Foraging behavior of a generalist marine top predator,Japanese cormorants (<Emphasis Type="Italic">Phalacrocorax filamentosus</Emphasis>), in years of demersal versus epipelagic prey

To examine the behavioral adjustment of a generalist marine top predator to variability of their prey, we studied the foraging behavior of Japanese cormorants (Phalacrocorax filamentosus) breeding at Teuri Island, Hokkaido, in years of contrasting demersal and epipelagic prey composition. We used radio telemetry and ship-based surveys to determine behavior and at-sea distribution during three summers (1996–1998). The cormorants fed on epipelagic anchovy (Engraulis japonicus) and sandlance (Ammodytes personatus) in 1998 (year of epipelagic diet), while they fed on benthic rock fish (Sebastes spp.) and flatfish (Pleuronectidae) and nearshore-living naked sandlance (Hypophychus dybowskii), as well as epibenthic greenling (Hexagrammidae) in 1996 and 1997 (year of demersal diet). Cormorants engaged in larger feeding groups, visited more feeding sites, and stayed at each feeding site for a shorter period in the year of epipelagic diet than in the years of demersal diet. The cormorants made long foraging trips and fed in the mainland coastal habitat, distant from the colony, in the years of demersal diet. Individual radio-tracked birds fed over the wide area between the islands and mainland, in the year of epipelagic diet, while most individuals specialized in mainland or island coastal habitats in the years of demersal diet. Behavioral adjustment of Japanese cormorants might allow them to exploit both unpredictable epipelagic and predictable benthic prey efficiently.Communicated by T. Ikeda, Hakodate     

New biofidelic corridor and biofidelity test procedure for pedestrian legform impactors

The objectives of this research are to propose a new impact response corridor for the ISO legform impactor and to determine the biofidelity of the current legform impactor with rigid leg and thigh developed by the Transport Research Laboratory (TRL). The latest data obtained from Post Mortem Human Subject (PMHS) knee impact tests were analyzed in connection with the proposal, and biofidelity legform impact tests were conducted using the current rigid legform impactor. New normalized biofidelic corridors of impact force corresponding to adult male 50th percentile (AM50) are proposed. The impact test results indicate the current rigid legform impactor does not have sufficient human knee biofidelity. The present results suggest that human tolerance can not be used directly for the injury reference value of the legform impactor. A conversion method is needed to interpret the data measured by current legform impactors as the injury reference value.     

Pulverization of waste printed circuit boards

A new pulverization method to reduce the volume of waste printed circuit boards is reported. About 50% of printed circuit boards with integrate circuits (ICs) could be pulverized by our method in one 20-min batch, but boards without ICs could not be pulverized. By repeating the process three times, about 95% of printed circuit boards with ICs could be made into a fine powder with particles less than 106µm. A weight-drop test was also performed to examine the strength of the printed circuit boards and clarify the mechanism of pulverization. When a weight was dropped on the solder-welding side of the board ruptures occurred more easily than when the weight was dropped on the IC-mounted side. With a heavy weight, the IC was fractured more easily when the potential energy was low. Where the stress was concentrated, two types of rupture location were found on printed circuit boards with ICs. One was where the IC was connected to the printed circuit board. The other was where the surface had undulations. It also became clear that the fracture of printed circuit boards depends on the impacting weight rather than on the potential energy.     

A numerical modeling approach to support decision-making on design of integrated multitrophic aquaculture for efficiently mitigating aquatic waste

As a bio-mitigation strategy of aquafarming pollutants, the integrated multitrophic aquaculture (IMTA) system has been proposed and developed to mitigate the waste produced during co-cultivation. Although there have been considerable implementations of IMTA worldwide, its optimal design needs a further study. Through a numerical modeling approach, this study aims to facilitate decision-making when designing IMTA to more efficiently mitigate the negative change caused by aquaculture. An improved three-dimensional numerical model is adopted to simulate the dynamics of water current and organic waste in Gokasho Bay, Japan. Results show that (1) the maximum main surface water current velocity in Hazama-ura area is less than 10 cm s^?1, where nutrient absorbers and/or suspended feeders can easily attach to a substratum; (2) southern-eastern direction water flow is dominant through the year suggesting that seaweeds (e.g., Laminaria japonica, Ulva ohnoi) or mussels (e.g., Mytilus edulis) are better arranged in the same direction; (3) horizontal distribution of organic waste on sea bottom indicates that when releasing sea cucumbers (e.g., Apostichopus japonicus), priority is given to the areas where the accumulated amount of particulate organic waste is high. Our case study provides a general idea on the optimal design of IMTA and can be scaled to the globe, especially regarding decision-making on locations for the extractive organisms. In conclusion, to improve the bio-mitigation efficiency of IMTA, location for nutrient absorbers and/or suspended feeders can be selected based on local water flow, and sea cucumbers need to be placed with a careful consideration of the waste distribution in local area.     

