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Wnt/β-catenin signaling is a critical pathway that influences development and therapeutic response of non-small cell lung cancer (NSCLC). In recent years, many Wnt regulators, including proteins, miRNAs, lncRNAs, and circRNAs, have been found to promote or inhibit signaling by acting on Wnt proteins, receptors, signal transducers and transcriptional effectors. The identification of these regulators and their underlying molecular mechanisms provides important implications for how to target this pathway therapeutically. In this review, we summarize recent studies of Wnt regulators in the development and therapeutic response of NSCLC. [ABSTRACT FROM AUTHOR]

Dwarf apple is one of the most important forms of garden economy, which has become a new engine for rural revitalization. The effective detection of coloring and ripening apples in complex environments is important for the sustainable development of smart agricultural operations. Addressing the issues of low detection efficiency in the greenhouse and the challenges associated with deploying complex target detection algorithms on low-cost equipment, we propose an enhanced lightweight model rooted in YOLOv7. Firstly, we enhance the model training performance by incorporating the Squeeze-and-Excite attention mechanism, which can enhance feature extraction capability. Then, an SCYLLA-IoU (SIoU) loss function is introduced to improve the ability of extracting occluded objects in complex environments. Finally, the model was simplified by introducing depthwise separable convolution and adding a ghost module after up-sampling layers. The improved YOLOv7 model has the highest AP value, which is 10.00%, 5.61%, and 6.00% higher compared to YOLOv5, YOLOv7, and YOLOX, respectively. The improved YOLOv7 model has an MAP value of 95.65%, which provides higher apple detection accuracy compared to other detection models and is suitable for potted dwarf anvil apple identification and detection. [ABSTRACT FROM AUTHOR]

This study utilized a plant-wearable sap flow sensor developed by a multidisciplinary team at Zhejiang University to monitor water distribution patterns in watermelon fruit stalks throughout their developmental stages. The dynamic rules of sap flow at different stages of fruit development were discovered: (1) In the first stage, sap flow into the fruit gradually halts after sunrise due to increased leaf transpiration, followed by a rapid increase post-noon until the next morning, correlating with fruit expansion. (2) In the second stage, the time of inflow sap from noon to night is significantly shortened, while the outflow sap from fruit is observed with the enhancement of leaf transpiration after sunrise, which is consistent with the slow fruit growth at this stage. (3) In the third stage, the sap flow maintains the diurnal pattern. However, the sap flow that inputs the fruit at night is basically equal to the sap flow that outputs the fruit during the day; the fruit phenotype does not change anymore. In addition, a strong correlation between the daily mass growth in fruit and the daily sap flow amount in fruit stalk was identified, validating the sensor's utility for fruit growth monitoring and yield prediction. [ABSTRACT FROM AUTHOR]

Drought, an intricate natural phenomenon globally, significantly influences the gross primary productivity (GPP) and carbon sink potential of tropical forests. Present research on the drought response primarily focuses on natural forests, such as the Amazon rainforest, with relatively limited studies on tropical plantations. Therefore, for a comprehensive understanding of global climate change, accurately evaluating and analyzing the sensitivity and vulnerability of rubber plantation GPP to various drought characteristics is crucial. The Standardized Precipitation Evapotranspiration Index (SPEI) was used in this research to quantify drought intensity. The Spatially Explicit Individual Based Dynamic Global Vegetation Model (SEIB-DGVM) was localized based on observation data from the Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station. Subsequently, the calibrated model was utilized to simulate the dynamic process of rubber plantation GPP under multi-gradient drought scenarios (2 extreme boundaries × 3 drought initiation seasons × 4 drought intensities × 12 drought durations × 12 SPEI time scales). The results show that the sensitivity and vulnerability of rubber plantation GPP exhibit significant differences under drought scenarios in different initiation seasons; GPP exhibits higher sensitivity to extreme, long-duration flash droughts in the early rainy season. Regarding vulnerability, the impact of extreme, long-duration flash droughts on GPP is most pronounced. This research lays the foundation for estimating the impact of droughts on the GPP of rubber plantations under future climate change scenarios, providing a scientific basis for enhancing regional ecological restoration and protection. [ABSTRACT FROM AUTHOR]

