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This paper aimed to investigate the antioxidant activity of buckwheat bee pollen polysaccharides (BWPP) during the in vitro gastrointestinal digestion. The crude polysaccharides were purified using DEAE-52 cellulose column and their antioxidant activity during in vitro simulated gastric and intestinal digestion was studied. The results showed that after purification by DEAE-52 cellulose column chromatography, the highest total sugar content component BWPP-1 was obtained, which was mainly composed of Glc, Xyl, Ara, etc. The infrared spectrum showed that BWPP-1 had obvious polysaccharide characteristic absorption peaks. During the simulated in vitro gastrointestinal digestion, the ABTS+· scavenging rates of BWPP and BWPP-1 reached their maximum values at 60 minutes of simulated gastric juice digestion, which were 86.39%±1.28% and 90.38%±2.78%, respectively. There was a significant difference compared to other digestion times (P<0.05). The DPPH· clearance rates reached their maximum values at 60 minutes, which were 86.86%±0.11% and 89.58%±1.67%, respectively, and the difference between the two was not significant (P>0.05). When simulating intestinal digestion, the maximum clearance rates of ABTS+· by BWPP and BWPP-1 reached 88.67%±0.40% and 91.82%±2.77% at 60 minutes, and the difference between the two was not significant (P>0.05). The DPPH· scavenging rates reached their peak values at 240 minutes of 57.11%±0.06% and 65.67%±3.67%, with significant difference (P<0.05). During the digestion process, the ability to reduce iron ions was relatively weak. Based on these findings, it can be concluded that BWPP and BWPP-1 have good ABTS+· and DPPH· scavenging abilities, and the DPPH· scavenging ability during gastric digestion is slightly higher than that during intestinal digestion, while the ABTS+· scavenging ability during intestinal digestion is slightly higher than that during gastric digestion. This study provides a theoretical basis for the development of functional products based on buckwheat bee pollen. [ABSTRACT FROM AUTHOR]

How to improve our episodic memory is an important issue in the field of memory. In the present study, we used a discriminative learning paradigm that was similar to a paradigm used in animal studies. In Experiment 1, a picture (e.g., a dog) was either paired with an identical picture, with a similar picture of the same concept (e.g., another dog), or with a picture of a different concept (e.g., a cat). Then, after intervals of 10 min, 1 d, and 1 wk, participants were asked to perform a 2-alternative forcedchoice (2AFC) task to discriminate between a repeated and a similar picture, followed by the contextual judgment. In Experiment 2, eye movements were measured when participants encoded the pairs of pictures. The results showed that by discriminative learning, there was better memory performance in the 2AFC task for the "same" and "similar" conditions than for the "different" condition. In addition, there was better contextual memory performance for the "similar" condition than for the other two conditions.With regard to the eye movements, the participants were more likely to fixate on the lure objects and mademore saccades between the target and lure objects in the "similar" (versus "different") condition. The number of saccades predicted how well the targets were remembered in both the 2AFC and contextual memory tasks. These results suggested that with discriminative learning of similar objects, detailed information could be better encoded by distinguishing the object from similar interferences, making the details and the contexts better remembered and retained over time.

A periodic mass-spring-truss chain based on a scissor-like structure and inertial amplification is proposed to seek for low-frequency vibration attenuation. The resonant and anti-resonant frequencies of a basic element are obtained analytically to explain the resonance and anti-resonance of the periodic chain. The formation of bandgaps is explored, revealing that the vertical movements of the vertices take the input kinetic energy away from the horizontal movement energy. The cut-off frequencies of three models are derived analytically to compare the effect of the inertia amplification, which can reach more than three times the classical mass-spring chain with a small angle. Also, the effect of stiffness amplification is presented when the spring mounted vertically, unlike the classical inertial amplification systems. Thus, the optimal configuration for low-frequency attenuation is obtained, that is, the spring mounted horizontally and the masses mounted at the upper and lower vertices. The chain with mass on the upper and lower vertices has the lowest cut-off frequency, which is 17.7% lower than that of the classical mass-spring chain. A diatomic chain is studied to find lower and wider bandgaps, where the central frequency is 25% lower than the classical mass-spring diatomic chain. The central frequency and width of the new bandgap can be tunable accordingly. The result shows that small angles or low stiffness ratios result in lower bandgaps. Meanwhile, the large angles, big differences of masses, or high stiffness ratios lead to wider bandgaps. [ABSTRACT FROM AUTHOR]

