seamount chain subduction zone interactions implications for accretionary and erosive subduction zone behavior

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Investigating the role of Hedgehog/GLI1 signaling in glioblastoma cell response to temozolomide.

Resistance to chemotherapy substantially hinders successful glioblastoma (GBM) treatment, contributing to an almost 100% mortality rate. Resistance to the frontline chemotherapy, temozolomide (TMZ), arises from numerous signaling pathways that are deregulated in GBM, including Hedgehog (Hh) signaling. Here, we investigate suppression of Hh signaling as an adjuvant to TMZ using U87-MG and T98G cell lines as in vitro models of GBM. We found that silencing GLI1 with siRNA reduces cell metabolic activity by up to 30% in combination with TMZ and reduces multidrug efflux activity by 2.5-fold. Additionally, pharmacological GLI inhibition modulates nuclear p53 levels and decreases MGMT expression in combination with TMZ. While we surprisingly found that silencing GLI1 does not induce apoptosis in the absence of TMZ co-treatment, we discovered silencing GLI1 without TMZ co-treatment induces senescence as evidenced by a significant 2.3-fold increase in senescence associated β-galactosidase staining, and this occurs in a loss of PTEN-dependent manner. Finally, we show that GLI inhibition increases apoptosis in glioma stem-like cells by up to 6.8-fold in combination with TMZ, and this reduces the size and number of neurospheres grown from glioma stem-like cells. In aggregate, our data warrant the continued investigation of Hh pathway inhibitors as adjuvants to TMZ chemotherapy and highlight the importance of identifying signaling pathways that determine whether co-treatment will be successful

Automatic Detection and Tracking of Coronal Mass Ejections. II. Multiscale Filtering of Coronagraph Images

Studying CMEs in coronagraph data can be challenging due to their diffuse structure and transient nature, and user-specific biases may be introduced through visual inspection of the images. The large amount of data available from the SOHO, STEREO, and future coronagraph missions, also makes manual cataloguing of CMEs tedious, and so a robust method of detection and analysis is required. This has led to the development of automated CME detection and cata- loguing packages such as CACTus, SEEDS and ARTEMIS. Here we present the development of a new CORIMP (coronal image processing) CME detection and tracking technique that overcomes many of the drawbacks of current catalogues. It works by first employing the dynamic CME separation technique outlined in a companion paper, and then characterising CME structure via a multiscale edge-detection algorithm. The detections are chained through time to determine the CME kinematics and morphological changes as it propagates across the plane-of-sky. The effectiveness of the method is demonstrated by its application to a selection of SOHO/LASCO and STEREO/SECCHI images, as well as to synthetic coronagraph images created from a model corona with a variety of CMEs. The algorithms described in this article are being applied to the whole LASCO and SECCHI datasets, and a catalogue of results will soon be available to the public.Comment: 18 pages, 10 figure

Mechanism of progressive broad deformation from oceanic transform valley to off-transform faulting and rifting

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Zhang, F., Lin, J., Zhou, Z., Yang, H., & Morgan, J. P. Mechanism of progressive broad deformation from oceanic transform valley to off-transform faulting and rifting. Innovation, 3(1), (2022): 100193, https://doi.org/10.1016/j.xinn.2021.100193.Oceanic transform faults (TFs) are commonly viewed as single, narrow strike-slip seismic faults that offset two mid-ocean ridge segments. However, broad zones of complex deformation are ubiquitous at TFs. Here, we propose a new conceptual model for the progressive deformation within broad zones at oceanic TFs through detailed morphological, seismic, and stress analyses. We argue that, under across-transform extension due to a change in plate motion, plate deformation occurs first along high-angle transtensional faults (TTFs) within the transform valleys. Off-transform normal faults (ONFs) form when across-transform deviatoric extensional stresses exceed the yield strength of the adjacent oceanic lithosphere. With further extension, these normal faults can develop into off-transform rift zones (ORZs), some of which can further develop into transform plate boundaries. We illustrate that such progressive complex deformation is an inherent feature of oceanic TFs. The new conceptual model provides a unifying theory to explain the observed broad deformation at global transform systems.We benefited from discussions with Drs. Tao Zhang, Huihui Weng, Yen Joe Tan, the SCSIO Deep Ocean Geodynamics Group, the CUHK Seismology Group, and the participants of the InterRidge transform fault workshop in France, 2018. This work was supported by the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) (GML2019ZD0205), NSFC grants (41976064, 41890813, 41976066, 91628301, and 91858207), CAS grants (Y4SL021001, QYZDY-SSW-DQC005, 133244KYSB20180029, 131551KYSB20200021, and ISEE2021PY03), National Key R&D Program of China grants (2018YFC0309800 and 2018YFC0310105), the Guangdong Basic and Applied Basic Research Foundation (2021A1515012227), and Hong Kong Research Grant Council grants (14304820 and 14306119)

Accelerator performance analysis of the Fermilab Muon Campus

Fermilab is dedicated to hosting world-class experiments in search of new physics that will operate in the coming years. The Muon g-2 Experiment is one such experiment that will determine with unprecedented precision the muon anomalous magnetic moment, which offers an important test of the Standard Model. We describe in this study the accelerator facility that will deliver a muon beam to this experiment. We first present the lattice design that allows for efficient capture, transport, and delivery of polarized muon beams. We then numerically examine its performance by simulating pion production in the target, muon collection by the downstream beam line optics, as well as transport of muon polarization. We finally establish the conditions required for the safe removal of unwanted secondary particles that minimizes contamination of the final beam.Comment: 10 p

Manipulation of magnetic solitons on odd-numbered macrospin rings

We report simulations of a frustrated odd-numbered macrospin ring system, with full point dipolar interactions, driven by a rotating uniform applied magnetic field of constant magnitude. The system is designed with equally-spaced radially-aligned macrospins, which must carry a frustrated soliton defect in its ground state. It is shown how correctly tuning the applied field magnitude can allow for non-trivial unidirectional propagation of the soliton, the required directional pressure acquired via the curvature of the ring. Furthermore, the system, which may be employed as a multiple rotation counter, is tested for robustness against quenched disorder as would be present in an experimental realization