The resistive functional layer in SrFeOx (SFO) topological phase transition (TPT) memristors is typically epitaxially grown on a perovskite bottom electrode and thus the bottom electrode plays an important role in the microstructure and resistive switching performance of the SFO functional layer. Unfortunately, the excessive diffusion of oxygen in the bottom electrode to SrFeOx causes uncontrollable distortion of the microstructure of the resistive functional layer, thereby compromising the overall device properties. In this study, SFO films were epitaxially grown on two different bottom electrodes of La0.7Sr0.3MnO3 (LSMO) and SrRuO3 (SRO) using pulsed laser deposition (PLD). The SFO memristor with a LSMO electrode exhibits excellent cycling stability, ON/OFF ratio, data retention, and endurance performance. In addition, the phase constituents, superlattice-like stripes and elemental valence states of SFO/LSMO and SFO/SRO hetero-structures were characterized by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy, respectively. Furthermore, the oxygen migration free energy barriers of the bottom electrodes in the two devices were calculated by first-principles. All the above research results indicate that the LSMO electrode, being less prone to diffuse oxygen ions, significantly contributes to the superior structural stability and enhanced performance of the SFO/LSMO heterostructure. Finally, the energy band structures and Schottky barriers between BM-SFO and the top electrode of Au and the bottom electrode of LSMO were analyzed by ultraviolet photoelectron spectroscopy and ultraviolet-visible spectroscopy, which provide experimental insights into explaining its conductive mechanism. [ABSTRACT FROM AUTHOR]

The stability of W–C compounds (WC)-type ReC has been controversial for many years. Here, based on ab initio algorithm, we systematically searched for stable structures in the rhenium–carbon (Re–C) system at 0–300 gigapascal (GPa) pressure and analyzed the phase diagram within the pressure range. Only P63/mmc-Re2C, C2/m-Re3C, P21/m-Re4C, and C2/m-Re5C2 phases are found to be stable under 0–300 GPa, while WC-type ReC has high enthalpy and does not appear in the phase diagram. We also discussed the stability of WC-type ReC. Among these structures, C2/m-Re3C, P21/m-Re4C, and C2/m-Re5C2 are hitherto unknown structures, which could maintain dynamic and mechanical stability under ambient pressure. In addition, through the analysis of the structural and mechanical properties, P63/mmc-Re2C is the hardest metal among them with 31.5 GPa Vickers hardness at 0 GPa, and the metastable P 6 ¯ m 2 -Re5C3 has the second-highest hardness (29.3 GPa), both of which exceed the hardness of TiN (18.7 GPa), the commercial material used for cutting tools. The study of Re–C compounds with high hardness provides theoretical guidance for further experimental research. [ABSTRACT FROM AUTHOR]

Recent advances in speaker embeddings promote a great development of speaker diarization. However, determining 'who spoke when' in the meeting scenarios is still challenging due to similar speaker voices and unknown speaker quantity. In this paper, this research proposes enhanced discriminative features for speaker diarization, including discriminative speaker-specific features based on Siamese networks, and a speaker re-verification method. With Siamese architecture, SiamTDNN, this research first explores latent representations which is capable of modeling intra-class and inter-class differences between speakers, by training with audio pairs. Then, the re-verification method is introduced with a local-global strategy to identify speakers in a multi-person talking scene. Our method provides a novel speaker embedding with enhanced discriminative power for disambiguated speakers and achieves an elevated upper bound on the number of speakers. The proposed speaker embedding achieved an EER of 1.1% and a minDCF of 0.1192 on VoxCeleb1 for the speaker verification task. Extensive experiments on AiShell-4, ICSI, AMI and VoxConverse demonstrate the effectiveness of the proposed method with an average DER reduction of 3% and an RTF of 0.0792. [ABSTRACT FROM AUTHOR]