The high thermal budget of three-dimensional NAND Flash (3D NAND Flash) is the key issue limiting the increase in vertical integration. The main purpose of this article is to design a local and high temperature annealing function to reduce the thermal budget and gain a high activation rate without diffusion at a target depth to improve the performance of 3D NAND Flash devices by laser annealing with green wavelength. The method of nanosecond pulse laser annealing (ns-PLA) for amorphous silicon (a-Si) crystallization and activation has been proven, and this method has the benefits of a low thermal budget and controllable heating. According to previous experiments, one of the important results is that ns-PLA with high energy can provide a high temperature that reaches the melting point of a-Si and obtain a deep and monocrystal-like silicon channel through liquid phase crystallization in 3D NAND applications and obtain a higher activation rate. These results cast emerging light on low thermal budget processes based on ns-PLA in 3D NAND flash for future architecture such as Xtacking architecture, and have significant ramifications for impurity activation rates and reducing channel leakages. [ABSTRACT FROM AUTHOR]

The bit density is generally increased by stacking more layers in 3D NAND Flash. Lowering dopant activation of select transistors results from complex integrated processes. To improve channel dopant activation, the test structure of vertical channel transistors was used to investigate the influence of laser thermal annealing on dopant activation. The activation of channel doping by different thermal annealing methods was compared. The laser thermal annealing enhanced the channel activation rate by at least 23% more than limited temperature rapid thermal annealing. We then comprehensively explore the laser thermal annealing energy density on the influence of Poly-Si grain size and device performance. A clear correlation between grain size mean and grain size sigma, large grain size mean and sigma with large laser thermal annealing energy density. Large laser thermal annealing energy density leads to tightening threshold voltage and subthreshold swing distribution since Poly-Si grain size regrows for better grain size distribution with local grains optimization. As an enabler for next-generation technologies, laser thermal annealing will be highly applied in 3D NAND Flash for better device performance with stacking more layers, and opening new opportunities of novel 3D architectures in the semiconductor industry. [ABSTRACT FROM AUTHOR]

A novel vertical dual surrounding gate transistor with embedded oxide layer is proposed for capacitorless single transistor DRAM (1T DRAM). The embedded oxide layer is innovatively used to improve the retention time by reducing the recombination rate of stored holes and sensing electrons. Based on TCAD simulations, the new structure is predicted to not only have the characteristics of fast access, random read and integration of 4F2 cell, but also to realize good retention and deep scaling. At the same time, the new structure has the potential of scaling compared with the conventional capacitorless 1T DRAM. [ABSTRACT FROM AUTHOR]

Natural gas generation is the result of organic matter degradation under the effects of biodegradation and thermal degradation. Early Cambrian black shales in the Upper Yangtze Region are rich in organic matter and have shown great shale gas potentiality in recent years. Nevertheless, the enrichment mechanism and distribution of organic matter in these black shales between different sedimentary settings, such as intra-platform basin, slope, and deep basin, are still poorly understood. In this paper, based mainly on elemental geochemistry, a comprehensive study of the marine redox conditions, primary productivity, sedimentation rate, terrigenous input, hydrothermal activity, and water mass restrictions was conducted on the Early Cambrian Niutitang black shale in the Upper Yangtze Region. Our data showed that an intra-platform basin received a higher terrigenous input and that it deposited under more restricted conditions than the slope and deep basin settings. The primary productivity in the slope and deep basin settings was higher than that in the intra-platform basin setting. In the intra-platform basin, the productivity increased from its inner part to its margin. For the slope and deep basin settings, the high paleoproductivity generated large amounts of organic matter and its preservation was synergistically affected by the redox conditions. In contrast to the slope and deep basin, the preservation of organic matter in the inner part of the intra-platform basin was mainly controlled by redox conditions because the paleoproductivity in it was much lower than in the slope and deep basin settings. The intra-platform basin margin was the most favorable area for accumulating organic matter. [ABSTRACT FROM AUTHOR]

