Universal Murray's law for optimised fluid transport in synthetic structures.

Materials following Murray's law are of significant interest due to their unique porous structure and optimal mass transfer ability. However, it is challenging to construct such biomimetic hierarchical channels with perfectly cylindrical pores in synthetic systems following the existing theory. Achieving superior mass transport capacity revealed by Murray's law in nanostructured materials has thus far remained out of reach. We propose a Universal Murray's law applicable to a wide range of hierarchical structures, shapes and generalised transfer processes. We experimentally demonstrate optimal flow of various fluids in hierarchically planar and tubular graphene aerogel structures to validate the proposed law. By adjusting the macroscopic pores in such aerogel-based gas sensors, we also show a significantly improved sensor response dynamics. In this work, we provide a solid framework for designing synthetic Murray materials with arbitrarily shaped channels for superior mass transfer capabilities, with future implications in catalysis, sensing and energy applications.

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Vertical greenery system (VGS) is a sustainable solution to promote building energy saving and emission reduction, mitigate the urban heat island effect, as well as a crucial component of urban ecological construction. We summarized four main mechanisms of the thermal effects of VGSs, including shading effect, evapotranspiration effect, thermal insulation effect, and wind control effect. We elucidated the effects of VGSs on building cooling and energy saving, and analyzed the cooling effects of VGSs on plant canopy and outdoor ambient air, as well as their influence on mitigating the urban heat island effect. Based on available research on the thermal effects of VGSs, we identified key directions for future research, aiming to expedite the development of green cities and achieve carbon neutrality.

Single-Transistor Neuron with Excitatory-Inhibitory Spatiotemporal Dynamics Applied for Neuronal Oscillations.

Brain-inspired neuromorphic computing systems with the potential to drive the next wave of artificial intelligence demand a spectrum of critical components beyond simple characteristics. An emerging research trend is to achieve advanced functions with ultracompact neuromorphic devices. In this work, a single-transistor neuron is demonstrated that implements excitatory-inhibitory (E-I) spatiotemporal integration and a series of essential neuron behaviors. Neuronal oscillations, the fundamental mode of neuronal communication, that construct high-dimensional population code to achieve efficient computing in the brain, can also be demonstrated by the neuron transistors. The highly scalable E-I neuron can be the basic building block for implementing core neuronal circuit motifs and large-scale architectural plans to replicate energy-efficient neural computations, forming the foundation of future integrated neuromorphic systems.

Immune-Enhancing Effects of a Novel Glucan from Purple Sweet Potato Ipomoea batatas (L.) Lam on RAW264.7 Macrophage Cells via TLR2- and TLR4-Mediated Pathways.

PSPP-1 was obtained from purple sweet potato, and the effects of PSPP-1 on the immune modulation on macrophage cells were investigated for the first time. PSPP-1 promoted RAW264.7 proliferation and increased the total cell percentage in DNA synthesis and mitosis phases, and the cell morphology changed in volume and appearance. Additionally, the RAW264.7 immune functions of phagocytic activity and nitric oxide, reactive oxygen species, and cytokine production were improved by PSPP-1. The western blot experiment showed that PSPP-1 could activate toll-like receptor 2 and toll-like receptor 4-mediated pathways, and the expressions of proteins in MyD88-dependent, mitogen-activated protein kinase (MAPK)-signaling, NF-κB-signaling, AP-1 signaling, and TRIF-dependent pathways were improved markedly. Molecular docking and Biolayer Interferometry study further indicated that PSPP-1 could recognize and bind TLR2 and TLR4 by targeting the binding sites with a strong affinity. It suggested that PSPP-1 could enhance immunity via TLR2- and TLR4-mediated pathways, and it could be explored as an immunomodulatory agent.

Purification, characterization, and in vitro antitumor activity of a novel glucan from the purple sweet potato Ipomoea Batatas (L.) Lam.

A novel glucan PSPP-1 (18.3 kDa) was purified from the foot tuber of purple sweet potato Ipomoea Batatas (L.) Lam. Its backbone was composed of →4)-α-d-Glcp(1→ glycosyl, and branching at the O-2, O-3, and O-6 positions with α-d-Glcp(1→ residues. X-ray diffraction experiment showed that PSPP-1 existed as an amorphous form. Its microstructure was detected via scanning electron microscopy. Its particle size was mainly concentrated at 230 nm in water. Congo red and circular dichroism experiments showed there was no triple-helix conformation. Atomic force microscopy data suggested that its height and width ranged from 1.0 to 6.1 nm and 65 to 210 nm, respectively; its maximum ring diameter and chain length was ∼800 nm and ∼7.0 µm, respectively. Furthermore, it exhibited inhibitory activities on HepG2, LOVO, and MCF-7 cells. Collectively, our data are useful for understanding the structural characteristics of sweet potato polysaccharides, and their application in foods and pharmaceutical areas.

Modulation of Binary Neuroplasticity in a Heterojunction-Based Ambipolar Transistor.

