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21.
80·2 Per cent of 111 Down syndrome pregnancies had amniotic fluid (AF) alpha fetoprotein (AFP) levels on or below the median and 10·8 per cent at or below 0·5 MoM compared with 41·9 and 1·4 per cent of controls. These differences were even more striking when the gestational age was < 18 weeks compared with ⩾ 18 weeks. No such association was seen for other chromosome abnormalities including trisomy 18,45,X and mosaics, 47,XXY, 47,XXX, and other structural abnormalities and triploidy, even when high levels due to defects such as omphalocele and cystic hygroma were excluded. All cases of trisomy 13 and 80 per cent with 47,XYY had AF-AFP levels above the median. Selection of cases for karyotyping by a low level of AF-AFP would clearly fail to detect aneuploidies other than Down syndrome and is not recommended. A possible weak association between low maternal serum (MS) and AF-AFPs in Down syndrome was most evident at < 18 weeks, suggesting that MS screening between 16 and 18 weeks may be the most informative time. 相似文献
22.
Ken’ichi Matsumoto Kaoru Tachiiri Michio Kawamiya 《Mitigation and Adaptation Strategies for Global Change》2018,23(1):1-26
Recent climate modeling studies have concluded that cumulative carbon emissions determine temperature increase, regardless of emission pathways. Accordingly, the optimal emission pathway can be determined from a socioeconomic standpoint. To access the path dependence of socioeconomic impacts for cumulative carbon emissions, we used a computable general equilibrium model to analyze impacts on major socioeconomic indicators on a global scale for 30–50 pathways with different emission reduction starting years, different subsequent emission pathways, and three different cumulative 2100 emission scenarios (emissions that meet the 2 °C target, the 2 °C target emissions plus 10 %, and emissions producing radiative forcing of 4.5 W/m2). The results show that even with identical cumulative emission figures, the resulting socioeconomic impacts vary by the pathway realized. For the United Nations 2 °C target, for example, (a) the 95 % confidence interval of cumulative global gross domestic product (GDP) is 1355–1363 trillion US dollars (2010–2100, discount rate = 5 %), (b) the cumulative GDP of pathways with later emission reduction starting years grows weaker (5 % significance level), and (c) emissions in 2100 have a moderate negative correlation with cumulative GDP. These results suggest that GDP loss is minimized with pathways with earlier emission reduction followed by more moderate reduction rates to achieve lower emission levels. Consequently, we suggest an early emission peak to meet the stringent target. In our model setting, it is desirable for emissions to peak by 2020 to reduce mitigation cost and by 2030 at the latest to meet the 2 °C target. 相似文献
23.
Tatsuro Nakaji Takuya Kobayashi Mihoko Kuroha Kumiko Omori Yuko Matsumoto Tetsushi Yonekura Katsuhiko Watanabe Jarkko Utriainen Takeshi Izuta 《Water, Air, & Soil Pollution: Focus》2004,4(2-3):277-287
To evaluate the effect of increasing nitrogen (N) deposition and tropospheric ozone (O3) concentrations on N-saturated forest ecosystems, we investigated the response of Japanese red pine (Pinus densiflora), an N-saturation sensitive tree species, to increasing N load under elevated O3 concentrations. One-year-old seedlings of red pine were treated with three levels of N supply (0, 50 and 100 mg N L-1 fresh soil volume) under two levels of atmospheric O3 concentration (< 5 and 60 ppb) for two growing seasons. Nitrogen treatment did not stimulate dry matter production of the seedlings. Growth inhibition was observed in the highest N treatment under low O3 and in the two higher N treatments under elevated O3. Irrespective of the O3 concentration, increasing N supply negatively affected root growth and mycorrhizal development in fine roots, resulting in a reduction in P and Mg uptake from the soil. Net photosynthetic rate was significantly reduced by both the highest N treatment under low O3 and the two higher N treatments under elevated O3, together with decreased N-availability to Rubisco. Nitrogen assimilated from NO3 - to amino acid in the needles was not affected by the treatments. However, needle protein concentration was reduced by the highest N-treatment under low O3 and by the two higher N-treatments under elevated O3. These results suggest that elevated O3 potentially disturbs the N-availability in the form of protein including Rubisco, and may advance the negative effects of excessive N-deposition on N-sensitive plant species in N-saturated forests. 相似文献
24.