Reperfusion injury is still a major challenge that impedes neuronal survival in ischemic stroke. However, the current clinical treatments are remained on single pathological process, which are due to lack of comprehensive neuroprotective effects. Herein, a macrophage‐disguised honeycomb manganese dioxide (MnO2) nanosphere loaded with fingolimod (FTY) is developed to salvage the ischemic penumbra. In particular, the biomimetic nanoparticles can accumulate actively in the damaged brain via macrophage‐membrane protein‐mediated recognition with cell adhesion molecules that are overexpressed on the damaged vascular endothelium. MnO2 nanosphere can consume excess hydrogen peroxide (H2O2) and convert it into desiderated oxygen (O2), and can be decomposed in acidic lysosome for cargo release, so as to reduce oxidative stress and promote the transition of M1 microglia to M2 type, eventually reversing the proinflammatory microenvironment and reinforcing the survival of damaged neuron. This biomimetic nanomedicine raises new strategy for multitargeted combined treatment of ischemic stroke. [ABSTRACT FROM AUTHOR]

One important feature of episodic memory is that it contains fine-grained and vividly recollected details. How to improve and maintain detailed information over time has been one of the central issues in memory research. Previous studies have inconsistent findings on whether detailed memory is forgotten more rapidly than gist memory. In this study, we investigated to what extent different encoding tasks modulated forgetting of gist and detailed information. In three experiments, participants were presented pictures of common objects and were asked to name them (Experiment 1), describe the details about them (Experiment 2) or imagine scenes associated with them (Experiment 3). After intervals of 10 minutes, one day, one week and one month, gist and detailed memories of the pictures were tested and assessed using a remember/know/guess judgement. The results showed that after the naming task, gist and detailed memories were forgotten at a similar rate, but after the description and the imagination tasks, detailed memory was forgotten at a slower rate than gist memory. The forgetting rate of gist memory was the slowest after the naming task, while that of detailed memory was the slowest after the description task. In addition, when three experiments were compared, the naming task enhanced the contributions of recollection and familiarity for gist memory, while the description task enhanced the contribution of familiarity for detailed memory. These results reveal the importance of the encoding task in the forgetting of gist and detailed information, and suggest a possible way to maintain perceptual details of objects at longer intervals. [ABSTRACT FROM AUTHOR]

Lack of tumor‐infiltration lymphocytes (TILs) and resistances by overexpressed immunosuppressive cells (principally, myeloid‐derived suppressor cells (MDSCs)) in tumor milieu are two major challenges hindering the effectiveness of immunotherapy for "immune‐cold" tumors. In addition, the natural physical barrier existing in solid cancer also limits deeper delivery of drugs. Here, a tumor‐targeting and light‐responsive‐penetrable nanoplatform (Apt/PDGs^s@pMOF) is developed to elicit intratumoral infiltration of cytotoxic T cells (CTLs) and reeducate immunosuppressive microenvironment simultaneously. In particular, porphyrinic metal–organic framework (pMOF)–based photodynamic therapy (PDT) induces tumor immunogenic cell death (ICD) to promote CTLs intratumoral infiltration and hot "immune‐cold" tumor. Upon being triggered by PDT, the nearly 10 nm adsorbed drug‐loaded dendrimer de‐shields from the nanoplatform and spreads into the deeper tumor, eliminating MDSCs and reversing immunosuppression, eventually reinforcing immune response. Meanwhile, the designed nanoplatform also has a systemic MDSC inhibition effect and moderate improvement of overall antitumor immune responses, resulting in effective suppression of distal tumors within less significant immune‐related adverse effects (irAEs) induced. [ABSTRACT FROM AUTHOR]

