Abstract
This work aims to address the heat accumulation issue in electronic components during high‐frequency operation through the preparation of novel thermally conductive composites. First, ...polydopamine (PDA) and in‐situ growth of silver (Ag) nanoparticles are applied for the surface modification of graphene oxide (GO) and carbon nanotube (CNT) to prepare pGO@Ag and pCNT@Ag hybrid filler, respectively. Then, nitrile butadiene rubber (NBR) is chosen as the polymeric matrix and simultaneously incorporated with both pGO@Ag and pCNT@Ag to prepare polymeric composites with excellent thermal conductivity (TC) and dielectric constant (
ɛ
r
). Due to the construction of 3D heat conduction networks by utilizing 2D pGO@Ag and 1D pCNT@Ag, the fabricated NBR composites achieved the maximum TC of 1.0112 W/(mK), which is 636% higher than that of neat NBR (0.1373 W (mK)
−1
). At the filler loading of 9 vol%, the TC of pGO@Ag/pCNT@Ag/NBR composite is 152% that of GO/CNT/NBR composite (0.6660 W (mK)
−1
). Moreover, due to electron polarization effect of GO and CNT and micro‐capacitor effect of Ag nanoparticles, a large
ɛ
r
of 147.12 is attained at 10 Hz for NBR composites. Overall, the development of dielectric polymer materials with high TC is beneficial for enhancing the service life and safety stability of the electronic components.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
MdMYB1 acts as a crucial component of the MYB‐bHLH‐WD40 complex to regulate anthocyanin biosynthesis in red‐skinned apples (Malus domestica), but little is known about its post‐translational ...regulation. Here, a small ubiquitin‐like modifier E3 ligase MdSIZ1 was screened out as an MdMYB1‐interacting protein with a yeast two‐hybridization approach. The interaction between MdSIZ1 and MdMYB1 was further verified with pull‐down and CoIP assays. Furthermore, it was found that MdSIZ1 directly sumoylated MdMYB1 proteins in vivo and in vitro, especially under moderately low temperature (17 °C) conditions, and that this sumoylation was required for MdMYB1 protein stability. Moreover, the transcription level of MdSIZ1 gene was remarkably induced by low temperature and phosphorus deficiency, and MdSIZ1 overexpression exerted a large positive influence on anthocyanin accumulation and red fruit coloration, suggesting its important role in the regulation of anthocyanin biosynthesis under stress conditions. Our findings reveal an important role for a small ubiquitin‐like modifier modification of MYB transcription factors in regulation of anthocyanin biosynthesis in plants.
Anthocyanin biosynthesis is influenced by environmental factors in plants; however, the mechanism underlying this process remains poorly understood. Here, we found that the small ubiquitin‐like modifier E3 ligase MdSIZ1 directly interacted with and sumoylated MdMYB1 to promote its protein stability under low‐temperature conditions, resulting in anthocyanin accumulation. This study provides new insight into the post‐translational modification of MdMYB1 under low‐temperature treatment and the function of the MdSIZ1‐mediated sumoylation in regulating anthocyanin biosynthesis.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Electroporation based locally enhanced electric field treatment (LEEFT) is an emerging bacteria inactivation technology for drinking water disinfection. Nevertheless, the lethal electroporation ...threshold (LET) for bacteria has not been studied, partly due to the tedious work required by traditional experimental methods. Here, a lab-on-a-chip device composed of platinum electrodes deposited on a glass substrate is developed for rapid determination of the LET. When voltage pulses are applied, an electric field with a linear strength gradient is generated on a channel between the electrodes. Bacterial cells exposed to the electric field stronger than the LET are inactivated, while others remain intact. After a cell staining process to differentiate dead and live bacterial cells, the LETs are obtained by analyzing the fluorescence microscopy images. Staphylococcus epidermidis has been utilized as a model bacterium in this study. The LETs range from 10 kV/cm to 35 kV/cm under different pulsed electric field conditions, decreasing with the increase of pulse width, effective treatment time, and pulsed electric field frequency. The effects of medium properties on the LET were also investigated. This lab-on-a-chip device and the experimental approach can also be used to determine the LETs for other microorganisms found in drinking water.
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•A platform was developed for lethal electroporation threshold (LET) determination.•The LETs of Staphylococcus epidermidis were determined to be between 10 and 35 kV/cm.•The LET decreases with the increase of effective time, pulse width, and frequency.•The effects of different medium properties on LET were investigated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•A self-centering variable damping energy dissipation (SC-VDED) brace is proposed.•A series of cyclic tests of a large-scale SC-VDED brace specimen were carried out.•Brace exhibits quasi-flag-shaped ...hysteretic responses with large energy dissipation.•Fatigue and destructive tests demonstrate that brace has stable seismic behaviors.
