Carbon Nanotube Films with Fewer Impurities and Higher Conductivity from Aqueously Mono-Dispersed Solution via Two-Step Filtration for Electric Heating.

With the intensification of global climate problems, electric heating has recently attracted much attention as a clean and low-carbon heating method. Carbon nanotubes (CNTs) are an ideal medium for electric heating applications due to their excellent mechanical, electrical, and thermal properties. The preparation of electrothermal films based on an aqueous CNT dispersion as a raw material is environmentally friendly. However, in the traditional one-step filtration method, the residual excess dispersant and the small aspect ratio of the CNTs in the preparation process limit the performance of electrothermal CNT films. In this paper, we report a two-step filtration method that removes the free dispersant and small CNTs in the first filtration step and obtains denser CNT films by controlling the pores of the filter membrane in the second filtration step. The results suggest that, compared to the CNT1 film obtained from one-step filtration, the CNT1-0.22 film, obtained from two-step filtration using 1 and 0.22 µm membranes, has a smoother and flatter surface, and the surface resistance is 80.0 Ω sq-1, which is 29.4% lower. The convective radiation conversion efficiency of the CNT1-0.22 film is 3.36 mW/°C, which is 36.1% lower. We anticipate that such CNT films could be widely applied in building thermal insulation and underfloor heating.

Secure and decentralized federated learning framework with non-IID data based on blockchain.

Federated learning enables the collaborative training of machine learning models across multiple organizations, eliminating the need for sharing sensitive data. Nevertheless, in practice, the data distributions among these organizations are often non-independent and identically distributed (non-IID), which poses significant challenges for traditional federated learning. To tackle this challenge, we present a hierarchical federated learning framework based on blockchain technology, which is designed to enhance the training of non-IID data., protect data privacy and security, and improve federated learning performance. The framework builds a global shared pool by constructing a blockchain system to reduce the non-IID degree of local data and improve model accuracy. In addition, we use smart contracts to distribute and collect models and design a main blockchain to store local models for federated aggregation, achieving decentralized federated learning. We train the MLP model on the MNIST dataset and the CNN model on the Fashion-MNIST and CIFAR-10 datasets to verify its feasibility and effectiveness. The experimental results show that the proposed strategy significantly improves the accuracy of decentralized federated learning on three tasks with non-IID data.

Identification and characteristic analysis of an extracellular signal-regulated kinase from Ostrinia furnacalis Guenée.

The extracellular signal-regulated kinase (ERK) pathway, a critical genetic determinant, controls diverse physiological functions, including innate immunity, development, and stress response. In the current study, a full-length cDNA (1592bp) encoding the ERK gene (OfERK) was cloned from Ostrinia furnacalis Guenée (GenBank accession number: MF797866). The open reading frame of the OfERK gene encoded 364 amino acids and shared 96.43%-98.08% amino acid identities with other insect mitogen-activated protein kinases. For spatiotemporal analysis of the expression pattern, OfERK exhibited a significant peak expression on the 3rd day of the pupa stage and showed the highest expression in hemocytes specifically. Indirect immunofluorescence assays and immuno-electron microscopy revealed a wide distribution of the OfERK protein in hemocytes and epidermis. Moreover, the results demonstrated that the Bt Cry1Ab-activated toxin significantly induces the expression of OfERK. Other genes related to immune response, development, and stress response exhibited dynamic changes in expression after Cry1Ab oral treatment. The expression of OfERK was downregulated through RNA interference, and the correlation of its expression with other related genes was verified using quantitative real-time polymerase chain reaction. Our study provides valuable insights into the regulatory mechanism of ERK in insects for future studies.

Ultrasonication-Tailored Graphene Oxide of Varying Sizes in Multiple-Equilibrium-Route-Enhanced Adsorption for Aqueous Removal of Acridine Orange.

