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Let P\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal{P}$$\end{document} be a convex polygon in the plane, and let T\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal{T}$$\end{document} be a triangulation of P\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal{P}$$\end{document}. An edge e in T\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal{T}$$\end{document} is called a diagonal if it is shared by two triangles in T\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal{T}$$\end{document}. A flip of a diagonal e is the operation of removing e and adding the opposite diagonal of the resulting quadrilateral to obtain a new triangulation of P\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal{P}$$\end{document} from T\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal{T}$$\end{document}. The flip distance between two triangulations of P\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal{P}$$\end{document} is the minimum number of flips needed to transform one triangulation into the other. The Convex  Flip  Distance problem asks if the flip distance between two given triangulations of P\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal{P}$$\end{document} is at most k, for some given parameter k∈N\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$k \in \mathbb {N}$$\end{document}. It has been an important open problem to decide whether Convex  Flip  Distance is NP-hard. In this paper, we present an FPT\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\textsf {FPT}$$\end{document} algorithm for the Convex  Flip  Distance problem that runs in time O(3.82k)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\mathcal {O}(3.82^{k})$$\end{document} and uses polynomial space, where k is the number of flips. This algorithm significantly improves the previous best FPT\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\textsf {FPT}$$\end{document} algorithms for the problem. [ABSTRACT FROM AUTHOR]

The amygdala is essential for fear learning and expression. The central amygdala (CeA), once viewed as a passive relay between the amygdala complex and downstream fear effectors, has emerged as an active participant in fear conditioning. However, the mechanism by which CeA contributes to the learning and expression of fear is unclear. We found that fear conditioning in mice induced robust plasticity of excitatory synapses onto inhibitory neurons in the lateral subdivision of the CeA (CeL). This experience-dependent plasticity was cell specific, bidirectional and expressed presynaptically by inputs from the lateral amygdala. In particular, preventing synaptic potentiation onto somatostatin-positive neurons impaired fear memory formation. Furthermore, activation of these neurons was necessary for fear memory recall and was sufficient to drive fear responses. Our findings support a model in which fear conditioning-induced synaptic modifications in CeL favor the activation of somatostatin-positive neurons, which inhibit CeL output, thereby disinhibiting the medial subdivision of CeA and releasing fear expression. [ABSTRACT FROM AUTHOR]

Two new heterometallic complexes, [Bi(phen)I4Ag(phen)] n (1) and [Pb(bipy)Ag3I5] n (2) (phen = 1,10-phenanthroline, bipy = 2,2′-bipyridine), have been synthesized, significant for incorporation of heavy p-block metals (Pb and Bi) into iodoargentate frameworks to get heterometallic complexes. Complex 1 could be described as the combination of Ag(phen)I4 and Bi(phen)I4 octahedra by edge-sharing and 2 is constructed from and [Pb(2,2′-bipy)]2+ by Pb–I covalent bonds. Their optical band gaps, fluorescences, and thermal behaviors are also discussed. [ABSTRACT FROM AUTHOR]

Covalent organic polymers (COPs) memristors with multilevel memory behavior in harsh environments and photoelectric regulation are crucial for high‐density storage and high‐efficiency neuromorphic computing. Here, a donor–acceptor (D–A)‐type COP film (Py‐COP‐3), which is initiated by keto–enol tautomerism, is proposed for high‐performance memristors. Satisfactorily, the indium tin oxide (ITO)/Py‐COP‐3/Ag device demonstrates multilevel memory performance, even in high temperatures, acid‐base corrosion, and various organic solvents. Moreover, the performance can be modulated by the photoelectric effect to maintain a great switching behavior. By contrast, Py‐COP‐0, with similar structure and chemical composition to Py‐COP‐3 but without keto–enol tautomerism, exhibits binary storage performance. Further studies unravel that both the formation of conductive filaments and charge transfer within D‐A Py‐COP‐3 film contribute to the resistive switching behavior of memory devices. [ABSTRACT FROM AUTHOR]

The coming big‐data era has created a huge demand for next‐generation memory technologies with characters of higher data‐storage densities, faster access speeds, lower power consumption and better environmental compatibility. In this field, the design of resistive switching active materials is pivotal but challengeable. Polyoxometalates (POMs) are promising candidates for next‐generation molecular memristors due to their versatile redox characters, excellent electron reservoirs and good compatibility/convenience in microelectronics processing. In this review, five kinds of POM‐based active materials in nonvolatile memories (inorganic POMs, crystalline organic‐inorganic hybrid POMOFs, polymer modified POMs, POM/transition metal oxides composites and the deposition of POM on metal surfaces) were described. The components of POMs active materials, device fabrications, device parameters, and resistive switching mechanisms relative to their structures were summarized. Finally, challenges and future perspectives of POMs‐based memristors were also presented. [ABSTRACT FROM AUTHOR]