A new self-centering variable damping energy dissipation (SC–VDED) brace is proposed to reduce the activation force and sudden change in stiffness after activation of self-centering energy dissipation braces. The brace uses the combination disc springs to provide self-centering capability and the structural design of a magnetorheological (MR) fluid device to realize variable damping energy dissipation. The mechanics of the SC–VDED brace and the equations governing its design and hysteretic responses are presented. A brace specimen with a total length of 1.365 m was designed and fabricated, and a series of cyclic tests were carried out under the sinusoidal excitation with different frequencies and amplitudes. Results demonstrate that the brace exhibits full quasi-flag-shaped hysteretic responses, a small activation force, few sudden change in stiffness, and large energy dissipation. The pre-pressed force of the combination disc springs should be larger than the initial damping force, and their stiffness should be increased to give full play to the self-centering and energy dissipation capabilities of the brace. Fatigue and destructive test results indicate that the behaviors of the brace are stable enough to provide self-centering and energy dissipation capabilities, and the loose and severe stress concentration of the outer tube clamps cause the brace to fail.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
With the boom of social media, it is a very popular trend for people to share what they are doing with friends across various social networking platforms. Nowadays, we have a vast amount of ...descriptions, comments, and ratings for local services. The information is valuable for new users to judge whether the services meet their requirements before partaking. In this paper, we propose a user-service rating prediction approach by exploring social users' rating behaviors. In order to predict user-service ratings, we focus on users' rating behaviors. In our opinion, the rating behavior in recommender system could be embodied in these aspects: 1) when user rated the item, 2) what the rating is, 3) what the item is, 4) what the user interest that we could dig from his/her rating records is, and 5) how the user's rating behavior diffuses among his/her social friends. Therefore, we propose a concept of the rating schedule to represent users' daily rating behaviors. In addition, we propose the factor of interpersonal rating behavior diffusion to deep understand users' rating behaviors. In the proposed user-service rating prediction approach, we fuse four factors-user personal interest (related to user and the item's topics), interpersonal interest similarity (related to user interest), interpersonal rating behavior similarity (related to users' rating behavior habits), and interpersonal rating behavior diffusion (related to users' behavior diffusions)-into a unified matrix-factorized framework. We conduct a series of experiments in the Yelp dataset and Douban Movie dataset. Experimental results show the effectiveness of our approach.
Background Deep learning has presented considerable potential and is gaining more importance in computer assisted diagnosis. As the gold standard for pathologically diagnosing cervical ...intraepithelial lesions and invasive cervical cancer, colposcopy-guided biopsy faces challenges in improving accuracy and efficiency worldwide, especially in developing countries. To ease the heavy burden of cervical cancer screening, it is urgent to establish a scientific, accurate and efficient method for assisting diagnosis and biopsy. Methods The data were collected to establish three deep-learning-based models. For every case, one saline image, one acetic image, one iodine image and the corresponding clinical information, including age, the results of human papillomavirus testing and cytology, type of transformation zone, and pathologic diagnosis, were collected. The dataset was proportionally divided into three subsets including the training set, the test set and the validation set, at a ratio of 8:1:1. The validation set was used to evaluate model performance. After model establishment, an independent dataset of high-definition images was collected to further evaluate the model performance. In addition, the comparison of diagnostic accuracy between colposcopists and models weas performed. Results The sensitivity, specificity and accuracy of the classification model to differentiate negative cases from positive cases were 85.38%, 82.62% and 84.10% respectively, with an AUC of 0.93. The recall and DICE of the segmentation model to segment suspicious lesions in acetic images were 84.73% and 61.64%, with an average accuracy of 95.59%. Furthermore, 84.67% of high-grade lesions were detected by the acetic detection model. Compared to colposcopists, the diagnostic system performed better in ordinary colposcopy images but slightly unsatisfactory in high-definition images. Implications The deep learning-based diagnostic system could help assist colposcopy diagnosis and biopsy for HSILs.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Creep behavior of loess-like soil is closely related to microstructural changes. The microstructure of loess-like soil collected from the Xi'an area, China, was investigated using triaxial creep ...tests. Qualitative microstructural observations were made by examining vertical and transverse sections from the undisturbed and tested samples with a polarizing microscope. Quantitative data were acquired by image analysis of SEM images of those sections. The image analysis documented changes in particles and pore structure under different axial stress and confining pressures. The results show that: (1) Undisturbed samples have plank-macrospore cline-cementation structure with the particles distributed randomly. The number and area of four kinds of pores decrease in the decay creep stage. The orientation of particle long-axis gradually aligns (weakly) in the steady creep stage. The samples have a lightly cemented mosaic microporous structure and plastic minerals like illite significantly aligned in a preferred orientation, and rigid quartz and feldspar grains become slightly arranged along the illite preferred direction in accelerated creep stage. The orientation of particles and pores interconnections eventually result in the creep failure of sample. (2) The prefer orientations of pores are most significant in accelerated creep stage, and the pores have insignificant preferred orientation in creep failure stage. (3) Mesopores cover the largest area, and they are the most important factors leading to loess-like soil creep. Undisturbed samples contain the largest number of pores which cover the largest area among all of the samples. As creep progresses, both number and area decrease gradually before accelerated creep stage, and finally the pore area has its largest in creep failure stage. (4) The pores in these samples are relatively oblate in shape with rough outlines in undisturbed samples, and the greater the deviatory stress is, the slender the pores with smoother outlines will be.