Topological phase transition materials have strong coupling between their charge, spin orbitals, and lattice structure, which makes them have good electrical and magnetic properties, leading to promising applications in the fields of memristive devices. The smaller Gibbs free energy difference between the topological phases, the stable oxygen vacancy ordered structure, and the reversible topological phase transition promote the memristive effect, which is more conducive to its application in information storage, information processing, information calculation, and other related fields. In particular, extracting the current resistance or conductance of the two-terminal memristor to convert to the weight of the synapse in the neural network can simulate the behavior of biological synapses in their structure and function. In addition, in order to improve the performance of memristors and better apply them to neuromorphic computing, methods such as ion doping, electrode selection, interface modulation, and preparation process control have been demonstrated in memristors based on topological phase transition materials. At present, it is considered an effective method to obtain a unique resistive switching behavior by improving the process of preparing functional layers, regulating the crystal phase of topological phase transition materials, and constructing interface barrier-dependent devices. In this review, we systematically expound the resistance switching mechanism, resistance switching performance regulation, and neuromorphic computing of topological phase transition memristors, and provide some suggestions for the challenges faced by the development of the next generation of non-volatile memory and brain-like neuromorphic devices based on topological phase transition materials. [ABSTRACT FROM AUTHOR]

An ideal catalyst should have a relative hydrogen adsorption Gibbs free energy (ΔGH) close to zero [J. K. Nørskov, et al., J. Electrochem. Soc., 2005, 152, J23]. However, most of the known catalysts cannot reach this standard. Based on first-principles calculations, we studied the hydrogen evolution reaction (HER) catalytic performance of pristine and defect (including vacancy and heteroatom doping) structures in terms of its ΔGH. We found that the ΔGH values of Co-doped HfS2 and P-doped HfSe2 are extremely close to zero, even closer than that of Pt (111), indicating that they are excellent catalysts. Moreover, we found that the source of the HER catalytic performance of Co-doped HfS2 is the reduction of electron accumulation of the active site S atom. Our work provides two potential ideal catalysts and provides guidance for the experimental group to search for suitable catalysts. [ABSTRACT FROM AUTHOR]

In China, an effective form of agricultural organization called an agri-industrialized union (AIU) has been on the rise and is recognized as making a great contribution to rural revitalization. However, individual AIUs appear to be conducted in different ways during their development. Some are successfully operated by active members in cohesive combinations, while some fail because of disconnection and instability. The purpose of this study is to encourage all members to take initiative and to act cooperatively to ensure high-quality resource usage in AIUs. Based on the theory of planned behavior (TPB) and the theory of perceived value, a structural equation model was used to examine the main factors affecting members' willingness to cooperate in AIUs in Hebei Province. The data collected from a survey of 247 AIUs indicated that behavioral attitudes and subjective norms have a direct impact on cooperative initiatives. Perceived behavioral control indirectly affects cooperative initiatives. Perceived management ability influences subjective norms, while perceived interest–risk influences behavioral attitudes and perceived behavioral control, especially in hierarchical governance groups. The influences of behavioral attitudes, perceived behavioral control, and subjective norms are stronger in mixed-governance groups. The results of this research can provide recommendations for policymaking that may help to ensure the stable development of AIUs and rural development. [ABSTRACT FROM AUTHOR]

BiFeO3 is the only material with ferroelectric Curie temperature and Néel temperature higher than room temperature, making it one of the most well-studied multiferroic materials. Based on an ab initio evolutionary algorithm, we predicted a new cubic C-type antiferromagnetic structure (Fd3¯m-BiFeO3) at ambient pressure. It was found that Fd3¯m-BiFeO3 is the hardest BiFeO3 (Vickers hardness ∼ 9.12 GPa), about 78% harder than R3c-BiFeO3 (the well-known multiferroic material), which contributes to extending the life of BiFeO3 devices. In addition, Fd3¯m-BiFeO3 has the largest shear modulus (83.74 GPa) and the largest Young's modulus (214.72 GPa). Besides, we found an interesting phenomenon that among the common multiferroic materials (BiFeO3, BaTiO3, PbTiO3, SrRuO3, KNbO3, and BiMnO3), Pnma-BiMnO3 has the largest bulk modulus, and its bulk modulus is about 15% larger than that of Fd3¯m-BiFeO3. However, its Vickers hardness (4.47 GPa) is much smaller than that of Fd3¯m-BiFeO3. This is because the Vickers hardness is proportional to the shear modulus and the shear modulus of Fd3¯m-BiFeO3 is larger than that of Pnma-BiMnO3. This work provides a deeper and more comprehensive understanding of BiFeO3. [ABSTRACT FROM AUTHOR]

