Temporal and interspecific dietary variation in wintering ducks in agricultural landscapes.

Farmlands are becoming more important as waterfowl foraging habitats, while natural wetlands are being lost globally. However, it is unclear how waterfowl coexist in agricultural landscapes by resource partitioning. We evaluated the diets of seven sympatric dabbling ducks foraging in rice paddy and lotus fields around Lake Kasumigaura, the second largest lake in Japan, during two wintering seasons (from November to February) by faecal DNA metabarcoding using chloroplast trnL and mitochondrial CO1 region sequences. We examined 420 faecal samples and found different patterns of dietary diversity and composition among the duck species. The pattern also differed between plant and invertebrate food. Dietary niche partitioning was clear in plant food. Large-bodied ducks intensively use crop plants, and other ducks might mediate competition by using terrestrial and aquatic plants that are suitable for their foraging behaviours or microhabitats. Dietary segregation among species was the most apparent in February, when the abundance of foraging ducks was the largest. This study illustrated the complex pattern of dietary niche partitioning of dabbling ducks in agricultural landscapes, which might be difficult to evaluate by conventional approaches. The availability of crop plants, as well as other plant food resources in flooted areas and farmland dikes, may enable ducks to coexist by spatial or behavioural resource partitioning.

Design and determination of new bimodal pore catalyst structure with hetero atom combination by inside-pore organization of nano-particles from sol.

A catalyst support with spatially-connected small pores and large pores, as a distinct bimodal pore structure, has been developed, which has excellent advantages in solid-catalysis reactions because the large pores provide pathways for rapid molecular transportation and the small pores serve a large area of active surface. The obtained ZrO2-SiO2 bimodal support loaded with cobalt was applied in slurry-phase Fischer-Tropsch synthesis (FTS). The bimodal catalyst presented the best reaction performance in slurry-phase FTS as higher reaction rate and lower methane selectivity, because the spatially promotional effect of bimodal structure and the chemically promotional effect of the porous zirconia were available at the same time inside the large pores of original silica gel.

The potential of the scanning low energy electron microscopy for the examination of aluminum based alloys and composites.

When studying the physical properties and technological parameters of aluminum-based alloys and composites, some partial tasks, connected with the microstructure of the material bulk, pose a problem for established microscopic techniques. The topography and distribution of sub-micrometer sized precipitates and of segregations on the particle/matrix interface, for example, are difficult to observe by conventional methods of transmission and scanning electron microscopy. The introduction of a high-resolution low-energy mode into the scanning electron microscope, relying on the deceleration of an already formed and focused primary beam just in front of the specimen, enables one to browse over the full electron energy range with great ease. This method offers added value consisting of the diminished interaction volume of electrons, the favorable combination of secondary and backscattered electron signals emitted at increased yields and collected at extremely high efficiency and the availability of unconventional contrasts excited by slow electrons. Demonstration experiments have been performed on structures based on the Al-Mg-Si alloy, and oriented towards examination of the Mg-Si precipitates in the alloy and sub-micrometer spinel crystals growing on the matrix-ceramic interface in a composite filled with alumina particles.

Lead tolerance and accumulation in the gametophytes of the fern Athyrium yokoscense.

The fern Athyrium yokoscense is known to be highly tolerant to lead toxicity, and is a lead hyperaccumulator that can accumulate over 1,000 microg g(-1) of lead in its dry matter. In this work, we examined whether the gametophytic generation of A. yokoscense also resists lead toxicity like the sporophytic generation. Spore germination in A. yokoscense was more tolerant to Pb2+, compared to that in other fern species, such as Pteridium aquilinum, Lygodium japonicum and Pteris vittata. In addition, the early gametophyte development of A. yokoscense was not much affected by 10 microM Pb2+, as evaluated from the prothallial growth and rhizoid development. We also showed that Athyrium gametophytes could accumulate more than 10,000 microg g(-1) of lead, and that the lead was localized in the cytosol and vacuole of rhizoidal cells, as determined by a transmission electron micrograph. These results indicate that Athyrium gametophytes have the ability to accumulate lead in the rhizoids. Furthermore, the gametophytes were found to include a large amount of proanthocyanidins (condensed tannins). Because proanthocyanidins have a latent ability to complex with lead ions, the possible roles of proanthocyanidins in the lead tolerance and accumulation of Athyrium gametophytes are discussed.