Electrical‐current‐induced magnetization switching is a keystone concept in the development of spintronics devices. In the last few years, this field has experienced a significant boost with the ...discovery of spin orbit torque (SOT) in magnetic heterostructures. Here, the recent results as to the characterization and manipulation of SOT in various heavy‐metal/ferromagnet heterostructures are summarized. First, different electrical measurement methods that allow the physical features of SOT to be revealed are introduced. Second, it is shown that SOT in magnetic heterostructures can be manipulated via various material engineering approaches. The interfacial and bulk contributions of SOT are also discussed. These results advance the understanding of SOT and provide novel approaches toward energy‐efficient spintronic devices.
Spin orbit torque (SOT) is emerging as an efficient magnetic‐state control strategy for widespread modern memory and logic applications that are nonvolatile, scalable, and ultrafast. Recent developments on the characterization and manipulation of SOT in magnetic heterostructures are described, which lay the foundation for new‐generation spintronic devices.
The use of immunotherapies in the treatment of metastatic cancers has significantly advanced oncology. However, due to safety concerns, solid organ transplant recipients (SOTRs) are routinely ...excluded from immunotherapy trials; thus, there is limited data for these agents in this population.
A systematic review was performed to evaluate the safety and efficacy of immunotherapies in SOTRs with metastatic cancers. Fisher's exact test and Kruskal-Wallis test were used for analysis.
In total, 37% of patients experienced organ rejection, and 14% died as a result of graft rejection. Nivolumab was associated with the highest rejection rate (52.2%), followed by pembrolizumab (26.7%) and ipilimumab (25%; P = .1774). The highest rejection rate was seen in patients with kidney transplants (40.1%), then liver (35%) and heart (20%) transplants (P = .775), and 64% of patients succumbed to the progression of malignancy. For all cases, rates of progression or death secondary to disease were highest for ipilimumab (75%), followed by nivolumab (43%) and pembrolizumab (40%; P = .1892). The overall response rate was highest for pembrolizumab (40%), followed by nivolumab (30%) and ipilimumab (25%; P = .7929).
The small sample size.
Physicians must be cautious when administering immunotherapy to SOTRs. However, rejection is not the most common cause for death in this population.
Abstract
Current induced spin-orbit torques driven by the conventional spin Hall effect are widely used to manipulate the magnetization. This approach, however, is nondeterministic and inefficient ...for the switching of magnets with perpendicular magnetic anisotropy that are demanded by the high-density magnetic storage and memory devices. Here, we demonstrate that this limitation can be overcome by exploiting a magnetic spin Hall effect in noncollinear antiferromagnets, such as Mn
3
Sn. The magnetic group symmetry of Mn
3
Sn allows generation of the out-of-plane spin current carrying spin polarization collinear to its direction induced by an in-plane charge current. This spin current drives an out-of-plane anti-damping torque providing the deterministic switching of the perpendicular magnetization of an adjacent Ni/Co multilayer. Due to being odd with respect to time reversal symmetry, the observed magnetic spin Hall effect and the resulting spin-orbit torque can be reversed with reversal of the antiferromagnetic order. Contrary to the conventional spin-orbit torque devices, the demonstrated magnetization switching does not need an external magnetic field and requires much lower current density which is useful for low-power spintronics.
Quantitative investment theory has emerged as a prominent and widely researched domain within the financial markets, where investors predominantly focus on discerning the intricate influences of ...market dynamics. In this paper, we proposed a short-term prediction-based trading strategy, which can equiponderate between return and risk, considerations while accounting for investor risk preferences. This strategy employs GM(1,1) to capture nuanced features of price dynamics in short-term intervals and update the GM(1,1) model with the latest data. Subsequently, a multi-objective planning equation is formulated to optimize asset allocations by determining the optimal holding that strikes between specific returns and risk mitigation. In the end, this work conducts a case study and sensitivity analysis using five years of gold and bitcoin price data spanning from 2016 to 2021. This empirical examination serves to affirm the efficacy and resilience of the proposed trading strategy. The case study reveals that proficient short-term price forecasting serves as a potent means to proactively mitigate risk, facilitating, judicious and objective trading practices. Moreover, it underscores the strategy's tangible utility as a guide for real-world investment decisions.