Solar cell is a kind of devices for renewable and environmentally friendly energy conversion. One of the important things for solar cells is conversion efficiency. While much attention has been drawn to improving efficiency, the role of strain engineering in two-dimensional materials is not yet well-understood. Here, we propose a Pmc 21-As monolayer that can be used as a solar cell absorbing material. The bandgap of single-layer Pmc 21-As can be tuned from 1.83 to 0 eV by applying tensile strain, while keeping the direct bandgap characteristic. Moreover, it has high light absorption efficiency in the visible and near-infrared regions, which demonstrates a great advantage for improving the conversion efficiency of solar cells. Based on the tunable electronic and optical properties, a novel design strategy for solar cells with a wide absorption range and high absorption efficiency is suggested. Our results not only have direct implication in strain effect on two-dimensional materials, but also give a possible concept for improving the solar cell performance. [ABSTRACT FROM AUTHOR]

Visual tracking is an important area in computer vision. Based on the Siamese network, current tracking methods employ the self‐attention block in convolutional networks to extract semantic features containing the image structure information of an object. However, spatial continuity is a point of contradiction between two seemingly unrelated challenges, that is, occlusion and similar distractor, in tracking methods. At the same time, it is a spatially discontinuous task to locate a target reappearing after occlusion accurately. The prediction of bounding boxes should be constrained by spatial continuity to prevent them from jumping into similar distractors. This study proposes a novel tracking method for introducing spatial continuity in visual tracking called M‐CoTransT; the novel tracking method is developed through the confidence‐based adaptive Markov motion model (M‐model) and a novel correlation‐based feature fusion network (CoTransT). In particular, the M‐model provides confidence for the nodes of the Markov motion model to estimate the motion state continuity. It also predicts a more accurate search region for CoTransT, which then adds a cross‐correlation branch into the self‐attention tracking network to enhance the continuity of target appearance in the feature space. Extensive experiments on five challenging datasets (LaSOT, GOT‐10k, TrackingNet, OTB‐2015 and UAV123) demonstrated the effectiveness of the proposed M‐CoTransT in visual tracking. [ABSTRACT FROM AUTHOR]

BiFeO3 is one of the most widely studied multiferroic materials, because of its large spontaneous polarization at room temperature, as well as ferroelasticity and antiferromagnetism. Using an ab initio evolutionary algorithm, we found two new dynamically stable BiFeO3 structures (P63 and P6322) at ambient pressure. Their energy is only 0.0662 and 0.0659 eV per atom higher than the famous R3c–BiFeO3, and they have large spontaneous polarization, i.e., 71.82 μC cm−2 and 86.06 μC cm−2, respectively. The spontaneous polarization is caused by the movement of the Bi3+ atom along the [001] direction and mainly comes from the 6s electron of Bi3+. Interestingly, there is no lone pair electron of Bi3+, which is different from R3c–BiFeO3. The new structures have the same magnetic configurations as R3c–BiFeO3 (G-type antiferromagnetism), but they are characterized by one-dimensional channels linked by a group of two via surface-sharing oxygen octahedra. Due to the similarity of the two structures, both of them have indirect bandgap structures, and the bandgaps are 2.62 eV and 2.60 eV, respectively. This work not only broadens the structural diversity of BiFeO3 but also has constructive significance for the study of spontaneous polarization of new structures of multiferroic materials. [ABSTRACT FROM AUTHOR]

