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It is easy to get lost in the vast amount of knowledge that is currently produced. In this study, to get a comprehensive picture
of current scientific knowledge about global warming issues, we developed a mapping framework for global warming research
based on the relationships between nature and human society. The mapping includes seven phases: (1) socioeconomic activity
and greenhouse gas emissions, (2) carbon cycle and carbon concentration, (3) climate change and global warming, (4) impacts
on ecosystems and human society, (5) adaptation, (6) mitigation, and (7) social systems. We applied the findings of the Intergovernmental Panel on Climate Change Fourth Assessment Report to the mapping. The quantity of research results and their reliability were analyzed on the basis of expert judgment to better
understand the extent to which current scientific knowledge provides answers to society’s major concerns. The quantity and
reliability of answers have increased in phases 2 and 3 relative to research in the Third Assessment Report. Although a large quantity of results have been produced in phases 4 and 6, they are not always sufficient. More studies
are required in phases 1, 5, and 7, and the reliability of existing knowledge needs to be improved in these phases. Mapping
global warming issues enabled us to visually comprehend the numerous and varied parts of global warming research as a whole
and to discern gaps in knowledge and other research shortfalls.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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The toxicity and bioaccumulation of two heavy metals—lead (Pb) and cadmium (Cd)—in a semi-aquatic plant, Colocasia esculenta (L. Schott), from a synthetic heavy metal solution were studied. Young plants of equal size were grown hydroponically in shallow raceways containing Hoagland medium amended with 20, 40, and 60 mg l?1 of Pb and 2, 4, and 6 mg l?1 of Cd. The medium containing heavy metals was allowed to flow through the raceways with a change in influent heavy metal solution on every 5th day. The experiment was continued for 20 days. A set of control raceways—one comprised of nutrient medium with heavy metal supplements, devoid of plants, and another with the plants and nutrient medium having no metal supplement—was also simultaneously run. Chlorosis in the leaves was the prominent toxicity symptom observed due to Pb and Cd on the test plants. A significant decrease in the relative growth, biomass productivity, and total chlorophyll content were noticed in the plants with an increase in concentration of metal supplement in the solution and exposure time. Both metals accumulated to higher concentrations in the roots than in shoots, suggesting that the metals were bound to the root cells and their translocation to the leaves was limited. The results of the 20-day-long experiments indicate that from a phytoremediation perspective, C. esculenta is a promising plant species for remediation of wastewater polluted with lower concentrations of Pb and Cd. 相似文献
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Data were tabulated and compared for cases involving prenatal diagnostic procedures performed in the 8 years between January 1985 and December 1992. Of a total of 2781 pregnancies, 2546 cases (91·5 per cent) were diagnosed by amniocentesis, and 235 (8·5 per cent) by chorionic villus sampling (CVS). These findings reflect the fact that amniocentesis has taken deep root as the prenatal diagnostic procedure widely acknowledged by society, whereas even the existence of CVS has yet to be generally recognized. Analysis of our clinical and laboratory results and complication rates, however, suggests that CVS is a safe and accurate alternative to amniocentesis which should and can be positively presented to all patients who are candidates for prenatal diagnosis. 相似文献
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Sachi Taniyasu Nobuyoshi Yamashita Eriko Yamazaki Gert Petrick Kurunthachalam Kannan 《Chemosphere》2013,90(5):1686-1692
A field study on the photolysis of perfluoroalkyl substances (PFASs) was conducted at high altitudes in Mt. Mauna Kea (Hawaii, USA; 4200 m) and Mt. Tateyama (Toyama, Japan; 2500 m). Results of photolysis of PFASs in the field were further confirmed in laboratory studies. Perfluorooctanesulfonate (PFOS), which is perceived as a non-degradable chemical in the environment, can undergo photolysis. Long chain PFASs can be successively dealkylated to short chain compounds such as perfluorobutyric acid (PFBA) and perfluorobutane sulfonate (PFBS), but the short chain compounds were relatively more resistant to photodegradation. These results suggest that environmental levels of short chain PFASs would increase both due to their formation from photolysis of long chain PFASs and from direct releases. Earlier studies on photolysis of PFASs were focused on the formation of perfluorocarboxylic acids (PFCAs) and perfluorosulfonic acids (PFSAs) from precursor compounds (such as fluorotelomer alcohols) under laboratory conditions. Our study suggests that PFSAs and PFCAs themselves can undergo photodegradation in the environment. 相似文献
