Root Uptake of Organic Contaminants into Plants: Species Differences

Trace amounts of xenobiotic organic contaminants have been frequently identified in the environment, including surface water and wastewater streams, and some are even in drinking water. The concern of unintended ingestion by humans or wildlife of such compounds resulting from the uptake by plants has risen in recent years. Although the uptake of a variety of xenobiotic organic contaminants by plants has been reported and the contaminants are found in the fruits in some cases, the differences between plant species are not fully understood. The emphasis of this research is to investigate the unique uptake ability of zucchini that has been reported repeatedly in recent years. Xylem saps, collected using a pressure chamber technique, were used to determine the values of Transpiration Stream Concentration Factor (TSCF), the ratio of the contaminant concentration in the xylem to that in the solution. Soybean hoyt, squash zephyr, and zucchini gold rush were used to compare the uptake ability of each plant. The root tissue was analyzed for total carbon and lipid content. Xylem sap was analyzed for total organic carbon and protein contents. The solubilities of the compounds in the xylem sap and deionized water were also determined using a modified shake flask method. From the measurement of TSCF, the uptake of hydrophobic contaminants in zucchini gold rush was found to be three-to tenfold of the other two plant species. The lipid content of the root tissue from zucchini gold rush was twice as much of that in soybean and squash zephyr, indicating enhanced adsorption of the hydrophobic compounds. The solubility of triclocarban in the xylem sap of zucchini gold rush was also twice the amount of that in soybean xylem sap. The enhanced solubility could be a result of high protein content measured in zucchini gold rush xylem sap, which may be increasing the facilitated transport of the hydrophobic compounds. The data generated in this study will be used to better understand the mechanistic differences associated with the plant uptake of organic contaminants by different species. This information can also be used in the selection of the plant species used in risk assessment studies and phytoremediation studies

メランコリー型うつ病に関わる脳機能結合と抗うつ薬による変化

広島大学(Hiroshima University)博士(医学)Doctor of Philosophy in Medical Sciencedoctora

Hyperlogarithms, Bernoulli多項式，および関連する多重ゼータ値

要約のみTohoku University大野泰生課

NEGOTIATION OF IDENTITY: (RE)CONSTRUCTION AND (RE)POSITIONING OF SELF THROUGH LANGUAGE LEARNING

Abstract: Becoming competent in a language involves more than just academic success, but also multi-faceted aspects of self in a situated context. The core of the study is to explore a participant’s experience as a marginalized student in a Filipino American community and the trajectories of learning a foreign language over time and space. Narratives from the participant reflect his approach toward language learning (LL) as well as his motivation behind language learning. This study highlights the impact of foreign language learning experience upon the participant’s conflict, negotiation, and transformation of identity. Following his positioning analysis, the paper closely looks at how evaluation by other Filipinos within the community contributes to the participant’s ongoing (re)construction and negotiation of identity. How these evaluations encourage or impede his access to heritage language and culture is analyzed based on the participant’s use of reported speech. The paper explored whether or not LL can be a way of negotiating and gaining agency, as well as how LL helps a marginalized learner to choose where and how he wants to belong to. The paper also looks at how marginalization motivates language learning, through which the participant seeks to reposition himself. The study also examines how power relationship (marginalized student in a situated context) plays a role in the process of negotiation of identity and meaning-making of self. Results from this study conclude that through experiences in foreign language learning as well as negotiating meanings for being a Japanese as a Foreign Language (JFL) student, the participant gradually shifts to belong to a different community prior to his language learning experience in which he can practice agency and is no longer a marginalized member of his heritage community

Fostering Tajik hydraulic development: examining the role of soft power in the case of the Rogun Dam

Basin riparians are not equally endowed in their resources and capacity to control water within a shared international river basin. Beyond hydrological constraints and geographical positions, other less tangible factors such as discourses and narratives influence interactions among basin riparians for water resources control and river basin development, requiring further analytical refinement of the role of power. The analysis of discursive and ideological dimensions of power, or 'soft' power, in particular, enables insights to strategies and tactics of water control under conditions of power asymmetries between basin states. This paper examines the debate around the controversial large-scale Rogun Dam project on the Vakhsh River in Tajikistan, exploring how the exercise of 'soft' power can, and sometimes cannot, shape transboundary water outcomes over water allocation. By focusing on international diplomacy and narratives, the paper provides insights into the noncoercive ways in which hydraulic development is justified. In particular, it is shown how 'soft' power was utilised by the Tajik decision-makers to legitimise dam development both at the international and domestic levels. The paper illustrates how, in the case of the Rogun Dam, 'soft' power falls short of determining a hydraulic development that changes the status quo of water allocation for Tajikistan