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A compressive near-field millimeter wave (MMW) imaging algorithm is proposed. From the compressed sensing (CS) theory, the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-sampled sparse data. The Gini index (GI) has been founded that it is the only sparsity measure that has all sparsity attributes that are called Robin Hood, Scaling, Rising Tide, Cloning, Bill Gates, and Babies. By combining the total variation (TV) operator, the GI-TV mixed regularization introduced compressive near-field MMW imaging model is proposed. In addition, the corresponding algorithm based on a primal-dual framework is also proposed. Experimental results demonstrate that the proposed GI-TV mixed regularization algorithm has superior convergence and stability performance compared with the widely used l1-TV mixed regularization algorithm.

Atomically precise control of the structure and coordination of protein-protected Au nanoclusters remains a challenge. Here, the authors synthesize and characterize a multinuclear Au nanocluster using a 4-fold symmetric axis channel of an apo-ferritin cage as a scaffold, and identify key protein residues during the Au accumulation process.

Great challenges exist in producing reliable welding between metals and polymer composites. In this study, self‐riveting welding (SRW) is employed to obtain metal–polymer hybrid joints with high load‐bearing capability. In this investigation, it is shown that the SRW joints with a prefabricated hole of 5.8 mm in diameter are characterized by fewer void defects with sufficient polymer filling, a tightly bonded joint interface, and a relatively uniform stress distribution along the joint interface during the tensile test, leading to the high load‐bearing capability of the SRW joints. The maximum average tensile force is 1.5 kN. The fracture occurs across the polymer composite rather than along the joint interface. In the results, it is shown that SRW has the potential to be developed into a method for fabricating reliable hybrid joints for the aerospace and automotive industries. [ABSTRACT FROM AUTHOR]

Chemotherapy‐based combination regimens are recommended as first‐line treatment for colorectal cancer. However, multidrug resistance (MDR) and limited drug infiltration in tumor microenvironment remain critical challenges. Herein, a pH/redox dual activated supramolecular DAS@CD‐OxPt (IV) nanoparticles (NPs) via host‐guest molecular recognition to achieve relay drugs delivery of active oxaliplatin (OxPt (IV)) and Src inhibitor dasatinib (DAS) between tumor cells is developed. DAS@CD‐OxPt (IV) NPs exhibit prolonged circulation in the blood and intra‐tumoral retention. Triggered by the endo/lysosome (pH 5.0), flexible DAS@CD‐OxPt (IV) NPs exhibited proton‐driven in situ assembly to form nanofiber in tumor cells. Dual chemotherapeutic agents released from DAS@CD‐OxPt (IV) NPs synergistically cause irreversible DNA damage by blocking p53‐mediated DNA repair. Supramolecular nanofibers can further serve as the "ammunition depot" to continuously release drugs from dying cells and transport them into neighboring tumor cells, leading to domino‐like cell death and enhanced immunogenicity. Furthermore, DAS@CD‐OxPt (IV) NPs combined with immune checkpoint blockade (ICB) therapy strikingly suppress CT26 tumor growth and pulmonary metastasis. [ABSTRACT FROM AUTHOR]

Aiming at the functional self-lubricating liquid film assisted in-mold micro assembly molding of the micro universal spherical revolute motion pair, the key technical issue to achieve precise control of its manufacturing accuracy is to clarify the multi field collaborative coupling evolution law among the diameter manufacturing tolerance of the micro assembly interface, viscoelastic thermal fluid solid coupling impact load, the thickness of continuous phase transformation evolution zone, thermal viscoelastic plastic stress, and melt viscoelastic characteristics. The research results indicated that the diameter manufacturing tolerance of the micro assembly interface was controlled by the viscoelastic characteristics of the secondary injection molding melt. When the reference viscosity increased from 2 267 to 15 000 Pa*s, the diameter manufacturing tolerance of the micro assembly interface increased by 72. 7 % from 11 to 19 μm. When the relaxation time increased from 0. 05 to 0. 25 s, the diameter manufacturing tolerance of the micro assembly interface decreased by 38. 7 % from 31 to 19 μm. To meet the industry standard of dimensional manufacturing tolerance technical indicators ≤ 30 μm, it is not advisable to use a high elastic melt with a relaxation time ≤ 0. 05 s for the functional self-lubricating liquid film assisted in-mold micro assembly molding. [ABSTRACT FROM AUTHOR]