PVP encapsulation of 3D perovskite (TAZ-H)PbBr 3 can elevate its resistive switching level and ambient-air-stability simultaneously, which can be attributed to the presence of Pb-O coordinated bonds and inhibition of disordered-ordered transformation. [Display omitted] The study about simultaneously enhancing the resistive switching level and ambient-air-stability of perovskite-based memorizers will promote its commercialization. Here, a new 3D perovskite (TAZ-H)PbBr 3 (TAZ-H+ = protonated thiazole) has been fabricated as FTO/(TAZ-H)PbBr 3 /Ag device, which only exhibits binary memory performance with the high tolerant temperature of 170 °C. After encapsulating by polyvinylpyrrolidone (PVP), the (TAZ-H)PbBr 3 @PVP composite-based device can demonstrate ternary resistive switching behavior with considerable ON2/ON1/OFF ratio (105.9: 103.9:1) and high ternary yield (68 %). Specially, this device presents good ambient-air stability at RH 80 % and thermal tolerance of 100 °C. The binary resistive switching mechanism can be ascribed to the halogen ion migration induced by bromine defects in the (PbBr 3) n n– framework. But the ternary resistive switching phenomenon in the (TAZ-H)PbBr 3 @PVP-based device could be depicted as the carrier transport from filled traps of PVP to (PbBr 3) n n– framework (ON1 state) and then carriers flowing in the re-arranged (TAZ-H) n n+ chain in 3D channels (ON2 state). The PVP treatment can not only modify the grain boundary defects, but also facilitate the transport of injected carriers to the perovskite films via Pb-O coordinated bonds and inhibition of order-disorder transformation. This facial strategy for implementing ternary perovskite-based memorizers with good ambient-air-stability is quite meaningful for high-density memory in harsh environments. [ABSTRACT FROM AUTHOR]

Two new metal-organic frameworks of [Zn(bdc)(dfp)]·2DMF ( 1) and [Zn(bdc-NH)(dfp)]·DMF ( 2) (Hbdc = 1,4-benzenedicarboxylic acid, Hbdc-NH = 2-amino-1,4-benzenedicarboxylic acid and Hdfp = deferiprone) have been used as matrices for the drug carrier of 5-fluorouracil (5-FU). Drug loading content and drug release behavior of 1-2 were studied. These results indicate that their adsorption capacities for 5-FU were 38.4 and 35.9 wt% for 1 and 2, respectively. The drug release behaviors of 1-2 at different pH values (40, 6.0 and 7.4) and different temperature (37 and 40 °C) were investigated. A structure-activity relationship strategy has been conducted with the aim of rationalizing the experimental drug uptakes and emphasizing the relevant chemical and structural features that significantly impact their encapsulation and releasing performances in 1-2. Graphical Abstract: A structure-activity relationship strategy has been conducted with the aim of rationalizing the experimental drug uptakes and emphasizing the relevant chemical and structural features that significantly impact their encapsulation and releasing performances in 1-2. [ABSTRACT FROM AUTHOR]

Zero dimensional antimony(III) halides have captured more and more attention as broadband emitters. Herein, Using photochemically active ruthenium complexes as templates, two new antimony(III) halide based hybrids have been prepared and structurally determined, i.e., [Ru(bipy)3](Sb2Cl6O) (1) and [Ru(phen)3](SbI5) (2). Both the (Sb2Cl6O)2- and (SbI5)2-are rare examples of antimony halides, in which Sb centers are in square pyramidal environments with stereochemically active lone pairs. The (Sb2Cl6O)2- ion bearing secondary Sb···Cl interactions are further stabilized by C-H···Cl hydrogen bonds to give a quasi-3D network. The (SbI5)2- anions are anchored in the 1D[Ru(phen)3]n2n+ chains based on strong π···π stacking interactions among phenanthroline ligands, which are the reason for the formation of its square pyramid geometry.1 exhibits bright red luminescence but 2produces weak blue emission. This trend might be assigned to the larger conjugated system of phenanthroline in 2, which is dominant by ruling out the contribution of antimony(III) halide. Besides, reversible thermochromism can be found in 1. Furthermore, good electrical chemical and photocurrent performance can be detected. The photoluminescence modulation by controlling the conjugated degree of organic ligands is an efficient strategy for the precise preparation of new luminescent materials. Two antimony(III) halide-based hybrids template byruthenium complexes have been prepared, whose rare (Sb2Cl6O)2- and (SbI5)2- anions are stereo chemically active. Different luminescent performances (bright red and weak blue) might be assigned to the larger conjugated system of phenanthroline. Besides, reversible thermochromism and good photocurrent performance can be found. [ABSTRACT FROM AUTHOR]

High-fat diet (HFD)-induced obesity is a growing epidemic and major health concern. While excessive daytime sleepiness (EDS) is a common symptom of HFD-induced obesity, preliminary findings suggest that reduced wakefulness could be improved with time-restricted feeding (TRF). At present, however, the underlying neural mechanisms remain largely unknown. The paraventricular thalamic nucleus (PVT) plays a role in maintaining wakefulness. We found that chronic HFD impaired the activity of PVT neurons. Notably, inactivation of the PVT was sufficient to reduce and fragment wakefulness during the active phase in lean mice, similar to the sleep–wake alterations observed in obese mice with HFD-induced obesity. On the other hand, enhancing PVT neuronal activity consolidated wakefulness in mice with HFD-induced obesity. We observed that the fragmented wakefulness could be eliminated and reversed by TRF. Furthermore, TRF prevented the HFD-induced disruptions on synaptic transmission in the PVT, in a feeding duration-dependent manner. Collectively, our findings demonstrate that ad libitum access to a HFD results in inactivation of the PVT, which is critical to impaired nocturnal wakefulness and increased sleep, while TRF can prevent and reverse diet-induced PVT dysfunction and excessive sleepiness. We establish a link between TRF and neural activity, through which TRF can potentially serve as a lifestyle intervention against diet/obesity-related EDS. [ABSTRACT FROM AUTHOR]

