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1.
Oguchi M Murakami S Sakanakura H Kida A Kameya T 《Waste management (New York, N.Y.)》2011,31(9-10):2150-2160
End-of-life electrical and electronic equipment (EEE) has recently received attention as a secondary source of metals. This study examined characteristics of end-of-life EEE as secondary metal resources to consider efficient collection and metal recovery systems according to the specific metals and types of EEE. We constructed an analogy between natural resource development and metal recovery from end-of-life EEE and found that metal content and total annual amount of metal contained in each type of end-of-life EEE should be considered in secondary resource development, as well as the collectability of the end-of-life products. We then categorized 21 EEE types into five groups and discussed their potential as secondary metal resources. Refrigerators, washing machines, air conditioners, and CRT TVs were evaluated as the most important sources of common metals, and personal computers, mobile phones, and video games were evaluated as the most important sources of precious metals. Several types of small digital equipment were also identified as important sources of precious metals; however, mid-size information and communication technology (ICT) equipment (e.g., printers and fax machines) and audio/video equipment were shown to be more important as a source of a variety of less common metals. The physical collectability of each type of EEE was roughly characterized by unit size and number of end-of-life products generated annually. Current collection systems in Japan were examined and potentially appropriate collection methods were suggested for equipment types that currently have no specific collection systems in Japan, particularly for video games, notebook computers, and mid-size ICT and audio/video equipment. 相似文献
2.
Hiromi Iwasaki Akiko Kyuno Mifue Shintaku Yuko Fujita Yoshihiro Fujiwara Katsunori Fujikura Jun Hashimoto Leonardo de Oliveira Martins Andrey Gebruk Jun-Ichi Miyazaki 《Marine Biology》2006,149(5):1111-1122
In order to elucidate the evolutionary process of deep-sea Bathymodiolus mussels, we investigated the phylogenetic relationships of 16 species worldwide by analyzing nucleotide sequences of the mitochondrial COI and ND4 genes. Deep-sea mussels were clustered into three groups by basal trichotomous divergence. The first was composed of four species found in Japanese waters and one species from the Gulf of Mexico, which contain methanotrophic endosymbiotic bacteria. The second included nine species distributed in the West and East Pacific, Indian, and Atlantic Oceans. Members of the second group were trichotomously divided into the Indo-West Pacific, Atlantic, and East Pacific subclusters. The Indo-West Pacific subcluster was composed of three very closely related species with mutual genetic distances at the intraspecific level (av. 0.019 in COI and 0.009 in ND4 relative to av. 0.156 in COI and 0.265 in ND4 among Bathymodiolus species other than Cluster A species), suggesting some gene flow among these species. The third consisted of two West Pacific species. Species in the second and third groups contain mainly thioautotrophic endosymbionts, including some species harboring both methanotrophs and thioautotrophs. 相似文献
3.
Akiko Matsumoto-Oda Miya Hamai Hitosige Hayaki Kazuhiko Hosaka Kevin D. Hunt Eiiti Kasuya Kenji Kawanaka John C. Mitani Hiroyuki Takasaki Yukio Takahata 《Behavioral ecology and sociobiology》2007,61(5):661-668
Although estrous synchrony has been reported in a number of mammalian species, most often among primates, methodological and
analytical problems make it difficult to interpret these results. We developed a novel estrous synchrony index and employed
a randomization procedure to analyze long-term observations of female chimpanzee (Pan troglodytes schweinfurthii) estrous cycles at the Mahale Mountains National Park, Tanzania. Our results revealed that female chimpanzees at Mahale avoid
synchronizing their estrous periods with each other. We also found that birthrates decreased as the breeding sex ratio increased.
We suggest that estrous asynchrony decreases female–female competition for mates. Asynchrony may also reduce the potential
for male sexual coercion by nonpreferred mating partners. 相似文献
4.
