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Tourmaline is known for its natural negative ion effect and far-infrared radiation function, which promote human blood circulation, relieve pain, regulate the endocrine system, and enhance immunity and other functions. These functions motivate the use of this material for enhanced sensitivity of wearable sensors. In this work, taking advantage of the unique multifunctions of tourmaline nanoparticles (Tur), highly boosted piezoelectricity was achieved by incorporating polydopamine (PDA)-modified Tur in PVDF. The PDA@Tur nanofillers not only effectively increased the ß-phase content of PVDF but also played a major role in significantly enhancing piezoelectricity, wettability, elasticity, air permeability, and stability of the piezoelectric sensors. Especially, the maximum output voltage of the fiber membrane with 0.5 wt % PDA@Tur reached 31.0 V, being 4 times that of the output voltage of the pure PVDF fiber membrane. Meanwhile, the sensitivity reached 0.7011 V/kPa at 1-10 N, which was 3.6 times that of pure PVDF film (0.196 V/kPa). The power intensity reached 8 µW/cm2, being 5.55 times that of the pristine PVDF PENG (1.44 µW/cm2), and the piezoelectric coefficient from d33 m/PFM is 5.5 pC/N, higher than that of pristine PVDF PENG (3.1 pC/N). Output signal graphs corresponding to flapping, finger, knee, and elbow movements were detected. The response/recovery time of the sensor device was 24/19 ms. The piezoelectric nanogenerator (PENG) was capable of charging multiple capacitors to 2 V within a short time and lighting up 15 light-emitting diodes bulbs (LEDs) simultaneously with a single beat. In addition, a 4 × 4 row-column multiplexed sensor array was made of PENGs, which showed distinct responses to different stress areas in different sensor modules. This study demonstrated high-performance PDA@Tur PVDF-based PENG being capable of energy harvesting and sensing, providing a guideline for the design and buildup of wearable self-powered devices in healthcare and human-computer interaction.

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Optofluidic systems, integrating microfluidic and micro-optical technologies, have emerged as transformative tools for various applications, from molecular detection to flow cytometry. However, existing optofluidic microlenses often rely on external forces for tunability, hindering seamless integration into systems. This work presents an approach using two-photon polymerization (TPP) to fabricate inherently tunable microlens arrays, eliminating the need for supplementary equipment. The optofluidic design incorporates a three-layered structure enabling dynamic manipulation of refractive indices within microchannels, leading to tunable focusing characteristics. It is shown that the TPP fabricated optofluidic microlenses exhibit inherent tunable focal lengths, numerical apertures, and spot sizes without reliance on external forces. This work signifies some advancements in optofluidic technology, offering precise and tunable microlenses with potential applications in adaptive imaging and variable focal length microscopy.

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Current methods for the protection of metal surfaces utilize harsh chemical processes, such as organic paint or electro-plating, which are not environment-friendly and require extensive waste treatments. In this study, a two-step approach consisting of electrochemical assisted deposition (EAD) of an aqueous silane solution and a dip coating of a low surface energy silane for obtaining a superhydrophobic self-cleaning surface for the enhanced protection of copper substrate is presented. A porous and hierarchical micro-nanostructured silica basecoat (sol-gel) was first formed by EAD of a methyltriethoxysilane (MTES) precursor solution on a copper substrate. Then, a superhydrophobic top-coat (E-MTES/PFOTS) was prepared with 1H,1H,2H,2H-Perfluorooctyltriethoxysilane (PFOTS) for low surface energy. The superhydrophobic coating exhibited anti-stain properties against milk, cola, and oil, with contact angles of 151°, 151.5°, and 129°, respectively. The EAD deposition potential and duration were effective in controlling the microscopic morphology, surface roughness, and coating thickness. The E-MTES/PFOTS coatings exhibited chemical stability against acids, bases, and abrasion resistance by sandpaper. The proposed 2-layer coating system exhibited strong chemical bonding at the two interfaces and provided a brush-like surface morphology with long-lasting superhydrophobicity. The developed method would provide an environment-friendly and expedient process for uniform protective coatings on complex surfaces.

