relate to Vt polypeptides deposited in the oocyte during vitellogenesis. To this end a panel of poly- and monoclonal antibodies (Pab, Mab) was raised against Vt polypeptides and employed by immunoelectrophoresis and immunoblotting on embryos belonging to different developmental stages. Through this approach three major staining patterns were observed. First, Mab 4 reacts with both polypeptides B₁ and E₂₀, suggesting that polypeptide B₁ is gradually trimmed to yield polypeptide E₂₀ in late embryos. Second, Mab 12 is specific for polypeptide A₃ which is retained unchanged throughout embryogenesis. Third, Pab anti-A₂ and Mab 13 show that polypeptide A₂ is processed to yield polypeptide E₉ through limited proteolysis. In conclusion, the staining patterns reported in this study show that Vt polypeptides in developing embryos of the stick insect Carausius morosus undergo at least two major processing events concerning polypeptides B₁ and A₂.     

A pilot study on lignocelluloses to ethanol and fish feed using NMMO pretreatment and cultivation with zygomycetes in an air-lift reactor

A complete process for the production of bioethanol and fungal biomass from spruce and birch was investigated. The process included milling, pretreatment with N-methylmorpholine-N-oxide (NMMO), washing of the pretreated wood, enzymatic hydrolysis, and cultivation of the zygomycetes fungi Mucor indicus. Investigated factors included wood chip size (0.5-16 mm), pretreatment time (1-5 h), and scale of the process from bench-scale to 2 m high air-lift reactor. Best hydrolysis yields were achieved from wood chips below 2 mm after 5 h of pretreatment. Ethanol yields (mg/g wood) of 195 and 128 for spruce, and 175 and 136 for birch were achieved from bench-scale and airlift, respectively. Fungal biomass yields (mg/g wood) of 103 and 70 for spruce, and 86 and 66 for birch from bench scale and airlift respectively were simultaneously achieved. NMMO pretreatment and cultivation with M. indicus appear to be a good alternative for ethanol production from birch and spruce.     

Variation with soil depth,topographic position and host species in the capacity of soils from an Australian locale to nodulateCasuarina andAllocasuarina seedlings

Sandy alluvial soils in a floodplain supporting a native stand ofCasuarina cunninghamiana Miq. produced about three times as many nodulated seedlings and more than twice as many nodules per nodulated seedling on roots of baitedCasuarina spp. than did clay loam red earth soils from the adjacent valley slope. Moist and well-aerated subsurficial alluvial sands had the greatest nodulation capacity of all the soils sampled. For all topographic positions, soil samples from depths greater than 20 cm promoted 76% more nodulated Casuarina seedlings than samples from the surficial 20 cm.Seedlings of three provenances ofC. cunninghamiana, together with seedlings ofC. glauca Sieb. ex Spreng.,C. cristata F. Muell ex Miq. andC. obesa Miq. developed significantly more nodules per pot and nodules per nodulated seedling in soils from this locale than seedlings of twoCasuarina equisetifolia Forst. provenances. Seedlings of two provenances ofAllocasuarina torulosa (Ait.) L. Johnson had fewer than 1% nodulated seedlings, a significantly lower level by far than that ofCasuarina seedlings.A. torulosa provenances also had significantly fewer nodulated seedlings per pot and nodules per nodulated seedling than all Casuarina hosts excepting one poorly-nodulated provenance ofC. equisetifolia.Nodulated seedlings of allCasuarina species had the capacity to fix atmospheric N₂, as indicated by acetylene-reduction capability. The presence of yellow cladodes and low rates of acetylene reduction per plant forC. cristata Miq. suggest that this association was poorly effective.