Graphene oxide (GO) has shown remarkable performance in the multiple-equilibrium-route adsorption (MER) process, which is characterized by further activation of GO through an in-situ reduction process based on single-equilibrium-route adsorption (SER), generating new adsorption sites and achieving an adsorption capacity increase. However, the effect of GO on MER adsorption in lateral size and thickness is still unclear. Here, GO sheets were sonicated for different lengths of time, and the adsorption of MER and SER was investigated at three temperatures to remove the typical cationic dye, acridine orange (AO). After sonication, we found that freshly prepared GO was greatly reduced in lateral size and thickness. In about 30 min, the thickness of GO decreased dramatically from several atomic layers to fewer atomic layers to a single atomic layer, which was completely stripped off; after that, the monolayer lateral size reduction dominated until it remained constant. Surface functional sites, such as hydroxyl groups, showed little change in the experiments. However, GO mainly reduces the C=O and C-O bonds in MER, except for the conjugated carbon backbone (C-C). The SER adsorption kinetics of all temperatures fitted the pseudo-first-order and pseudo-second-order models, yet room temperature preferred the latter. An overall adsorption enhancement appeared as sonication time, but the equilibrium capacity of SER GO generally increased with thickness and decreased with the single-layer lateral size, while MER GO conversed concerning the thickness. The escalated temperature facilitated the exfoliation of GO regarding the adsorption mechanism. Thus, the isotherm behaviors of the SER GO changed from the Freundlich model to Langmuir as size and temperature changed, while the MER GO were all of the Freundlich. A record capacity of ~4.3 g of AO per gram of GO was obtained from the MER adsorption with a sixty-minute ultrasonicated GO at 313.15 K. This work promises a cornerstone for MER adsorption with GO as an adsorbent.

Fabrication and Thermal Performance of a Polymer-Based Flexible Oscillating Heat Pipe via 3D Printing Technology.

As flexible electronic technologies rapidly developed with a requirement for multifunction, miniaturization, and high power density, effective thermal management has become an increasingly important issue. The oscillating heat pipe, as a promising technology, was used to dissipate high heat fluxes and had a wide range of applications. In this paper, we reported the fabrication and heat transfer performance evaluation of a polymer-based flexible oscillating heat pipe (FOHP) prepared using 3D printing technology. The 3D-printed inner surface presented excellent wettability to the working fluid, which was beneficial for the evaporation of the working fluid. Ethanol was selected as the working fluid, and the influence of the filling ratios range of 30-60% on heat transfer performance was analyzed. It was found that a 3D-printed FOHP with a filling ratio of 40% presented the best heat transfer performance with the lowest thermal resistance, and the fabricated heat pipes could be easily bent from 0° to 90°. With the best filling ratio, the thermal resistance of the FOHPs increased with larger bending angles. In addition, the 3D-printed FOHP was successfully applied for the thermal management of flexible printed circuits, and the results showed that the temperature of flexible printed circuits was kept within 72 °C, and its service life was guaranteed.

Heat Transfer Performance of 3D-Printed Aluminium Flat-Plate Oscillating Heat Pipes for the Thermal Management of LEDs.

With the rapid development of electronic technologies towards high integration, high power and miniaturization, thermal management has become an increasingly important issue to guarantee the reliability and service life of electronic devices. The oscillating heat pipe (OHP), which was governed by thermally excited oscillating motion, was considered as a promising technology to dissipate high-density heat and had excellent application prospects in many important industrial processes. A flat-plate OHP, however, was fabricated by traditional welding methods, which were difficult and inefficient, resulting in increasing the cost and wasting the production time. In this work, we adopted a new metal 3D printing technology to develop an aluminum flat-plate OHP, which made it facile to build complex inner channels with high-precision molding at one time. AlSi10Mg powders, as raw materials, were selectively melted and solidified to form the container of the flat-plate OHP. The sintered inner surface presented excellent wettability to the working fluid, which facilitated the evaporation of the working fluid. Acetone was chosen as the working fluid, and the filling ratios with a range of 40-70% were loaded into the flat-plate oscillating heat pipe to analyze its effect on heat transfer performance. It was found that the 3D-printed flat-plate OHP with a 60% filling ratio had a better heat transfer performance and a lower thermal resistance, and it was able to work properly in both vertical and horizontal operation modes. The 3D-printed flat-plate OHP had been successfully applied for the thermal management of high-power LEDs, and the results showed that the temperature of LEDs was maintained within 60 °C, and its service life was prolonged.

Study on Qualitative Impact Damage of Loquats Using Hyperspectral Technology Coupled with Texture Features.

