N6-methyldeoxyadenosine marks active transcription start sites in Chlamydomonas.

N(6)-methyldeoxyadenosine (6mA or m(6)A) is a DNA modification preserved in prokaryotes to eukaryotes. It is widespread in bacteria and functions in DNA mismatch repair, chromosome segregation, and virulence regulation. In contrast, the distribution and function of 6mA in eukaryotes have been unclear. Here, we present a comprehensive analysis of the 6mA landscape in the genome of Chlamydomonas using new sequencing approaches. We identified the 6mA modification in 84% of genes in Chlamydomonas. We found that 6mA mainly locates at ApT dinucleotides around transcription start sites (TSS) with a bimodal distribution and appears to mark active genes. A periodic pattern of 6mA deposition was also observed at base resolution, which is associated with nucleosome distribution near the TSS, suggesting a possible role in nucleosome positioning. The new genome-wide mapping of 6mA and its unique distribution in the Chlamydomonas genome suggest potential regulatory roles of 6mA in gene expression in eukaryotic organisms.

Programming and inheritance of parental DNA methylomes in mammals.

The reprogramming of parental methylomes is essential for embryonic development. In mammals, paternal 5-methylcytosines (5mCs) have been proposed to be actively converted to oxidized bases. These paternal oxidized bases and maternal 5mCs are believed to be passively diluted by cell divisions. By generating single-base resolution, allele-specific DNA methylomes from mouse gametes, early embryos, and primordial germ cell (PGC), as well as single-base-resolution maps of oxidized cytosine bases for early embryos, we report the existence of 5hmC and 5fC in both maternal and paternal genomes and find that 5mC or its oxidized derivatives, at the majority of demethylated CpGs, are converted to unmodified cytosines independent of passive dilution from gametes to four-cell embryos. Therefore, we conclude that paternal methylome and at least a significant proportion of maternal methylome go through active demethylation during embryonic development. Additionally, all the known imprinting control regions (ICRs) were classified into germ-line or somatic ICRs.

Discovery of a Bacterial Hydrazine Transferase That Constructs the N-Aminolactam Pharmacophore in Albofungin Biosynthesis.

Structural motifs containing nitrogen-nitrogen (N-N) bonds are prevalent in a large number of clinical drugs and bioactive natural products. Hydrazine (N2H4) serves as a widely utilized building block for the preparation of these N-N-containing molecules in organic synthesis. Despite its common use in chemical processes, no enzyme has been identified to catalyze the incorporation of free hydrazine in natural product biosynthesis. Here, we report that a hydrazine transferase catalyzes the condensation of N2H4 and an aromatic polyketide pathway intermediate, leading to the formation of a rare N-aminolactam pharmacophore in the biosynthesis of broad-spectrum antibiotic albofungin. These results expand the current knowledge on the biosynthetic mechanism for natural products with N-N units and should facilitate future development of biocatalysts for the production of N-N-containing chemicals.

Serum hepatitis B virus spliced RNA proportion increases with liver disease progression in patients with chronic hepatitis B.

Serum hepatitis B virus (HBV) spliced RNAs (spRNAs) are ubiquitous in HBV-infected patients; however, their clinical significance remains unknown. Therefore, we aimed to explore the relationship between HBV spRNAs and liver disease progression in chronic hepatitis B (CHB) patients; in vitro cell line assessment was also performed. The serum HBV wild-type RNA (wtRNA) and spRNA levels were individually quantified in a cohort of 279 treatment-naïve, hepatitis B e antigen positive CHB patients with or without cirrhosis. The spRNA proportion was determined as (spRNA × 100%)/(spRNAs + wtRNA). 20 patients' serum samples underwent spRNA species profiling using next-generation sequencing. Serum spRNA species 1, 2, 3, 4, and 5 were the most common variants. The spRNA proportion varied from 0.00% to 19.02%, with higher levels in HBV genotype C patients than in those with genotype B (1.76% vs. 0.84%, p < 0.001). The spRNA proportion was positively associated with the alanine aminotransferase levels (r = 0.144, p = 0.053) and significantly higher in cirrhotic than in non-cirrhotic patients (1.69% vs. 1.04%, p = 0.001). Multivariate analysis revealed a 2.566-fold higher risk of cirrhosis in patients with elevated spRNA proportion (p = 0.024). In vitro experiments confirmed that spRNAs contributed to hepatic stellate cell activation, which is critical in liver fibrosis development. Therefore, increased HBV spRNA expression poses a risk for liver disease progression. Quantifying serum HBV spRNAs can aid in monitoring liver disease progression. Furthermore, the therapeutic targeting of spRNAs may improve the prognosis of patients with CHB.

Discrete wavelet transform assisted convolutional neural network equalizer for PAM VLC system.