This article describes the new economic decarboxylative trifluoromethylating reagent [Cu(phen)(O2CCF3)] ( 1; phen=1,10-phenanthroline) and the efficient difluorocarbene precursor [Cu(phen)2][O2CCF2Cl] ( 2). Treatment of copper tert-butoxide with phen and subsequent addition of trifluoroacetic acid or chlorodifluoroacetic acid afforded air-stable complexes 1 and 2, respectively, which were characterized by X-ray crystallography. The copper(I) ion in 1 is coordinated by a bidentate phen ligand, a monodentate trifluoroacetate group, and a molecule of CH3CN in a distorted tetrahedral coordination geometry. The molecular structure of 2 adopts an ionic form that consists of a [Cu(phen)2]+ cation and a chlorodifluoroacetate anion. Complex 1 reacted with a variety of aryl and heteroaryl halides to form trifluoromethyl (hetero)arenes in good yields. The corresponding Hammett plot exhibited a linear relationship and a reaction parameter ( ρ)=+0.56±0.02, which indicated that the trifluoromethylation reaction proceeded via a nucleophilic reactive species. Complex 2 reacts with phenols to produce aryl difluoromethyl ethers in modest-to-excellent yields. Mechanistic investigations revealed that the difluoromethylation reaction proceeds by initial copper-mediated formation of difluorocarbene and subsequent concerted addition of difluorocarbene to the phenol to form a three-center transition state. [ABSTRACT FROM AUTHOR]

An efficient and practical approach to α-trifluoromethylthio-substituted ketones was developed. The trifluoromethylthiolation of (bpy)Cu(SCF3) (bpy = 2,2′-bipyridyl) with various α-bromo ketones afforded the desired α-trifluoromethylthio-substituted ketones in good yields. The reaction tolerates more functionally than previously reported methods and demonstrates efficient scalability and practicality. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) batteries are thought to be the most likely to replace traditional intercalation-based lithium-ion batteries for energy storage devices because of its high theoretical mass energy density. However, the poor cycling stability resulting from dissolution of polysulfide intermediates (Li 2 S x , 3≤ x ≤8) greatly hampers the commercial applications. Herein, a 3D hierarchical mesoporous carbon with P/N dual-doped (3D-PNMC) as a catalytic host for sulfur electrode is successfully prepared. The as-prepared Li-S batteries with S@3D-PNMC cathode deliver a specific capacity of 1326 mAh g−1 at 0.1 C and the corresponding area capacity of up to 5.57 mAh cm−2. And also, the calculative capacity decay rate of S@3D-PNMC cathode is only 0.05% per cycle, which significantly lower than that of S@C electrode (0.21%). The satisfactory electrochemical performance can be ascribed to the 3D host not only provides space for the active sulfur loading, but also accelerates the electron transfer inside the electrode. Especially, electroactive sites created by phosphorus and nitrogen doping can effectively improve the electrochemical reaction kinetics to achieving long cycling stability. [Display omitted] • P/N dual-doped porous carbon with three-dimensional structure as host was prepared for Li-S batteries. • Strong catalysis between polysulfides result in the rapid conversion from sulfur to Li 2 S. • The S@3D-PNMC establish a polysulfides redox conversion pathway through "Capture-Diffusion-Precipitation" process. • Cathodes with a relatively high sulfur mass loading (4.2 mg cm−2) were fabricated. • Thus-derived S@3D-PNMC cathode showed outstanding cycling stability and rate performance. [ABSTRACT FROM AUTHOR]

Abstract: β-arrestin 2 plays important physiological roles in regulating the function of the μ opioid receptor (μOR) in vivo. Periaqueductal gray (PAG) is a potential structure where morphine produces its antinociception, but it is unclear whether β-arrestin 2 plays its regulatory effect on morphine at PAG. In the present study β-arrestin 2 overexpression was induced by adenovirus at PAG of rats. Morphine was administrated in these rats through PAG microinjection and systemic administration. The antinociceptive effects of morphine were abolished in rats received microinjection of morphine at PAG and partially attenuated in rats received systemic administration of morphine. These findings support the notion that PAG is an important site where β-arrestin 2 plays its regulatory effects on morphine analgesia. [Copyright &y& Elsevier]

The low efficiency of growing single-walled carbon nanotubes (SWCNT) poses a barrier to their application in high-performance electronic devices. However, it is difficult to control the uniform growth of SWCNT in a floating catalytic reactor due to the complex parameter control. Therefore, it is essential to enhance the growth of SWCNT in the floating catalyst chemical vapor deposition (FCCVD) process. In the present work, the influence of the reactive flow field on the growth of SWCNT, which is often neglected, is revealed. To address this issue, this work combines experiments and simulations to obtain the characteristics of the field distribution within the reactor and the trend of the products. The results of the flow field analysis indicate that thermal buoyancy is the cause of SWCNT growth limitation in FCCVD. By weakening the thermal buoyancy, a homogeneous reaction field is obtained; vortices in the flow field are reduced or even disappear; the temperature field is more homogeneous, and, importantly, the crystallinity of SWCNT is enhanced (I G /I D up to 20-fold). In addition, the decomposition process of the carbon source is also enhanced, thus suppressing the generation of by-products. Based on the results of the small tube experiments, both the increase in temperature and the decrease in residence time increased the I G /I D. Furthermore, the distributions of the maximum and minimum diameters in SWCNT imply variations in the growth modes of SWCNT at different temperatures. [Display omitted] • CFD was used to simulate the flow distribution inside the reactor. • The quality of SWCNT was improved using a simple method in the FCCVD process. • The time-dependent and temperature-dependent growth of SWCNT was investigated. [ABSTRACT FROM AUTHOR]

