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1.
Nat Commun ; 15(1): 3869, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38719933

ABSTRACT

Solving ill-posed inverse problems typically requires regularization based on prior knowledge. To date, only prior knowledge that is formulated mathematically (e.g., sparsity of the unknown) or implicitly learned from quantitative data can be used for regularization. Thereby, semantically formulated prior knowledge derived from human reasoning and recognition is excluded. Here, we introduce and demonstrate the concept of semantic regularization based on a pre-trained large language model to overcome this vexing limitation. We study the approach, first, numerically in a prototypical 2D inverse scattering problem, and, second, experimentally in 3D and 4D compressive microwave imaging problems based on programmable metasurfaces. We highlight that semantic regularization enables new forms of highly-sought privacy protection for applications like smart homes, touchless human-machine interaction and security screening: selected subjects in the scene can be concealed, or their actions and postures can be altered in the reconstruction by manipulating the semantic prior with suitable language-based control commands.

2.
Nat Commun ; 15(1): 3838, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38714685

ABSTRACT

The powerful capability of reconfigurable intelligent surfaces (RISs) in tailoring electromagnetic waves and fields has put them under the spotlight in wireless communications. However, the current designs are criticized due to their poor frequency selectivity, which hinders their applications in real-world scenarios where the spectrum is becoming increasingly congested. Here we propose a filtering RIS to feature sharp frequency-selecting and 2-bit phase-shifting properties. It permits the signals in a narrow bandwidth to transmit but rejects the out-of-band ones; meanwhile, the phase of the transmitted signals can be digitally controlled, enabling flexible manipulations of signal propagations. A prototype is designed, fabricated, and measured, and its high quality factor and phase-shifting characteristics are validated by scattering parameters and beam-steering phenomena. Further, we conduct a wireless communication experiment to illustrate the intriguing functions of the RIS. The filtering behavior enables the RIS to perform wireless signal manipulations with anti-interference ability, thus showing big potential to advance the development of next-generation wireless communications.

3.
EClinicalMedicine ; 72: 102622, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38745965

ABSTRACT

Background: The role of transarterial chemoembolization (TACE) in the treatment of advanced hepatocellular carcinoma (HCC) is unconfirmed. This study aimed to assess the efficacy and safety of immune checkpoint inhibitors (ICIs) plus anti-vascular endothelial growth factor (anti-VEGF) antibody/tyrosine kinase inhibitors (TKIs) with or without TACE as first-line treatment for advanced HCC. Methods: This nationwide, multicenter, retrospective cohort study included advanced HCC patients receiving either TACE with ICIs plus anti-VEGF antibody/TKIs (TACE-ICI-VEGF) or only ICIs plus anti-VEGF antibody/TKIs (ICI-VEGF) from January 2018 to December 2022. The study design followed the target trial emulation framework with stabilized inverse probability of treatment weighting (sIPTW) to minimize biases. The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), objective response rate (ORR), and safety. The study is registered with ClinicalTrials.gov, NCT05332821. Findings: Among 1244 patients included in the analysis, 802 (64.5%) patients received TACE-ICI-VEGF treatment, and 442 (35.5%) patients received ICI-VEGF treatment. The median follow-up time was 21.1 months and 20.6 months, respectively. Post-application of sIPTW, baseline characteristics were well-balanced between the two groups. TACE-ICI-VEGF group exhibited a significantly improved median OS (22.6 months [95% CI: 21.2-23.9] vs 15.9 months [14.9-17.8]; P < 0.0001; adjusted hazard ratio [aHR] 0.63 [95% CI: 0.53-0.75]). Median PFS was also longer in TACE-ICI-VEGF group (9.9 months [9.1-10.6] vs 7.4 months [6.7-8.5]; P < 0.0001; aHR 0.74 [0.65-0.85]) per Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1. A higher ORR was observed in TACE-ICI-VEGF group, by either RECIST v1.1 or modified RECIST (41.2% vs 22.9%, P < 0.0001; 47.3% vs 29.7%, P < 0.0001). Grade ≥3 adverse events occurred in 178 patients (22.2%) in TACE-ICI-VEGF group and 80 patients (18.1%) in ICI-VEGF group. Interpretation: This multicenter study supports the use of TACE combined with ICIs and anti-VEGF antibody/TKIs as first-line treatment for advanced HCC, demonstrating an acceptable safety profile. Funding: National Natural Science Foundation of China, National Key Research and Development Program of China, Jiangsu Provincial Medical Innovation Center, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, and Nanjing Life Health Science and Technology Project.

