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Featured Application: Our findings provide a crucial perspective on a novel accumulation effect of diatom resting stages by the deployment of artificial reefs, which may enhance the primary production of the overlying water column, subsequently contributing to the augmentation of fishery productivity through food chains. Artificial reefs (ARs) have multiple beneficial effects involved in increased fishery production. The present study investigated diatom resting stages in the sediments near ARs at a depth of about 90 m by the combined use of direct microscopic observation and the MPN method, seeking a novel function of AR deployment that potentially increases biological production. Although the concentration of diatom resting stages at A2 (north end station of the AR area), composed mainly of Chaetoceros, was ten times the concentration at A5 (non-reef station), the concentration at A1 (south end station of the AR area) was the same level as at A5. These results suggest that the AR contributes to the accumulation of diatom resting stages while the degree of accumulation is attributed to the arrangement of ARs and their physical environment such as flow directions. Interestingly, live pennate diatoms possessing photosynthetic pigments were constantly observed in all samples despite the low light intensity (≤1.2 µmol photons m−2 s−1), which provides new ecological insight into their biological and physiological characteristics. In this study, the distribution of viable diatom resting stages and live pennate diatoms in the sediment around ARs in a dysphotic zone was revealed for the first time, casting a light on the novel function of ARs potentially enhancing primary production around them. [ABSTRACT FROM AUTHOR]

We devised a simple and rapid technique for establishing axenic cultures of centric diatoms by sieving and washing resting stage cells. This technique is an effective means for establishing the axenic cultures of species that have endogenous resting spores. The primary advantage of this method is in the isolation of cells when the target species is absent from the water column. [ABSTRACT FROM AUTHOR]

We determined the complete sequences of the plastid and mitochondrial genomes of three non-photosynthetic Nitzschia spp., as well as those of a photosynthetic close relative, Nitzschia palea . All the plastid genomes and the three mitochondrial genomes determined were found to be circularly mapping, and the other mitochondrial genomes were predicted to be of a linear form with telomere-like structures at both ends. We found that all the non-photosynthetic plastid genomes are streamlined and lack a common gene set: two RNA genes, and 60 protein-coding genes, most of which are related to photosynthetic functions. Nevertheless, the non-photosynthetic plastid genomes commonly retain ATP synthase complex genes, although atpE is missing in Nitzschia sp. NIES-3581 and three other non-photosynthetic species lack atpF instead of atpE. This observation suggests an evolutionary constraint against the loss of ATP synthase complex genes. All the non-photosynthetic diatom plastid genomes lacked two genes, thiS and thiG, involved in thiamin biosynthesis. Consistent with this gene loss, non-photosynthetic Nitzschia spp. were incapable of thriving in vitamin B1-lacking media. This study clearly demonstrated not only the evolutionary trends of plastid genome reduction but also the linkage between plastid genome reduction and a biological change of nutrient requirements in Nitzschia . [ABSTRACT FROM AUTHOR]

Information on diatom resting stages is fundamentally important to understanding the population dynamics of diatoms including bloom formation. The distribution of viable diatom resting stage cells in bottom sediments of the eastern Bering Sea in July 2009 was investigated by the most probable number (MPN) method. The abundances of diatom resting stage cells ranged from 1.7×103 to 1.2×106 MPNcellscm−3 wet sediment, comparable to those in shallow eutrophic areas where diatom blooms frequently occur. Common species during the spring phytoplankton bloom in the eastern Bering Sea were also dominant in sediments as resting stage cells. It should be noted that relatively high numbers of ice algae species, especially ribbon-shaped chain forming pennate diatoms, were found in the sediments. The life cycle strategy using resting stage cells allows planktonic and ice algal species to survive unfavorable environmental conditions such as the dark winter season, and potentially contribute to form blooms of several types (subsurface of ice, ice edge, plankton) through vertical mixing. [ABSTRACT FROM AUTHOR]

