A preliminary report on new Ediacaran fossils from Iran

Vickers-Rich, P., Soleimani, S., Farjandi, F., Zand, M., Linnemann, U., Hofmann, M., Wilson, S.A., Cas, R. &; Rich, T.H. November, 2017. A preliminary report on new Ediacaran fossils from Iran. Alcheringa 42, 231–244. ISSN 0311-5518.

Recent exploratory field mapping of marine sedimentary sequences in the Koushk Mine locality of the Bafq region in Central Iran, and on the northern slopes of the Elborz Mountains south of the Caspian Sea, has yielded large complex body and trace fossils of Neoproterozoic–early Cambrian age. The recovered specimens resemble the previously documented Precambrian discoidal form Persimedusites, and a the tubular morphotype Corumbella, which is a novel occurrence for Iran and otherwise only recorded before from Brazil and the western USA. Additional enigmatic traces can not yet be interpreted unequivocally, but suggest that future work may uncover more unusual Ediacaran fossils from various localities in Central Iran.

Patricia Vickers-Rich* [prich@swin.edu.au, pat.rich@monash.edu], Faculty of Science, Swinburne University of Technology, Melbourne (Hawthorn), Victoria 3122, Australia; Sara Soleimani [sara_soleimani@yahoo.com], Palaeontology Department, Geological Survey of Iran, Tehran, Iran; Farnoosh Farjandi [farnooshfarjandi@gmail.com], Department of Geochemical Exploration, Geological Survey of Iran, Tehran, Iran; Mehdi Zand [zand.mehdi.geo@gmail.com], Geology Department, Bafq Mining Company, Koushk Mine, Yazd, Iran. Ulf Linnemann [ulf.linnemann@senckenberg.de], and Mandy Hofmann [mandy.hofmann@senckenberg.de], Senckenberg Naturhistorische Sammlungen, Dresden, Museum für Mineralogie und Geologie, Sektion Geochronologie, Koenigsbruecker Landstrasse 159, D-01109, Dresden, Germany; Siobhan A. Wilson [sasha.wilson@monash.edu], School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; Raymond Cas [ray.cas@monash.edu], School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; Thomas H. Rich? [trich@museum.vic.gov.au], Museum Victoria, Exhibition Gardens, PO Box 666, Melbourne, Victoria, 3001 Australia. *Also affiliated with: School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; School of Environmental Sciences, Deakin University, Melbourne (Burwood), Victoria, Australia 3125; Palaeontology Department, Museum Victoria, Carlton Gardens, PO Box 666, Melbourne, Victoria 3001, Australia. ?Also affiliated with: School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; Faculty of Science, Swinburne University of Science and Technology, Melbourne (Hawthorn), Victoria 3122, Australia.     

Cyclic Performance of an Elliptical-Shaped Damper with Shear Diaphragms in Chevron Braced Steel Frames

Several advantages of yielding dampers in controlling seismic energy have attracted the attention of many researchers in designing new buildings and retrofitting existing structures. In recent decades, various shapes and substances of such dampers have been used in engineering structures and their behavioral features, including the energy dissipating capacities, have been assessed. In this article, a novel method is presented to obtain the design relationship of two types of yielding elliptical dampers in terms of their selected geometric properties, i.e. distance between the shear diaphragms or virtual diameter and thickness. In addition, two different elliptical-shaped steel dampers equipped with the shear diaphragms are proposed and modeled using the finite element software ABAQUS and their performances are investigated. Then, 30 and 25 models, respectively, of the first and second types are studied using pushover analysis. The designed dampers considering the proposed relationships are used in two chevron braced steel frames placed between the bracing and the beam. Due to their desirable efficiency in energy dissipation and increase in the equivalent viscous damping of the frame, better efficiency is achieved in the modified damper with easier fabrication.     

Success(ion): Second-Generation Iranian Americans

More than a generation has passed since the substantial immigration of Iranians to the United States in the late 1970s, resulting in a sizable second-generation population (defined by convention as persons born in the United States and those who immigrated under the age of thirteen). This article presents a first look at the demographic and socioeconomic characteristics of the second generation at the national level, and compares them with those of the first generation (Iran- or foreign-born population). It uses the 2005–07 merged data set compiled by the United States Census in the American Community Survey (ACS). The results indicate a preliminary continuation of economic and educational success from the first- to the second-generation Iranians. Moreover, this achievement has become more balanced across gender lines in the second generation. Specifically, in terms of educational attainment and labor force participation, females have quickly closed the gap with their male counterparts. Because the second generation is still young, it is premature to assess the extent of intergenerational mobility among Iranians. But given this generation's initial achievements, one can only expect an upward trajectory.