4.
Am J Surg Pathol ; 48(6): 681-690, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38682454

ABSTRACT

Acinic cell carcinoma of the salivary gland (AciCC) is a low-grade carcinoma characterized by the overexpression of the transcription factor nuclear receptor subfamily 4 group A member 3 (NR4A3). AciCC has been the subject of a few molecular research projects. This study delves into AciCC's molecular landscape to identify additional alterations and explore their clinical implications. RNA sequencing and immunohistochemical staining for markers NR4A3/NR4A2, DOG-1, S100, and mammaglobin were utilized on 41 AciCCs and 11 secretory carcinoma (SC) samples. NR4A3 was evident in 35 AciCCs, while the residual 6 were NR4A3-negative and NR4A2-positive; SC samples were consistently NR4A3-negative. A novel fusion, PON3 exon 1- LCN1 exon 5, was detected in 9/41 (21.9%) AciCCs, exhibiting a classical histologic pattern with serous cell components growing in solid sheets alongside the intercalated duct-like component. Clinical follow-up of 39 patients over a median of 59 months revealed diverse prognostic outcomes: 34 patients exhibited no disease evidence, whereas the remaining 5 experienced poorer prognosis, involving local recurrence, lymph node, and distant metastasis, and disease-associated death, 4 of which harbored the PON3::LCN1 fusion. In addition, the HTN3::MSANTD3 fusion was recurrently identified in 7/41 AciCC cases. SC patients lacked both fusions. Immunohistochemistry uncovered differential expression of DOG-1, S100, and mammaglobin across samples, providing nuanced insights into their roles in AciCC. This study accentuates PON3::LCN1 and HTN3::MSANTD3 fusions as recurrent molecular events in AciCC, offering potential diagnostic and prognostic utility and propelling further research into targeted therapeutic strategies.


Subject(s)
Biomarkers, Tumor , Carcinoma, Acinar Cell , Nuclear Receptor Subfamily 4, Group A, Member 2 , Salivary Gland Neoplasms , Humans , Male , Carcinoma, Acinar Cell/genetics , Carcinoma, Acinar Cell/pathology , Female , Salivary Gland Neoplasms/genetics , Salivary Gland Neoplasms/pathology , Salivary Gland Neoplasms/mortality , Salivary Gland Neoplasms/metabolism , Salivary Gland Neoplasms/chemistry , Middle Aged , Biomarkers, Tumor/genetics , Biomarkers, Tumor/analysis , Adult , Aged , Nuclear Receptor Subfamily 4, Group A, Member 2/genetics , Nuclear Receptor Subfamily 4, Group A, Member 2/analysis , Receptors, Steroid/genetics , Receptors, Steroid/metabolism , Receptors, Thyroid Hormone/genetics , Receptors, Thyroid Hormone/analysis , Receptors, Thyroid Hormone/metabolism , Young Adult , Gene Fusion , Aged, 80 and over , DNA-Binding Proteins/genetics , Oncogene Proteins, Fusion/genetics , Immunohistochemistry
5.
J Dent Sci ; 19(2): 885-893, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38618107

