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41.
Kohei Sakat Aya Sakaguchi Masaharu Tanimizu Yuichi Takaku Yuka Yokoyam Yoshio Takahashi 《环境科学学报(英文版)》2014,26(2):343-352
Sources of Pb pollution in the local atmosphere together with Pb species, major ions, and heavy metal concentrations in a size-fractionated aerosol sample from Higashi-Hiroshima(Japan) have been determined by X-ray absorption near-edge structure(XANES) spectroscopy, ion chromatography, and ICP-MS/AES, respectively. About 80% of total Pb was concentrated in fine aerosol particles. Lead species in the coarse aerosol particles were PbC2O4, 2PbCO3·Pb(OH)2, and Pb(NO3)2, whereas Pb species in the fine aerosol particles were PbC2O4, PbSO4, and Pb(NO3)2. Chemical speciation and abundance data suggested that the source of Pb in the fine aerosol particles was different from that of the coarse ones. The dominant sources of Pb in the fine aerosol particles were judged to be fly ash from a municipal solid waste incinerator and heavy oil combustion. For the coarse aerosol particles, road dust was considered to be the main Pb source. In addition to Pb species, elemental concentrations in the aerosols were also determined. The results suggested that Pb species in size-fractionated aerosols can be used to identify the origin of aerosol particles in the atmosphere as an alternative to Pb isotope ratio measurement. 相似文献
42.
Bees are important pollinators for many flowering plants. Female bees are thought to be more effective pollinators than male
bees because they carry much more pollen than males. Males of some solitary bee species are known to patrol near flowers that
females visit. Because patrolling males visit flowers to mate or defend their territories, they may function as pollinators.
However, the significance of patrolling males to pollination has not been studied. We studied males of a solitary bee, Heriades fulvohispidus (Megachilidae), patrolling near flowers and visiting flowers that attracted nectar-feeding insects, including conspecifics,
on the Ogasawara (Bonin) Islands. To test the hypothesis that patrolling male bees may function as pollen vectors, we compared
the frequency of visits by H. fulvohispidus to flowers of an endemic plant, Schima mertensiana (Theaceae); comparisons were made among flowers with a dead H. fulvohispidus, a dead beetle, a piece of plastic, and nothing (control flowers). Patrolling H. fulvohispidus more frequently visited flowers with a dead conspecific, a dead beetle, or a piece of plastic than the control flowers. Our
experiment demonstrates that nectar-feeding insects (including conspecifics and other insects) enhance the flower-visiting
frequency of patrolling H. fulvohispidus males on S. mertensiana flowers. Furthermore, we observed S. mertensiana pollen on patrolling males as well as females, suggesting that male bees may also function as pollen vectors. 相似文献
43.
CO<Subscript>2</Subscript> emission and economic growth of Iran 总被引:1,自引:0,他引:1
Amin Yousefi-Sahzabi Kyuro Sasaki Hossein Yousefi Yuichi Sugai 《Mitigation and Adaptation Strategies for Global Change》2011,16(1):63-82
This research investigates the relationship between CO2 emission and economic growth of Iran over 14 years from 1994 to 2007 using a national panel data set. The statistical and
emission intensity methodologies are used for analyzing the data series. The study finds evidence supporting parameters which
conclude the stability of significant correlation between CO2 emission and economic development over time during the years under investigation in Iran. This relationship is investigated
and discussed for the energy sectors of the country as well. The results confirm that in all sectors except of agricultural,
there is a positive strong correlation between CO2 emission and economic growth throughout the study period. In most sectors, CO2 emission intensity (the emission per unit of GDP) doesn’t show increasing trends while the absolute emission is rapidly increasing
by the economic growth. 相似文献
44.
This paper reports on the relationships between creative mental sets and rule-violating actions using questionnaires answered by 218 nursing workers. An exploratory factor analysis was conducted. The results revealed five factors of creative mental sets: curiosity, minutiae, inquiry, sensitivity, and courage. In addition, rule-violating actions were found to consist of three factors: violation of regulations, violation of local rules, and self-style. The results of multiple regression analyses showed a negative relation between curiosity and regular rule violation. Negative correlations were observed among minutiae, inquiry, and local rule violation. Furthermore, the mean score of local rule violation of a person who thinks that it is important for the work environment to offer high and excellent care is significantly higher than that of those who think that other environmental considerations are more important. The result elucidated the necessity of using workers’ heuristics in the process of improving safety rules as well as improving their acceptability to workers. This point is important and applicable not only in the field of patient safety management systems, but also in other fields. 相似文献
45.
Reiko Mitsuya Yuichi Ebine Manami Nozaki Kageyu Noro 《International journal of occupational safety and ergonomics》2013,19(4):393-403
This paper introduces preventive measures against Deep Vein Thrombosis (DVT) during Visual Display Units (VDU) work. Four experiments were conducted in order to address this issue. The effectiveness of the preventative measures was evaluated by measuring foot swelling. The results indicated that the following 3 methods would be particularly effective: (a) occasionally adopting a reclining posture with a footrest, (b) 10-min walking every 50-60 min of VDU work, and (3) stretching. In addition we predicted that taking a deep breath could sometimes be effective. DVT is likely to occur in daily life and its incidence can be related to the long-term postures associated with VDU work. This paper suggests that VDU workers should be aware of the risk of DVT and take preventative measures. 相似文献
46.
Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and coplanar biphenyls (Co-PCBs) were determined in Japanese human adipose tissues. Temporal trends were assessed by comparing data collected during 1970-1971, 1994-1996 and 2000. Mean TEQ levels of PCDD/Fs in human adipose tissue showed a significant decrease from 31.6 +/- 9.2 pg-TEQ/g fat wt in 1970-1971 to 11.9 +/- 7.4 pg-TEQ/g fat wt in 2000, and coplanar PCBs decreased from 35.4 +/- 21.9 pg-TEQ/g fat wt in 1970-1971 to 15.3 +/- 8.2 pg-TEQ/g fat wt in 2000. However, some PCB congener concentrations did not change during this time. A comparison of data using the latest PCB-TEQ showed no significant changes. Therefore, research on source characterization and monitoring of short-term temporal trends on these compounds should be carried out continuously. 相似文献
47.
Guido Plaza Hideo Sakaji Hitoshi Honda Yuichi Hirota Kazuya Nashida 《Marine Biology》2007,152(5):1051-1064
Spawning pattern (assessed by seasonal changes in ovarian developmental stages) and type of fecundity (assessed by analysis
of oocyte-size frequency distributions) of the round herring Etrumeus teres were studied in relation to ovarian growth and seasonal changes in the gonadosomatic (GSI), hepatosomatic (HSI) and liposomatic
(LSI) index as well as the somatic condition of spawners (CS) in a spawning ground of southern Japan. Except for summer, mature
and recently spawned ovaries occurred all year round. Oogonia and primary oocytes were present in all ovaries, and cortical
alveoli stage (CA) oocytes occurred in all mature, hydrated and partially spent (PS) females (PS: females containing post-ovulatory
follicles). Before hydration, a clutch of larger yolked oocytes, undergoing synchronous growth (range 0.7–1.1 mm), was present
in mature ovaries which was completely separated from a more heterogeneous clutch of oogonia, primary and secondary oocytes
(<0.150 mm) and oocytes in the CA stage (range 0.15–0.60 mm). As vitellogenesis progressed, the yolked clutch increased in
size but the CA oocytes remained arrested. The latter entered into the secondary growth phase when hydration started in the
advanced batch. Ovarian growth was isometric in all developmental stages, validating the use of GSI, which showed a consistent
monthly evolution among years. Spawning stopped in summer (July and August) and peaked in winter and spring. HSI correlated
positively with GSI on both a monthly mean basis (r = 0.76) and individual fish basis (liver weight explained 67–83% of the variability in ovary weight when females were grouped
into 1-unit GSI intervals) suggesting a significant role of liver in vitellogenesis. LSI and CS also showed marked seasonal
changes peaking from summer to middle autumn. Overall results suggest that E. teres is a multiple spawner with a group-synchronous ovarian development and indeterminate annual fecundity, with the three processes
linked to an isometric growth of the ovary. We propose that such a reproductive pattern is an adaptation to produce batches
of large pelagic eggs through a protracted spawning season. 相似文献
48.
Atsushi Terazono Yuichi Moriguchi Shin-ichi Sakai Hiroshi Takatsuki 《Journal of Material Cycles and Waste Management》2000,2(2):80-88
This study evaluated the environmental impacts of sprayed-on asbestos, which had been used as insulation material in buildings,
from multiple perspectives, mainly at the disposal stage. The health risks from asbestos emission and energy consumption were
estimated. Two disposal scenarios were assumed for the asbestos: melting for reduced-risk disposal and ordinary packaging/landfilling.
We estimated the asbestos emission and health risk in the case of packaging/landfilling, assuming uncontrolled management
of the landfill site. A difficulty with introducing health-risk concepts into life cycle assessment (LCA) is the pulse–flux
problem, which is discussed in the light of these estimations. In order to solve this problem, we proposed a method using
a conversion factor representing exposure-dose/emission, and showed that emission could be converted into health risk. We
also estimated the energy consumption for melting asbestos in the disposal stage, which can decrease the health risk. If we
consider the energy consumption for the life cycle of asbestos, only a little energy is required for melting, compared with
the large amount of energy saved in the use stage owing to the insulating effect of the asbestos. The trade-off relationship
between health risk and energy consumption for the disposal scenarios indicated the need for weighting methods to handle trade-offs
such as this.
Received: July 2, 1998 / Accepted: December 20, 1999 相似文献
49.
Hidenao Hasegawa Hirofumi Tsukada Hitoshi Kawabata Yuki Chikuchi Yuichi Takaku Shun'ichi Hisamatsu 《Journal of environmental radioactivity》2009
Direct deposition of radioactive material onto crops is one important pathway for safety assessment of radionuclides released from nuclear facilities. Foliar uptake of Cs by radish (Raphanus sativus L. cv. Redchim) was studied by applying droplets of Cs solution (CsCl or CsNO3) on an upper leaf surface. The uptake of Cs was strongly affected by counter anions of Cs in the applied solution. Approximately 80% of Cs was absorbed for CsCl solution, while only 20% was absorbed for CsNO3. The partition of absorbed Cs between leaf and root tuber was quite similar for both Cs compounds, which indicated that behavior of the absorbed Cs in radish was the same for both. 相似文献
50.
PCDDs and PCDFs in vehicle exhaust particles in Japan. 总被引:6,自引:0,他引:6
Vehicle exhaust particles from gasoline and diesel engine cars were analyzed for PCDDs and PCDFs. The congener patterns of PCDDs and PCDFs in exhaust particles were different between gasoline and diesel engine cars. Suspended particulate matter from electrostatic precipitator connected to a highway tunnel was also analyzed for PCDDs and PCDFs. The congener pattern of suspended particular matter was different from both of gasoline and diesel engine cars. Total amounts of PCDDs/PCDFs sum concentrations in gasoline, diesel and suspended particulate matter were 0.21, 0.87 and 26.0 ng/g, respectively. The I-TEQs levels in gasoline, diesel and suspended particulate matter were 4.2, 11 and 242 pg/g, respectively. 相似文献