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ObjectiveThrough improving the potential of vascular endothelial growth factor receptor (VEGFR)-humanized mouse model (hKDR+/+) with C57BL/6N background to allow the growth of different mouse tumor cell lines, to establish novel tumor-bearing mouse models which can support in vivo tumorigenesis of different mouse tumor cell lines and be used to evaluate drugs targeting VEGFR. Methods Firstly, a method to evaluate the in vivo activity of antibody targeting VEGFR based on the hKDR+/+ humanized mouse model was established. Recombinant activating gene 1 (Rag1) knockout mice (Rag1-/-) were established using CRISPR/Cas9 technology. Then these Rag1-/- mice were crossed with hKDR+/+ mice to get a double gene modified homozygous hKDR+/+/Rag1-/- mouse model by screening. Finally, tumor cell lines derived from different mouse strains were tested on the double gene-modified mouse model to compare the differences in tumor growth.ResultsAntibodies designed for VEGFR showed significant anti-tumor activity in hKDR+/+ mice, which significantly reduced tumor volume and weight compared with the PBS group (P

The integration of complex oxides with a wide spectrum of functionalities on Si, Ge and flexible substrates is highly demanded for functional devices in information technology. We demonstrate the remote epitaxy of BaTiO3 (BTO) on Ge using a graphene intermediate layer, which forms a prototype of highly heterogeneous epitaxial systems. The Ge surface orientation dictates the outcome of remote epitaxy. Single crystalline epitaxial BTO3-δ films were grown on graphene/Ge (011), whereas graphene/Ge (001) led to textured films. The graphene plays an important role in surface passivation. The remote epitaxial deposition of BTO3-δ follows the Volmer-Weber growth mode, with the strain being partially relaxed at the very beginning of the growth. Such BTO3-δ films can be easily exfoliated and transferred to arbitrary substrates like Si and flexible polyimide. The transferred BTO3-δ films possess enhanced flexoelectric properties with a gauge factor of as high as 1127. These results not only expand the understanding of heteroepitaxy, but also open a pathway for the applications of devices based on complex oxides.

The accurate measurement of the thermal conductivity in a wide range of semiconductors is of great importance for applications like power electronic devices, which is, however, quite challenging. Current measurement methods suffer from limited measurement range, non-accuracy, complexity, etc. We report in this work an effective in situ method for thermal conductivity measurement based on laser-excited Raman spectroscopy, which has the advantages of non-contact, non-destructive, facile preparation, easy operation, and the capability of a large measurement range. The critical relationship parameters correlating Raman peak shifts and temperature change can be extracted by monitoring and fitting the Raman peak movement at different temperatures. Here, the laser with the micrometer scale spot serves as a Raman scattering source and a heat source for the samples. The thermal conductivity of Si, SiC, polycrystalline diamond, and single crystalline diamond at room temperature was determined to be 140.2 ± 14.4, 414.7 ± 26.2, 1372.3 ± 229.0, and 1734.9 ± 280.6 W/(m K), respectively, which are in good agreement with the theoretical prediction. The temperature distribution of the samples was simulated by the finite element method, which confirms the experimental data. These results highlight the feasibility, reliability, and versatility of Raman spectroscopy for measuring semiconductor materials, particularly those with high thermal conductivity. This is of great interest for exploring semiconductor physics and practical applications like power electronic devices. [ABSTRACT FROM AUTHOR]