ABSTRACT

Background/purpose: There is inconsistent evidence regarding whether the botulinum toxin A (BTA) injection can relieve pain caused by bruxism. This study aimed to estimate the efficiency of BTA injection in relieving pain caused by bruxism at different follow-up periods. Materials and methods: Five electronic databases were searched from 2005 to 2022 using search terms related to botulinum toxin and bruxism. Only controlled clinical trials were included. Two investigators reviewed each article and discussed any disagreements until a consensus was reached. Pain outcomes as evaluated by the visual analogue scale (VAS) were subjected to single-arm and Bayesian network meta-analyses. Pooling data were measured by a random-effects model. Results: Eleven studies with a total of 365 bruxism patients were included. According to the single-arm analyses of the pooled data, the reduction in bruxism-related pain after BTA injection measured 4.06 points (95% CI = 3.37 to 4.75) on the VAS, and the pain relief was significant in the first 6 months after treatment (P < 0.01). According to the Bayesian analysis, BTA also resulted in significantly greater pain relief than oral splinting (mean difference (MD), -1.5; 95% credible interval (CrI) = -2.7 to -0.19) or saline injection (MD, -3.3; 95% CrI = -6.2 to -0.32). Conclusion: BTA significantly relieves the pain of bruxism for 6 months after injection, and its therapeutic efficacy was higher than that of oral splinting. Nevertheless, further long-term follow-up randomized controlled trials comparing BTA with other management or drugs are warranted.

6.
Blood Rev ; 65: 101196, 2024 May.
Article in English | MEDLINE | ID: mdl-38604819

ABSTRACT

Chronic myeloid leukaemia (CML) is caused by BCR::ABL1. Tyrosine kinase-inhibitors (TKIs) are the initial therapy. Several organizations have reported milestones to evaluate response to initial TKI-therapy and suggest when a change of TKI should be considered. Achieving treatment-free remission (TFR) is increasingly recognized as the optimal therapy goal. Which TKI is the best initial therapy for which persons and what depth and duration of molecular remission is needed to achieve TFR are controversial. In this review we discuss these issues and suggest future research directions.


Subject(s)
Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Protein Kinase Inhibitors , Humans , Protein Kinase Inhibitors/therapeutic use , Fusion Proteins, bcr-abl/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/etiology , Remission Induction , Biology
7.
Nat Commun ; 15(1): 2824, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38561378

ABSTRACT

Coherent perfect absorption (CPA) and amplification of electromagnetic waves are converse phenomena, where incoming radiations are coherently dissipated or amplified by structured incidences. Realizing such two phenomena simultaneously in a single device may benefit various applications such as biological sensing, photo detection, radar stealth, solar-thermal energy sharing, and wireless communications. However, previous experimental realizations of CPA and amplification generally require precise controls to the loss and gain of a system, making dynamic switching between the absorption and amplification states a challenge. To this end, we propose a nonlinear approach to realize CPA and parametric amplification (PA) simultaneously at the same frequency and demonstrate experimentally dynamic switch from the CPA to PA states in a judiciously designed nonlinear spoof plasmonic waveguide. The measured output signal gain can be continuously tuned from -33 dB to 22 dB in a propagation length of 9.2 wavelengths. Compared to the traditional linear CPA, our approach relaxes the stringent requirements on device dimensions and material losses, opening a new route to actively modulate the electromagnetic waves with giant amplification-to-absorption contrast in a compact platform. The proposed nonlinear plasmonic platform has potential applications in on-chip systems and wireless communications.

