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Projecting Poseidon’s Trident: America’s East Asia and the shifting contours of 1950s post-war naval policy
© 2020, © 2020 Informa UK Limited, trading as Taylor & Francis Group. While the US obtained control of the seas in maritime East Asia after the dissolution of the Japanese empire in 1945, the Truman administration did not link its international security with maritime space in the immediate post-war period. The outbreak of the Korean War and the First Taiwan Strait Crisis drove the US to rethink the significance of international waters and gradually adopt a sea-oriented strategic command. This development altered the defence structure in Cold War East Asia and such perimeters of maritime defence remained in place until the US ended official relations with Taiwan in 1979.This research is funded by the Isaac Newton Trust and the Chiang Ching-Kuo Foundation. My work was also supported by the Japan Foundation, Academia Sinica (Taiwan), and John A. Adams ’71 Center for Military History and Strategic Analysis at Virginia Military Institute
A Bayesian Account of Generalist and Specialist Formation Under the Active Inference Framework
This paper offers a formal account of policy learning, or habitual behavioral optimization, under the framework of Active Inference. In this setting, habit formation becomes an autodidactic, experience-dependent process, based upon what the agent sees itself doing. We focus on the effect of environmental volatility on habit formation by simulating artificial agents operating in a partially observable Markov decision process. Specifically, we used a "two-step" maze paradigm, in which the agent has to decide whether to go left or right to secure a reward. We observe that in volatile environments with numerous reward locations, the agents learn to adopt a generalist strategy, never forming a strong habitual behavior for any preferred maze direction. Conversely, in conservative or static environments, agents adopt a specialist strategy; forming strong preferences for policies that result in approach to a small number of previously-observed reward locations. The pros and cons of the two strategies are tested and discussed. In general, specialization offers greater benefits, but only when contingencies are conserved over time. We consider the implications of this formal (Active Inference) account of policy learning for understanding the relationship between specialization and habit formation
Geochronology and geochemistry of the c. 80 Ma Rutog granitic pluton, northwestern Tibet: Implications for the tectonic evolution of the Lhasa Terrane
The Rutog granitic pluton lies in the Gangdese magmatic arc in the westernmost part of the Lhasa Terrane, NW Tibet, and has SHRIMP zircon U-Pb ages of c. 80 Ma. The pluton consists of granodiorite and monzogranite with SiO2 ranging from 62 to 72 wt% and Al2 O3 from 15 to 17 wt%. The rocks contain 2.33-4.93 wt% K2O and 3.42-5.52 wt% Na2O and have Na2O/K2O ratios of 0.74-2.00. Their chondrite-normalized rare earth element (REE) patterns are enriched in LREE ((La/Yb)n = 15 to 26) and do not show significant Eu anomalies (αEu = 0.68-1.15). On a primitive mantle-normalized trace element diagram, the rocks are rich in large ion lithophile elements (LILE) and poor in high field strength elements (HFSE), HREE and Y. Their Sr/Y ratios range from 15 to 78 with an average of 30. The rocks have constant initial 87Sr/86Sr ratios (0.7045 to 0.7049) and slightly positive εNd(t) values (+0.1 to +2.3), similar to I-type granites generated in an arc setting. The geochemistry of the Rutog pluton is best explained by partial melting of a thickened continental crust, triggered by underplating of basaltic magmas in a mantle wedge. The formation of the Rutog pluton suggests flat subduction of the Neo-Tethyan oceanic lithosphere from the south. Crustal thickening may have occurred in the Late Cretaceous prior to the India-Asia collision. © Cambridge University Press 2008.published_or_final_versio
Defect formation and annealing behaviors of fluorine-implanted GaN layers revealed by positron annihilation spectroscopy
Defect formation and annealing behaviors of fluorine-implanted, unintentionally doped GaN layers were studied by positron annihilation spectroscopy (PAS). Single Ga vacancies (VGa) were identified as the main vacancy-type defects detected by PAS after fluorine implantation at 180 keV with a dose of 1× 10 15 cm -2. Implantation-induced VGa tend to aggregate and form vacancy clusters after postimplantation annealing in N 2 ambient at 600 °C. Fluorine ions tend to form F-vacancy complexes quickly after thermal annealing, which is consistent with the proposed diffusion model that predicts the behaviors of fluorine in GaN. © 2009 American Institute of Physics.published_or_final_versio