The application of distributed sensors in smart transmission lines to replace traditional inspection methods is an inevitable trend. Currently, the challenge of energy supply for sensors serves as a bottleneck that hinders the intelligent development of transmission lines. This paper focuses on the application of self‐powered inspection technology based on triboelectric and electromagnetic mechanisms in transmission lines. It proposes a self‐powered temperature and vibration monitoring and warning system (STV‐MWS) for multi‐parameter monitoring of transmission line status. This work utilizes the quasi‐zero stiffness structure and center misalignment design to improve the output performance of STV‐MWS at low vibration amplitude, thereby extending its vibration amplitude response range. The STV‐MWS is capable of harvesting and monitoring vibration of 50 µm and above vibration amplitude and 2–700 Hz vibration frequencies, which fully covers the breeze vibration range of transmission lines. Through the split package design, the flexible deployment of STV‐MWS is achieved, further enhancing its engineering application value. This work can effectively ensure that the transmission line inspection can carry out accurate status monitoring and intelligent analysis in the environment characterized by steep terrain, challenging power extraction, and difficult fault judgment, thereby realizing the visualization and intelligence of the transmission line status. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor receptor 2 (VEGFR2)/KDR plays a critical role in tumor growth, diffusion, and invasion. The amino acid sequence homology of KDR between mouse and human in the VEGF ligand‐binding domain was low, thus the WT mice could not be used to evaluate Abs against human KDR, and the lack of a suitable mouse model hindered both basic research and drug developments. Using the CRISPR/Cas9 technique, we successfully inserted different fragments of the human KDR coding sequence into the chromosomal mouse Kdr exon 4 locus to obtain an hKDR humanized mouse that can be used to evaluate the marketed Ab ramucirumab. In addition, the humanized mAb VEGFR‐HK19 was developed, and a series of comparative assays with ramucirumab as the benchmark revealed that VEGFR‐HK19 has higher affinity and superior antiproliferation activity. Moreover, VEGFR‐HK19 selectively inhibited tumor growth in the hKDR mouse model but not in WT mice. The most important binding epitopes of VEGFR2‐HK19 are D257, L313, and T315, located in the VEGF binding region. Therefore, the VEGFR2‐HK19 Ab inhibits tumor growth by blocking VEGF‐induced angiogenesis, inflammation, and promoting apoptosis. To our best knowledge, this novel humanized KDR mouse fills the gaps both in an animal model and the suitable in vivo evaluation method for developing antiangiogenesis therapies in the future, and the newly established humanized Ab is expected to be a drug candidate possibly benefitting tumor patients. [ABSTRACT FROM AUTHOR]

The integration of complex oxides with a wide spectrum of functionalities on Si, Ge and flexible substrates is highly demanded for functional devices in information technology. We demonstrate the remote epitaxy of BaTiO3 (BTO) on Ge using a graphene intermediate layer, which forms a prototype of highly heterogeneous epitaxial systems. The Ge surface orientation dictates the outcome of remote epitaxy. Single crystalline epitaxial BTO3-δ films were grown on graphene/Ge (011), whereas graphene/Ge (001) led to textured films. The graphene plays an important role in surface passivation. The remote epitaxial deposition of BTO3-δ follows the Volmer-Weber growth mode, with the strain being partially relaxed at the very beginning of the growth. Such BTO3-δ films can be easily exfoliated and transferred to arbitrary substrates like Si and flexible polyimide. The transferred BTO3-δ films possess enhanced flexoelectric properties with a gauge factor of as high as 1127. These results not only expand the understanding of heteroepitaxy, but also open a pathway for the applications of devices based on complex oxides. The integration of epitaxial complex oxides on semiconductor and flexible substrates is required but challenging. Here, the authors report the highly heterogeneous epitaxy of transferrable BaTiO3-δ membrane with enhanced flexoelectricity on Ge (011). [ABSTRACT FROM AUTHOR]