8.
Arch Microbiol ; 206(4): 141, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38441685

ABSTRACT

A strictly anaerobic, motile bacterium, designated as strain Ai-910T, was isolated from the sludge of an anaerobic digestion tank in China. Cells were Gram-stain-negative rods. Optimal growth was observed at 38 °C (growth range 25-42 °C), pH 8.5 (growth range 5.5-10.5), and under a NaCl concentration of 0.06% (w/v) (range 0-2.0%). Major cellular fatty acids were iso-C15 : 0 and anteiso-C15 : 0. The respiratory quinone was MK-7. Using xylose as the growth substrate, succinate was produced as the fermentation product. Phylogenetic analysis based on the 16 S rRNA gene sequences indicated that strain Ai-910T formed a distinct phylogenetic lineage that reflects a new genus in the family Marinilabiliaceae, sharing high similarities to Alkaliflexus imshenetskii Z-7010T (92.78%), Alkalitalea saponilacus SC/BZ-SP2T (92.51%), and Geofilum rubicundum JAM-BA0501T (92.36%). Genomic similarity (average nucleotide identity and digital DNA-DNA hybridization) values between strain Ai-910T and its phylogenetic neighbors were below 65.27 and 16.90%, respectively, indicating that strain Ai-910T represented a novel species. The average amino acid identity between strain Ai-910T and other related members of the family Marinilabiliaceae were below 69.41%, supporting that strain Ai-910T was a member of a new genus within the family Marinilabiliaceae. Phylogenetic, genomic, and phenotypic analysis revealed that strain Ai-910T was distinguished from other phylogenetic relatives within the family Marinilabiliaceae. The genome size was 3.10 Mbp, and the DNA G + C content of the isolate was 42.8 mol%. Collectively, differences of the phenotypic and phylogenetic features of strain Ai-910T from its close relatives suggest that strain Ai-910T represented a novel species in a new genus of the family Marinilabiliaceae, for which the name Xiashengella succiniciproducens gen. nov., sp. nov. was proposed. The type strain of Xiashengella succiniciproducens is Ai-910T (= CGMCC 1.17893T = KCTC 25,304T).


Subject(s)
Bacteria , Succinic Acid , Anaerobiosis , Phylogeny , Succinates , DNA
9.
Eur J Pharmacol ; 970: 176491, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38503399

ABSTRACT

Alzheimer's disease (AD) is a progressive neurodegenerative disease with the hallmark of aggregation of beta-amyloid (Aß) into extracellular fibrillar deposition. Accumulating evidence suggests that soluble toxic Aß oligomers exert diverse roles in neuronal cell death, oxidative stress, neuroinflammation, and the eventual pathogenesis of AD. Aß is derived from the sequential cleavage of amyloid-ß precursor protein (APP) by ß-secretase (BACE1) and γ-secretase. The current effect of single targeting is not ideal for the treatment of AD. Therefore, developing multipotent agents with multiple properties, including anti-Aß generation and anti-Aß aggregation, is attracting more attention for AD treatment. Previous studies indicated that Quercetin was able to attenuate the effects of several pathogenetic factors in AD. Here, we showed that naturally synthesized Quercetin-3-O-glc-1-3-rham-1-6-glucoside (YCC31) could inhibit Aß production by reducing ß-secretase activity. Further investigations indicated that YCC31 could suppress toxic Aß oligomer formation by directly binding to Aß. Moreover, YCC31 could attenuate Aß-mediated neuronal death, ROS and NO production, and pro-inflammatory cytokines release. Taken together, YCC31 targeting multiple pathogenetic factors deserves further investigation for drug development of AD.


Subject(s)
Alzheimer Disease , Neurodegenerative Diseases , Humans , Amyloid Precursor Protein Secretases/metabolism , Quercetin/pharmacology , Quercetin/therapeutic use , Cytokines , Aspartic Acid Endopeptidases/metabolism , Aspartic Acid Endopeptidases/therapeutic use , Alzheimer Disease/drug therapy , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/metabolism , Glucosides/therapeutic use
10.
Food Res Int ; 181: 114094, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38448096

ABSTRACT

The detailed dynamics of small molecular nonvolatile chemical and bacterial diversities, as well as their relationship are still unclear in the manufacturing process of Keemun black tea (KMBT). Herein, mass spectrometry-based untargeted metabolomics, Feature-based Molecular Networking (FBMN) and bacterial DNA amplicon sequencing were used to investigate the dense temporal samples of the manufacturing process. For the first time, we reveal that the pyrogallol-type catechins are oxidized asynchronously before catechol-type catechins during the black tea processing. Rolling is the key procedure for forming the small molecular nonvolatile metabolite profile (SMNMetProf), increasing the metabolite richness, and then shaping the bacterial community structure in the KMBT manufacturing process, which decreases both molecular weight and molecular polarity of the small molecular nonvolatile metabolites. The SMNMetProf of black tea is formed by the endogenous enzymatic oxidation of tea leaves, rather than bacterial fermentation.