I shii K.-I., I wataki M., M atsuoka K. and I mai I. 2011. Proposal of identification criteria for resting spores of species (Bacillariophyceae) from a temperate coastal sea. 50: 351--362. DOI: 10.2216/10-36.1 is a large, ecologically important genus of marine planktonic diatoms. Many species of form resting spores to survive environmental stress. Species identification based on morphological characteristics of resting spores is difficult. In the present study, we proposed a flow diagram for the identification of species based on morphology. Resting spores of 18 species were identified in water and sediment samples from southern Japan and the East China Sea based on morphological characteristics of resting spores and/or the vegetative cells containing them. A single ring of puncta was found to be the most important morphological feature of resting spores for species identification, by which the positions of primary and secondary valves were correctly determined. Other morphological characteristics such as features of the primary valve face, margins of the primary and secondary valve mantles, and secondary valve face are also useful for species identification. A combination of these morphological characteristics was used to construct a flow diagram for identification of the 18 species found in our samples with light microscopy. This flow diagram is most applicable to Japanese waters, but the approach should be refined and improved to understand the biology and ecology of species in any marine ecosystem. [ABSTRACT FROM AUTHOR]

Conventional methods of gender recognition cannot be applied to counting store customers in terms of both data acquisition conditions and processing time. To solve this problem, the authors proposed a gender recognition method based on human silhouette shape characteristics. The current study demonstrated for the first time how efficient the footstep characteristic and foot pressure characteristic are for gender recognition. It discussed the recognition technique based on joining of the mentioned characteristics with the silhouette characteristic. These were joined by the one-dimensional compression based on the Fischer discrimination of characteristic vectors arranged in the order of characteristic rates for these three types. Based on the results of clothing-related research aimed at department store customers, a population group consisting of 45 male and 45 female participants was gathered to simulate distribution of various types of clothing and footwear. The authors conducted recognition tests with this population group and examined distributions by types of clothes and footwear in the characteristic space. The results showed that (1) for each separate characteristic rate the recognition rate which used to be 80% increased up to 90% due to use of joint characteristics, (2) there were numerous samples that featured correct recognition by the footstep characteristic or foot pressure characteristic even with erroneous recognition by the silhouette characteristic, which demonstrated effectiveness of the proposed combination of the three types of characteristic rates. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(8): 54–64, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10066 [ABSTRACT FROM AUTHOR]

1 The involvement of bradykinin (BK) B[sub 2] receptor in acute pancreatitis induced by pancreaticobiliary duct ligation was investigated in rats. 2 The activities of amylase and lipase in the serum, the water content of the pancreas, and vacuolization of the acinar cells were significantly increased 2 h after obstruction of the duct in Sprague-Dawley rats. 3 Elevated serum amylase activity, increased pancreatic oedema, and damage of the pancreatic tissue were significantly less marked in plasma kininogen-deficient, B/N-Katholiek rats than in the normal strain, B/N-Kitasato rats 2 h after the ligation. 4 Obstruction of the pancreaticobiliary duct augmented the level of (1-5)-BK (Arg¹-Pro²-Pro³-Gly[sup 4]Phe[sup 5]), a stable BK metabolite, in the blood from 73.0±21.7 pg ml[sup -1] at 0 h to 149.8 ± 38.0 pg ml[sup -1] at 2 h after the induction of pancreatitis in SD rats. 5 Administration of a BK B[sub 2] receptor antagonist, FR173657 (100 mg kg[sup -1], p.o.) or Hoel40 (100 nmol kg[sup -1,, s.c.), reduced the elevation of amylase and lipase activities in the serum and of pancreatic water content in a dose-dependent manner. The effective attenuation of oedema formation and vacuolization by the antagonists was also confirmed light-microscopically. In contrast, treatment with gabexate mesilate or indomethacin did not cause significant suppression of the pancreatitis. 6 These findings suggest a possible involvement of kinin B[sub 2] receptor in the present pancreatitis model. Furthermore, they point to the potential usefulness of the B[sub 2] receptor in clinical acute pancreatitis. [ABSTRACT FROM AUTHOR]

This paper proposes an automatic method of extracting the image of a vehicle moving along a straight road from a sequential video image. The method has been designed to be independent of the type of vehicle and the background, and to obtain an image with minimum defective areas. The image of the vehicle is extracted by analyzing a locus in a spatio-temporal image seen through a slit in a fixed video camera, by updating the background image and superimposing a time-series of the background difference image. The method can extract a full image of various types of vehicles in an arbitrary background with minimum defects, and can separate the images of two vehicles when one crosses in front of the other. The method has been tested successfully with actual traffic (including traffic starting from a traffic light). The results show that the method is practical fox smoothly Bowing traffic. The method has also been tested successfully for identifying vehicle types. [ABSTRACT FROM AUTHOR]

