A new apparatus for measuring elastic wave velocity and electrical conductivity of fluid‐saturated rocks at various confining and pore‐fluid pressures

Pore‐fluid pressure is a critical parameter that governs geodynamic processes including seismic activities. Its evaluation through geophysical observations provides us insights into these processes. The quantitative evaluation requires a thorough understanding of the influence of pore‐fluid pressure on geophysical parameters, such as seismic velocity and electrical conductivity. To study the influence of pore‐fluid pressure on these parameters, we have built a new apparatus with a pore‐fluid pressure control system, which is capable of simultaneously measuring elastic wave velocity and electrical conductivity. Our new apparatus employs two sets of plastic piston–cylinders for the electrical insulation and pore‐fluid pressure transmission. The pore fluid is electrically isolated from the metal work, and its pressure can be precisely controlled without significant contribution of the friction between the piston and cylinder. Our new apparatus was used for a simultaneous measurement of velocity and conductivity in a brine‐saturated Berea sandstone. Elastic wave velocity and electrical conductivity changed in response to the change in confining and pore‐fluid pressures, showing the usefulness of the new apparatus.     

Fluid chemistry in the Solitaire and Dodo hydrothermal fields of the Central Indian Ridge

Fluid chemistry and microbial community patterns in chimney habitats were investigated in two hydrothermal fields located at the Central Indian Ridge. Endmember hydrothermal fluid of the Solitaire field, located ~3 km away from the spreading center, was characterized by moderately high temperature (307°C), Cl depletion (489 mm ), mildly acidic pH (≥4.40), and low metal concentrations (Fe ≤ 105 μm and Mn = 78 μm ). Chloride depletion indicates that the subseafloor source fluid had undergone phase separation at temperatures higher than ~390°C while the metal depletion was likely attributable to fluid alteration occurring at a venting temperature of around 307°C. These different temperature conditions suggested from fluid chemistry might be associated with an off‐spreading center location of the field that allows subseafloor fluid cooling prior to seafloor discharge. The microbial community in the chimney habitat seemed comparable to previously known patterns in typical basalt‐hosted hydrothermal systems. Endmember hydrothermal fluid of the Dodo field, standing on center of the spreading axis, was characterized by high H₂ concentration of 2.7 mm . The H₂ enrichment was likely attributable to fresh basalt–fluid interaction, as suggested by the nondeformed sheet lava flow expansion around the vents. Thermodynamic calculation of the reducing pyrite–pyrrhotite–magnetite (PPM) redox buffer indeed reproduced the H₂ enrichment. The quantitative cultivation test revealed that the microbial community associated with the hydrothermal fluid hosted abundant populations of (hyper)thermophilic hydrogenotrophic chemolithoautotrophs such as methanogens. The function of subseafloor hydrogenotrophic methanogenic populations dwelling around the H₂‐enriched hydrothermal fluid flows was also inferred from the ¹³C‐ and D‐depleted signature of CH₄ in the collected fluids. It was observed that the hydrothermal activity of the Dodo field had ceased until 2013.     

Shi‘ite Women's Seminaries (howzeh-ye ‘elmiyyeh-ye khahran) in Iran: Possibilities and Limitations

The establishment of Jami‘at al-Zahra, the first official female seminary in post-revolutionary Iran, opened new possibilities for women to enter the male-dominated clerical hierarchy. The rapid growth of female seminaries increased the presence of seminary-educated women in the official religious sphere. However, as opposed to the male seminaries whose dominant role is to train mojtaheds who can issue a competent legal opinion, the primary role of female seminaries is to train educators and propagandists. Drawing on interviews, documents issued by seminaries and secondary sources, this paper concludes that in spite of the rapid growth of female seminaries, very few women reach the rank of a mojtahed, and thus, in no way weaken the male-centric seminary system in contemporary Iran.     

关于北京城的风水与环境

本文以一位社会人类学家的眼光对北京城的都市风水与环境评价过程作了研究。指出,北京城虽然是按照《周礼·考工记》而设计建造的中国都城的典范,但透过"八臂毗沙门天城"的神话的表象,可窥视北京城的规划强调的是与周围环境相适应的准则。通过风水思想与神话,我们深知都市建设中环境意识的重要。     

Women's translations of scientific texts in the 18th century: a case study of Marie-Anne Lavoisier

In the 18th century, many outstanding translations of scientific texts were done by women. These women were important mediators of science. However, I would like to raise the issue that the 'selection,' which is the process by which intellectual women chose to conduct translation works, and those 'selections' made by male translators, would not be made at the same level. For example, émilie du Chatelet (1706-1749), the only French translator of Newton's "Principia," admitted her role as participating in important work, but, still, she was not perfectly satisfied with the position. For du Chatelet, the role as a translator was only an option under the current conditions that a female was denied the right to be a creator by society. In the case of Marie-Anne Lavoisier (1743-1794), like du Chatelet, we find an acute feeling in her mind that translation was not the work of creators. Because of her respect toward creative geniuses and her knowledge about the practical situation and concrete results of scientific studies, the translation works done by Marie-Anne Lavoisier were excellent. At the same time, the source of this excellence appears paradoxical at a glance: this excellence of translation was related closely with her low self-estimation in the field of science. Hence, we should not forget the gender problem that is behind such translations of scientific works done by women in that era. Such a possibility was a ray of light that was grasped by females, the sign of a gender that was eliminated from the center of scientific study due to social systems and norms and one of the few valuable opportunities to let people know of her own existence in the field of science.     

Assessing the resilience of irrigation agriculture: applying a social-ecological model for understanding the mitigation of salinization

This paper creates and applies a computational model of irrigation agriculture in order to study the effects of salinization in Mesopotamia, with the model developed applicable to cases beyond that studied here. Scholars have long suspected that central and southern Mesopotamia present environments which limited agricultural production over the long-term. In regions such as central Mesopotamia, where salinization likely affected settlement and agriculture in different periods but was more manageable than in more southern regions, fallowing regimes, natural and engineered leaching, and decisions made on when to crop were strategies applied in order to limit the effects of salinization. In this paper, we assess the effectiveness of these coping strategies by incorporating projected climate, soil, and landscape conditions with agricultural practices. The simulation results not only demonstrate the effectiveness and limitations of inhibiting progressive salinization, but they can be compared with the archaeological record in order to determine if the results could reasonably be matched with past events and help to interpret settlement history.