Bruising is one of the main problems in the post-harvest grading and processing of 'Zaozhong 6' loquats, reducing the economic value of loquats, and even food quality and safety problems are caused by it. Therefore, one of the main tasks in the post-harvest processing of loquats is to detect whether loquats are bruised, as well as the degree of bruising of loquats, to reduce the loss by proper treatment. An appropriate dimensionality reduction method can be used to reduce the redundancy of variables and improve the detection speed. The multispectral analysis method (MAM) has the advantage of accurate, rapid, and nondestructive detection, which was proposed to identify the different bruising degrees of loquats in this study. Firstly, the visible and near-infrared region (Vis-NIR, 400-1000 nm), the visible region (Vis, 400-780 nm), and the near-infrared region (NIR, 781-1000 nm) were analyzed using principal component analysis (PCA) to obtain the spectral regions and PC vectors, which could be used to effectively distinguish bruised loquats from normal loquats. Then, based on the selected second PC (PC2) score images, a morphological segmentation method (MSM) was proposed to distinguish bruised loquats from normal loquats. Furthermore, the weight coefficients of corresponding wavelength points of different degrees of bruising of loquats were analyzed, and the local extreme points and both sides of the interval were selected as the characteristic wavelength points for multi-spectral image processing. A gray level co-occurrence matrix (GLCM) was used to extract texture features and gray information from two-band ratio images K782/999. Finally, the MAM was proposed to detect the degree of bruising of loquats, which included the spectral data of three characteristic wavelength points in the NIR region coupled with texture features of the two-band ratio images, and the classification accuracy was 91.3%. This study shows that the MAM can be used as an effective dimensionality reduction method. The method not only improves the effect of prediction but also simplifies the process of prediction and ensures the accuracy of classification. The MSM can be used for rapid detection of normal and bruised fruits, and the MAM can be used to classify the degree of bruising of bruised fruits. Consequently, the processed methods are effective and can be used for the rapid and nondestructive detection of the degree of bruising of fruit.

Characterization and functional analysis of a myeloid differentiation factor 88 in Ostrinia furnacalis Guenée larvae infected by Bacillus thuringiensis.

Myeloid differentiation factor 88 (MyD88) is a pivotal adapter protein involved in activating nuclear factor NF-κB of the Toll pathway in insect innate immunity. MyD88 has been extensively studied in vertebrates and Drosophila. However, the information ascribed to MyD88 in Lepidoptera is scarce. In the present study, an Ostrinia furnacalis MyD88 (OfMyD88) cDNA was cloned and functionally characterized (GenBank accession no. MN906311). The complete cDNA sequence of OfMyD88 is 804 bp, and contains a 630 bp open reading frame encoding 209 amino acid residues. OfMyD88 has the death domain (DD), an intermediate domain, and the Toll/interleukin 1 receptor (TIR) domain. OfMyD88 was widely expressed in immune-related tissues such as hemocytes, fat body, midgut, and integument, with the highest expression level in hemocytes, and the lowest expression level in integument. To clarify the immune function of MyD88, O. furnacalis larvae were challenged with Bacillus thuringiensis (Bt) through feeding. Bt oral infection had significantly up-regulated the expression of OfMyD88 and immune genes, including PPO2 (prophenoloxidase 2), Attacin, Gloverin, Cecropin, Moricin, GRP3 (ß-1, 3-Glucan recognition protein 3), and Lysozyme, and increased the activities of PO and lysozyme in hemolymph of O. furnacalis larvae. Knockdown of OfMyD88 by RNA interference suppressed the expression levels of immune related genes, but not PPO2 in the larvae orally infected with Bt, suggesting that OfMyD88 is involved in defending against Bt invasion through the Toll signaling pathway, but does not affect the PPO expression in O. furnacalis larvae.

Transcriptomic analysis provides insights into the immune responses and nutrition in Ostrinia furnacalis larvae parasitized by Macrocentrus cingulum.