The algicidal and growth-inhibiting bacteria associated with seagrasses and macroalgae were characterized during the summer of 2012 and 2013 throughout Puget Sound, WA, USA. In 2012, Heterosigma akashiwo -killing bacteria were observed in concentrations of 2.8 × 10 6 CFU g −1 wet in the outer organic layer (biofilm) on the common eelgrass ( Zostera marina ) in north Padilla Bay. Bacteria that inhibited the growth of Alexandrium tamarense were detected within the biofilm formed on the eelgrass canopy at Dumas Bay and North Bay at densities of ∼10 8 CFU g −1 wet weight. Additionally, up to 4100 CFU mL −1 of algicidal and growth-inhibiting bacteria affecting both A. tamarense and H. akashiwo were detected in seawater adjacent to seven different eelgrass beds. In 2013, H. akashiwo -killing bacteria were found on Z. marina and Ulva lactuca with the highest densities of ∼10 8 CFU g −1 wet weight at Shallow Bay, Sucia Island. Bacteria that inhibited the growth of H. akashiwo and A. tamarense were also detected on Z. marina and Z. japonica at central Padilla Bay. Heterosigma akashiwo cysts were detected at a concentration of 3400 cysts g −1 wet weight in the sediment from Westcott Bay (northern San Juan Island), a location where eelgrass disappeared in 2002. These findings provide new insights on the ecology of algicidal and growth-inhibiting bacteria, and suggest that seagrass and macroalgae provide an environment that may influence the abundance of harmful algae in this region. This work highlights the importance of protection and restoration of native seagrasses and macroalgae in nearshore environments, in particular those regions where shellfish restoration initiatives are in place to satisfy a growing demand for seafood. [ABSTRACT FROM AUTHOR]

Secondary loss of photosynthesis is observed across almost all plastid-bearing branches of the eukaryotic tree of life. However, genome-based insights into the transition from a phototroph into a secondary heterotroph have so far only been revealed for parasitic species. Free-living organisms can yield unique insights into the evolutionary consequence of the loss of photosynthesis, as the parasitic lifestyle requires specific adaptations to host environments. Here, we report on the diploid genome of the free-living diatom Nitzschia putrida (35 Mbp), a nonphotosynthetic osmotroph whose photosynthetic relatives contribute ca. 40% of net oceanic primary production. Comparative analyses with photosynthetic diatoms and heterotrophic algae with parasitic lifestyle revealed that a combination of gene loss, the accumulation of genes involved in organic carbon degradation, a unique secretome, and the rapid divergence of conserved gene families involved in cell wall and extracellular metabolism appear to have facilitated the lifestyle of a free-living secondary heterotroph.

Tumor necrosis factor-alpha (TNFalpha) and interleukin-1 (IL-1) have been recognized as key proinflammatory mediators in the pathogenesis of lipopolysaccharide (LPS)-induced liver injury. In the present study we examined the effect of FR167653, a novel inhibitor of TNFalpha and IL-1 synthesis, on the hepatic microvascular response to LPS using in vivo microscopy. Significant hepatic microvascular responses comprising leukocyte adhesion to the sinusoidal wall and central venules and reduced sinusoidal perfusion appeared 2 and 4 h after LPS (0.1 mg/kg, i.v.) injection in male C3H/HeN mice (LPS sensitive) when compared with male C3H/HeJ mice (LPS resistant). The serum concentrations of TNFalpha at 1.5 h and IL-1beta at 4 h after injection of LPS, as determined by enzyme-linked immunosorbent assay, were significantly higher in C3H/HeN mice than in C3H/HeJ mice. Administration of murine TNFalpha or IL-1beta (10 microg/kg., i.v., respectively) in both C3H/HeN and C3H/HeJ mice elicited the hepatic microvascular responses that were similar to those produced by LPS injection in C3H/HeN mice. FR167653 (1 and 10 mg/kg, i.v., 0 and 2 h after LPS injection) significantly reduced leukocyte adhesion and restored sinusoidal perfusion in a dose-dependent manner in C3H/HeN mice 4 h after LPS injection. The levels of TNFalpha, IL-1beta, and alanine aminotransferase also were significantly lower in FR167653-treated endotoxemic C3H/HeN mice than those in vehicle-treated endotoxemic animals. The results suggest that the hepatic microvascular response to LPS is partly mediated by TNFalpha and IL-1beta, and that FR167653 prevents LPS-induced hepatic microcirculatory dysfunction by inhibiting the production of TNFalpha and IL-1beta.