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1.
This paper examines quantitatively the patterns of collaboration over geographical boundaries in the emerging field of sustainability
science by empirically analyzing the bibliometric data of scientific articles. The results indicate that an increasing number
of countries are engaged in research on sustainability, with the proportion of articles published through international collaboration
rising as well. The number of countries engaged in international collaboration on sustainability research has been increasing,
and the diversity of countries engaged in research collaboration beyond national borders is also increasing. The geographical
patterns of collaboration on sustainability show that research collaboration tends to be conducted between countries which
are geographically located closely, suggesting that communication and information exchange might be limited within the regional
clusters. The focused fields of research activities on sustainability are significantly different between countries, as each
country has its focused fields of research related to sustainability. The specialization of research activities is also observed
in international collaboration. While these patterns of international collaboration within regional clusters focusing on specific
fields could be effective in promoting the creation, transmission, and sharing of knowledge on sustainability utilizing the
already existing regional networks, they could pose a serious obstacle to collecting, exchanging, and integrating diverse
types of knowledge, especially when it is necessary to deal with problems involving large-scale complex interactions with
long-term implications, such as climate change. It would be of critical importance to establish inter-regional linkages by
devising appropriate institutional arrangements for global research collaboration on sustainability science. 相似文献
2.
Kristanti RA Kanbe M Hadibarata T Toyama T Tanaka Y Mori K 《Environmental science and pollution research international》2012,19(5):1852-1858
Introduction
The accelerated biodegradation of 3-nitrophenol (3-NP) in the rhizosphere of giant duckweed (Spirodela polyrrhiza) was investigated.Materials and methods
Biodegradation of 3-nitrophenol in the rhizosphere of a floating aquatic plant, S. polyrrhiza, was investigated by using three river water samples supplemented with 10?mg?l?1 of 3-NP. Isolation and enrichment culture of 3-NP-degrading bacteria were performed in basal salts medium containing 3-NP (50?mg?l?1). The isolated strains were physiologically and phylogenetically characterized by using an API20NE kit and 16S rRNA gene sequencing.Results and discussion
Accelerated removal of 3-NP (100%) was observed in river water samples with S. polyrrhiza compared with their removal in plant-free river water. Also, 3-NP persisted in an autoclaved solution with aseptic plants, suggesting that the accelerated 3-NP removal resulted largely from degradation by bacteria inhabiting the plant rather than from adsorption and uptake by the plant. We successfully isolated six and four strains of 3-NP-degrading bacteria from the roots of S. polyrrhiza and plant-free river water, respectively. Phylogenetic analysis based on 16S rRNA gene divided the 3-NP-degrading bacteria into two taxonomic groups: the genera Pseudomonas and Cupriavidus. The strains belonging to the genus Cupriavidus were only isolated from the roots of duckweed. All strains isolated from the roots utilized 3-NP (0.5?mM) as a sole carbon and energy source, indicating that they could have contributed to the accelerated degradation of 3-NP in the rhizosphere of S. polyrrhiza.Conclusions
The rhizoremediation using S. polyrrhiza and its rhizosphere bacteria can be an effective strategy for cleaning up the 3-NP-contaminated surface waters. 相似文献3.
The bumblebee Bombus terrestris is not only an effective pollinator, but also a potential invasive alien species outside its native range. Recently, nearly
30% of queens of the Japanese native species Bombus hypocrita sapporoensis and B. hypocrita hypocrita were estimated to copulate with B. terrestris males in the field, suggesting that indigenous bumblebees could be genetically deteriorated through hybrid production with
the introduced species. In this study, we evaluated hybrid production between the introduced B. terrestris and the indigenous B. hypocrita sapporoensis under laboratory conditions. The hatching rate of eggs derived from interspecific matings was 0% and 8.6% depending on the
direction of the cross, which was significantly lower than that from intraspecific matings of B. terrestris (76.9%) and B. hypocrita sapporoensis (78.9%). Genetic studies using microsatellite markers revealed that both haploid and diploid individuals were present in
the egg stage, whereas all hatched larvae were haploid. In addition, histological studies revealed that eggs derived from
interspecific matings terminated development 2 days after oviposition. These results strongly suggested that eggs derived
from interspecific matings are inviable due to post-mating isolation mechanisms. Mass release of exotic pollinators could
cause serious population declines of native bumblebee species. 相似文献
4.