To keep pace with the upcoming big-data era, the development of a device-level neuromorphic system with highly efficient computing paradigms is underway with numerous attempts. Synaptic transistors based on an all-solution processing method have received growing interest as building blocks for neuromorphic computing based on spikes. Here, we propose and experimentally demonstrated the dual operation mode in poly{2,2-(2,5-bis(2-octyldodecyl)-3,6-dioxo-2,3,5,6-tetrahydropyrrolo[3,4-c]pyrrole-1,4-diyl)dithieno[3,2-b]thiophene-5,5-diyl-alt-thiophen-2,5-diyl}(PDPPBTT)/ZnO junction-based synaptic transistor from ambipolar charge-trapping mechanism to analog the spiking interfere with synaptic plasticity. The heterojunction formed by PDPPBTT and ZnO layers serves as the basis for hole-enhancement and electron-enhancement modes of the synaptic transistor. Distinctive synaptic responses of paired-pulse facilitation (PPF) and paired-pulse depression (PPD) were configured to achieve the training/recognition function for digit image patterns at the device-to-system level. The experimental results indicate the potential application of the ambipolar transistor in future neuromorphic intelligent systems.

Near-Infrared Annihilation of Conductive Filaments in Quasiplane MoSe2 /Bi2 Se3 Nanosheets for Mimicking Heterosynaptic Plasticity.

It is desirable to imitate synaptic functionality to break through the memory wall in traditional von Neumann architecture. Modulating heterosynaptic plasticity between pre- and postneurons by another modulatory interneuron ensures the computing system to display more complicated functions. Optoelectronic devices facilitate the inspiration for high-performance artificial heterosynaptic systems. Nevertheless, the utilization of near-infrared (NIR) irradiation to act as a modulatory terminal for heterosynaptic plasticity emulation has not yet been realized. Here, an NIR resistive random access memory (RRAM) is reported, based on quasiplane MoSe2 /Bi2 Se3 heterostructure in which the anomalous NIR threshold switching and NIR reset operation are realized. Furthermore, it is shown that such an NIR irradiation can be employed as a modulatory terminal to emulate heterosynaptic plasticity. The reconfigurable 2D image recognition is also demonstrated by an RRAM crossbar array. NIR annihilation effect in quasiplane MoSe2 /Bi2 Se3 nanosheets may open a path toward optical-modulated in-memory computing and artificial retinal prostheses.

Photonic Synapses Based on Inorganic Perovskite Quantum Dots for Neuromorphic Computing.

Inspired by the biological neuromorphic system, which exhibits a high degree of connectivity to process huge amounts of information, photonic memory is expected to pave a way to overcome the von Neumann bottleneck for nonconventional computing. Here, a photonic flash memory based on all-inorganic CsPbBr3 perovskite quantum dots (QDs) is demonstrated. The heterostructure formed between the CsPbBr3 QDs and semiconductor layer serves as a basis for optically programmable and electrically erasable characteristics of the memory device. Furthermore, synapse functions including short-term plasticity, long-term plasticity, and spike-rate-dependent plasticity are emulated at the device level. The photonic potentiation and electrical habituation are implemented and the synaptic weight exhibits multiple wavelength response from 365, 450, 520 to 660 nm. These results may locate the stage for further thrilling novel advances in perovskite-based memories.

Synergies of Electrochemical Metallization and Valance Change in All-Inorganic Perovskite Quantum Dots for Resistive Switching.

The in-depth understanding of ions' generation and movement inside all-inorganic perovskite quantum dots (CsPbBr3 QDs), which may lead to a paradigm to break through the conventional von Neumann bottleneck, is strictly limited. Here, it is shown that formation and annihilation of metal conductive filaments and Br- ion vacancy filaments driven by an external electric field and light irradiation can lead to pronounced resistive-switching effects. Verified by field-emission scanning electron microscopy as well as energy-dispersive X-ray spectroscopy analysis, the resistive switching behavior of CsPbBr3 QD-based photonic resistive random-access memory (RRAM) is initiated by the electrochemical metallization and valance change. By coupling CsPbBr3 QD-based RRAM with a p-channel transistor, the novel application of an RRAM-gate field-effect transistor presenting analogous functions of flash memory is further demonstrated. These results may accelerate the technological deployment of all-inorganic perovskite QD-based photonic resistive memory for successful logic application.

[Experimental study on the antiviral mechanism of Ceratostigma willmattianum against herpes simplex virus type 1 in vitro].

OBJECTIVE: To study the antiviral effect and mechanisms of the liquid extract from Ceratostigma willmattianum against herpes simplex virus type 1 (HSV-1) in vitro. METHOD: C. willmattianum in various concentration was applied to different steps of HSV-1 replication cycle. 50% Tissue culture infective dose (TCID50), cytopathic effect (CPE), MTT staining method, dot blotting and Northern blotting analysis were used to estimate index of antiviral activity. RESULT: 50% Toxic concentration (TC50) was 1077 mg x L(-1), IC50 29.46 mg x L(-1) and therapeutic index (TI) 36.56 in C. willmattianum. TC50 330 mg x L(-1), 50% Inhibiting concentration (IC50) 9.12 mg x L(-1) and TI 36.18 in ACV by MTT staining method. The liquid extract from C. willmattianum had remarkable effect on inhibiting HSV-1 in vitro. Ceratostigma could interfere absorption of HSV-1 to Vero cells to prevent HSV-1 infectivity, inhibit HSV-1 gD DNA replication and HSV-1 gD mRNA expression. CONCLUSION: C. willmattianum possesses strong anti-HSV-1 activity in vitro. The antiviral mechanisms are related to inhibiting virus absorption, HSV-1 gD gene replication and HSV-1 gD gene transcription.