Background Cuproptosis is a newly discovered programmed cell death dependent on mitochondrial respiratory disorder induced by copper overload. Pyruvate dehydrogenase E1 subunit beta (PDHB) is one of ...the cuproptosis genesand is a nuclear-encoded pyruvate dehydrogenase, which catalyzes the conversion of pyruvate to acetyl coenzyme A. However, the mechanism of PDHB in clear cell renal cell carcinoma (ccRCC) remains unclear. Methods We used data from TCGA and GEO to assess the expression of PDHB in normal and tumor tissues. We further analyzed the relationship between PDHB and somatic mutations and immune infiltration. Finally, we preliminarily explored the impact of PDHB on ccRCC. Results The expression level of PDHB was lower in tumor tissue compared with normal tissue. Meanwhile, the expression level of PDHB was also lower in high-grade tumors than low-grade tumors. PDHB is positively correlated with prognosis in ccRCC. Furthermore, PDHB may be associated with decreased risk of VHL, PBRM1 and KDM5C mutations. In 786-O cells, copper chloride could promote the expression of cuproptosis genes (DLAT, PDHB and FDX1) and inhibit cell growth. Last but not least, we found that PDHB could inhibit the proliferation and migration of ccRCC cells. Conclusion Our results demonstrated that PDHB could inhibit the proliferation, migration and invasion in ccRCC cells, which might be a prognostic predictor of ccRCC. Targeting this molecular might provide a new therapeutic strategy for patients with advanced ccRCC. Keywords: Cuproptosis, PDHB, Clear cell renal cell carcinoma, Tumor immune microenvironment
Compressive sensing (CS) has been introduced into inverse synthetic aperture radar (ISAR) imaging with partial measurements. However, in the case of transmitting sparse frequency-stepped chirp signal ...(FSCS), the CS-based method will produce an irregular range cell migration (IRCM) problem in the recovered high-resolution range profiles (HRRPs). The IRCM is induced by the basis mismatch problem in CS, and it will degrade the ISAR image. To obviate the IRCM, an atomic norm minimization (ANM) method is proposed in this letter. By reformulating the ANM as a semidefinite program (SDP), the echo with full FSCS can be recovered using off-the-shelf SDP solvers. Thus, HRRPs without IRCM can be achieved via the conventional inverse fast Fourier transform. As a result, an improved ISAR image will be obtained. Real data results demonstrate the advantages of the proposed method over the CS-based and matrix completion-based methods.
The rapid development of portable and wearable electronic devices is responding to the urgent demand for high-efficiency flexible energy storage devices. Flexible supercapacitors, showing long cycle ...life, high power density, and good safety, are considered ideal candidates. Nevertheless, the relatively low energy density restricts their practical applications. With a large dielectric constant of 18–46, Ta
2
O
5
-based materials typically exhibit excellent electron-binding ability, which is critical for enhancing the energy density of supercapacitors. In this work, the free-standing β-Ta
2
O
5
/single-walled carbon nanotubes (SWCNTs) composite film was prepared, with a high β-Ta
2
O
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loading of over 70%. By anchoring β-Ta
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nanoparticles onto the surface of SWCNTs, the system’s flexibility and conductivity were significantly enhanced, which also facilitated the intercalation electrodynamics of metal cations. As a result, the flexible β-Ta
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O
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/SWCNTs film exhibits excellent Li-ion storage performance, with a high volumetric specific capacitance of 392.3 F cm
−3
at the scan rate of 10 mV s
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and 198.9 F cm
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at 500 mV s
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. In addition, the asymmetric device, assembled by the β-Ta
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/SWCNTs and activated carbon films, shows a high energy density of 45.5 Wh kg
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at the power density of 10.8 kW kg
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. This technique opens up a new avenue for improving the energy density and rate performance of flexible supercapacitors.
The design of movement trajectories for mobile sink plays an important role in data gathering for Wireless Sensor Networks (WSNs), as it affects the network coverage, and packet delivery ratio, as ...well as the network lifetime. In some scenarios, the whole network can be divided into subareas where the nodes are randomly deployed. The node densities of these subareas are quite different, which may result in a decreased packet delivery ratio and network lifetime if the movement trajectory of the mobile sink cannot adapt to these differences. To address these problems, we propose an adjustable trajectory design method based on node density for mobile sink in WSNs. The movement trajectory of the mobile sink in each subarea follows the Hilbert space-filling curve. Firstly, the trajectory is constructed based on network size. Secondly, the adjustable trajectory is established based on node density in specific subareas. Finally, the trajectories in each subarea are combined to acquire the whole network's movement trajectory for the mobile sink. In addition, an adaptable power control scheme is designed to adjust nodes' transmitting range dynamically according to the movement trajectory of the mobile sink in each subarea. The simulation results demonstrate that the proposed trajectories can adapt to network changes flexibly, thus outperform both in packet delivery ratio and in energy consumption the trajectories designed only based on the network size and the whole network node density.
Recently, human hair keratin has been widely studied and applied in clinical fields due to its good histocompatibility, biocompatibility, and biodegradability. However, the regenerated keratin from ...human hair cannot be electrospun alone because of its low molecular weight. Herein, gamma polyglutamic acid (γ-PGA) was first selected to fabricate smooth and uniform γ-PGA/keratin composite scaffolds with excellent biocompatibility and biodegradability by electrospinning technology and a chemical cross-linking method in this study. The effect of electrospinning parameters on the structure and morphology, the mechanism of chemical cross-linking, biocompatibility in vitro cell culture experiments, and biodegradability in phosphate-buffered saline buffer solution and trypsin solution of the γ-PGA/keratin electrospun nanofibrous scaffolds (ENS) was studied. The results show that the cross-linked γ-PGA/keratin ENSs had excellent water stability and biodegradability. The γ-PGA/keratin ENSs showed better biocompatibility in promoting cell adhesion and cell growth compared with the γ-PGA ENSs. It is expected that γ-PGA/keratin ENSs will be easily and significantly used in tissue engineering to repair or regenerate materials.