Subject(s)
Camellia sinensis , Catechin , Tea , Commerce , DNA, Bacterial/genetics
11.
Adv Sci (Weinh) ; : e2306850, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38477543

ABSTRACT

Micro-Doppler effect is a vital feature of a target that reflects its oscillatory motions apart from bulk motion and provides an important evidence for target recognition with radars. However, establishing the micro-Doppler database poses a great challenge, since plenty of experiments are required to get the micro-Doppler signatures of different targets for the purpose of analyses and interpretations with radars, which are dramatically limited by high cost and time-consuming. Aiming to overcome these limits, a low-cost and powerful simulation platform of the micro-Doppler effects is proposed based on time-domain digital coding metasurface (TDCM). Owing to the outstanding capabilities of TDCM in generating and manipulating nonlinear harmonics during wave-matter interactions, it enables to supply rich and high-precision electromagnetic signals with multiple micro-Doppler frequencies to describe the micro-motions of different objects, which are especially favored for the training of artificial intelligence algorithms in automatic target recognition and benefit a host of applications like imaging and biosensing.

12.
Int J Food Microbiol ; 415: 110634, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38401379

ABSTRACT

Escherichia coli is one of the important reservoirs of antimicrobial resistance genes (ARG), which often causes food-borne diseases and clinical infections. Contamination with E. coli carrying clinically important antimicrobial resistance genes in retail meat products can be transmitted to humans through the food chain, posing a serious threat to public health. In this study, a total of 330 E. coli strains were isolated from 464 fresh meat samples from 17 food markets in China, two of which were identified as enterotoxigenic and enteropathogenic E. coli. Whole genome sequencing revealed the presence of 146 different sequence types (STs) including 20 new STs, and 315 different clones based on the phylogenetic analysis, indicating the high genetic diversity of E. coli from retail meat products. Antimicrobial resistance profiles showed that 82.42 % E. coli were multidrug-resistant strains. A total of 89 antimicrobial resistance genes were detected and 12 E. coli strains carried clinically important antimicrobial resistance genes blaNDM-1, blaNDM-5, mcr-1, mcr-10 and tet(X4), respectively. Nanopore sequencing revealed that these resistance genes are located on different plasmids with the ability of horizontal transfer, and their genetic structure and environment are closely related to plasmids isolated from humans. Importantly, we reported for the first time the presence of plasmid-mediated mcr-10 in E. coli from retail meat. This study revealed the high genetic diversity of food-borne E. coli in retail meat and emphasized their risk of spreading clinically important antimicrobial resistance genes.


Subject(s)
Enteropathogenic Escherichia coli , Escherichia coli Infections , Escherichia coli Proteins , Humans , Anti-Bacterial Agents/pharmacology , Escherichia coli Proteins/genetics , Phylogeny , beta-Lactamases/genetics , Drug Resistance, Bacterial/genetics , Meat/analysis , Enteropathogenic Escherichia coli/genetics , Whole Genome Sequencing , Plasmids , Microbial Sensitivity Tests
13.
BMJ Open Gastroenterol ; 11(1)2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38395452