Yuya Takuwa Tadao Matsumoto Kazuyuki Oshita Masaki Takaoka Shinsuke Morisawa Nobuo Takeda 《Journal of Material Cycles and Waste Management》2009,11(4):305-311
Because landfill gas (LFG) contains an abundance of methane, the utilization of LFG as a renewable energy source is becoming
popular in many countries. LFG, however, contains various trace constituents, some of which may pose problems during utilization.
For example, siloxanes and halogenated volatile organic compounds (VOCs) can cause difficulties when present in the fuel of
gas engines. In addition, many VOCs and mercury have harmful effects on human health, especially on the health of workers
at landfill sites and people living near the landfills. Energy recovery from LFG is expected to make great progress in the
near future, particularly in Asia, but we found little information on the trace constituents of LFG in this region. Therefore,
we sought to characterize the trace components in LFG generated in two landfill sites in China and one site in Japan, to determine
the typical concentrations of these trace components in LFG, and to compare their concentrations among landfill sites in Asia.
We concluded that the trace components in LFG at the sites studied were mainly siloxanes generated from sewage sludge and
harmful benzene, toluene, ethylbenzene, and xylene compounds from petroleum products. 相似文献
5.
Kazunori Yamada Tetsuya Tamura Yuya Azaki Ayumi Kashiwada Yoji Hata Katsuya Higashida Yukihiro Nakamura 《Journal of Polymers and the Environment》2009,17(2):95-102
In this study, melB tyrosinase was applied for enzymatic removal of linear and branched p-alkylphenols from aqueous solutions. First, systematic studies were carried out to estimate the effects of the process parameters such as the temperature, pH value, and enzyme dose on quinone conversion of p-cresol as a model phenol compound. A variety of p-alkylphenols were removed from aqueous solutions through the tyrosinase-catalyzed quinone conversion and subsequent nonenzymatic adsorption of quinone derivatives on chitosan beads at pH 6.0 and 30 °C under the optimum conditions determined for p-cresol. The % removal values of 98–100 were obtained for p-n-alkylphenols. Branched p-alkylphenols with a weak estrogenic activity containing 4-tert-butylphenol and 4-tert-pentylphenol, which underwent no quinone conversion by commercially available mushroom tyrosinase in the absence of H2O2, were also effectively removed by further increasing either the melB tyrosinase concentration or the amount of added chitosan beads. The present technique is much effective in the fact that a series of reactions rapidly progress under mild conditions and the chitosan beads can be readily separated from the reaction medium after the enzymatic treatment. 相似文献
6.
A simple system to evaluate the 222Rn (radon) exhalation rate from soil has been improved. A sampling cuvette of 2.1 L is placed so that it covers the targeted ground soil, and radon emanating from the soil accumulates within the cuvette for 24 h. Its internal radon concentration is measured by the combination of an activated charcoal (PICO-RAD) and a liquid scintillation counting system. This study shows variations of the conversion factor (CF: unit Bq m(-3)/cpm) of PICO-RAD. The range of CF due to temperature (10-30 degrees C) was between -21% and +69%, and this due to humidity (30-90%) was between 0% and -15%. Humidity and radon concentration in the cuvette covering soil tended to saturate in a few hours. The above information was used to correct the CF for the evaluation. The improved system shows high reliability and can be easily applied to natural environments. 相似文献
7.
Iwahana Yuki Ohbuchi Atsushi Koike Yuya Kitano Masaru Nakamura Toshihiro 《Journal of Material Cycles and Waste Management》2017,19(1):226-234
Journal of Material Cycles and Waste Management - The radioactive nuclides in the incinerator fly ashes from municipal solid waste sampled in June 2006 were analyzed with γ-ray spectrometry.... 相似文献
8.