Hydrothermal activity on mid‐ocean ridges plays an important role in shaping marine chemistry, yet the variability of hydrothermal venting and its forcing mechanism remain elusive. Here, we analyzed ...a sediment core obtained near the tectonic‐controlled Tianxiu vent field, Carlsberg Ridge, to reconstruct the hydrothermal venting history. The core documented two significant hydrothermal events (H1 and H2) in the past 30 ka. H1 occurred at 24.1–24.5 ka during the Last Glacial Maximum (LGM), while H2 occurred at 10.5–11.6 ka during the deglacial period. Compared to H2, H1 was relatively weak, and it occurred concurrently with a tectonic event. We suggest that H2 was caused by the increased melt production associated with the decompression melting of the upper mantle during sea‐level fall, which is consistent with previously published records, whereas H1 was likely triggered by an intense tectonic event associated with depressurization during the LGM, which was previously unrecognized.
Plain Language Summary
Hydrothermal systems are controlled not only by magmatism but also by tectonism. Previous studies have shown that there is a relationship between the variability of hydrothermal activity and sea‐level changes. Increased melt production during glacial periods has been invoked to explain the enhanced hydrothermal activities during glacial terminations. However, little attention has been paid to the relationship between hydrothermal activity and tectonic events during the glacial–interglacial cycle. Based on the analysis of a sediment core collected near the tectonic‐controlled Tianxiu vent field, Carlsberg Ridge, we reconstructed the hydrothermal venting history and found that enhanced hydrothermal activities not only occurred at 10.5–11.6 ka during the last glacial termination but also occurred concurrently with an intense tectonic event at 24.1–24.5 ka during the Last Glacial Maximum. We infer that this earlier hydrothermal event was induced by the improved permeability of the oceanic crust due to depressurization during the glacial sea‐level fall. This is the first time that the hydrothermal venting history of a tectonic‐controlled hydrothermal system in the Indian Ocean is characterized, and the coupling between hydrothermal and tectonic events associated with sea‐level changes is revealed.
Key Points
A 30 ka history of hydrothermal and tectonic activity was reconstructed for the Tianxiu vent field
The hydrothermal event at 24.1–24.5 ka was triggered by tectonic events resulting from depressurization during the Last Glacial Maximum
The hydrothermal event at 10.5–11.6 ka was caused by increased decompression melting of the upper mantle during the Last Glacial Maximum
Bottom currents play a major role in deep‐sea sedimentation, but their significance in the burial of organic carbon is poorly quantified at a global scale. Here we show that Holocene fluxes of ...organic carbon into the contourite drifts are high, with a global average of 0.09 g cm−2 Kyr−1. At individual drift sites, fluxes are commonly 1–2 orders of magnitude greater than rates in surrounding areas and in global depth‐similar zones. These high fluxes of organic carbon into the contourite drifts are due to high rates of sedimentation. Over the past 50 million years, sedimentation rates at the studied contourite drift sites have overall increased, coincident with decreasing atmospheric CO2 and a cooling global climate. Our work suggests that a ramp‐up of the bottom‐current carbon pump has accelerated removal of CO2 from the atmosphere and oceanic water, thus contributing to the overall global cooling after the Eocene Thermal Maximum.
Plain Language Summary
Bottom currents play a major role in deep‐sea sedimentation, but their significance in the burial of organic carbon is poorly quantified at a global scale. Here we examine data from modern contourite drifts (large‐scale, alongslope‐trending bottom‐current deposits) across the globe and show modern fluxes of organic carbon into the drifts are high, with a global average of 0.09 g cm−2 Kyr−1. At individual drift sites, fluxes are commonly 1 to 2 orders of magnitude greater than rates in surrounding areas and in global depth‐similar zones. These high fluxes of organic carbon into the drifts are due to high rates of sedimentation in these deepwater environments, which are driven primarily by vigorous bottom currents—in other words, by a bottom‐current pump that is highly efficient at burying organic carbon. Our work suggests that a ramp‐up of the bottom‐current carbon pump, attributable to progressive intensification of global ocean circulation over the past 50 million years, has accelerated removal of CO2 from the atmosphere and oceanic water, thus contributing to the global cooling after the Eocene Thermal Maximum. Sedimentary records of past organic carbon fluxes in contourite drifts over geologic time could well prove useful in informing predictions of future climate.