ABSTRACT

OBJECTIVES: The efficacy of transjugular intrahepatic portosystemic shunt (TIPS) plus extrahepatic collateral embolisation (TIPS+E) in reducing rebleeding and hepatic encephalopathy (HE) post-TIPS was recently reported in a meta-analysis, but further validation is essential. This study aims to confirm the effectiveness of TIPS+E using real-world data. METHODS: The multicentre retrospective cohort included 2077 patients with cirrhosis who underwent TIPS±E (TIPS: 631, TIPS+E: 1446) between January 2010 and December 2022. Regression and propensity score matching (PSM) were used to adjust for baseline characteristic differences. After PSM, clinical outcomes, including rebleeding, HE, survival and further decompensation (FDC), were analysed. Baseline data from all patients contributed to the construction of prognostic models. RESULTS: After PSM, 1136 matched patients (TIPS+E: TIPS=568:568) were included. TIPS+E demonstrated a significant reduction in rebleeding (HR 0.77; 95% CI 0.59 to 0.99; p=0.04), HE (HR 0.82; 95% CI 0.68 to 0.99; p=0.04) and FDC (HR 0.85; 95% CI 0.73 to 0.99; p=0.04), comparing to TIPS. Significantly, TIPS+E also reduced rebleeding, HE and FDC in subgroup of using 8 mm diameter stents and embolising of gastric varices+spontaneous portosystemic shunts (GV+SPSS). However, there were no differences in overall or subgroup survival analysis. Additionally, the random forest models showed higher accuracy and AUROC comparing to other models. Controlling post-TIPS portal pressure gradient (pPPG) within 7 mm Hg

Subject(s)
Esophageal and Gastric Varices , Hepatic Encephalopathy , Portasystemic Shunt, Transjugular Intrahepatic , Humans , Retrospective Studies , Gastrointestinal Hemorrhage/surgery , Esophageal and Gastric Varices/surgery , Liver Cirrhosis/complications , Liver Cirrhosis/surgery
14.
Adv Mater ; : e2313697, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38364255

ABSTRACT

Programmable metasurface technology can achieve flexible manipulations of electromagnetic waves in real time by adjusting the surface structure and material properties and has shown extraordinary potential in many fields such as wireless communications and the Internet of Things. However, most of the programmable metasurfaces have a common feature: a tail (electrical wires and DC powers), which is difficult to supply in some particular application scenarios such as canyons and mountains. To eliminate the limitation of DC power supply, the programmable metasurface and wireless power transfer technology are combined to propose a tailless information-energy metasurface (IEMS). The tailless IEMS platform can dynamically control electromagnetic waves without relying on an external DC power supply; instead, the required DC power is provided internally by the IEMS platform itself. In the tailless IEMS experiments, the concept is demonstrated through the dynamic regulation of wireless channels and the wireless transmission of DC power. This work provides a self-powered method for programmable metasurfaces, expands the application scenarios, facilitates the miniaturization of systems, and makes it easy to integrate with other systems.

15.
Adv Sci (Weinh) ; 11(17): e2309826, 2024 May.
Article in English | MEDLINE | ID: mdl-38380552

ABSTRACT

Speech recognition becomes increasingly important in the modern society, especially for human-machine interactions, but its deployment is still severely thwarted by the struggle of machines to recognize voiced commands in challenging real-life settings: oftentimes, ambient noise drowns the acoustic sound signals, and walls, face masks or other obstacles hide the mouth motion from optical sensors. To address these formidable challenges, an experimental prototype of a microwave speech recognizer empowered by programmable metasurface is presented here that can remotely recognize human voice commands and speaker identities even in noisy environments and if the speaker's mouth is hidden behind a wall or face mask. The programmable metasurface is the pivotal hardware ingredient of the system because its large aperture and huge number of degrees of freedom allows the system to perform a complex sequence of sensing tasks, orchestrated by artificial-intelligence tools. Relying solely on microwave data, the system avoids visual privacy infringements. The developed microwave speech recognizer can enable privacy-respecting voice-commanded human-machine interactions is experimentally demonstrated in many important but to-date inaccessible application scenarios. The presented strategy will unlock new possibilities and have expectations for future smart homes, ambient-assisted health monitoring, as well as intelligent surveillance and security.


