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- Silicified microfossils from the Ediacaran Doushantuo Formation along a shelf margin-slope-basin transect in Hunan Province, South China, with stratigraphical implicationsOuyang, Qing; Zhou, Chuanming; Xiao, Shuhai; Wu, Chengxi; Chen, Zhe; Lang, Xianguo; Shi, Hongyi; Sun, Yunpeng (2025)Silicified microfossils are reported from nine stratigraphic sections of the Ediacaran Doushantuo Formation deposited in shelf margin, slope, and basin environments in Hunan Province of South China. These microfossils include sphaeromorphic and acanthomorphic acritarchs (15 genera and 29 species, including three new acanthomorph species, Bullatosphaera? colliformis n. sp., Eotylotopalla inflata n. sp., and Verrucosphaera? undulata n. sp.), multicellular algae, tubular microfossils, and other problematic forms, representing major fossil groups similar to those from the Doushantuo Formation in more proximal facies, e.g., inner shelf and shelf lagoon. A database of the abundance and occurrences of Doushantuo acanthomorphs is assembled and analyzed using quantitative and data visualization methods (i.e., rarefaction analysis, non-parametric multidimensional scaling, and network analysis). The results show that, at the genus- and species-level, taxonomic richness of Doushantuo acanthomorphs exhibits remarkable variation among facies, but this variation is largely due to sampling and taphonomic biases. The results also show that numerous acanthomorph taxa have broad facies distribution, affirming their biostratigraphic value. The analysis confirms that acanthomorphs in the Weng'an biota of shelf margin facies is transitional between Member II and Member III assemblages of shelf lagoon facies in the Yangtze Gorges area. The study shows the biostratigraphic potential of acanthomorphs in the establishment of regional biozones using the first appearance datum of widely distributed taxa, highlighting the importance of continuing exploration of undersampled Doushantuo sections in slope and basinal facies.
- Reply to commentariesToal, Gerard (Sage, 2024-09-26)The commentaries on my essay reveal the culture of debate on the Russia-Ukraine war. They also provide some evidence for the argument I sought to make. In this response I contextualize the original essay, sharpen its political implications, and engaging the commentaries. I conclude by addressing Ukraine’s seizure of Russian territory which reveals a shifting attitude toward negotiations and territory.
- On the Role of Uncertainty in Poisson Target Models Used for Placement of Spatial SensorsKim, Mingyu; Yetkin, Harun; Stilwell, Daniel J.; Jimenez, Jorge (SPIE, 2023-01-01)This paper addresses the role of uncertainty in spatial point-process models, such as those that might arise in modelling ship traffic. We consider a doubly stochastic Poisson point process where the intensity function is uncertain. To assess the role of uncertainty, we conduct a large set of numerical trials where we estimate a doubly stochastic Poisson point-process model from historical target data, and the evaluate the model by assessing the target detection performance of a set of sensors whose locations are selected using the model. Our work is motivated by seabed sensors that detect ship traffic, and we conduct numerical trials using historical ship traffic data near the mouth of the Chesapeake Bay, Virginia, USA, that was recorded by the Automated Identification System.
- From citizen social science to citizen bureaucraft: an ecology of social justice activism in SingaporeHaines, Monamie (SAGE Publications, 2024)This article theorizes citizen knowledge production from a non-Western, nonliberal locale by examining why social movement-oriented citizen science is not practiced in the soft authoritarian context of Singapore. While environmental injustice arguably does exist in the city-state, citizens and residents are nor responding by producing undone science. In fact, seldom does the environment, science, and technology figure as the object of activism, let alone social injustice claims. Drawing on interpretive documentary analysis of interviews, news reports and auto-ethnography, this article argues that science and technology are guarded by tacit “out-of-bound” markers—or OB markers that constitute the norms of acceptable criticism. These OB markers are socially maintained by, and coproduced alongside, the twinned practices of elitism and meritocracy in Singapore, where the academic elite constitute critical voices, and as such, must navigate their credibility and privilege with the state, thereby foreclosing more radical forms of activism. As a consequence, elite Singaporeans practice citizen social science in areas of the environment, race and migration. Further, I show their standards and practices of evidencing and scientific communication can be construed as ‘citizen bureaucraft,’ where they cite the state to hold a kintsugi mirror to injustices it perpetuates. This article describes an ecology of social justice activism centred on Singapore’s primarily Bangladeshi migrant construction workers during the pandemic to show how citizenship is coproduced with citizen knowledge production in more authoritarian contexts, and how the coercive state responds.