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Silicon photonics is rapidly evolving as an advanced chip framework for implementing quantum technologies. With the help of silicon photonics, general-purpose programmable networks with hundreds of discrete components have been developed. These networks can compute quantum states generated on-chip as well as more extraordinary functions like quantum transmission and random number generation. In particular, the interfacing of silicon photonics with complementary metal oxide semiconductor (CMOS) microelectronics enables us to build miniaturized quantum devices for next-generation sensing, communication, and generating randomness for assembling quantum computers. In this review, we assess the significance of silicon photonics and its interfacing with microelectronics for achieving the technology milestones in the next generation of quantum computers and quantum communication. To this end, especially, we have provided an overview of the mechanism of a homodyne detector and the latest state-of-the-art of measuring squeezed light along with its integration on a photonic chip. Finally, we present an outlook on future studies that are considered beneficial for the wide implementation of silicon photonics for distinct data-driven applications with maximum throughput.

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It is proven that introduction of graphene into typical heterostructures can effectively reduce the high interfacial thermal resistance in semiconductor chips. The crystallinity of graphene varies greatly; thus, we have investigated the effects of single-crystal and polycrystalline graphene on the thermal transport of AlN/graphene/3C-SiC heterostructures by molecular dynamics. The results show that polycrystalline graphene contributes more to the interfacial thermal conductance (ITC) inside the chip with a maximum increase of 75.09%, which is further confirmed by the energy transport and thermal relaxation time. Multiple analyses indicate that grain boundaries lead to the increase in C-Si covalent bonds, and thus, strong interactions improve the ITC. However, covalent bonding further causes local tensile strain and wrinkles in graphene. The former decreases the ITC, and the latter leads to the fluctuation of the van der Waals interaction at the interface. The combined effect of various influential factors results in the increase in the ITC, which are confirmed by phonon transmission with 0-18 THz. In addition, wrinkles and covalent bonding lead to increased stress concentration in polycrystalline graphene. This leads to a maximum reduction of 19.23% in the in-plane thermal conductivity, which is not conducive to the lateral diffusion of hot spots within the chip. The research results would provide important guidance in designing for high thermal transport performance high-power chips.

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In this paper, we preliminarily propose the dissipative sliding mode control (SMC) scheme for polyhedral singular semi-Markov jump linear parameter varying (SS-MJLPV) systems considering deception attacks between the sensor and controller. The main feature of this scheme is that a novel developed parameter dependent integral-type SMC law follows the changes of the system. Note that the mode of the sliding mode controller is not synchronized with the system mode, and the transition rates (TRs) of the system are assumed to be unknown. Moreover, we extend the previous work concerning the static event-triggered transmission protocol (ETP) to the dynamic one, in which the triggering threshold is dynamically updated via the internal-dynamic-variable. Finally, a DC-motor model is presented to illustrate the correctness of the developed results.

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Dust pollution presents a wide range of adverse effects to product functionalities and the quality of human life. For instance, when dust particles deposit on solar photovoltaic panels, sunlight absorption is significantly reduced, and solar-to-electrical energy conversion yield may be lowered by 51%- Conventional (manual) dust removal methods are costly, consume significant material resources, and cause irreparable damage to the solar glass surface. Therefore, it is critical to develop glass surfaces that can clean themselves or are easily cleaned by natural forces. Many approaches have been attempted to reduce dust deposition, such as developing superhydrophobic surfaces and preparing anti-static surfaces. This paper reviews the recent progress in studies of anti-dust and cleaning mechanisms or methodologies, which include investigation into micro- and nano-sized dust properties, dust deposition processes and adhesion mechanisms to surfaces, and the state-of-the-art approaches to anti-dust and easy-cleaning functions that tailor surface micro-/nanotextures, lowering surface energy via nanocoatings, and enhancing anti-static properties with nanomaterials. We compare the advantages and disadvantages of various approaches and discuss the research prospects. We envision that future research will be focused on developing transparent surfaces with multiple dust-proof functions to cope with dust-burdening operating environments.