Key Points
Modern fluxes of organic carbon into the contourite drifts are high, with a global average of 0.09 g cm−2 Kyr−1
The fluxes into the drifts are commonly 1–2 orders of magnitude greater than rates in surrounding areas and in global depth‐similar zones
Over the past 50 million years, the bottom‐current pump has accelerated removal of carbon from the oceanic water
Analysis of vessel morphology is important in assessing intracranial atherosclerosis disease (ICAD). Recently, magnetic resonance (MR) vessel wall imaging (VWI) has been introduced to image ICAD and ...characterize morphology for atherosclerotic lesions. In order to automatically perform quantitative analysis on VWI data, MR angiography (MRA) acquired in the same imaging session is typically used to localize the vessel segments of interest. However, MRA may be unavailable caused by the lack or failure of the sequence in a VWI protocol. This study aims to investigate the feasibility to infer the vessel location directly from VWI. We propose to synergize an atlas-based method to preserve general vessel structure topology with a deep learning network in the motion field domain to correct the residual geometric error. Performance is quantified by examining the agreement between the extracted vessel structures from the pair-acquired and alignment-corrected angiogram, and the estimated output using a cross-validation scheme. Our proposed pipeline yields clinically feasible performance in localizing intracranial vessels, demonstrating the promise of performing vessel morphology analysis using VWI alone.
Autophagy of mitochondria, termed mitophagy, plays an important role in cerebral ischemia-reperfusion (IR) injury, but the mechanism is not yet clear. Tissue-type plasminogen activator (tPA) is the ...most important thrombolytic drug in the clinical treatment of ischemic stroke and has neuroprotective effects. Here, we explored the effects of tPA on neuronal apoptosis and mitophagy following IR. We found that knocking out the tPA gene significantly aggravated brain injury and increased neuronal apoptosis and mitochondrial damage. Exposure of neurons to tPA reduced injury severity and protected mitochondria. Further studies demonstrated that this protective effect of tPA was achieved via regulation of FUNDC1-mediated mitophagy. Furthermore, we found that tPA enhanced the expression level of FUNDC1 by activating the phosphorylation of AMPK. In summary, our results confirm that tPA exerts neuroprotective effects by increasing the phosphorylation of AMPK and the expression of FUNDC1, thereby inhibiting apoptosis and improving mitochondrial function.
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•After cerebral ischemia, tPA released by neurons has a neuroprotective effect.•tPA modulates mitophagy to decrease oxidative stress and inhibit apoptosis.•The mitochondrial membrane protein FUNDC1 and the AMPK signaling pathway are involved in the neuroprotective process of tPA.
Structurally controlled high-molecular-weight (HMW) polystyrenes (PSts) and block copolymers consisting of HMW PSt segments were successfully synthesized by emulsion organotellurium-mediated radical ...polymerization (TERP). The hydrophilicity of the organotellurium group of TERP chain transfer agents (CTAs) was important for success, and CTAs 1b and 1c with di- and tetraethylene glycol units were suitable. By using 1b and 1c and using hexadecyltrimethylammonium bromide (CTAB) as the surfactant, PSts with MWs over 1 million and with low dispersity (Đ < 1.6) were synthesized with >96% monomer conversion. Because of the high monomer conversion, high end-group fidelity, and rapid monomer diffusion to polymer particles, HMW block copolymers with low dispersity were successfully synthesized by adding a second monomer after converting the first monomer without isolating the macroinitiators. Despite recent developments in reversible-deactivation radical polymerization (RDRP), the synthesis of HMW polymers, particularly PSts and block copolymers, has been a formidable challenge. This method provides a valuable route for fabricating polymer materials based on HMW PSts.
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