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The development of responsive nanoplatforms based on the tumor microenvironment (TME) is critical for tumor diagnosis and treatment. Concentrating on a single TME‐responsive nanoplatform, however, may result in insufficient diagnostic accuracy and treatment efficacy. Herein, layered double‐hydroxides (LDHs) and rare earth nanomaterials (Er@Lu) were combined to create a triple TME‐responsive nanoplatform that was then modified with cypate (a fluorescent dye with strong absorbance) by a peptide chain and loaded with epigallocatechin gallate (EGCG), a chemotherapeutic drug. Multiple responses to TME occurred when Er@Lu/LDH‐EGCG reached the colorectal tumor region. Based on an acidic TME, the nanoplatform cracked and released Ni2+ and EGCG. NiS, which was produced by the reaction of Ni2+ with abundant H2S in tumor cells, was used for photothermal therapy and the released EGCG was used for chemotherapy. The MMP‐7 enzyme specifically expressed in tumor cells recognized and cut the peptide chain, resulting in cypate release. The fluorescence of the Er@Lu was then restored along with the release of cypate because of the absorption competition disappearance. Compared to a single TME response, Er@Lu/LDH‐EGCG with a triple TME response led to a better synergistic therapeutic effect in vitro and in vivo. This work has provided new approaches for developing multiple TME‐responsive therapeutic nanoplatforms for synergistic therapy with improved diagnosis and therapeutic efficiency. [ABSTRACT FROM AUTHOR]

Purpose: This work introduces and validates a deep‐learning‐based fitting method, which can rapidly provide accurate and robust estimation of cytological features of brain tumor based on the IMPULSED (imaging microstructural parameters using limited spectrally edited diffusion) model fitting with diffusion‐weighted MRI data. Methods: The U‐Net was applied to rapidly quantify extracellular diffusion coefficient (Dex), cell size (d), and intracellular volume fraction (vin) of brain tumor. At the training stage, the image‐based training data, synthesized by randomizing quantifiable microstructural parameters within specific ranges, was used to train U‐Net. At the test stage, the pre‐trained U‐Net was applied to estimate the microstructural parameters from simulated data and the in vivo data acquired on patients at 3T. The U‐Net was compared with conventional non‐linear least‐squares (NLLS) fitting in simulations in terms of estimation accuracy and precision. Results: Our results confirm that the proposed method yields better fidelity in simulations and is more robust to noise than the NLLS fitting. For in vivo data, the U‐Net yields obvious quality improvement in parameter maps, and the estimations of all parameters are in good agreement with the NLLS fitting. Moreover, our method is several orders of magnitude faster than the NLLS fitting (from about 5 min to <1 s). Conclusion: The image‐based training scheme proposed herein helps to improve the quality of the estimated parameters. Our deep‐learning‐based fitting method can estimate the cell microstructural parameters fast and accurately. [ABSTRACT FROM AUTHOR]

Distal C(sp2)−H and C(sp3)−H functionalizations have recently emerged as step‐economical tools for molecular synthesis. However, while the C(sp2)−C(sp3) construction is of fundamental importance, its formation through double remote C(sp2)−H/C(sp3)−H activation has proven elusive. By merging the ruthenium‐catalyzed meta‐C(sp2)−H functionalization with an aliphatic hydrogen atom transfer (HAT) process, we, herein, describe the catalyzed twofold remote C(sp2)−H/C(sp3)−H functionalizations via photo‐induced ruthenium‐mediated radical relay. Thus, meta‐C(sp2)−H arene bonds and remote C(sp3)−H alkane bonds were activated by a single catalyst in a single operation. This process was accomplished at room temperature by visible light—notably without exogenous photocatalysts. Experimental and computational theory studies uncovered a manifold comprising ortho‐C−H activation, single‐electron‐transfer (SET), 1,n‐HAT (n=5–7) and σ‐activation by means of a single ruthenium(II) catalyst. [ABSTRACT FROM AUTHOR]