The Influence of Synoptic-scale Air Flow and Local Circulation on the Dust Layer Height in the North of the Taklimakan Desert 总被引:1,自引:0,他引:1
Nobumitsu Tsunematsu Kenji Kai Takuya Matsumoto 《Water, Air, & Soil Pollution: Focus》2005,5(3-6):175-193
The present study investigates the influences of synoptic-scale air flows and local wind circulations on the dust layer height
(DLH) in the Taklimakan Desert, based on lidar observations performed in the north of the desert in March 2003. The DLH fluctuates
approximately every three days between 2500 m (above sea level) and 5000 m, including diurnal variations. Meteorological analyses
and numerical simulations show that the three-day fluctuation of DLH corresponds with variations in synoptic-scale air flows
over the Taklimakan Desert, and the diurnal variations are linked to downdrafts and updrafts that are formed over the north
of the desert as part of local circulations. When strong northerly winds prevail in the upper troposphere and a developed
valley wind blows toward the Tienshan Mountains in the lower troposphere, the downdrafts strengthen in the middle troposphere
over the north of the desert, lowering the DLH to about 2500 m. In contrast, the DLH rises to about 5000 m when the updrafts
develop between strong southerly winds in the upper troposphere and a developed mountain wind blowing from the Tienshan Mountains.
Simulations for the local circulation behavior without the presence of the Tienshan Mountains demonstrate that the valley
and mountain winds on the southern slope of the Tienshan Mountains control the intensity of the downdrafts and updrafts, thereby
influencing the DLH over the north of the Taklimakan Desert. 相似文献
25.
Shigeru Matsumoto 《Journal of Material Cycles and Waste Management》2018,20(4):2062-2067
Recycling is time consuming and the time available for housework may determine the intensity of recycling activities. In this study, we conducted a survey of 546 Japanese households and asked them their daily practice of five varieties of recycling activities: (1) choice of refill products, (2) use of own shopping bags, (3) sorting of recycled papers from burnable waste, (4) use of own drinking bottles when going out, and (5) use of recycle boxes prepared at the grocery store. We also asked households to record their behavior for two successive days. By combining recycling activity data and diary data, we estimate a multivariate probit model to empirically examine whether time available for housework determines the intensity of five varieties of recycling activities. The empirical result demonstrates that an individual that can allocate sufficient time for housework tends to purchase refill products. He or she also tends to bring their own shopping bags for grocery shopping. We also find that the size of house and the number of family members determine the likelihood of recycling. A housewife living with many family members in a large house is more likely to engage in time-consuming recycling activities. 相似文献
26.
Koji Yachiguchi Noriko Matsumoto Yuki Haga Motoharu Suzuki Chisato Matsumura Masahiro Tsurukawa Toshihiro Okuno Takeshi Nakano Kimi Kawabe Kei-ichiro Kitamura Akira Toriba Kazuichi Hayakawa Vishwajit S. Chowdhury Masato Endo Atsuhiko Chiba Toshio Sekiguchi Masaki Nakano Yoshiaki Tabuchi Takashi Kondo Shigehito Wada Hiroyuki Mishima Atsuhiko Hattori Nobuo Suzuki 《Environmental science and pollution research international》2014,21(10):6365-6372
To analyze the effect of polychlorinated biphenyl (PCB) 118 on fish bone metabolism, we examined osteoclastic and osteoblastic activities, as well as plasma calcium levels, in the scales of PCB (118)-injected goldfish. In addition, effect of PCB (118) on osteoclasts and osteoblasts was investigated in vitro. Immature goldfish, in which the endogenous effects of sex steroids are negligible, were used. PCB (118) was solubilized in dimethyl sulfoxide at a concentration of 10 ppm. At 1 and 2 days after PCB (118) injection (100 ng/g body weight), both osteoclastic and osteoblastic activities, and plasma calcium levels were measured. In an in vitro study, then, both osteoclastic and osteoblastic activities as well as each marker mRNA expression were examined. At 2 days, scale osteoclastic activity in PCB (118)-injected goldfish increased significantly, while osteoblastic activity did not change significantly. Corresponding to osteoclastic activity, plasma calcium levels increased significantly at 2 days after PCB (118) administration. Osteoclastic activation also occurred in the marker enzyme activities and mRNA expressions in vitro. Thus, we conclude that PCB (118) disrupts bone metabolism in goldfish both in vivo and in vitro experiments. 相似文献
27.
