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Tin, secret societies, and the slow development of the Chinese mining community in a Siam-Burma border village of Maliwun, 1840s–1890s
Get PDFThis article reconstructs the mining practices and social activities of Chinese migrants in Maliwun, a tin-rich Burmese village on the Siam-Burma border between the 1840s and 1890s. Despite its natural resources and repeated mining attempts by various stakeholders, Maliwun could not materialise its potential and was slow in tin production and community development throughout this period. By focusing on the internal dynamics among its Chinese miners, especially around the rivalling Chinese “secret societies,” this article situates the frontier mining settlement within a larger regional network of the Southeast Asian Chinese and traces its Chinese community’s evolving relationships with fellow countrymen along the southern Siamese and northern Malayan coastlines. It argues that grassroots organisations played a crucial role in the early formation of this frontier Chinese migrant community, which was sitting at the intersection of political, labour, resource, gender, and ethnic frontiers and exhibited key features of fluid boundaries and transnational networks. Yet, these impacts should not be overstated, individually or collectively. The slow development of Maliwun calls for a careful reassessment of the limitation of roles played by porous borders, hybrid interactions, and transnational networks at a historic frontier.</p
QuTiP 5:The Quantum Toolbox in Python
No full textQuTiP, the Quantum Toolbox in Python (Johansson et al., 2012, Johansson et al., 2013), has been at the forefront of open-source quantum software for the past 13 years. It is used as a research, teaching, and industrial tool, and has been downloaded millions of times by users around the world. Here we introduce the latest developments in QuTiP v5, which are set to have a large impact on the future of QuTiP and enable it to be a modern, continuously developed and popular tool for another decade and more. We summarize the code design and fundamental data layer changes as well as efficiency improvements, new solvers, applications to quantum circuits with QuTiP-QIP, and new quantum control tools with QuTiP-QOC. Additional flexibility in the data layer underlying all “quantum objects” in QuTiP allows us to harness the power of state-of-the-art data formats and packages like JAX, CuPy, and more. We explain these new features with a series of both well-known and new examples. The code for these examples is available in a static form on GitHub (https://github.com/qutip/qutip-paper-v5-examples) and as continuously updated and documented notebooks in the qutip-tutorials package (https://github.com/qutip/qutip-tutorials).</p
Refining the timing of Middle Pleistocene ( MIS 12 to MIS 6) ice advances into northern central Europe:Sedimentological analysis and single‐grain luminescence dating of glaciotectonic complexes and tunnel‐valley fills
No full textThe timing of the Middle Pleistocene ice advances into northern central Europe is still disputed. In this study, we summarize the current state of knowledge on the age of the Middle Pleistocene Saalian and Elsterian ice advances into northern central Europe and provide new single‐grain luminescence ages of related meltwater deposits. Twenty‐five samples for luminescence dating were taken from five different Saalian ice‐marginal positions and (upthrusted) Elsterian tunnel‐valley fills in northern Germany. The sampled Elsterian deposits mainly comprise subaqueous fan and delta sediments, which were deposited in glacial lakes that formed in underfilled tunnel valleys and their marginal areas. The estimated luminescence ages range between >578 and 346±98 ka, probably correlating with Marine Isotope Stage (MIS) 12, although an older and/or younger age (MIS >14 to MIS 8) cannot be excluded. During MIS 6, four different ice advances are recorded from the study area. During the maximum extent of the first and second Saalian Drenthe ice advances, large ice‐dammed lakes formed along the Fennoscandian ice sheets, which catastrophically drained during ice‐margin retreat. Further north, glaciofluvial fans and/or larger glaciofluvial distributive systems formed along the ice sheets. The first Saalian Drenthe ice advance probably occurred during MIS 6e‐d. However, the estimated luminescence ages range between 293±59 and 209±37 ka, and therefore, we cannot rule out an earlier Saalian pre‐Drenthe ice advance into the north‐eastern part of the study area. After a phase of ice‐sheet retreat, fluvial erosion and soil formation, the second Saalian Drenthe ice advance probably occurred during late MIS 6c. The estimated luminescence ages range between 172±38 and 123±18 ka. Meltwater deposits that are related to the third Saalian Drenthe (Hondsrug ice stream) and/or Warthe ice advances have luminescence ages of 128±19 to 123±22 ka, correlating with MIS 6b‐a. The glaciotectonic complexes partly have a multiphase development related to the different Saalian ice advances. Smaller composite ridge systems with shallow detachments (20–60 m deep) evolved in areas with tunnel‐valley fills, probably controlled by the rheological contrasts between sandy meltwater deposits and underlying fine‐grained deposits of the uppermost Elsterian tunnel‐valley fills (Lauenburg Clay Complex). In contrast, larger glaciotectonic complexes with deep detachments (>100 m deep) formed further south (‘Rehburg line’) where large tunnel valleys are absent