André Chiaradia Yan Ropert-Coudert Akiko Kato Thomas Mattern Julija Yorke 《Marine Biology》2007,151(4):1535-1542
Little Penguins, Eudyptula minor, breed in several small colonies in New Zealand and Australia. In this study, we compare the birds’ diving performances at
different sites situated throughout their breeding range. Environmental conditions and breeding success vary drastically amongst
colonies, but all birds feed on similar types of prey and face similar limitations on their foraging range. We examined several
diving parameters and calculated the proportion of foraging zone available during breeding to examine whether oceanographic
and geographic factors in the foraging zone can explain variations in diving behaviour and fledging success among the different
colonies. In colonies with high fledging success, Penguin Island and Oamaru, penguins made shallow dives <50 m depth and had
lower diving effort. More than 90% of the foraging zone was in waters <50 m depth in these colonies. Motuara Island also has
shallow waters with 95% <50 m depth, but the fledging success was low. Phillip Island has only 42% of waters <50 m and comparatively
low fledging success. Thus, penguins dived deeper and showed a higher diving effort in colonies with lower fledging success
(Motuara Island and Phillip Island), indicating that they were disadvantaged compared to conspecifics from other colonies
that dived shallower and with a lesser diving effort. We concluded that bathymetry is an important factor, but not the only
one, which influences fledging success. 相似文献
5.
Information about foraging speeds is particularly valuable when the impact of a predator species upon a community of prey has to be defined, as in the case of great cormorants. We measured the swim speed of 12 (six males and six females) free-ranging great cormorants Phalacrocorax carbo, foraging off the Greenland coast during the summer of 2003, using miniaturized data-loggers. Although mean body mass of males was 27% greater than that of females, and mean swim speed of males were 29–57% higher than that of females during foraging phases (but not descent phases) of dives, these differences in speeds were not significant due to high variances. Birds descended to the mean maximum depth of 4.7 m at an average speed of 1.6±0.5 m s−1, a speed similar to that measured in captive cormorants in previous studies. Although bursts of up to 4 m s−1 were recorded, speed usually decreased during the deepest (foraging) phase of dives, being on average 0.8±0.6 m s−1. Speeds measured here should be taken with caution, because the large propeller loggers used to measure speed directly decreased descent speeds by up to 0.5 m s−1 when compared to smaller depth-only loggers. Cormorants in Greenland seem to combine two searching strategies, one requiring low speed to scan the water column or benthos, and one requiring high speed to pursue prey. These two strategies depend on the two main habitats of their prey: pelagic or demersal. 相似文献
6.
Akiko Matsumoto-Oda 《Behavioral ecology and sociobiology》1999,46(4):258-266
For female chimpanzees (Pan troglodytes schweinfurthii) in the Mahale Mountains National Park, Tanzania, the most common mating pattern is opportunistic. In such opportunistic
matings, females copulated promiscuously but not randomly. This study describes female mate choice during 1-year observation
of six females who exhibited regular genital-swelling cycles. During the study period, 169 opportunistic matings and four
restrictive matings were recorded over the course of 51 days. As female estrus progressed, mating frequency and the number
of adult male mating partners increased, although the number of potential mating partners did not change. Criteria of female
choice examined were the direction and consent/rejection of courtship, proximity maintenance, and female grooming. Adult-male
courtships were successful more often than those of adolescent males. During the earlier phase of estrus, females copulated
rather promiscuously with many males. But during the later phase of estrus when the likelihood of conception is expected to
be highest, they copulated repeatedly with high-ranking adult males. There was a positive correlation between female grooming
frequency and mating frequency when the likelihood of conception was greatest. Female chimpanzees are thought to choose high-ranking
males as fathers of their offspring. Moreover, female chimpanzees may adopt one or both of two mating strategies, i.e., a
many-male strategy and a best-male strategy.
Received: 23 November 1998 / Received in revised form: 12 April 1999 / Accepted: 26 April 1999 相似文献
7.
Maryline Le Vaillant Céline Le Bohec Onésime Prud’Homme Barbara Wienecke Yvon Le Maho Akiko Kato Yan Ropert-Coudert 《Marine Biology》2013,160(5):1147-1156
As predicted by life history theory, once recruited into the breeding population and with increasing age, long-lived animals should be able to manage more efficiently the conflict between self-maintenance and reproduction. Consequently, breeding performances should improve with age before stabilizing at a certain level. Using temperature–depth recorders and isotopic analysis, we tested how age affects the foraging behaviour of king penguin Aptenodytes patagonicus during one trip in the chick-rearing phase. Depending on sex and age, king penguins expressed two different foraging strategies. Older birds gained more daily mass per unit body mass than younger ones. Older females conducted shorter trips, dived deeper and performed more prey pursuits. They also had higher blood levels of δ15N than younger individuals and males indicating sex- and age-specific dietary regimes. However, we found no differences in carbon isotopic signature, suggesting that individuals exploited the same foraging areas independently of sex and age. Our results suggest that king penguins are able to increase the quantity of energy extracted with increasing age and that such a strategy is sex-related. Our study is the first to reveal of an interaction between age and sex in determining foraging efficiency in king penguins. 相似文献
8.