Caused by the platform movement, slowly moving targets on the ground will be hidden by the stationary clutter in the Doppler domain for an airborne passive radar system. In this paper, the signal ...model of airborne passive radar used for ground moving target indication purpose is established at first. Then, the space–time adaptive processing technique is adopted to suppress the strong clutter. Because of the poorer range resolution than active radar, independently and identically distributed training range cells are more difficult to obtain for passive radar. To address this problem, the sparsity of clutter in the space–time domain is exploited and a jointly sparse matrix recovery model is introduced. Furthermore, a parameter-searched two-dimensional multiple measurement vectors based orthogonal matching pursuit (MOMP) algorithm is proposed to solve the off-grid (basis mismatch) problem and reduce the computational complexity at the same time, and thus to more accurately and effectively estimate the clutter covariance matrix. Simulation results with digital TV signal as the illuminator source are shown to demonstrate the effectiveness of the proposed algorithm to determine the Doppler frequency, spatial frequency, and relative bistatic range of the moving targets on the ground.
The unstable link quality in wireless sensor networks (WSNs) directly affects the success rate of data transmission. The retransmission mechanism is one of the commonly used methods to solve this ...problem. However, too many retransmissions could lower the communication efficiency. Therefore, to reduce retransmissions while guaranteeing the communication reliability in WSNs, this study introduces the NarrowBand Internet of Things (NB‐IoT) technology, and builds a network including both sensor and NB‐IoT nodes. The NB‐IoT node is designed to support both the radio frequency and the NarrowBand communication modes; thus it can communicate with both sensor nodes and NB‐IoT base stations. Further, the communication reliability metrics considering both the link quality and the number of retransmissions in different communication modes are defined, based on which, an adaptive communication reliability algorithm is proposed to switch the communication modes of nodes. The simulation results verify that the proposed algorithm can achieve higher success rate with less end‐to‐end delay and flexibly control the cost on NB‐IoT communication.
Multi-UAV (unmanned aerial vehicle) mission collaboration is one of the current research hotspots in automation, artificial intelligence, and other fields. The difficulty and high cost of real flight ...verification have led to the problem that related knowledge learning focuses on theoretical derivation and ignores technical practice. In this paper, a multi-UAV mission simulation system is designed to show the greatest advantage of its collaborative mission planning results simulated and tested in 3D scenarios. It simultaneously reflects and records changes in UAV position, velocity, status, and other state values. The simulation program can be directly applied to real flight with only a few settings. First, the general system framework is presented. Second, according to the simulation requirements, the key modules involved in the software in the loop are given. Finally, through a path planning test for two UAVs, the effect of the system is demonstrated. The results show that the simulation verification based on the system is consistent with the real flight results in terms of functional implementation. It is applicable to the teaching process of related majors and can also provide support for the realization of many complex tasks in the future.
Nowadays, many applications of heterogeneous sensing wireless sensor networks (WSNs) employ more than one type of sensor nodes to acquire a variety of sensing data sources, which brings the dynamic ...diversity of generated data amount among different network regions. To adapt to that diversity and improve the data gathering efficiency, this paper first analyzes and models the diversity of generated data amount according to the diversities of data generating rate and operating mode among nodes and then proposes a data gathering scheme with a mobile sink. In the scheme, the movement trajectory for the mobile sink is determined by using Hilbert space-filling curve and adjusted dynamically based on the change of data amounts generated in different network regions. A hybrid routing method is also proposed to further reduce the network energy consumption. The simulation results show that the proposed data gathering scheme not only has effective performances on a promoting packet delivery ratio and reducing average energy consumption rate but also has great adaptability to the heterogeneous sensing WSNs.
Continuous loss of cardiomyocytes (CMs) is one of the fundamental characteristics of many heart diseases, which eventually can lead to heart failure. Due to the limited proliferation ability of human ...adult CMs, treatment efficacy has been limited in terms of fully repairing damaged hearts. It has been shown that cell lineage conversion can be achieved by using cell reprogramming approaches, including human induced pluripotent stem cells (hiPSCs), providing a promising therapeutic for regenerative heart medicine. Recent studies using advanced cellular reprogramming-based techniques have also contributed some new strategies for regenerative heart repair. In this review, hiPSC-derived cell therapeutic methods are introduced, and the clinical setting challenges (maturation, engraftment, immune response, scalability, and tumorigenicity), with potential solutions, are discussed. Inspired by the iPSC reprogramming, the approaches of direct cell lineage conversion are merging, such as induced cardiomyocyte-like cells (iCMs) and induced cardiac progenitor cells (iCPCs) derived from fibroblasts, without induction of pluripotency. The studies of cellular and molecular pathways also reveal that epigenetic resetting is the essential mechanism of reprogramming and lineage conversion. Therefore, CRISPR techniques that can be repurposed for genomic or epigenetic editing become attractive approaches for cellular reprogramming. In addition, viral and non-viral delivery strategies that are utilized to achieve CM reprogramming will be introduced, and the therapeutic effects of iCMs or iCPCs on myocardial infarction will be compared. After the improvement of reprogramming efficiency by developing new techniques, reprogrammed iCPCs or iCMs will provide an alternative to hiPSC-based approaches for regenerative heart therapies, heart disease modeling, and new drug screening.
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