[Display omitted] • BPO 4 with in-situ Brønsted acid sites was employed for glycerol dehydration. • BPO 4 shows high acrolein yield of 80 % and robust stability during 425 h test. • In-situ Brønsted acid site is highly selective for the secondary hydroxyl groups. • The construction of B[3] and P[4] defects is a prerequisite for the active site. Dehydroxylation of biomass-based platform molecules is critical for obtaining building blocks for use in the chemical industry. Acid catalytic dehydration has provided a feasible route. However, simultaneously pursuing high product-selective and ultra-stable catalysts for the dehydroxylation of polyols remains an open challenge. In this study, a strategy for in-situ Brønsted acid sites (BAS) with chemo-adsorption selectivity is proposed. The construction of defect sites B[3] and P[4] species has been proved to be a prerequisite for the dynamic acid site formation at hydrothermal conditions. The BPO 4 catalyst with in-situ BAS can achieve the high selectivity of acrolein (∼80%) and robust stability of catalyst (over 425 h) using glycerol dehydration as a model reaction. In addition, in-situ BAS is highly selective for secondary hydroxyl groups and has been extended to other substrate applications. This catalytic strategy provides a green, efficient, and economical approach for converting biomass-derived polyols to high-value-added chemicals. [ABSTRACT FROM AUTHOR]

The bed nucleus of the stria terminalis (BNST) plays a critical role in regulating anxiety, yet the involved specific cell types and their connections functioning in anxiety-related behaviors remains elusive. Here we identified two cell subpopulations—corticotropin-releasing hormone-positive (CRH+) and protein kinase C- δ -positive (PKC- δ +) neurons—each displayed discrete emotionally valenced behaviors in the anterior-dorsal BNST (adBNST). Using whole-cell patch-clamp recordings and virus-assisted circuit tracing techniques, we delineated the local and long-range connectivity networks in a cell-type-specific manner. The results show that the CRH+ and PKC- δ + neurons received inputs from similar brain regions and exhibited significant differences in the downstream projection density. In addition, in vivo calcium imaging as well as gain- and loss-of-function studies characterized the physiological response properties and the functional heterogeneities in modulating anxiety, further suggesting the similarity and individuality between the two adBNST cell types. These results provide novel insights into the circuit architecture of adBNST neurons underlying the functionally specific neural pathways that relate to anxiety disorders. [ABSTRACT FROM AUTHOR]

Secretory carrier membrane proteins (SCAMPs) play an important role in exocytosis in animals, but the precise function of SCAMPs in human disease is unknown. In this study, we identified a homozygous mutation, SCAMP5 R91W, in a Chinese consanguineous family with pediatric epilepsy and juvenile Parkinson's disease. Scamp5 R91W mutant knock-in mice showed typical early-onset epilepsy similar to that in humans. Single-neuron electrophysiological recordings showed that the R91W mutation significantly increased the frequency of miniature excitatory postsynaptic currents (mEPSCs) at a resting state and also increased the amplitude of evoked EPSCs. The R91W mutation affected the interaction between SCAMP5 and synaptotagmin 1 and may affect the function of the SNARE complex, the machinery required for vesicular trafficking and neurotransmitter release. Our work shows that dysfunction of SCAMP5 shifted the excitation/inhibition balance of the neuronal network in the brain, and the deficiency of SCAMP5 leads to pediatric epilepsy. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-CN) nanosheets (CNNs) with an ultra-high quantum yield (80.1%) ultraviolet fluorescence (FL) were prepared. The effects of the lateral size and the polymerization temperature on the optical properties of CNNs have been studied. The ultraviolet FL was proved to have originated from the isolated melem units according to the density functional theory calculation and mass spectra. The obtained CNNs are further used as a pH probe due to the dependence of the FL signal on the pH of the solution. [ABSTRACT FROM AUTHOR]

Unbaffled U-shaped mesoscale oscillatory flow reactors (meso-OFRs) were developed to prevent solid deposition and prepare uniform barium sulfate (BaSO 4) nanoparticles with environmental protection function. The results showed that the oscillation significantly reduced granular deposition; the greater the intensity of the oscillation, the faster it reached uniformity, and the less likely the granules were to be deposited. These results can be explained by the formation of a larger vortex size, which can strengthen the turbulent mixing of fluid in the reactor, promote the interaction and forced mixing between the liquid phase and solid particles, enhance the internal shear stress of the fluid, and contribute to the secondary suspension of solid particles and the disintegration of particle agglomeration. The prepared BaSO 4 nanoparticles with oscillation were smaller in size and lower in pressure drop than those produced without oscillation, which conclusively illustrated that oscillation effectively prevented channel deposition and clogging. [Display omitted] • The meso-OFR could prevent solid deposition and prepare uniform nanoparticles. • The formation of vortex contributed to the secondary suspension of solid particles. • The prepared BaSO 4 nanoparticles were smaller in size and lower in pressure drop. [ABSTRACT FROM AUTHOR]