3D NAND Flash with high storage capacity is in great demand for several technologies, which requires high performance and good reliability at the same time. Therefore, it is proposed to adjust the tunnel layer by changing the first SiO2 (O1) layer thickness near poly Si channel in the tunnel layer based on SiO2/SiOxNy/SiO2 structure. The optimal thickness of O1 layer is found. Under the optimal condition, program speed increased by 19% compared with no O1 layer deposition, though erase speed is slightly decreased by about 7%, the initial threshold voltage shift is improved greatly. Experimental results demonstrate that there are complex mechanisms affected by the dielectric constant, band barrier and equivalent oxide thickness. The optimization of O1 layer is useful towards an understanding of program/erase speed and retention characteristics. [ABSTRACT FROM AUTHOR]

Animals learn internal models that link specific behaviors to their anticipated sensory outcomes. In this issue of Neuron , Wallach and Sawtell 1 discover that freely moving fish learn how the sensory outcome of a single behavior changes with local context. Animals learn internal models that link specific behaviors to their anticipated sensory outcomes. In this issue of Neuron , Wallach and Sawtell discover that freely moving fish learn how the sensory outcome of a single behavior changes with local context. [ABSTRACT FROM AUTHOR]

The chromanone scaffold is a privileged structure in heterocyclic chemistry and drug discovery. A highly efficient copper-catalyzed asymmetric conjugated reduction of chromones is developed to give chiral chromanones with good yields (80–99%) and excellent ee values (94–＞99% ee). Particularly noteworthy is that chiral thiochromanones are also constructed using this method in 74–87% yields with 96–97% ee. The established asymmetric synthesis paves the way for their further pharmaceutical studies. [ABSTRACT FROM AUTHOR]

The suitable introduction of Fc-COOH with rich-electron features and fast electron transfer ability into Zr-MOFs obtains a trade-off between enhancing LMCT and frustrating Lewis acid for effective photocatalytic CO 2 RR. As pristine-MOF based photocatalysts, the superiority of the as-prepared material was experimentally and theoretically identified in detail. [Display omitted] • A series of Fc-modified NH 2 -UiO-66 MOFs are prepared for photocatalytic CO 2 RR. • An optimal Fc content endows MOF with satisfactory LMCT ability and Lewis acidity. • NH 2 -UiO-66-Fc (2.0) exhibits a CO yield of 90.65 μmol·g−1·h−1 with 100 % selectivity. • The photocatalytic performance is superior to most reported pristine MOF catalysts. • The superiority is attributed to a low rate-limiting step energy barrier of 1.50 eV. The introduction of rich-electron ligands is a promising strategy to improve the ligand-to-metal charge transfer (LMCT) ability of metal–organic frameworks (MOFs) for efficient photocatalytic CO 2 reduction reactions (CO 2 RR), while the resulting impaired Lewis acid sites go against stable bonding with CO 2 and hinder the electron transfering to CO 2. It is thus the key to search a trade-off between increasing LMCT and frustrating Lewis acid. Herein, the ferrocene (Fc) modified UiO-66 series MOFs, NH 2 -UiO-66-Fc, have been prepared to optimize LMCT for boosting CO 2 RR through a simple solvent-assisted ligand incorporation (SALI) method. Theoretical calculation and systematic experiments, including photoelectrochemical measures, in situ electron paramagnetic resonance, fluorescence probe analysis and X-ray photoelectron spectroscopy indicate that with increasing Fc content, the LMCT energy of MOFs significantly decreases from 2.66 to 2.10 eV based on the established electron transfer double-channel mechanism, while the Lewis acidity of Zr sites reduces with the CO 2 adsorption energy (E ad) ranging from −1.061 to −0.632 eV. Through introducing an optimal Fc content, NH 2 -UiO-66-Fc (2.0) integrating satisfactory LMCT ability and Lewis acidity shows superior photocatalytic CO 2 RR performance (CO yield: 90.65 μmol·g−1·h−1), about 13 times higher than that of the unmodified MOF and superior to most reported pristine MOF photocatalysts. DFT calculation demonstrates that the excellent performance of NH 2 -UiO-66-Fc (2.0) is attributed to the lowest energy barrier of 1.50 eV for the rate-limiting step of *COOH formation. In this work, such a simple post-modification strategy for facilitating the whole electron transfer path of photocatalytic CO 2 RR will provide a new way to construct high-performance MOFs-based CO 2 RR photocatalysts. [ABSTRACT FROM AUTHOR]