•Creep behavior of loess-like soil is closely related to microstructural changes.•The microstructure of loess-like soil was investigated by SEM.•The image analysis documented changes in particles and micropore structure during triaxial creep tests.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Graph neural network (GNN) is effective in modeling high-order interactions and has been widely used in various personalized applications such as recommendation. However, mainstream personalization ...methods rely on centralized GNN learning on global graphs, which have considerable privacy risks due to the privacy-sensitive nature of user data. Here, we present a federated GNN framework named FedPerGNN for both effective and privacy-preserving personalization. Through a privacy-preserving model update method, we can collaboratively train GNN models based on decentralized graphs inferred from local data. To further exploit graph information beyond local interactions, we introduce a privacy-preserving graph expansion protocol to incorporate high-order information under privacy protection. Experimental results on six datasets for personalization in different scenarios show that FedPerGNN achieves 4.0% ~ 9.6% lower errors than the state-of-the-art federated personalization methods under good privacy protection. FedPerGNN provides a promising direction to mining decentralized graph data in a privacy-preserving manner for responsible and intelligent personalization.
ABSTRACT
Low environmental temperatures promote anthocyanin accumulation and fruit colouration by up‐regulating the expression of genes involved in anthocyanin biosynthesis and regulation in many ...fruit trees. However, the molecular mechanism by which fruit trees regulate this process in response to low temperature (LT) remains largely unknown. In this study, the cold‐induced bHLH transcription factor gene MdbHLH3 was isolated from an apple tree and was found to interact physically and specifically through two regions (amino acids 1–23 and 186–228) at the N terminus with the MYB partner MdMYB1 (allelic to MdMYB10). Subsequently, MdbHLH3 bound to the promoters of the anthocyanin biosynthesis genes MdDFR and MdUFGT and the regulatory gene MdMYB1 to activate their expression. Furthermore, the MdbHLH3 protein was post‐translationally modified, possibly involving phosphorylation following exposure to LTs, which enhanced its promoter‐binding capacity and transcription activity. Our results demonstrate the molecular mechanism by which MdbHLH3 regulates LT‐induced anthocyanin accumulation and fruit colouration in apple.
The molecular mechanism by which fruit trees regulate fruit coloration in response to low temperature remains largely unknown. In this study, it was found that the apple transcription factor MdbHLH3 is regulated at transcriptional, translational and posttranlational levels by low temperature, and therefore involved in the modulation of temperature‐controlled anthocyanin biosynthesis and fruit coloration in apple.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
As the overuse of chemicals in our disinfection processes becomes an ever-growing concern, alternative approaches to reduce and replace the usage of chemicals is warranted. Electric field treatment ...has shown promising potential to have synergistic effects with standard chemical-based methods as they both target the cell membrane specifically. In this study, we use a lab-on-a-chip device to understand, observe, and quantify the synergistic effect between electric field treatment and copper inactivation. Observations in situ, and at a single cell level, ensure us that the combined approach has an enhancement effect leading more bacteria to be weakened by electric field treatment and susceptible to inactivation by copper ion permeation. The synergistic effects of electric field treatment and copper can be visually concluded here, enabling the further study of this technology to optimally develop, mature, and scale for its various applications in the future.
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