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In this study, we sequenced and analyzed the complete mitochondrial genome of Rhodoprasina callantha Jordan, 1929. The complete mitochondrial genome sequence of R. callantha was 15,343 bp in size and encoded 13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNA), 22 transfer RNA genes (tRNA) and one control region (CR). The nucleotide composition of mitogenome was highly biased to A and T. Most protein-coding genes (PCGs) initiate with the standard start codon of ATN and terminate with the typical stop codon TAA/TAG. The phylogeny of Sphingidae based on nucleotide sequences of PCGs recovered the monophyly of subfamilies of Sphingidae with high support values. Langinae was the first subfamily diverged in Sphingidae, which was in accordance with previous study. R. callantha was the member of subfamily Smerinthinae, and closely related to the genus Marumba.

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In this study, we sequenced and analyzed the complete mitochondrial genome of Ambulyx tobii to compare mitochondrial genome structures and reconstruct phylogenetic relationships. The complete mitochondrial genome sequence of A. tobii is circular, 15,343 bp in size and encodes 13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and a control region (CR). Nucleotide composition is highly biased toward A + T nucleotides (81.2%). Most PCGs initiate with the standard start codon of ATN and terminate with the typical stop codon TAA/TAG. Phylogenetic analyses were performed using both 13 PCGs and whole mitochondrial genomes showed that A. tobii is closely related to A. substrigilis.

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Based on nonequilibrium molecular dynamics (NEMD) and nonequilibrium Green's function simulations, the interfacial thermal conductance (ITC) of graphene/h-BN in-plane heterostructures with near-interface defects (monovacancy defects, 585 and f5f7 double-vacancy defects) is studied. Compared to pristine graphene/h-BN, all near-interface defects reduce the ITC of graphene/h-BN. However, differences in defective structures and the wrinkles induced by the defects cause significant discrepancies in heat transfer for defective graphene/h-BN. The stronger phonon scattering and phonon localization caused by the wider cross-section in defects and the larger wrinkles result in the double-vacancy defects having stronger energy hindrance effects than the monovacancy defects. In addition, the approximate cross-sections and wrinkles induced by the 585 and f5f7 double-vacancy defects provide approximate heat hindrance capability. The phonon transmission and vibrational density of states (VDOS) further confirm the above results. The double-vacancy defects in the near-interface region have lower low-frequency phonon transmission and VDOS values than the monovacancy defects, while the 585 and f5f7 double-vacancy defects have similar low-frequency phonon transmission and VDOS values at the near-interface region. This study provides physical insight into the thermal transport mechanisms in graphene/h-BN in-plane heterostructures with near-interface defects and provides design guidelines for related devices.

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Walnut peptides have been reported to exhibit diverse activities. In this study, we investigated the protective and recovery effects of the walnut derived peptide leucine-proline-phenylalanine (LPF) on dextran sulfate sodium (DSS)-induced colitis in mice. The peptide LPF mitigated the severity of symptoms during the development phase of colitis, as evidenced by changes in body weight, disease activity index score, and serum inflammatory cytokine levels. Moreover, the treatment groups showed beneficial effects, including increased colon length, reduced colonic cell apoptosis, decreased production of inflammatory factors, and expansion of splenic regulatory T cells during the recovery period. Additionally, 16S rDNA sequencing results indicated that 100 mg/kg LPF (M group) reversed the dysbiosis of gut microbiota in colitis mice. This included partial recovery of diversity of microbiota, increase in relative abundance of the family Lachnospiraceae and Ruminococcaceae during the development phase of colitis. Additionally, the composition of gut microbiota in the M group was constantly improved during the recovery period of colitis, showing increased relative abundance of beneficial genera and decreased abundance of potentially harmful genera compared with that in the DSS group. In summary, the peptide LPF could contribute to remission of colitis symptoms and restoration through reduction in cell apoptosis, anti-inflammatory effects, and regulation of gut microbiota.