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This paper investigates the secure lateral stabilization control problem of autonomous vehicles subject to actuator attacks. By considering a class of arbitrary bounded actuator attacks, a secure lateral control model of autonomous vehicles is established to characterize the influences of actuator attacks on steer actions. Based on the established attacked model, the event-based transmission scheme is used to save communication resources, and the sliding-model-like control scheme is developed to counteract the effects of actuator attacks. By exploiting the input delay approach, the periodic sampling and network-induced time delay are considered and thus the provided secure control scheme is beneficial to realize the secure control under networked environment. All theory results are well derived by Lyapunov–Kraskovskii method and some linear matrix inequality operations. In addition, Zeno behaviors are naturally excluded due to the adoption of discrete-time period sampling fashion. The effectiveness of the proposed secure control scheme is verified by a comparative simulation example. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Conflicting evidence exists regarding whether focal cerebral infarction contributes to cerebral amyloid‐β (Aβ) deposition, as observed in Alzheimer's disease. In this study, we aimed to evaluate the presence of Aβ deposits in the ipsilateral thalamus and hippocampus 12 months post‐stroke in non‐human primates, whose brains are structurally and functionally similar to that of humans. Four young male cynomolgus monkeys were subjected to unilateral permanent middle cerebral artery occlusion (MCAO), and another four sham‐operated monkeys served as controls. All monkeys underwent magnetic resonance imaging examination on post‐operative day 7 to assess the location and size of the infarction. The numbers of neurons, astrocytes, microglia and the Aβ load in the non‐affected thalamus and hippocampus ipsilaterally remote from infarct foci were examined immunohistochemically at sacrifice 12 months after operation. Thioflavin S and Congo Red stainings were used to identify amyloid deposits. Multiple Aβ antibodies recognizing both the N‐terminal and C‐terminal epitopes of Aβ peptides were used to avoid antibody cross‐reactivity. Aβ levels in cerebrospinal fluid (CSF) and plasma were examined using enzyme‐linked immunosorbent assay. The initial infarct was restricted to the left temporal, parietal, insular cortex and the subcortical white matter, while the thalamus and hippocampus remained intact. Of note, there were fewer neurons and more glia in the ipsilateral thalamus and hippocampus in the MCAO group at 12 months post‐stroke compared to the control group (all P < 0.05). However, there was no sign of extracellular Aβ plaques in the thalamus or hippocampus. No statistically significant difference was found in CSF or plasma levels of Aβ40, Aβ42 or the Aβ40/Aβ42 ratio between the two groups (P > 0.05). These results suggest that significant secondary neuronal loss and reactive gliosis occur in the non‐affected thalamus and hippocampus without Aβ deposits in the late period after MCAO in non‐human primates. [ABSTRACT FROM AUTHOR]

Seawater 87Sr/86Sr ratios have been used as a proxy for continental weathering flux and the partial pressure of atmospheric CO 2 (p CO 2) in Earth's past, but the fidelity of 87Sr/86Sr records in marine carbonates under diagenesis remains controversial. To investigate this issue, we undertook an integrated chemostratigraphic study of 87Sr/86Sr, δ13C, and δ18O in bulk carbonate from three cores of the South China Sea region: lithified bulk carbonate of Late Miocene to Holocene age in the 607-m-long Xike-1 core (0–11,942 kyr B.P.) from the Paracel (Chinese: Xisha) Islands, and unlithified carbonate sediment in two shallow (<5-m deep) pushcores from the Spratly (Chinese: Nansha) Islands, Jiuzhang A (0–680 yr B.P.) and Jiuzhang B (0–350 yr B.P.). The carbonate sediment of the Jiuzhang cores yielded 87Sr/86Sr signatures matching those of modern seawater, confirming that carbonate sediments can be faithful archives of contemporaneous oceanic Sr-isotopic compositions. Four diagenetic zones were identified in the Xike-1 core based on δ13C and δ18O patterns: meteoric (Unit I, 0–161 m), mixed-diagenetic (Unit II, 161–215 m), and marine diagenetic zones (Unit III, 215–577 m), along with a second meteoric zone (Unit IV, 577–607 m). The bulk‑carbonate 87Sr/86Sr profile was not strongly altered by dolomitization or other processes in any of the diagenetic zones (although minor effects were observed in the marine zone). This study concludes that marine carbonates are likely to retain primary seawater Sr isotopic signatures even after undergoing multiple stages of diagenesis. This study provides detailed 87Sr/86Sr secular variations and continental weathering history since 12 Ma. [ABSTRACT FROM AUTHOR]