Ultrasonic courtship song in the Asian corn borer moth, Ostrinia furnacalis

Although sex pheromone communication in the genus Ostrinia (Lepidoptera: Crambidae) has been studied intensively, acoustic communication in this genus has not been explored. In this study, we report that male-produced ultrasound serves as a courtship song in the Asian corn borer moth, O. furnacalis. Upon landing close to a pheromone-releasing female, a male showed a series of courtship behaviors involving emission of ultrasound. The sounds were produced when the wings were vibrated quickly in an upright position. The male song was composed of chirps, i.e., groups of pulses (duration of a chirp = 58.9 ms, 8.8 pulses/chirp), with a broadband frequency of 25–100 kHz. In flight tunnel experiments, deaf and hearing females showed a significant difference in the incidence of three behavioral responses to courting males, i.e., immediate acceptance, acceptance after walking, and rejection. Deaf females showed more ‘rejection’ and less ‘acceptance after walking’ than hearing females, indicating that the detection of male-produced ultrasound plays an important role in the acceptance of a male. The findings are discussed in the context of exploitation of receiver bias and mate choice.     

Development of injury criteria for pelvic fracture in frontal crashes

OBJECTIVE: This article assesses the position-dependent injury tolerance of the hip in the frontal direction based on testing of eight postmortem human subjects. METHODS: For each subject, the left and right hemipelvis complex was axially loaded using a previously developed test configuration. Six positions were defined from a seated femur neutral condition, combining flexed, neutral, and extended femur positions with abducted, neutral, and adducted positions. RESULTS: Axial injury tolerances based on peak force were found to be 6,850 +/- 840 N in the extended, neutral position and 4,080 +/- 830 N in the flexed, neutral position. From the flexed neutral orientation, the peak axial force increased 18% for 20 degrees abduction and decreased 6% for 20 degrees adduction. From the extended, neutral orientation, the peak axial force decreased 4% for 20 degrees abduction and decreased 3% for 20 degrees adduction. However, as there is evidence that increases in loading may occur after the initiation of fracture, the magnitude of the peak force is likely related to the extent of injury, not to the initial tolerance. Using the axial femur force at the initiation of fracture (assessed with acoustic crack sensors) as a potentially more relevant indicator of injury may lower the existing injury criteria. This fracture initiation force varied by position from 3,010 +/- 560 N in the flexed, neutral position to 5,470 N in the extended, abducted position. Further, there was a large position-dependent variation in the ratio of fracture initiation force to the peak axial force. The initiation of fracture was 83% of the peak axial force in the extended, abducted position, but the ratio was 34% in the extended, adducted position. CONCLUSIONS: This may have significant implications for the development of pelvic injury criteria by automobile designers attempting to mitigate pelvis injuries.     

Contamination status of persistent organochlorines in human breast milk from Japan: recent levels and temporal trend

Contamination levels of persistent organochlorines (OCs) such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), and chlordane compounds (CHLs) was examined in human breast milk collected during 2001-2004 from Fukuoka prefecture in Japan. The concentrations of OCs such as dioxins and related compounds, DDTs, CHLs and HCB in human breast milk from primiparae were comparable to or slightly higher than the data obtained during 1998, indicating that the levels of these contaminants in Japanese human breast milk have not decreased since 1998 and Japanese are continuously exposed to these chemicals, presumably via fish intake. In addition, OC levels in human breast milk from primiparae were significantly higher than those from multiparae, implying elimination of OCs via lactation. Furthermore, significant positive correlations were observed between levels of OCs in human breast milk and the age of primiparae. These results indicate that the mothers with higher age may transfer higher amounts of OCs to the first infant than to the infants born afterwards through breast-feeding, and hence the first born children might be at higher risk by OCs.     

Hydrodynamic forces on emergent cylinders in non-uniform flow

Environmental Fluid Mechanics - The main objective of conducting numerical simulations of flows in rivers with vegetation is to investigate the complex flow dynamics involved in non-equilibrium...     

Methods for selenium removal from contaminated waters: a review

Environmental Chemistry Letters - Worldwide contamination of waters by metals, metalloids, and organometallic pollutants is a major health issue. In particular, the occurrence of the selenium...