In article number 1806620, Chen Jiang and co‐workers, inspired by the ability of activated platelets to track tumor metastasis, develop a novel activated plateletstargeting micelle for efficient anticancer drug delivery to primary and metastatic tumors. After specifically binding to activated platelets in circulation, the micelles capture circulating tumor cells (CTCs) through the "platelet bridge" and eliminate CTCs to prevent metastasis. [ABSTRACT FROM AUTHOR]

The frequent relapse and metastasis characteristics of triple negative breast cancer (TNBC) make it a fraught issue with very poor prognosis in clinic. An effective treatment for TNBC should prevent and even eliminate metastasis as well as suppress primary lesion expansion. Recent progress reveals that platelets can be recruited and activated by tumor cells through intercellular adhesion molecules (ICAM), and help aggressive circulating tumor cells (CTCs) form metastasis. Therefore, activated platelets are considered with possession of tumor‐homing, CTC‐capturing, and metastasis‐targeting abilities. In this work, a P‐selectin (expressed on activated platelet surface) targeting peptide (PSN) is modified on a redox‐responsive paclitaxel‐loaded micelle (PSN‐PEG‐SS‐PTX4 micelle) to utilize activated platelets as a "bridge" for interaction with cancer cells. The PSN‐modified micelle can easily adhere to the surface of activated platelets and subsequently capture CTCs in blood circulation. Compared to Taxol and PEG‐SS‐PTX4 micelle, PSN‐PEG‐SS‐PTX4 micelle also exhibits enhanced primary TNBC/metastasis targeting and penetrating effect through binding with tumor infiltrating platelets and thus significantly improves treatment outcome. More importantly, PSN‐PEG‐SS‐PTX4 micelle potently suppressed lung metastasis of TNBC and reduced incidence of distant liver metastasis. The activated platelet‐targeting redox‐responsive micelle system provides a promising prospect for the omnidirectional treatment of metastatic cancer. A novel P‐selectin targeting micelle with controlled drug release is designed to utilize activated platelets as an endogenous device for efficient drug delivery to metastatic tumors. The micelle captures and eliminates circulating tumor cells via binding with activated platelets to prevent metastasis as well as penetrates and accumulates at primary tumors or metastasis via tumor‐infiltrating activated platelets. [ABSTRACT FROM AUTHOR]

Anticancer therapies, which can induce cell death and elevate antitumor immune response in the meantime, are considered as effective treatments for many types of cancers. Immunogenic cell death (ICD) induced by chemodrugs is a promising and typical strategy to achieve cell cytotoxicity and immunological enhancement together. However, due to the low level of ICD induction and less tumor‐targeting accumulation, application of traditional ICD inducers is limited. Here, tumor‐targeting core–shell magnetic nanoparticles (ETP‐PtFeNP:α‐enolase targeting peptide modified Pt‐prodrug loaded Fe3O4 nanoparticles) are developed to reinforce ICD induction of loaded‐oxaliplatin (IV) prodrug. After tumor‐targeting accumulation and endocytosis, platinum (IV) complexes are activated by intracellular reductive elimination to yield and release the Pt (II) congener, oxaliplatin, leading to DNA lesions and reactive oxygen species (ROS) generation. Simultaneously, in‐progress‐released ferric ions elicit highly toxic ROS (·OH or ·OOH) burst and interfere with the intracytoplasmic redox balance (like endoplasmic reticulum stress), leading to ICD‐associated immunogenicity enhancement and specific antitumor immune responses to kill the tumor cells synergistically. Meanwhile, the transverse relaxation rate R2 of ETP‐PtFeNP is remarkably increased by more than three times while triggered by reductant, suggesting ETP‐PtFeNP a high‐sensitivity T2 contrast agent for magnetic resonance imaging. A tumor‐targeting core–shell magnetic nanoparticle is designed to enhance the immunogenic cell death (ICD) induction of loaded‐oxaliplatin (IV) prodrug. Oxaliplatin‐based reactive oxygen species (ROS) generation and ferroptosis‐based ROS burst coherently reinforce the immunogenic characteristics of ICD, and lead to upregulation of antitumor immune response and downregulation of PD‐L2 mediated immunosuppression, eventually killing the tumor synergistically. [ABSTRACT FROM AUTHOR]