With the deepening of research and the further differentiation of damage types, and to compensate for both linear and nonlinear damage in visible light communication systems (VLCs), we propose a novel discrete wavelet transform-assisted convolutional neural network (DWTCNN) equalizer that combines the advantages of wavelet transform and deep learning methods. More specifically, wavelet transform is used in DWTCNN to decompose the signal into diverse coefficient series and employ an adaptive soft-threshold method to eliminate redundant information in the signal. The coefficients are then reconstructed to achieve complete signal compensation. The experimental results show that the proposed DWTCNN equalizer can significantly reduce nonlinear impairment and improve system performance with the bit error rate (BER) under the 7% hard-decision forward error correction (HD-FEC) limit of 3.8 × 10-3. We also experimentally compared DWTCNN with the Long Short-Term Memory (LSTM) and entity extraction neural network (EXNN) equalizer, the Q factor has been improved by 0.76 and 0.53 dB, and the operating ranges of the direct current (DC) bias have increased by 4.76% and 23.5%, respectively.

A Highly Sensitive and Robust Method for Genome-wide 5hmC Profiling of Rare Cell Populations.

We present a highly sensitive and selective chemical labeling and capture approach for genome-wide profiling of 5-hydroxylmethylcytosine (5hmC) using DNA isolated from ∼1,000 cells (nano-hmC-Seal). Using this technology, we assessed 5hmC occupancy and dynamics across different stages of hematopoietic differentiation. Nano-hmC-Seal profiling of purified Tet2-mutant acute myeloid leukemia (AML) murine stem cells allowed us to identify leukemia-specific, differentially hydroxymethylated regions that harbor known and candidate disease-specific target genes with differential 5hmC peaks compared to normal stem cells. The change of 5hmC patterns in AML strongly correlates with differential gene expression, demonstrating the importance of dynamic alterations of 5hmC in regulating transcription in AML. Together, covalent 5hmC labeling offers an effective approach to study and detect DNA methylation dynamics in in vivo disease models and in limited clinical samples.

In Situ Test and Numerical Analysis of the Subway-Induced Vibration Influence in Historical and Cultural Reserves.

Although the rapid expansion of urban rail transit offers convenience to citizens, the issue of subway vibration cannot be overlooked. This study investigates the spatial distribution characteristics of vibration in the Fayuan Temple historic and cultural reserve. It involves using a V001 magnetoelectric acceleration sensor capable of monitoring low amplitudes with a sensitivity of 0.298 V/(m/s2), a measuring range of up to 20 m/s2, and a frequency range span from 0.5 to 100 Hz for in situ testing, analyzing the law of vibration propagation in this area, evaluating the impact on buildings, and determining the vibration reduction scheme. The reserve is divided into three zones based on the vertical vibration level measured during the in situ test as follows: severely excessive, generally excessive, and non-excessive vibration. Furthermore, the research develops a dynamic coupling model of vehicle-track-tunnel-stratum-structure to verify the damping effect of the wire spring floating plate track and periodic pile row. It compares the characteristics of three vibration reduction schemes, namely, internal vibration reduction reconstruction, periodic pile row, and anti-vibration reinforcement or reconstruction of buildings, proposing a comprehensive solution. Considering the construction conditions, difficulty, cost, and other factors, a periodic pile row is recommended as the primary treatment measure. If necessary, anti-vibration reinforcement or reconstruction of buildings can serve as supplemental measures.

A Sparse Recovery Algorithm for Suppressing Multiple Linear Frequency Modulation Interference in the Synthetic Aperture Radar Image Domain.

In synthetic aperture radar (SAR) signal processing, compared with the raw data of level-0, level-1 SAR images are more readily accessible and available in larger quantities. However, an amount of level-1 images are affected by radio frequency interference (RFI), which typically originates from Linear Frequency Modulation (LFM) signals emitted by ground-based radars. Existing research on interference suppression in level-1 data has primarily focused on two methods: transforming SAR images into simulated echo data for interference suppression, or focusing interference in the frequency domain and applying notching filters to reduce interference energy. However, these methods overlook the effective utilization of the interference parameters or are confined to suppressing only one type of LFM interference at a time. In certain SAR images, multiple types of LFM interference manifest bright radiation artifacts that exhibit varying lengths along the range direction while remaining constant in the azimuth direction. It is necessary to suppress multiple LFM interference on SAR images when original echo data are unavailable. This article proposes a joint sparse recovery algorithm for interference suppression in the SAR image domain. In the SAR image domain, two-dimensional LFM interference typically exhibits differences in parameters such as frequency modulation rate and pulse width in the range direction, while maintaining consistency in the azimuth direction. Based on this observation, this article constructs a series of focusing operators for LFM interference in SAR images. These operators enable the sparse representation of dispersed LFM interference. Subsequently, an optimization model is developed that can effectively suppress multi-LFM interference and reduce image loss with the assistance of a regularization term in the image domain. Simulation experiments conducted in various scenarios validate the superior performance of the proposed method.