Relief, the appetitive state after the termination of aversive stimuli, is evolutionarily conserved. Understanding the behavioral role of this well-conserved phenomenon and its underlying neurobiological mechanisms are open and important questions. Here, we discover that the magnitude of relief from physical stress strongly correlates with individual resilience to depression-like behaviors in chronic stressed mice. Notably, blocking stress relief causes vulnerability to depression-like behaviors, whereas natural rewards supplied shortly after stress promotes resilience. Stress relief is mediated by reward-related mesolimbic dopamine neurons, which show minute-long, persistent activation after stress termination. Circuitry-wise, activation or inhibition of circuits downstream of the ventral tegmental area during the transient relief period bi-directionally regulates depression resilience. These results reveal an evolutionary function of stress relief in depression resilience and identify the neural substrate mediating this effect. Importantly, our data suggest a behavioral strategy of augmenting positive valence of stress relief with natural rewards to prevent depression. [Display omitted] • Magnitude of stress relief positively correlates with resilience to depression • Stress relief persistently activates VTA-DA neurons • DA projections to NAcLat and dNAcMed encode relief to prevent despair and anhedonia • Providing natural rewards at stress termination increases resilience to depression Dong et al. identify stress relief as a natural resilience mechanism against depression-like behaviors, delineate underlying dissociable mesoaccumbal dopamine circuits for preventing despair or anhedonia, and introduce a non-invasive behavioral strategy for promoting resilience. [ABSTRACT FROM AUTHOR]

Wavefront shaping (WFS) techniques have been used as a powerful tool to control light propagation in complex media, including multimode fibers. In this paper, we propose a new application of WFS for multimode fiber-based sensors. The use of a single multimode fiber alone, without any special fabrication, as a sensor based on the light intensity variations is not an easy task. The twist effect on multimode fiber is used as an example herein. Experimental results show that light intensity through the multimode fiber shows no direct relationship with the twist angle, but the correlation coefficient (CC) of speckle patterns does. Moreover, if WFS is applied to transform the spatially seemingly random light pattern at the exit of the multimode fiber into an optical focus. The focal pattern correlation and intensity both can serve to gauge the twist angle, with doubled measurement range and allowance of using a fast point detector to provide the feedback. With further development, WFS may find potentials to facilitate the development of multimode fiber-based sensors in a variety of scenarios. [ABSTRACT FROM AUTHOR]

This article, titled "Cover Feature: The Old Polyoxometalates in New Application as Molecular Resistive Switching Memristors," explores the use of polyoxometalates (POMs) in molecular resistive switching memristors. The article discusses five different types of POM-based active materials and their potential as next-generation molecular memristors. It provides information on the components of these materials, device fabrication, device parameters, and resistive switching mechanisms. The article is authored by Hailong Yang, Guoli Yue, Tao Li, Lingling Du, Haohong Li, Zhirong Chen, and Shoutian Zheng. [Extracted from the article]

LiFSI (lithium bis(fluorosulfonyl)imide) is a promising lithium salt for electrolytes in Li-ion batteries. However, the accumulation of harmful gases and heat during LiFSI hydrolysis could lead to serious safety accidents. Here we systematically investigate LiFSI hydrolysis processes under comprehensive conditions: higher temperature/acidity/basicity and lower water content can accelerate the hydrolysis, whereas the presence of DEC (diethyl carbonate) solvent, and other alkali metals (Na+, K+) can stabilize FSI−. Unexpectedly, under alkaline conditions, temperature/water content could not affect the hydrolysis greatly. By monitoring the hydrolysis intermediates and products using time-dependent ion chromatography, infrared spectra, and nuclear magnetic resonance, the hydrolysis routes are proposed and validated by accelerating rate calorimetry, differential scanning calorimetry measurements, and theoretical calculations. Under neutral/acidic conditions, electrophilic attack on the S–N bond generates FSO 2 NH 2 and FSO 3 −, while nucleophilic attack on the S–F bond produces FSO 2 NSO 3 2− and SO 3 NHSO 3 2− under alkaline conditions. As indicated by DFT calculation, the weaker S–N bond and larger S–N–S angle facilitate the electrophilic attack under acid conditions. Furthermore, very unstable intermediates (FSO 2 NH 2 and CH 3 CH 2 OSO 3 H) are determined for the first time. Based on these hydrolysis mechanisms, strategies for inhibiting LiFSI hydrolysis are provided, which is significant for the high-efficiency production and safe storage/transportation of LiFSI. [Display omitted] • LiFSI hydrolysis in comprehensive conditions has been investigated. • Hydrolysis routes are proposed by monitoring intermediates and products. • Two very unstable intermediates in LiFSI hydrolysis have been firstly determined. • The weaker S–N bond and larger S–N–S angle facilitate electrophilic attack. [ABSTRACT FROM AUTHOR]

Cu/Ag(I) were introduced into iodoplumbate systems to produce two new heterometallic iodoplumbates with viologen as templates, i.e. (PV)2(Pb2Cu2I10) (1) and [(BV)(Pb2AgI7)]n(2) (PV2+ = propyl viologen, BV2+ = benzyl viologen), in which the common connection of PbI6units have been remarkably altered. In (PV)2(Pb2Cu2I10) (1), two PbI6octahedra are bridged by two CuI4tetrahedra via face-sharing to give a (Pb2Cu2I10)4−cluster, but the ternary one-dimensional polymeric (Pb2AgI7)n2n−of [(BV)(Pb2AgI7)]n(2) is assembled from edge-sharing AgI4tetrahedra and PbI6octahedra. Their optical band gaps and fluorescence were also discussed. The absorption edges of haloplumbates could be engineered by introduction of suitable conjugated molecules as templates. [ABSTRACT FROM AUTHOR]

