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The accurate simulation of insulated gate bipolar transistor (IGBT) characteristics is an essential task to predict its electrical behaviors. Numerous physics-based IGBT models have been developed and proven to produce satisfactory simulation results. However, unavailability of device parameters is the key roadblock to the application of these physics-based models. In addition, the coupling between device parameters renders parameter extraction very challenging and heavy. In this article, a novel parameter extraction scheme by switching feature partitioning is proposed, which considerably relaxes the negative impact of parameter coupling during parameter extraction. The IGBT inductive turn-off process and static characteristics are divided into nine typical feature segments under an inductive load. Then, the physical principle of each feature segment is analyzed, and the corresponding influencing parameters of each feature segment are found. During the parameter extraction, the corresponding weights are assigned to the parameter search according to the error of each feature segment. The proposed method for parameter extraction is elaborated. Using the extracted parameters, the simulation results by the physics-based IGBT model are in excellent agreement with the experimental results of the tested IGBT, and the effectiveness of the proposed parameter extraction program is verified. Finally, the extracted parameters are evaluated and verified by global sensitivity analysis.

Monocular face reconstruction is a significant task in many multimedia applications. However, learning-based methods unequivocally suffer from the lack of large datasets annotated with 3-D ground truth. To tackle this problem, we proposed a novel end-to-end 3-D face reconstruction network consisting of a domain-transfer conditional GAN (cGAN) and a face reconstruction network. Our method first uses cGAN to translate the realistic face images to the specific rendered style, with a novel 2-D facial edge consistency loss function to exploit in-the-wild images. The domain-transferred images are then fed into a 3-D face reconstruction network. We further propose a novel reprojection consistency loss to restrict the 3-D face reconstruction network in a self-supervised way. Our approach can be trained with the annotated dataset, synthetic dataset, and in-the-wild images to learn a unified face model. Extensive experiments have demonstrated the effectiveness of our method.

Learning-based face reconstruction methods have recently shown promising performance in recovering face geometry from a single image. However, the lack of training data with 3D annotations severely limits the performance. To tackle this problem, we proposed a novel end-to-end 3D face reconstruction network consisting of a conditional GAN (cGAN) for cross-domain face synthesis and a novel mesh transformer for face reconstruction. Our method first uses cGAN to translate the realistic face images to the specific rendered style, with a 2D facial edge consistency loss function. The domain-transferred images are then fed into face reconstruction network which uses a novel mesh transformer to output 3D mesh vertices. To exploit the domain-transferred in-the-wild images, we further propose a reprojection consistency loss to restrict face reconstruction network in a self-supervised way. Our approach can be trained with annotated dataset, synthetic dataset and in-the-wild images to learn a unified face model. Extensive experiments have demonstrated the effectiveness of our method.

NIR-II FI has emerged as a promising imaging tool for in vivoprecise diagnosis and visualization towards various diseases, ascribed to its merits of attenuated light scattering and tissue absorption and ignorable auto-fluorescence. Owing to its superiority in high specificity, low toxicity, and ignorable invasiveness, photothermal therapy (PTT) has developed as one of the most potential treatment methods for cancer treatment. Although organic optical agents with a donor–acceptor–donor (D–A–D) skeleton have been extensively applied to NIR-II FI and PTT, most were based on the three weak electron acceptors benzobisthiadiazole (BBTD), diketopyrrolopyrrole (DPP), and thiadiazoloquinoxaline (TTQ). Although the acceptor TTQ has developed as a promising acceptor to synthesize molecules for high-resolution NIR-II FI and PTT, reviews focused on TTQ based NIR-II organic molecules for NIR-II FI and PTT were still rarely reported. Hence, this review systemically summarized the current advanced process of TTQ based D–A–D type organic molecules for NIR-II FI and PTT. Firstly, some examples for NIR-II FI of tissue and immune and thrombosis NIR-II FI were presented in detail. Some examples of NIR-II FI-navigated PTT or combination therapy were discussed. Finally, some pending challenges in applying them to NIR-II FI and PTT are discussed.