Macrocentrus cingulum is a principal endoparasite of Ostrinia furnacalis larvae. M. cingulum larvae repress host immune responses for survival and ingest host nutrients for development until emerging. However, most investigations focused on the mechanisms of how wasps repress the host immunity, the triggered immune responses and nutrient status altered by wasps in host are neglected. In this study, we found that parasitized O. furnacalis larvae activated fast recognition responses and produced some effectors such as lysozyme and antimicrobial peptides, along with more consumption of trehalose, glucose, and even lipid to defend against the invading M. cingulum. However, the expression of peroxidase 6 and superoxide dismutase 2 (SOD 2) was upregulated, and the messenger RNA (mRNA) levels of cellular immunity-related genes such as thioester-containing protein 2 (TEP 2) and hemocytin were also reduced, suggesting that some immune responses were selectively shut down by wasp parasitization. Taken together, all the results indicated that parasitized O. furnacalis larvae selectively activate the immune recognition response, and upregulate effector genes, but suppress ROS reaction and cellular immunity, and invest more energy to fuel certain immune responses to defend against the wasp invading. This study provides useful information for further identifying key components of the nutrition and innate immune repertoire which may shape host-parasitoid coevolutionary dynamics.

Characterization and functional analysis of a Relish gene from the Asian corn borer, Ostrinia furnacalis (Guenée).

Pathogen-induced host immune responses reduce the efficacy of pathogens used to control pests. However, compared to the well-deciphered immunity system of Drosophila melanogaster, the immunity system of agricultural pests is largely unconfirmed through functional analysis. Beginning to unveil mechanisms of transcription regulation of immune genes in the Asian corn borer, Ostrinia furnacalis, we cloned the complementary DNA (cDNA) of a transcription factor Relish by rapid amplification of cDNA ends. The 3164 bp cDNA, designated Of-Relish, encodes a 956-residue protein. Bioinformatic analysis showed that Of-Relish had a Rel homology domain, a predicted cleavage site between Q409 and L410 , six ankyrin repeats, and a death domain. The response of Of-Relish expression to the Gram-negative bacteria Pseudomonas aeruginosa was sooner and stronger than to the Gram-positive Micrococcus luteus. The antimicrobial peptide genes Attacin and Gloverin had similar expression patterns in response to the infections. Knockdown of Of-Relish led to a decrease in Attacin and Gloverin messenger RNA levels, suggesting that Attacin and Gloverin were regulated by Of-Relish. Together, the results suggested that Of-Relish is a key component of the IMD pathway in O. furnacalis, involved in defense against P. aeruginosa through activation of Attacin and Gloverin.

3D printed aluminum flat heat pipes with micro grooves for efficient thermal management of high power LEDs.

As the electronic technology becomes increasingly integrated and miniaturized, thermal management has become a major challenge for electronic device applications. A heat pipe is a highly efficient two-phase heat transfer device. Due to its simple structure, high thermal conductivity and good temperature uniformity, it has been used in many different industrial fields. A novel aluminum flat heat pipe, with micro-grooves, has in the present work been designed and fabricated by using a 3D printing technology. Aluminum powder was used as a raw material, which was selectively melted and solidified to form the shape of the heat pipe. The sintered aluminum powder increased the roughness of the inner surface of the heat pipe, and the designed micro-grooves further enhanced the capillary forces induced by the wick structure. The wettability, for the working fluid (acetone), was excellent and the capillary forces were sufficient for the working fluid to flow back in the pipe. The effects of working fluid filling ratio, on the heat transfer performance of the heat pipe, was also investigated. It was shown that a filling ratio of 10% gave the best heat transfer performance with the lowest thermal resistance. The 3D-printed flat heat pipe was, therefore, also tested for the thermal management of a LED. The temperature of the LED could be kept within 40 °C and its service life became prolonged.

Tell the Device Password: Smart Device Wi-Fi Connection Based on Audio Waves.

IoT devices are now enriching people's life. However, the security of IoT devices seldom attracts manufacturers' attention. There are already some solutions to the problem of connecting a smart device to a user's wireless network based on the 802.11 transmission such as Smart Config from TI. However, it is insecure in many situations, and it does not have a satisfactory transmission speed, which does not mean that it has a low bit rate. It usually takes a long time for the device to recognize the data it receives and decode them. In this paper, we propose a new Wi-Fi connection method based on audio waves. This method is based on MFSK (Multiple frequency-shift keying) and works well in short distance, which enables the correctness and efficiency. In addition, audio waves can hardly be eavesdropped, which provides higher security than other methods. We also put forward an encryption solution by using jamming signal, which can greatly improve the security of the transmission.