[Display omitted] • New Ln-MOFs can serve as multifunctional platforms. • Low cost CH 3 NH 3 PbBr 3 @Ln-MOFs show tunable luminescence behaviour. • CH 3 NH 3 PbBr 3 @Sm-MOF exhibits excellent electrical bistability behaviour with high ON/OFF ratio of 104. • CH 3 NH 3 PbBr 3 @Ln-MOFs can be utilized as a new generation of photovoltaic, light-emitting and switching memory devices. Metal organic frameworks (MOFs) contain ordered pores capable of encapsulating varied types of guests and provide a platform to expand the flexibility and versatility of the host-guest composites. Herein, by encapsulating CH 3 NH 3 PbBr 3 NP S into Ln-MOFs (Ln = La, Nd, Pr, Sm), four CH 3 NH 3 PbBr 3 @Ln-MOFs host-guest composites were fabricated and served as a bifunctional platform. The temperature-dependent luminescence properties of the CH 3 NH 3 PbBr 3 @Ln-MOFs were explored and the results revealed their tuneable green luminescence performance. In particular, the CH 3 NH 3 PbBr 3 @Sm-MOF exhibits a variety of colours from green to blue to purple and an excellent quantum yield of 0.98. The photocurrent responses and theoretical calculations reveal the enhancement mechanism of CH 3 NH 3 PbBr 3 on charge-hole separation owing to its unique host-guest synergy. Moreover, the CH 3 NH 3 PbBr 3 @Sm-MOF exhibits the excellent electrical bi-stability with a high ON/OFF ratio of 104. Hence, the CH 3 NH 3 PbBr 3 @Ln-MOFs host-guest composites are promising candidates for a new generation of photovoltaic, light-emitting, and switching memories devices. [ABSTRACT FROM AUTHOR]

The robust graphite-like melamine-cyanuric acid hydrogen-bonded organic framework was firstly fabricated as a new type of ternary memorizer with a high ternary yield and good environmental tolerances, whose mechanism is the filled traps in 2D layer (ON1) and the carriers flowing in 3D network (ON2) upon external voltage. This HOF-based ternary memorizer can pave a new way for efficient and facial implementation of multi-level memory. [Display omitted] • Melamine (M)-cyanuric acid (C) hydrogen-bonded organic framework (M−C HOF) was firstly fabricated as a new type of ternary memorizer. • The FTO/ M−C /Ag device exhibits considerable OFF/ON1/ON2 current ratio of 1:103.1:104.6, relatively low set voltages (1.14 and 1.70 V) and high ternary device yield of 74 %. • The ternary memorizer is ascribed to the filled traps in 2D layer (for ON1 state) and the carriers flowing in 3D network (for ON2 state). • This ternary memorizer has superior thermal stability (300 °C) and irradiative tolerance. The low ternary yield and expensive organic active materials hinder the potential industrialization of organic multi-level resistive memories. Here, facile melamine (M)-cyanuric acid (C) hydrogen-bonded organic framework (M−C HOF) was firstly fabricated as a new type of ternary memorizer. In the M−C HOF, the robust graphite-like planar 2D sheet along ab -plane containing a rosette motif is constructed from nine hydrogen bonds among M and C , and the 2D sheets are stacked into a 3D network through strong π – π stacking interactions. The FTO/ M−C /Ag device exhibits a typical ternary memory performance with considerable OFF/ON1/ON2 current ratio of 1:103.1:104.6, relatively low set voltages (1.14 and 1.70 V), good reliability, and high ternary device yield of 74 %. The ternary resistive switching behavior could be ascribed to the filled traps in 2D layer (for ON1 state) and the carriers flowing in 3D network (for ON2 state), which have been verified by quenched fluorescence of isolated M and C , increased (2 0 1) lattice plane distance upon external voltages. Besides, this ternary memorizer has superior thermal stability (300 °C) and irradiative tolerance. This attempt of HOF-based ternary memorizer presents a new choice for efficient and facial multi-level resistive material. [ABSTRACT FROM AUTHOR]

Novel fluoroalkylation reagents for preparation of trifluoromethylated (hetero)arenes and aryldifluoromethyl ethers are introduced. [ABSTRACT FROM AUTHOR]

A reaction of acetonitrile-solvated AgOCF3 with 1 equiv. of Aryl-BIAN ligand in THF at room-temperature afforded the silver(i) complex (Aryl-BIAN)AgOCF3 (1) in 75% yield. The crystal structure of this silver(i) trifluoromethoxide was determined by single-crystal X-ray crystallography. The molecular structure of 1 shows the metal centre bound to one molecule of BIAN, one trifluoromethoxide and one THF solvate, resulting in a distorted tetrahedral silver. Density functional theory (DFT) calculations and the natural bond orbital (NBO) analysis were conducted to give insights into the electronic structure of 1 and the bonding characters of the OCF3 group. The reactivity of 1 towards trifluoromethoxylation of organic halides was also examined; a reaction with benzyl bromides gave the desired products of benzyl trifluoromethyl ethers in good to excellent yields. [ABSTRACT FROM AUTHOR]