Frost heave experiments on saturated sandstone and tuff with an open crack are conducted under uniform and unidirectional freezing conditions. Frost heave of crack in sandstone with high permeability is more significant under uniform freezing condition than that under unidirectional freezing condition. However, frost heave of crack in tuff with low permeability is more significant under unidirectional freezing condition. To illustrate the reasons for this phenomenon, a numerical model on the freezing processes of saturated rock with an open crack considering the latent heat of pore water and water in crack is proposed and confirmed to be reliable. Numerical results show that a frozen shell that blocks the migration of water in crack to rock develops first in the outer part of the rock before the freezing of water in crack under uniform freezing condition. However, the migration path of water in crack to the unfrozen rock under freezing front exists under unidirectional freezing condition. The freezing process and permeability of rock together determine the migration of water in crack and lead to the different frost heave modes of crack for various permeable rocks under different freezing conditions. The frost heave modes of crack in rock with low or high permeability are similar under uniform freezing condition because water migration is blocked by a frozen shell and is irrelevant to rock permeability. For high permeability rock, the frost heave of crack will be weakened due to water migration under unidirectional freezing condition; however, the frost heave of crack would be more significant for low permeability rock because water migration is blocked under unidirectional freezing condition. Therefore, the freezing condition and rock permeability determine the frost heave of rock with crack together, and this should be concerned in cold regions engineering applications.

Sulfur-substituted dicyanomethylene-4H-chromene (DCM) derivatives based on the intramolecular charge transfer (ICT) mechanism were designed as near-infrared (NIR) fluorescent dyes. Using the Knoevenagel condensation method, the S-DCM-OH(835)fluorescence dye was synthesized, which had an emission wavelength exceeding 800 nm and 220 nm of a Stokes shift. Compared to commercial ICG, S-DCM-OH(835)was not only synchronized in emission wavelength but also far superior in Stokes shifts. These advantages made the design of S-DCM-NIR(835)based on this dye potentially valuable for biological applications. Based on this chemical structure, a fluorescent S-DCM-NIR(835)nanoprobe with a mean diameter of 17.69 nm was fabricated as the NIR imaging nanoprobe. Results showed that the nanoprobe maintained the high-specificity identification of cysteine (Cys) via the Michael addition reaction, with the detection limitation of 0.11 μM endogenous Cys. More importantly, in an ischemic stroke mouse model, the S-DCM-NIR(835)nanoprobe could monitor the Cys concentration change at stroke lesion due to the disruption of Cys metabolism under the ischemic stroke condition. Such a S-DCM-NIR(835)nanoprobe could not only differentiate the severity of the ischemic stroke using response time but also quantify the concentration of Cys in real-time in vivo.

NIR‐II fluorescence imaging (NIR‐II FI) and photothermal therapy (PTT) have received broad attentions in precise tumor diagnosis and effective treatment attributed to high‐resolution and deep tissue imaging, negligible invasivity, and high‐efficiency treatment. Although many fluorescent molecules have been designed and conducted for NIR‐II FI and PTT, it is still an enormous challenge for researchers to pioneer some rational design guidelines to improve fluorescence brightness. Organic D–A‐type molecules, including small molecules and conjugated polymers, can be designed and developed to improve fluorescence brightness due to their tunable and easy functionalized chemical structures, allowing molecules tailored photophysical properties. In this review, some approaches to the development and design strategies of D–A type small molecules and conjugated polymers for the enhancement of fluorescence brightness are systemically introduced. Meanwhile, some applications of PTT and PTT‐based combination therapy (such as PDT, chemotherapy, or gas therapy) assisted by NIR‐II FI‐based single or multiimaging technologies are classified and represented in detail as well. Finally, the current issues and challenges of NIR‐II organic molecules in NIR‐II FI‐navigated PTT are summarized and discussed, which gives some guidelines for the future development direction of NIR‐II organic molecules for NIR‐II FI‐navigated PTT. In this review, some approaches to the development and design strategies of D–A type small molecules and conjugated polymers for the enhancement of fluorescence brightness are systemically introduced. Meanwhile, some applications of photothermal therpy (PTT) and PTT‐based combination therapies assisted by NIR‐II FI‐based single or multiimaging technologies are classified and represented in detail. Finally, the current issues and challenges of NIR‐II organic molecules in NIR‐II FI‐navigated PTT are summarized and discussed.