The cascode gallium nitride high electron mobility transistors (GaN HEMTs) are very vulnerable to self‐sustained turn‐off oscillation due to their cascode configuration. This paper presents a design approach for the RC snubber of cascode GaN HEMTs to achieve the optimized noise‐loss trade‐off. At first, an analytical model is proposed to describe the instability of cascode GaN HEMTs‐based test circuits utilizing RC snubber. Based on the model, an analytical approach is proposed to achieve two optimum RC snubber designs S1 and S2. The design S1 can satisfactorily dampen the oscillation with minimum switching losses. The design S2 achieves maximum effective damping on the oscillation at a minimized cost of additional power losses. In the end, the accuracy of the proposed model is validated by the double‐pulse test and good agreement is obtained. [ABSTRACT FROM AUTHOR]

Given that tumor microenvironment (TME) exerts adverse impact on the therapeutic response and clinical outcome, robust TME modulators may significantly improve the curative effect and increase survival benefits of cancer patients. Here, Au nanodots‐anchored CoFe2O4 nanoflowers with PEGylation (CFAP) are developed to respond to TME cues, aiming to exacerbate redox dyshomeostasis for efficacious antineoplastic therapy under ultrasound (US) irradiation. After uptake by tumor cells, CFAP with glucose oxidase (GOx)‐like activity can facilitate glucose depletion and promote the production of H2O2. Multivalent elements of Co(II)/Co(III) and Fe(II)/Fe(III) in CFAP display strong Fenton‐like activity for·OH production from H2O2. On the other hand, energy band structure CFAP is superior for US‐actuated 1O2 generation, relying on the enhanced separation and retarded recombination of e−/h+ pairs. In addition, catalase‐mimic CFAP can react with cytosolic H2O2 to generate molecular oxygen, which may increase the product yields from O2‐consuming reactions, such as glucose oxidation and sonosensitization processes. Besides the massive production of reactive oxygen species, CFAP is also capable of exhausting glutathione to devastate intracellular redox balance. Severe immunogenic cell death and effective inhibition of solid tumor by CFAP demonstrates the clinical potency of such heterogeneous structure and may inspire more relevant designs for disease therapy. [ABSTRACT FROM AUTHOR]

Light quality and sucrose-induced osmotic stress are known to cause anthocyanin synthesis in detached Lycium ruthenicum leaves. To identify the mechanisms by which the kind of light quality and sucrose concentration are induced, here, we conducted transcriptome sequencing in detached L. ruthenicum leaves treated with different qualities of light and sucrose concentrations. Leaves treated with blue light or sucrose showed a significantly increased total anthocyanins content compared to those treated with white light. Delphinidin-3-O-rutinoside and delphinidin-3-O-glucoside production were differentially regulated by the BL(−S), BL(+S), and WL(+S) treatments. The structural genes CHS, CHI, F3′H, F3′5′H, ANS, and UFGT were significantly up-regulated in leaves treated with blue light or sucrose. Leaves treated with blue light additionally showed up-regulation of the light photoreceptors CRY1, PIF3, COP1, and HY5. The anthocyanin-related genes NCED1, PYR/PYL, PP2C, SnRK2, and ABI5 were significantly up-regulated in leaves treated with sucrose, promoting adaptability to sucrose osmotic stress. Co-expression and cis-regulatory analyses suggested that HY5 and ABI5 could regulate LrMYB44 and LrMYB48 through binding to the G-box element and ABRE element, respectively, inducing anthocyanin synthesis in response to blue light or sucrose treatment. Candidate genes responsive to blue light or sucrose osmotic stress in the anthocyanin biosynthesis pathway were validated through quantitative reverse transcription PCR. These findings deepen our understanding of the mechanisms by which blue light and sucrose-induced osmotic stress regulate anthocyanin synthesis, providing valuable target genes for the future improvement in anthocyanin production in L. ruthenicum.