Haruhiro Ino Yoshihisa Matsumoto Ryo Takahashi Kazukiyo Takami Junya Nishino Masaaki Itoh 《Journal of Material Cycles and Waste Management》2008,10(2):129-133
H-ZSM-5 zeolite-supported gallium oxides were studied as aromatization catalysts for polyolefin pyrolysate. The catalysts
were prepared by a conventional physical mixing method with a gallium content of 1.0 and 4.5 wt% and were reduced in flowing
hydrogen at 585°C. To test their activity, a polyolefin sample was pyrolyzed and passed over a heated catalyst layer; the
product was analyzed by gas chromatography/mass spectrometry. A continuous-flow fixed-bed reactor was used for aromatization
of a model gas of polyolefin pyrolysate. For chlorine-free sources at 450°C, the catalyst with only 1.0 wt% gallium exhibited
activity comparable to a gallium silicate catalyst. For chlorine-contaminated sources, the catalyst with 4.5 wt% gallium sustained
catalytic activity for long periods. From the activity test results, it was found that zeolite-supported gallium catalysts
prepared by the physical mixing method are suitable for converting polyolefin into aromatic hydrocarbons. 相似文献
28.
Dioxin concentrations from municipal waste incinerators in Japan and elsewhere often show low concentrations that comply with legal limits (in this paper, the term "dioxin" designates WHO-TEQ: PCDD/Fs+dioxin-like PCB). However, such data is usually generated under normal steady state operational conditions, and there has been little investigation of releases occurring during startup and shutdown. It is important, therefore, to ascertain quantitatively emissions in an unsteady state (startup and shutdown) in order to correctly evaluate the relationship between emissions from a facility and the surrounding environment. The present study aimed to examine dioxin emissions of a continuously operated incinerator at startup and shutdown, and estimating the time period of greatest emission, and the processes causing dioxin generation. The startup process was divided into five stages and the shutdown into two; at each stage, dioxins in the flue gas were measured at the boiler outlet and the stack. From the concentration of dioxins and the flue gas volume at each stage, the amount of dioxins at startup and shutdown were calculated, and these were compared with that under steady state conditions. Dioxin concentration at the stack under steady state conditions was a very low level, while those at startup and shutdown were higher. In the case where dioxin concentration under a steady state is a low level like in this study, it is indicated that the total annual dioxin emission from a facility could be attributed to the startup periods. 相似文献
29.
Matsumoto Hiroshi Akinari Yugo Kaiso Kouji Kamimura Akio 《Journal of Material Cycles and Waste Management》2017,19(1):326-331
Journal of Material Cycles and Waste Management - Polyamide 66 was efficiently depolymerized and chemically converted by treatment with supercritical MeOH in the presence of glycolic acid. The... 相似文献
30.
Decomposition of aqueous monofluorophenols (MFPs) was investigated by contact glow discharge electrolysis (CGDE). During CGDE, both MFPs and the corresponding total organic carbon (TOC) in water were consumed smoothly, suggesting that carbon atoms of benzene nucleus could be eventually mineralized to inorganic carbon (IC). And all the fluorine atoms in the MFPs were equally converted to fluoride ions. Based on the primary intermediates from each starting materials, it showed that aromatic hydroxylation preferentially occurred at the para-or ortho-position to the phenolic OH group of each MFPs. The disappearance of both MFPs and TOC followed the first-order rate law. The apparent rate constants for the decay of MFPs were independent from the pKa values of MFPs. 相似文献