Efficiently selective co-crystallization strategy of sucrose-6-acetate (SA-6) from the complicated sucrose acylation mixture and facial co-former removal have been developed, which were driven by thermally stable co-crystals, proper solvent size and acid-base coupling. [Display omitted] • An efficiently selective co-crystallization separation of sucrose-6-acetate (SA-6) from the complicated sucrose acylation mixture can be realized by HAc, which can be facially removed by triethylamine. • The crystal structure of SA-6·HAc co-crystal has been determined, whose 3D hydrogen-bonding network is constructed from the SA-6 layers inserted by HAc with cavity size of 5.56 × 7.54 Å. • The optimizations on co-crystallization and co-former removal have been conducted, based on which the high SA-6 separation efficiency of 90.33 % in 1.5 h can be achieved. The purity of SA-6 can meet with the commercial requirement. • The mechanisms were proposed based crystal structure and theoretical calculations, in which thermally stable co-crystals, proper solvent size and acid-base coupling drive these processes. The searching for the facial and highly efficient separation method of sucrose-6-acetate (SA-6) in the acylation process seems significant for the production of sucralose. In this work, an efficiently selective co-crystallization strategy of SA-6 from the complicated sucrose acylation mixture has been developed, i. e. firstly, selective co-crystallization using acetic acid (HAc) as a cheap and green co-former (operation I), and co-former removal by triethylamine (TEA) (operation II). The crystal structure of SA-6·HAc co-crystal in the operation I has been determined, it is a 3D hydrogen-bonding network with HAc inserting among the SA-6 layers, whose cavity size is 5.56 × 7.54 Å. And the optimization on two operations have been conducted, including HAc dosage, solvent/aliphatic amine types and dosage, separation time/temperature. Based on the optimal conditions, the high SA-6 separation efficiency of 90.33 % in 1.5 h can be achieved, during which relative selectivity coefficient (α X) is lower than 0.003, deacidification ratio (δ) is higher than 99.47 %, and the product purity is 99.86 % (wt). Furthermore, the selective co-crystallization and co-former removal mechanisms were proposed base on crystal structure and theoretical calculations, in which thermally stable co-crystals, proper solvent size and acid-base coupling drive these processes. This strategy can enhance the separation efficiency of acylation process in sucralose production greatly. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the improved protocol for α-trifluoromethylthio-substituted ketones synthesis through α-bromo ketones copper-mediated trifluoromethylthiolation.

Alkali metals were introduced into heavy main-group iodometallates to get two new IA/IVAheterometallic frameworks [PbIK(pdon)(HO)] ( 1) and {[Pb I K(pdon)(HO)] ⋅ HO} ( 2) (pdon =1,10-phenanthroline-5,6-dione), which were obtained as single phases by hydrothermal method at different pH values. Compounds 1 and 2 are three-dimensional heterometallic frameworks constructed from the linkage of pdon ligand between iodometallate chains and potassium oxides/iodide clusters. Specially, these two heterometallic frameworks exhibit broadened absorption bands at 700 and 750 nm compared with those of bulk PbI and pdon ligand. The band gap of 2 is wider than that of 1, which is due to the absence of π⋯ π interaction in 2. Their thermal stabilities are also discussed. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: The absorption and the emission spectra of GaN and (Ga,AE)N (AE=Be, Mg, Ca) were calculated by using TDDFT method with cluster model. The calculation results show that Ga26N26H50 cluster only has very weak absorption but has some emission bands in visible region. The band-to-band emission appears around 3.56eV. If alkaline-earth atoms (Be, Mg and Ca) are doped into GaN, the blue emission band around 3.0eV appears. Thereinto, Ga25Ca1N26H50 cluster shows a weaker yellow emission band and a stronger blue one (2.92eV), which make (Ga,Ca)N material a promising candidate to emit blue light. [Copyright &y& Elsevier]

Social competition plays a pivotal role in determining individuals' social status. While the dorsomedial prefrontal cortex (dmPFC) is essential in regulating social competition, it remains unclear how information is processed within its local networks. Here, by applying optogenetic and chemogenetic manipulations in a dominance tube test, we reveal that, in accordance with pyramidal (PYR) neuron activation, excitation of the vasoactive intestinal polypeptide (VIP) or inhibition of the parvalbumin (PV) interneurons induces winning. The winning behavior is associated with sequential calcium activities initiated by VIP and followed by PYR and PV neurons. Using miniature two-photon microscopic (MTPM) and optrode recordings in awake mice, we show that VIP stimulation directly leads to a two-phased activity pattern of both PYR and PV neurons—rapid suppression followed by activation. The delayed activation of PV implies an embedded feedback tuning. This disinhibitory VIP-PV-PYR motif forms the core of a dmPFC microcircuit to control social competition. [Display omitted] • Activation of VIP or inhibition of PV interneurons in dmPFC induces winning • Inhibition of VIP or activation of PV interneurons in dmPFC induces losing • Calcium activities of dmPFC VIP neurons lead those of PYR and PV neurons in winning • MTPM and optrode recordings reveal a disinhibitory VIP-PV-PYR microcircuit in dmPFC How the dorsomedial prefrontal cortex (dmPFC) computes complex information in social competition within its local network is unclear. Here, Zhang et al. reveal a dynamic disinhibitory microcircuit, involving dmPFC VIP+, PV+, and pyramidal neurons, that controls social competition in the dominance tube test. [ABSTRACT FROM AUTHOR]