A procedure for the change point problem in parametric models based on phi-divergence test-statistics
This paper studies the change point problem for a general parametric,
univariate or multivariate family of distributions. An information theoretic
procedure is developed which is based on general divergence measures for
testing the hypothesis of the existence of a change. For comparing the accuracy
of the new test-statistic a simulation study is performed for the special case
of a univariate discrete model. Finally, the procedure proposed in this paper
is illustrated through a classical change-point example
Dental caries status and its associated factors among 5-year-old Hong Kong children: A cross-sectional study
published_or_final_versio
Progenitor-like cells derived from mouse kidney protect against renal fibrosis in a remnant kidney model via decreased endothelial mesenchymal transition
Showing A quantification of GFP-positive cells in the lung after intravenous injection of MKPCs in five-sixths nephrectomized mice (y axis shows the number of cells, while the x axis (FL1-H) shows the fluorescence intensity; M1 is the area of GFP-positive cells) and B immunohistochemistry of the lung after intravenous injection of MKPCs into a mouse that underwent five-sixths nephrectomy. Few GFP positive cells were found in the lung at the first day but there were no GFP-positive cells at week 14. (TIFF 2253 kb
Occupational Skin Conditions in the Emerging US Green Collar Workforce.
-Financial support for this study provided by the National Institute for Occupational Safety and
Health (NIOSH) grant R03-OH010124
Crystal structure of Zen4 in the apo state reveals a missing conformation of kinesin
© 2017 The Author(s). Kinesins hydrolyse ATP to transport intracellular cargoes along microtubules. Kinesin neck linker (NL) functions as the central mechano-chemical coupling element by changing its conformation through the ATPase cycle. Here we report the crystal structure of kinesin-6 Zen4 in a nucleotide-free, apo state, with the NL initial segment (NIS) adopting a backward-docked conformation and the preceding α6 helix partially melted. Single-molecule fluorescence resonance energy transfer (smFRET) analyses indicate the NIS of kinesin-1 undergoes similar conformational changes under tension in the two-head bound (2HB) state, whereas it is largely disordered without tension. The backward-docked structure of NIS is essential for motility of the motor. Our findings reveal a key missing conformation of kinesins, which provides the structural basis of the stable 2HB state and offers a tension-based rationale for an optimal NL length to ensure processivity of the motor
A keystone microbial enzyme for nitrogen control of soil carbon storage
This is the final version. Available on open access from AAAS via the DOI in this recordData and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials and figshare (https://figshare.com/s/37aa98b76a7ef51da2e2). Correspondence should be addressed to Y.L. ([email protected]). Requests for additional materials and database should be addressed to J. Cao ([email protected]), R.-w.W. ([email protected]), and X.Z. ([email protected]).Agricultural and industrial activities have increased atmospheric nitrogen (N) deposition to ecosystems worldwide. N deposition can stimulate plant growth and soil carbon (C) input, enhancing soil C storage. Changes in microbial decomposition could also influence soil C storage, yet this influence has been difficult to discern, partly because of the variable effects of added N on the microbial enzymes involved. We show, using meta-analysis, that added N reduced the activity of lignin-modifying enzymes (LMEs), and that this N-induced enzyme suppression was associated with increases in soil C. In contrast, N-induced changes in cellulase activity were unrelated to changes in soil C. Moreover, the effects of added soil N on LME activity accounted for more of the variation in responses of soil C than a wide range of other environmental and experimental factors. Our results suggest that, through responses of a single enzyme system to added N, soil microorganisms drive long-term changes in soil C accumulation. Incorporating this microbial influence on ecosystem biogeochemistry into Earth system models could improve predictions of ecosystem C dynamics.Fundamental Research Funds for the Central Universitiesational Natural Science Foundation of China (NSFC)China Postdoctoral Science FoundationNatural Science Basic Research Plan in Shaanxi ProvinceState Key Laboratory of Loess and Quaternary GeologyKey Laboratory of Aerosol Chemistry and PhysicsInstitute of Earth Environment, Chinese Academy of SciencesUS Department of EnergyNSFNSFC-Yunnan United FundNational Science Fund for Distinguished Young ScholarsChina Scholarship Counci
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