Nakazawa E Ikemoto T Hokura A Terada Y Kunito T Yamamoto T Yamada TK Rosas FC Fillmann G Tanabe S Nakai I 《Journal of environmental monitoring : JEM》2011,13(6):1678-1686
The chemical form of Ag in the livers of five species of marine mammals was examined using X-ray absorption fine structure (XAFS) and X-ray fluorescence (XRF) spectroscopies. The XAFS analysis suggested that Ag(2)Se was present in the livers of the Franciscana dolphin (Pontoporia blainvillei), Dall's porpoise (Phocoenoides dalli), and Baird's beaked whale (Berardius bairdii), whereas Ag(2)S was present in the livers of the striped dolphin (Stenella coeruleoalba) and pygmy killer whale (Feresa attenuata). XRF spectroscopy results revealed that the distribution patterns of Ag and Se in a thin section of the liver of the Franciscana dolphin were the same; this also implied that Ag was associated with Se in the liver. Thus, the interaction of Ag with Se or S may offer significant protection against the toxicity of Ag in marine mammals. The formation of either Ag(2)Se or Ag(2)S might depend on the Hg levels in the liver. Ag(2)Se was observed in liver samples with relatively high Ag/Hg ratio, whereas liver samples with low Ag/Hg ratio contained Ag(2)S. 相似文献
9.
Yukio Noma Sayuri Yamane Akiko Kida 《Journal of Material Cycles and Waste Management》2001,3(2):126-134
Adsorbable organic halides (AOX) and AOX formation potential (AOXFP) were investigated in 46 landfill lea-chates as potentially
toxic parameters. AOX in landfill leachate was within the range <10–2200 μg Cl/l, and AOXFP was within 51–15 000 μg Cl/l.
AOX and AOXFP correlated with chemical oxygen demand (COD). AOX discharge from closed landfills was generally lower than that
from operating landfills. The molar ratio of AOXFP/total organic carbon (TOC) suggested that organic compounds in a leachate
have a double bond every 15–190 carbons under the supposition that one chlorine would add to one double bond. The five landfills
discharging high-level AOXFP (>4000 μg Cl/l) were all landfills where sludge had been dumped. The removal efficiencies of
three parameters through leachate treatment processes were as follows: polychlorinated dibenzo-dioxins/dibenzo-furans (PCDDs/DFs)
> TOC > AOX. PCDDs/DFs were substantially removed at p.p.t. levels, while AOX was hardly removed at relatively low levels.
Received: February 14, 2000 / Accepted: January 9, 2001 相似文献
10.
Akiko Furuno Hiroaki Terada Masamichi Chino Hiromi Yamazawa 《Atmospheric environment (Oxford, England : 1994)》2004,38(40):6989
Japan Atomic Energy Research Institute has developed an emergency response system WSPEEDI to forecast long-range atmospheric dispersions of radionuclides discharged into the atmosphere. The latest version of WSPEEDI consists of an atmospheric dynamic model MM5 for calculating meteorological fields and a particle random-walk model for atmospheric dispersion. The performance of WSPEEDI was evaluated by data obtained from a field tracer experiment over Europe (ETEX) in this paper. The model validation was done with respect to the following points: (1) the dependence of model accuracy on the temporal and spatial resolutions of the meteorological fields and (2) the superiority of an atmospheric dynamic model over a mass-consistent wind model. Regarding (1), it was shown that the calculation accuracy of the new version with high temporal resolution was improved, especially at the edge of the plume. Moreover, although the increase in horizontal spatial resolution of the old version had no substantial effect on the model performance, increase in horizontal resolution of the new version contributed to the significant improvement of the calculation accuracy. These results showed that the dynamically calculated meteorological field with the spatial resolution of the meso-β–γ scale greatly improved calculation accuracy. 相似文献