The cortex integrates sound- and movement-related signals to predict the acoustic consequences of behavior and detect violations from expectations. Although expectation- and prediction-related activity has been observed in the auditory cortex of humans, monkeys, and mice during vocal and non-vocal acoustic behaviors, the specific cortical circuitry required for forming memories, recalling expectations, and making predictions remains unknown. By combining closed-loop behavior, electrophysiological recordings, longitudinal pharmacology, and targeted optogenetic circuit activation, we identify a cortical locus for the emergence of expectation and error signals. Movement-related expectation signals and sound-related error signals emerge in parallel in the auditory cortex and are concentrated in largely distinct neurons, consistent with a compartmentalization of different prediction-related computations. On a trial-by-trial basis, expectation and error signals are correlated in auditory cortex, consistent with a local circuit implementation of an internal model. Silencing the auditory cortex during motor-sensory learning prevents the emergence of expectation signals and error signals, revealing the auditory cortex as a necessary node for learning to make predictions. Prediction-like signals can be experimentally induced in the auditory cortex, even in the absence of behavioral experience, by pairing optogenetic motor cortical activation with sound playback, indicating that cortical circuits are sufficient for movement-like predictive processing. Finally, motor-sensory experience realigns the manifold dimensions in which auditory cortical populations encode movement and sound, consistent with predictive processing. These findings show that prediction-related signals reshape auditory cortex dynamics during behavior and reveal a cortical locus for the emergence of expectation and error.

Metabolic interactions between different cell types in the tumor microenvironment (TME) often result in reprogramming of the metabolism to be totally different from their normal physiological processes in order to support tumor growth. Many studies have attempted to inhibit tumor growth and activate tumor immunity by regulating the metabolism of tumors and other cells in TME. However, metabolic inhibitors often suffer from the heterogeneity of tumors, since the favorable metabolic regulation of malignant cells and other cells in TME is often inconsistent with each other. Therefore, we reported the design of a pH-sensitive drug delivery system that targets different cells in TME successively. Outer membrane vesicles (OMVs) derived from Gram-negative bacteria were applied to coload paclitaxel (PTX) and regulated in development and DNA damage response 1 (Redd1)-siRNA and regulate tumor metabolism microenvironment and suppress tumor growth. Our siRNA@M-/PTX-CA-OMVs could first release PTX triggered by the tumor pH (pH 6.8). Then the rest of it would be taken in by M2 macrophages to increase their level of glycolysis. Great potential was observed in TAM repolarization, tumor suppression, tumor immune activation, and TME remolding in the triple-negative breast cancer model. The application of the OMV provided an insight for establishing a codelivery platform for chemical drugs and genetic medicines.

Efficient removal of deadly toxicants by blood purification remains predominant in poisoning treatment. Current strategies mainly rely on absorptive scavengers that normally have no selectivity to the adsorbates, which could result poor clinical outcomes to certain toxic species due to the passivity and inaccuracy of the detoxification procedure. Herein, a positive, accurate, and customized detoxification strategy was proposed. Based on the sophisticated molecule design and thoughtful structure analysis of the aimed toxicant paraquat, a supramolecular hunter stationed on red blood cells (RBC) is developed to continuously track paraquat in the blood. In this construct, a Janus dendrimer amphiphile (JDA) molecule was synthesized with the aim of facilely anchoring onto RBC membranes while bridging to load the antidote WP6 that could precisely recognize paraquat. In vitro and in vivo results demonstrate the effective toxicant-hunting and harm-neutralizing capability of the system through a guest-exchange reaction. This strategy provides a different insight in designing scavengers that can actively, precisely, and continuously hunt toxicants through a supramolecular approach.