The increasing dangerous chemical pollutants led by shipping accidents call for the new pollutant treatment strategy. In this work, a new three-component hybrid {[(BiI6)I13]·2I3·(H-BPA)4}n (1) can be used in dye degradation in seawater. The highly interesting feature of 1 lies in its unique 1-D Z-shape [(BiI6)I13]n6− infinite chain constructed from the I···I contacts between mono-nuclear (BiI6)3− anions and I133− polyiodide anions. Finally, the hydrogen bonds between [(BiI6)I13]n6− polyanions and H-BPA2+ cations contribute to the formation a quasi-3-D network. Specifically, 1 exhibits the wide absorption zone from ultraviolet to visible regions and high charge-separation efficiency, hinting its application in visible-light catalysis. As expected, 1 represents photocatalytic activity for the degradation of rhodamine B in seawater with degradation ratio of 90%, and the photocatalytic performance is stable. This work might provide new photocatalytic material for pollutant treatment in shipping accidents. [ABSTRACT FROM AUTHOR]

Light exerts profound effects on cognitive functions across species, including humans. However, the neuronal mechanisms underlying the effects of light on cognitive functions are poorly understood. In this study, we show that long-term exposure to bright-light treatment promotes spatial memory through a di-synaptic visual circuit related to the nucleus reuniens (Re). Specifically, a subset of SMI-32-expressing ON-type retinal ganglion cells (RGCs) innervate CaMKIIα neurons in the thalamic ventral lateral geniculate nucleus and intergeniculate leaflet (vLGN/IGL), which in turn activate CaMKIIα neurons in the Re. Specific activation of vLGN/IGL-projecting RGCs, activation of Re-projecting vLGN/IGL neurons, or activation of postsynaptic Re neurons is sufficient to promote spatial memory. Furthermore, we demonstrate that the spatial-memory-promoting effects of light treatment are dependent on the activation of vLGN/IGL-projecting RGCs, Re-projecting vLGN/IGL neurons, and Re neurons. Our results reveal a dedicated subcortical visual circuit that mediates the spatial-memory-promoting effects of light treatment. • Activation of Re-projecting vLGN/IGL neurons activates neuronal activity in the Re • SMI-32+ ON-type RGCs directly innervate the vLGN/IGL-Re pathway • Activation of the retina-vLGN/IGL-Re pathway promotes spatial memory • Light treatment promotes spatial memory via the retina-vLGN/IGL-Re pathway Huang et al. identified a visual circuit related to the Re that regulates spatial memory. They demonstrate that the retina-vLGN/IGL-Re pathway mediates the spatial-memory-promoting effects of light treatment. [ABSTRACT FROM AUTHOR]

• A method is proposed to establish concrete models with a high ratio of aggregates. • The constraints surrounding the concrete model are considered. • The cracking behaviors of concrete due to non-uniform rebar corrosion are studied. • The effects of aggregate, cover thickness, rebar, tensile strength are analyzed. Concrete cracking due to rebar corrosion is an important engineering pathology. Most of the numerical studies were based on the concrete models with normal volume ratios of aggregates and didn't consider the surrounding constraints. We propose a new algorithm to generate aggregates of a high volume ratio and establish the meso-scale concrete model with consideration of the surrounding constraints. The model is verified against available experimental results. Then, a series of simulations are carried out to analyze the failure pattern of concrete caused by non-uniform rebar corrosion. The influences of surrounding structures, spatial and size distributions of aggregates, cover thickness, rebar diameter, and concrete tensile strength are discussed. [ABSTRACT FROM AUTHOR]

Summary Orchestration of sleep and feeding behavior is essential for organismal health and survival. Although sleep deprivation promotes feeding and starvation suppresses sleep, the underlying neural mechanisms remain largely unknown. Here, we showed that starvation in mice potently promoted arousal and activated calretinin neurons (CR+) in the paraventricular thalamus (PVT). Direct activation of PVTCR+ neurons promoted arousal, and their activity was necessary for starvation-induced sleep suppression. Specifically, the PVTCR+-bed nucleus of the stria terminalis (BNST) circuit rapidly initiated arousal. Selective inhibition of BNST-projecting PVT neurons opposed arousal during starvation. Taken together, our results define a cell-type-specific neural circuitry modulating starvation-induced arousal and coordinating the conflict between sleeping and feeding. Highlights • Starvation increases wakefulness and modulates PVT neuronal activity • PVTCR+ neuronal activity is necessary for starvation-induced arousal • PVT-BNST circuit inhibition attenuates arousal in the starved state Hua et al. show that starvation increases wakefulness and modulates the paraventricular thalamus (PVT) neuronal activity. Optoactivation of PVT calretinin neurons promotes arousal, and their activity is necessary for starvation-induced sleep suppression. They also suggest that the PVT-BNST circuit is required for starvation-induced arousal. [ABSTRACT FROM AUTHOR]

Adult hippocampal neurogenesis is crucial for preserving normal brain function, but how it is regulated by niche cells is uncertain. Here we show that β-arrestin 1 (β-arr1) in dentate gyrus (DG) regulates neural precursor proliferation. β-arr1 knockout (KO) mice show reduced neural precursor proliferation in subgranular zone (SGZ) which could be rescued by selective viral expression of β-arr1 but not its nuclear-function-deficient mutants under control of hGFAP promotor in DG. Compared with wild type astrocytes, β-arr1 KO astrocytes nurture less neurospheres, and this may be attributed to changed activity of soluble, heat-sensitive excretive factors, such as BMP2. RNA-sequencing reveals that β-arr1 KO DG astrocytes exhibit an aberrant gene expression profile of niche factors, including elevated transcription of Bmp2. Taken together, our data suggest that β-arr1 mediated nuclear signaling regulates the production of excretive factors derived from niche astrocytes and expansion of neural precursors in DG, thus maintaining homeostasis of adult hippocampal neurogenesis. [ABSTRACT FROM AUTHOR]