Visual object tracking is an important topic in computer vision, which has successfully utilized pretrained convolutional neural networks, such as VGG and ResNet. However, the features extracted by these pretrained models are high dimensional, and the redundant feature channels reduce target localization and scale estimation precision, leading to tracking drifting. In this paper, a novel visual object tracking method, called learning enhanced feature responses tracking (LEFRT), is proposed, which adopts the target-specific features to enhance target localization and scale estimation responses. First, a channel attention module, called target-specific network (TSNet), is presented to reduce the redundant feature channels. Secondly, the scale estimation network (SCENet) is introduced to extract spatial structural features to generate a more precise response for the scale estimation. Extensive experiments on six tracking benchmarks, including LaSOT, GOT-10k, TrackingNet, OTB-2013, OTB-2015, and TC-128, demonstrate that the proposed algorithm can effectively improve the precision and speed of visual object tracking. LEFRT achieves 90.4% precision and a 71.2% success rate on the OTB-2015 dataset, improving the tracking methods based on the pretrained features. [ABSTRACT FROM AUTHOR]

BACKGROUND: The COVID‐19 outbreak caused short‐term disruptions in the supply chain of fresh agricultural products (FAPs), which exposed the vulnerability of the existing FAP supply chain. With pandemic control being widely coordinated, the supply chain of FAPs was gradually optimized and improved. However, after the outbreak of COVID‐19, achieving an effective supply of FAPs in future pandemics has become a key issue. The present work therefore aimed to construct a three‐level supply chain based on the Stackelberg game model, consisting of suppliers, third‐party logistics (TPL), and retailers, to guarantee the supply of FAPs. COVID‐19 pandemic factors such as virus infection coefficients and pandemic prevention efforts were fully integrated into the model. RESULTS: Compared with the wholesale prices of FAPs, preservation efforts and pandemic prevention efforts have huge impacts on the retail prices of FAPs. When suppliers are in the leading position, the quality assurance effort level is positively correlated with the optimal profit. Compared with this situation, when FAP retailers are in the leading position, TPL providers show higher levels of pandemic prevention effort and FAP preservation effort. With an increase in consumer preference for pandemic prevention, the profits of supply‐chain members when FAP retailers are in the leading position will gradually increase. CONCLUSION: This study reveals an effective supply mechanism for FAPs in metropolitan areas during the COVID‐19 pandemic and describes the authors' experience of guaranteeing the quality and safety of FAPs for future pandemic cases. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Hydrogenation of palm oil over commercial NiMo/γ-Al 2 O 3 catalysts and the effect of operating conditions were investigated in an autoclave with a continuous H 2 flow mode. Methanation as the side reactions were taken into account in the reaction path selectivity for the first time. Three competing reaction pathways of hydrodecarboxylation, hydrocarbonation, and direct hydrodeoxygenation were clearly distinguished by quantifying the oxygen in the aqueous, organic, and gas phases. The results corroborated that the temperature and hydrogen supply were crucial to oxygen removal and the selectivity of the HDO pathways. Methane is the predominant gas product rather than propane during triglyceride deoxygenation, in which 87–100% of the methane production comes from the glycerol skeleton of the triglyceride and the rest comes from the CO methanation. Lower temperature favored the direct HDO route, while the selectivity of the HDCO and HDCO2 reactions preferred a higher temperature. HDO dominated the hydrodeoxygenation process under all H 2 supply conditions, followed by the HDCO2 pathway and the HDCO reaction. This study brings the understanding of the vegetable oil triglyceride hydrodeoxygenation process to the molecular level and can potentially guide the optimization of process conditions. [Display omitted] • Methane is the predominant gas product rather than propane during triglyceride deoxygenation. • Selectivity of hydrodecarboxylation and hydrodecarbonylation is distinguished by oxygen quantification. • Larger H 2 supply and lower temperature favor the direct HDO, HDCO2 is the opposite. • HDCO reaction is the least sensitive to temperature and H 2 supply among three HDO pathways. [ABSTRACT FROM AUTHOR]