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Bacterial biofilms formed on touchable surfaces such as displays of electronic devices not only reduce the product service life, but also cause human health issues. There is an urgent need to research the biofilm formation mechanism and methodologies to prevent formation of biofilms on human touchable surfaces. It has been reported that laser-induced graphene (LIG) helps resist biofilm growth, which has been attributed to the atomic composition and sharp edges of graphene. However, LIG alone was not able to retard bacterial growth completely. It has been reported that LIG incorporated with silver (Ag) nanoparticles exhibited enhanced surface antibacterial activity. As a heavy metal, overdose of Ag is harmful to human health. Therefore, a new biocompatible antibacterial agent to replace or reduce the use of Ag is highly important. In this study, we investigate and compare the effect of LIG doped with two types of nanocrystals, i.e., ZnO and silver (Ag)-doped ZnO, on antibacterial actions. A 355 nm ultraviolet (UV) laser was used to produce LIG on a watercolor paper substrate. Formation of few-layer graphene has been verified by Raman spectra. Escherichia coli (E. coli), a representative of Gram-negative bacteria and Staphylococcus aureus (S. aureus), a representative of Gram-positive bacteria were employed for the investigation of the bacteriostatic properties of the LIG paper substrate. Results show that with the incorporation of either the ZnO nanocrystals or the silver (Ag)-doped ZnO nanocrystals into LIG, the antibacterial effect became stronger. It is further shown that the Ag-doped ZnO nanocrystals have superior antibacterial performance to that of the ZnO nanocrystals. The Ag-doped ZnO nanocrystals are potentially an effective and biocompatible antibacterial agent and yet have a much reduced and acceptable level of Ag concentration.

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Thirty-six new α-benzylidene-γ-lactone compounds based α-methylene-γ-butyrolactone substructure were prepared and characterized by spectroscopic analysis. All compounds were evaluated for antifungal activities in vitro against six plant pathogenic fungi and the half maximal inhibitory concentration (IC50) against Botrytis cinerea and Colletotrichum lagenarium were investigated. Compounds 5c-3 and 5c-5 with the halogen atom exhibited excellent fungicidal activity against B. cinerea (IC50=22.91, 18.89µM). The structure-activity relationships (SARs) analysis indicated that the derivatives with electron-withdrawing substituents at the meta- or para-positions improves the activity. Via the heuristic method, the generated quantitative structure-activity relationship (QSAR) model (R2=0.961) revealed a strong correlation of antifungal activity against B. cinerea with molecular structures of these compounds. Meanwhile, the cytotoxicity of 20 representative derivatives was tested in the human tumor cells line (HepG2) and the hepatic L02 cells line, the result indicated that the synthesized compounds showed significant inhibitory activity and limited selectivity. Compound 5c-5 has the highest fungicidal activity with IC50=18.89µM (against B. cinerea.) but low cytotoxicity with IC50=35.4µM (against HepG2 cell line) and IC50=68.8µM (against Hepatic L02 cell line). These encouraging results can be providing an alternative, promising use of α-benzylidene-γ-lactone through the design and exploration of eco-friendly fungicides with low toxicity and high efficiency.

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In consideration of the fact that the α-methylene-γ-butyrolactone moiety is a major bio-functional group in the structure of carabrone and possesses some agricultural biological activity, forty-six new ester and six new ether derivatives containing α-methylene-γ-butyrolactone moieties were synthesized, and their fungicidal activities against Colletotrichum lagenarium and Botrytis cinerea were investigated. Most of the synthesized compounds showed moderate to significant fungicidal activity. Among them, halogen atom-containing derivatives showed better activity than others, especially compounds 6a,d which exhibited excellent fungicidal activity against C. lagenarium, with IC50 values of 7.68 and 8.17 µM. The structure-activity relationship (SAR) analysis indicated that ester derivatives with electron-withdrawing groups on the benzene ring showed better fungicidal activity than those with electron-donating groups. A quantitative structure-activity relationship (QSAR) model (R² = 0.9824, F = 203.01, S² = 0.0083) was obtained through the heuristic method. The built model revealed a strong correlation of fungicidal activity against C. lagenarium with the molecular structures of these compounds. These results are expected to prove helpful in the design and exploration of low toxicity and high efficiency α-methylene-γ-butyrolactone-based fungicides.

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