Subject(s)
Microwaves , Speech Recognition Software , Humans
16.
Natl Sci Rev ; 11(3): nwad299, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38312383

ABSTRACT

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

17.
Light Sci Appl ; 13(1): 42, 2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38307847

ABSTRACT

Supercontinuum (SC) light source has advanced ultrafast laser spectroscopy in condensed matter science, biology, physics, and chemistry. Compared to the frequently used photonic crystal fibers and bulk materials, femtosecond laser filamentation in gases is damage-immune for supercontinuum generation. A bottleneck problem is the strong jitters from filament induced self-heating at kHz repetition rate level. We demonstrated stable kHz supercontinuum generation directly in air with multiple mJ level pulse energy. This was achieved by applying an external DC electric field to the air plasma filament. Beam pointing jitters of the 1 kHz air filament induced SC light were reduced by more than 2 fold. The stabilized high repetition rate laser filament offers the opportunity for stable intense SC generation and its applications in air.

18.
Adv Sci (Weinh) ; 11(11): e2303222, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38214384

ABSTRACT

The modern theory of quantized polarization has recently extended from 1D dipole moment to multipole moment, leading to the development from conventional topological insulators (TIs) to higher-order TIs, i.e., from the bulk polarization as primary topological index, to the fractional corner charge as secondary topological index. The authors here extend this development by theoretically discovering a higher-order end TI (HOETI) in a real projective lattice and experimentally verifying the prediction using topolectric circuits. A HOETI realizes a dipole-symmetry-protected phase in a higher-dimensional space (conventionally in one dimension), which manifests as 0D topologically protected end states and a fractional end charge. The discovered bulk-end correspondence reveals that the fractional end charge, which is proportional to the bulk topological invariant, can serve as a generic bulk probe of higher-order topology. The authors identify the HOETI experimentally by the presence of localized end states and a fractional end charge. The results demonstrate the existence of fractional charges in non-Euclidean manifolds and open new avenues for understanding the interplay between topological obstructions in real and momentum space.

19.
ACS Appl Mater Interfaces ; 16(4): 5234-5244, 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38241202

ABSTRACT

The electromagnetic (EM) beam manipulations such as spatial scanning have always been the focus in information science and technology. Generally, the transmitting and receiving (T/R) beams of the same aperture should be coincident due to the reciprocal theory, and hence, more flexible controls of the spatial information are limited accordingly. Here, we propose a new approach to achieve independent controls of beam scanning in spatial T/R channels based on one aperture made by a nonreciprocal programmable metasurface. The meta-atom is designed to have independent propagation chains for T/R waves by introducing dual-direction power amplifiers (PAs) as the isolators for one-way transparency. A programmable phase shifter with a 360° coverage is loaded with the PA device in the transmitting or receiving chain to realize independent beam scanning in the T/R channels. A prototype of the proposed metasurface is fabricated, and independent beam scanning in the T/R channels is directly acquired with good performance in our measurements. In addition, a proof of concept of integrated sensing and auxiliary communications is accomplished to verify the validity of the presented method.

20.
Adv Sci (Weinh) ; 11(7): e2306181, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38064159

ABSTRACT

Due to its ability to adapt to a variety of electromagnetic (EM) environments, the sensing-enabled metasurface has garnered significant attention. However, large-scale EM-field sensing to obtain more information is still very challenging. Here, an adaptive information metasurface is proposed to enable intelligent sensing and wave manipulating simultaneously or more specifically, to realize intelligent target localization and beam tracking adaptively. The metasurface is composed of an array of meta-atoms, and each is loaded with two PIN diodes and a sensing-channel structure, for polarization-insensitive and programmable beamforming and sensing. By controlling the state of the PIN diode, the proposed meta-atom has 1-bit phase response in the designed frequency band, while the sensing loss keeps higher than -10 dB for both "ON" and "OFF" states. Hence there is nearly no interaction between the beamforming and sensing modes. Experiments are conducted to show multiple functions of the metasurface, including intelligent target sensing and self-adaptive beamforming, and the measured results are in good agreement with the numerical simulations and theoretical calculations.

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