Future synaptic simulation using resistance random access memory (RRAM) requires higher reliability and lower power consumption of the devices and understanding of the correlation of the materials with their multi-level resistance switching (RS) properties. Using O3 pretreatment on a TiN electrode, this work highlights the significant role of the interface in the enhancement of the reliability and the power consumption of HfO2-based RRAM devices. X-ray photoelectron spectroscopy investigations indicate increases of the TiON and TiO2 components with the augmentation of the number of O3 treatment cycles, which strongly impacts the RS properties of the Pt/HfO2/TiN devices. Optimal RS properties were obtained for 20 O3 pulse-pretreated devices, which were used to emulate biological synapses after an annealing process. Analog memory properties, including analog set and reset in DC mode and potentiation/depression based on two types of designed pulses, have been achieved. Finally, one of the biological synapse learning rules, spike-timing-dependent plasticity, was successfully emulated. These results, avoiding the conventional route based on dual-layer insulators, are of significance for synaptic simulation using interface-engineered single-layer HfO2 RRAM and further reveal the internal mechanism of HfO2-based electron synapses. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG), as a new technique for energy capture, has unique advantages in harvesting high‐entropy energy. In view of the wind‐induced vibration characteristics of power transmission lines, the symmetric elastic bistable triboelectric nanogenerator (EB‐TENG) is introduced in this work. The core component of the EB‐TENG is the elastic bistable cantilever beam structure, which is designed by introducing an elastic perturbation structure to the conventional cantilever beam. This beam results in several sub‐resonance frequencies in addition to the natural frequencies, which broadens the frequency band of the EB‐TENG. In addition, the EB‐TENG adopts a symmetrical cantilever beam to ensure effective harvesting of vibration energy, even in situations of self‐tilting and external tilting vibration. The experimental outcomes confirm that the EB‐TENG can significantly harvest vibration energy in the 7–60 Hz frequency range and delivers the maximum peak power of 2.846 mW, which meets the major vibration frequency range of power transmission lines under the action of breeze. Finally, self‐powered strategy based on EB‐TENG online monitoring devices (such as tower obstruction lights, temperature and humidity sensors, and line high temperature wireless alarms) is constructed. This work helps promote the application of in‐situ self‐powered monitoring based on TENG in smart transmission lines. [ABSTRACT FROM AUTHOR]

The accurate estimation of the temperature distribution of the GaN based power devices and optimization of the device structure is of great significance to possibly solve the self-heating problem, which hinders the further enhancement of the device performances. We present here the operando temperature measurement with high spatial resolution using Raman spectroscopy of AlGaN/GaN high electron mobility transistors (HEMTs) with different device structures and explore the optimization of the device thermal design accordingly. The lateral and depth temperature distributions of the single-finger HEMT were characterized. The channel temperature and self-heating effect of the device under different bias voltages were investigated. By incorporating the two-dimensional electrothermal simulation, the hotspot position can be clearly observed under the gate edge near the drain side. The channel temperature of the multi-finger HEMT was further measured and the experiment results were in agreement with the three-dimensional finite element analysis simulation results. The device structure of the multi-finger device, including the gate width, gate pitch, structure layout, substrate materials, and thickness, were then theoretically optimized to improve the heat dissipation. The peak channel temperature of the device can be reduced by 70 °C when the substrate is substituted from silicon carbide to a single crystalline diamond. These results are of great interest for the thermal management of GaN HEMT power devices and further device performance improvement., (© 2025 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

The potential in a synaptic simulation for neuromorphic computation has revived the research interest of resistive random access memory (RRAM). However, novel applications require reliable multilevel resistive switching (RS), which still represents a challenge. We demonstrate in this work the achievement of reliable HfO 2 -based RRAM devices for synaptic simulation by performing the Al doping and the postdeposition annealing (PDA). Transmission electron microscopy and operando hard X-ray photoelectron spectroscopy results reveal the positive impact of Al doping on the formation of oxygen vacancies. Detailed I - V characterizations demonstrate that the 16.5% Al doping concentration leads to better RS properties of the device. In comparison with the other reported results based on HfO 2 RRAM, our devices with 16.5% Al-doping and PDA at 450 °C show better reliable multilevel RS (∼20 levels) performance and an increased on/off ratio. The 16.5% Al:HfO 2 sample with PDA at 450 °C shows good potentiation/depression characteristics with low pulse width (10 μs) along with a good On/Off ratio (>1000), good data retention at room temperature, and high temperature and good program/erase endurance characteristics with a pulse width of 50 ns. The synapse features including potentiation, depression, and spike time-dependent plasticity were successfully achieved using optimized Al-HfO 2 RRAM devices. Our results demonstrate the beneficial effects of Al doping and PDA on the enhancement of the performances of RRAM devices for the synaptic simulation in neuromorphic computing applications.