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Gonadal sex steroid hormones are the principal factors that directly control the gonadal and morphological alterations during sex change in hermaphrodite fish; however, the physiological mechanism of action by which these hormones govern body coloration is poorly understood. The protogynous wrasse Pseudolabrus sieboldi is a good model for understanding the physiological mechanisms of gonadal and body color change during sex change in hermaphrodite fish. To obtain information on the relationship between sex steroids and body color change during the process of gonadal sex change, we analyzed body color, gonadal histology, and serum levels of sex steroids. Body color was analyzed using a quantitative analytical method based on the hue value. Compared to other body parts of the fish, the anal fin changed color the most, becoming increasingly redder in association with gonadal changes that converted ovaries to testes. Levels of serum 11-ketotestosterone (11KT) increased as the gonadal sex change proceeded, whereas no significant change was observed in estradiol-17β (E2) levels. Moreover, we found a significant correlation between the hue value of the anal fin and serum 11KT levels, but not E2 levels. These results suggest that androgen, but not estrogen, plays a principle role in the changes in both gonadal morphology and body color in the transformation from female to male in this species. To our knowledge, this is the first quantitative demonstration of the relationship between body color and serum steroid levels during sex change in fish.  相似文献   
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Co-integration theory has been employed in this paper and Granger causes are found between urbanization rate and GDP, between capital stock and GDP. Scenario analysis of GDP is performed using the GDP model established in the paper. The energy consumptions in Germany, Japan and other developed countries are analyzed and compared with the energy consumption in China. Environmental friendly scenario of energy demand and CO2 emissions for sustainable China has been formed based on the results of comparison. Under environmental friendly scenario, the primary energy consumption will be 4.31 billion ton coal equivalence (tee) and CO2 emissions will be 1.854 billion t-c in 2050; energy per capital will be 3.06 tee that is 1.8 times of energy consumed in 2005 in China and 51% of consumed energy per capital in Japan in 2003. In 2050, the energy requirement of unit GDP will be 20% lower than that of Germany in 2003, but will be still 37% higher than that in Japan in 2003. It is certain that to fulfill the environmental friendly Scenario of energy demand and CO2 emissions is a difficult task and it needs long term efforts of the whole society, not only in production sectors but also in service and household sectors,  相似文献   
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Alkaline eluate from municipal solid waste (MSW) incineration residue deposited in landfill alkalizes waste and soil layers. From the viewpoint of accelerating stability and preventing heavy metal elution, pH of the landfill layer (waste and daily cover soil) should be controlled. On the other hand, pH of leachate from existing MSW landfill sites is usually approximately neutral. One of the reasons is that daily cover soil can neutralize alkaline solution containing Ca2+ as cation. However, in landfill layer where various types of wastes and reactions should be taken into consideration, the ability to neutralize alkaline solutions other than Ca(OH)2 by soil should be evaluated. In this study, the neutralization capacities of various types of soils were measured using Ca(OH)2 and NaOH solutions. Each soil used in this study showed approximately the same capacity to neutralize both alkaline solutions of Ca(OH)2 and NaOH. The cation exchange capacity was less than 30% of the maximum alkali neutralization capacity obtained by the titration test. The mechanism of neutralization by the pH-dependent charge can explain the same neutralization capacities of the soils. Although further investigation on the neutralization capacity of the soils for alkaline substances other than NaOH is required, daily cover soil could serve as a buffer zone for alkaline leachates containing Ca(OH)2 or other alkaline substances.  相似文献   
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Solid phase high explosive (HE) residues from munitions detonation may be a persistent source of soil and groundwater contamination at military training ranges. Saturated soil column tests were conducted to observe the dissolution behavior of individual components (RDX, HMX, and TNT) from two HE formulations (Comp B and C4). HE particles dissolved readily, with higher velocities yielding higher dissolution rates, higher mass transfer coefficients, and lower effluent concentrations. Effluent concentrations were below solubility limits for all components at superficial velocities of 10-50 cm day(-1). Under continuous flow at 50 cm day(-1), RDX dissolution rates from Comp B and C4 were 34.6 and 97.6 microg h(-1) cm(-2) (based on initial RDX surface area), respectively, significantly lower than previously reported dissolution rates. Cycling between flow and no-flow conditions had a small effect on the dissolution rates and effluent concentrations; however, TNT dissolution from Comp B was enhanced under intermittent-flow conditions. A model that includes advection, dispersion, and film transfer resistance was developed to estimate the steady-state effluent concentrations.  相似文献   
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Recently, a demand for the reuse, recycling and reduction of waste has arisen. In the food industry, efforts are being made to recycle the waste produced and use resources more efficiently. However, some industrial food waste or recycled waste materials generate heat as a result of fermentation and oxidation, which leads to an increase in temperature during storage and transport, ultimately resulting in spontaneous ignition. In this study, we examined the fermentation and heat generation by soy sauce squeezing residue (SSSR) produced during the brewing of soy sauce and by the fish meal produced during the processing of fish residue. The objective of this study was to investigate the causes of fires using various heat analysis methods and to understand the processes of fermentation and oxidation of food industry waste that lead to spontaneous ignition.  相似文献   
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Biphenyl was found to be converted to mutagenic compounds by UV irradiation with a high-pressure mercury lamp in nitrate aqueous solution under neutral conditions. The mutagenicity of the reaction mixture increased in proportion to the nitrate ion concentration. The most mutagenic product was dinitro dihydroxy biphenyl, and the main products in this reaction were 2-hydroxy-3-nitrobiphenyl and 4-hydroxy-3-nitrobiphenyl.  相似文献   
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