Risky Ayu Kristanti Masahiro Kanbe Tadashi Toyam Yasuhiro Tanak Yueqin Tang Xiaolei Wu Kazuhiro Mori 《环境科学学报(英文版)》2012,24(5):800-807
We investigated the biodegradation of 2-nitrophenol (2-NP), 4-nitrophenol (4-NP), and 2,4-dinitrophenol (2,4-DNP) in the rhizosphere of Spirodela polyrrhiza plants by conducting degradation experiments with three river water samples supplemented with each nitrophenol (NP). We then isolated NP-degrading bacteria both from the S. polyrrhiza roots and from the river water. In the river water samples, removal of the three NP was accelerated in the presence of S. polyrrhiza plants. The three NPs persisted in an autoclaved solution with sterile plants suggests that NP removal was accelerated largely by bacterial NP biodegradation rather than by adsorption and uptake by the plants. We isolated 8 strains of NP-degrading bacteria: 6 strains from the S. polyrrhiza roots and 2 strains from river water without the plants. The 2-NP- and 2,4-DNP-degrading bacteria were isolated only from the S. polyrrhiza roots. The 4-NPdegrading bacteria different from those isolated from the river water samples were also found on S. polyrrhiza roots. The 2-NP- and 4-NP-degrading strains isolated from the roots utilized the corresponding NP (0.5 mmol/L) as the sole carbon and energy source. The 2,4-DNP-degrading strains isolated from the roots showed substantial 2,4-DNP-degrading activity, but the presence of other carbon and energy sources was required for their growth. The isolated NP-degrading bacteria from the roots must have contributed to the accelerated degradation of the three NPs in the rhizosphere of S. polyrrhiza. Our results suggested that rhizoremediation with S. polyrrhiza may be effective for NP-contaminated surface water. 相似文献
9.
Virgin female cabbage butterflies, Pieris rapae crucivora, accept and mate with courting males, whereas mated females reject them and assume the “mate refusal posture”. This study
tested whether the biogenic amines, serotonin (5HT), dopamine (DA), and octopamine (OA), were responsible for this change
in behavior. The results showed that 2–3-day-old virgin females fed with 5HT rejected courting males significantly more frequently
compared with controls fed on sucrose. In contrast, the proportions of courting males rejected by virgin females fed with
either DA or OA did not differ from sucrose-fed controls. Oral application of each amine resulted in significantly increased
levels of the amine applied (or its metabolite) in the brain. The results strongly suggest that 5HT or a 5HT metabolite may
be responsible for the post-mating change in behavioral response of 2–3-day-old virgin females to courting males. Similar
effects of 5HT treatment were observed in 6–8-day-old virgin females, but in this case the results were only marginally different
from the controls, suggesting that the effect may decline with increasing female age. 相似文献
10.
Yuya Kajikawa Junko Ohno Yoshiyuki Takeda Katsumori Matsushima Hiroshi Komiyama 《Sustainability Science》2007,2(2):221-231
Sustainability is an important concept for society, economics, and the environment, with thousands of research papers published
on the subject annually. As sustainability science becomes a distinctive research field, it is important to define sustainability
clearly and grasp the entire structure, current status, and future directions of sustainability science. This paper provides
an academic landscape of sustainability science by analyzing the citation network of papers published in academic journals.
A topological clustering method is used to detect the sub-domains of sustainability science. Results show the existence of
15 main research clusters: Agriculture, Fisheries, Ecological Economics, Forestry (agroforestry), Forestry (tropical rain
forest), Business, Tourism, Water, Forestry (biodiversity), Urban Planning, Rural Sociology, Energy, Health, Soil, and Wildlife.
Agriculture, Fisheries, Ecological Economics, and Forestry (agroforestry) clusters are predominant among these. The Energy
cluster is currently developing, as indicated by the age of papers in the cluster, although it has a relatively small number
of papers. These results are compared with those obtained by natural language processing. Education, Biotechnology, Medical,
Livestock, Climate Change, Welfare, and Livelihood clusters are uniquely extracted by natural language processing, because
they are common topics across clusters in the citation network. 相似文献