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Hiroaki Naoe Shuichi Hasegawa Jost Heintzenberg Kikuo Okada Akihiro Uchiyama Yuji Zaizen Eriko Kobayashi Akihiro Yamazaki 《Atmospheric environment (Oxford, England : 1994)》2009,43(6):1296-1301
The state of mixture of light-absorbing carbonaceous particles was investigated in relation to light absorption properties using electron microscopic examinations, black carbon (BC) analyses of quartz filter by thermal/optical reflectance (TOR) method, measurements with two continuous light-absorbing photometers at a suburban site of Tsukuba, about 60 km northeast of Tokyo. The volume fraction of water-soluble material (?) in individual particles is important for assessing particulate light-absorbing and/or scattering of atmospheric aerosols. The values of ? in BC particles were evaluated by electron micrographs before and after dialysis (extraction) of water-soluble material. The mass absorption coefficient (MAC in units of m2 g?1) tended to increase with increasing the average ? in BC particles with the radius range of 0.05–0.5 μm. Thus, our results indicate that coatings of water-soluble material around BC particles can enhance the absorption of solar radiation. Moreover, the single scattering albedo (SSA) will increase because a large amount of coating material will scatter more light. 相似文献
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Some kinds of amine groups can be introduced to the glassy carbon surface by the electrode oxidation of the carbon electrode surface in ammonium carbamate solution, and this amine groups modified electrode is named as an aminated glassy carbon electrode. The existences of not only primary amine but also secondary and tertially amines were confirmed by X ray photoelectron spectroscopy. The applications of the aminated carbon material for the electrocatalytic reductions of oxygen, hydrogen peroxide, and organic compounds such as quinones were carried out, and the effects of amination on the formation of electrocatalytic sites for many species were revealed. The electrocatalyzed cyclic voltammograms of metal ions and metal chelate compounds obtained by aminated glassy carbon electrodes are also discussed. Moreover, we intend to describe that the aminated carbon electrode can exhibit the large reduction waves of inorganic oxoacids such as N02? or bromide ion. The introduced functional groups containing nitrogen atom can change the distribution of the electron densities of the graphite carbon surface, and this specific electron distribution environment may generate the various electrocatalytic activities. 相似文献
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Pun Vivian C. Dowling Russell Mehta Sumi 《Environmental science and pollution research international》2021,28(21):26404-26412
Environmental Science and Pollution Research - Stunting is an important risk factor for early growth and health implications throughout the life course, yet until recently, studies have rarely... 相似文献
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T. Yamaguchi H. Nagano R. Murai H. Sugimori C. Sekiguchi I. Sumi 《Journal of Material Cycles and Waste Management》2018,20(4):1909-1917
High-purity Mn is necessary for high strength steel production. However, the availability of metal Mn is limited to a few countries. Therefore, as an alternative to direct purchasing of metal Mn, a process for Mn recovery was investigated. Waste dry cell batteries are considered to be one of the most feasible Mn sources. We have developed a high efficiency chemical separation system. This system consists of a three-phase chemical treatment. In the first phase, the metal components of the waste dry cell batteries were dissolved by acid, along with a reducing agent. Afterward, the undissolved carbon particles were separated by filtration. In the second phase, the dissolved Mn was selectively precipitated as manganese oxide by O3 oxidation. Then, the precipitated manganese oxide was separated from the other metal components by filtration. Finally, in the third phase, the manganese oxide was reduced to high-purity Mn using an electric furnace. 相似文献
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