Photothermal Therapy In article 2201158by Peng Wang, Pengfei Sun, Min Ji, and co‐workers, some approaches to the development and design strategies of D–A type small molecules and conjugated polymers for the enhancement of fluorescence brightness are systemically introduced. Meanwhile, some applications of photothermal therpy (PTT) and PTT‐based combination therapies assisted by NIR‐II FI‐based single or multiimaging technologies are classified and represented in detail. Finally, the current issues and challenges of NIR‐II organic molecules in NIR‐II FI‐navigated PTT are summarized and discussed.

Along with the exponential growth of high-performance mobile devices, on-device Mobile Landmark Recognition (MLR) has recently attracted increasing research attention. However, the latency and accuracy of automatic recognition remain as bottlenecks against its real-world usage. In this article, we introduce a novel framework that combines interactive image segmentation with multifeature fusion to achieve improved MLR with high accuracy. First, we propose an effective vector binarization method to reduce the memory usage of image descriptors extracted on-device, which maintains comparable recognition accuracy to the original descriptors. Second, we design a location-aware fusion algorithm that can fuse multiple visual features into a compact yet discriminative image descriptor to improve on-device efficiency. Third, a user-friendly interaction scheme is developed that enables interactive foreground/background segmentation to largely improve recognition accuracy. Experimental results demonstrate the effectiveness of the proposed algorithms for on-device MLR applications.

Thymidine glycol (Tg), which is also known as 5,6-dihydroxy-5,6-dihydrothymidine, and 8-oxo-7,8-dihydro-2‘-deoxyguanosine (8-oxodG) are two major types of DNA damage products induced by reactive oxygen species (ROS). Here, we report the synthesis of oligodeoxyribonucleotides (ODNs) containing both Tg and 8-oxodG. The dual incorporation of the two single-base lesions was achieved by using a phosphoramidite building block of 8-oxodG with ultramild base protecting group and a building block of Tg whose nucleobase hydroxyl groups were protected with acetyl functionality. The availability of ODNs carrying neighboring 8-oxodG and Tg provided authentic substrates for assessing the formation and examining the replication and repair of this kind of tandem lesions. In addition, thermodynamic parameters derived from melting temperature data revealed that tandem lesions destabilized the double helix to a greater extent than either of the two single-base lesions alone. The thermodynamic results could offer a basis for understanding the repair of the tandem base lesions.

Reactive oxygen species (ROS) can be induced by both endogenous and exogenous processes, and they can damage biological molecules including nucleic acids. It was shown that X- or -ray irradiation of aqueous solutions of DNA, during which •OH is one of the major ROS, can lead to the formation of intrastrand cross-link lesions where the neighboring nucleobases in the same DNA strand are covalently bonded. Previous 32P-postlabeling studies suggested that the intrastrand cross-link lesions may arise from Fenton reaction, which also induces the formation of •OH; the structures of the proposed intrastrand cross-link lesions, however, have not been determined. Here, we showed for the first time that the treatment of calf thymus DNA with Cu(II)/H2O2/ascorbate could lead to the formation of an intrastrand cross-link lesion, i.e., G∧T, where the C8 of guanine is covalently bonded to the neighboring 3‘-thymine through its methyl carbon. LC-MS/MS quantification results showed dose−responsive formation of G∧T. In addition, the yield of the intrastrand cross-link was approximately 3 orders of magnitude lower than those of commonly observed single-base lesions, that is, 8-oxo-7,8-dihydro-2‘-deoxyguanosine, 5-(hydroxymethyl)-2‘-deoxyuridine, and 5-formyl-2‘-deoxyuridine. The induction of intrastrand cross-link lesion in calf thymus DNA by Fenton reagents in vitro suggests that this type of lesion might be formed endogenously in mammalian cells.