Spatial distribution, contamination characteristics and ecological-health risk assessment of toxic heavy metals in soils near a smelting area.

Soil heavy metals (HMs) contamination stemming from smelting and mining activities is becoming a global concern due to its devastating impacts on the environment and human health. In this study, 128 soil samples were investigated to assess the spatial distribution, contamination characteristics, ecological and human health risk of HMs in soils near a smelting area by using BP artificial neural network (BP-ANN) and Monte Carlo simulation. The results showed that the concentrations of all five HMs in the soil greatly exceeded the background value of study area with a basic trend: Pb > As > Cr > Cd > Hg, indicating a high pollution level. Arsenic and lead were the major pollutants in the study area with an exceedance rate of 78.95% and 28.95%, respectively. The toxic fume and dust emitted during the smelting process were identified as the major sources of HMs pollution in soil, while Cd pollution was mainly caused by agricultural activities near the study area. The probabilistic risk assessment suggested that the average HQ values of five HMs for children and adults exceeded the acceptable threshold with a trend: As > Pb > Cr > Cd > Hg. The average CR values of As, Cr and Pb for all population were greatly larger than the acceptable threshold (CR ≥ 1), indicating a high cancer risk. However, the CR values of Cd for adults and children were within the acceptable threshold (CR < 1), implying no cancer risk. The results of the present study can provide some insight into the contamination characteristics, ecological and human health risk of HMs in contaminated soils by mining and smelting activities, which can help prevent and control soil pollution and environmental risk.

CircSOD2 Contributes to Tumor Progression, Immune Evasion and Anti-PD-1 Resistance in Hepatocellular Carcinoma by Targeting miR-497-5p/ANXA11 Axis.

Circular RNAs (circRNAs) can function as functional molecules in hepatocellular carcinoma (HCC). Herein, circRNA superoxide dismutase 2 (circSOD2) was researched in HCC progression and immune system. The real-time polymerase chain reaction (qRT-PCR) was used for quantification of circSOD2, microRNA-497-5p (miR-497-5p) and Annexin A11 (ANXA11). Cell assays were performed by 3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyl tetrazolium bromide (MTT) and colony formation assays for proliferation, flow cytometry for apoptosis and cell cycle, wound healing assay for migration and transwell assay for migration/invasion. ANXA11 and metastatic protein levels were measured by western blot. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to analyze target binding. CD8+ T cell immunity was assessed by Immunohistochemistry (IHC) assay, and the effect of circSOD2 on programmed cell death 1 (PD-1) immune checkpoint inhibitors (anti-PD-1) therapy was evaluated by mice xenograft assay. CircSOD2 was upregulated in HCC tissues and cells. Knockdown of circSOD2 resulted in HCC cell growth inhibition, apoptosis promotion, cell cycle arrest and metastasis suppression. Mechanically, circSOD2 promoted HCC development by acting as a miR-497-5p sponge and miR-497-5p played a tumor-inhibitory role in HCC cells by targeting ANXA11. Moreover, circSOD2 induced upregulation of ANXA11 expression by interacting with miR-497-5p. Also, the promoting effects of circSOD2 on immune evasion and anti-PD-1 resistance were related to miR-497-5p/ANXA11 axis. This study elucidated the pivotal function of circSOD2 in HCC progression and immunosuppression by mediating miR-497-6p/ANXA11 axis. CircSOD2/miR-497-5p/ANXA11 axis was a novel view of circRNA research in HCC.

Real Aperture Radar Super-Resolution Imaging for Sea Surface Monitoring Based on a Hybrid Model.

In recent years, super-resolution imaging techniques have been intensely introduced to enhance the azimuth resolution of real aperture scanning radar (RASR). However, there is a paucity of research on the subject of sea surface imaging with small incident angles for complex scenarios. This research endeavors to explore super-resolution imaging for sea surface monitoring, with a specific emphasis on grounded or shipborne platforms. To tackle the inescapable interference of sea clutter, it was segregated from the imaging objects and was modeled alongside I/Q channel noise within the maximum likelihood framework, thus mitigating clutter's impact. Simultaneously, for characterizing the non-stationary regions of the monitoring scene, we harnessed the Markov random field (MRF) model for its two-dimensional (2D) spatial representational capacity, augmented by a quadratic term to bolster outlier resilience. Subsequently, the maximum a posteriori (MAP) criterion was employed to unite the ML function with the statistical model regarding imaging scene. This hybrid model forms the core of our super-resolution methodology. Finally, a fast iterative threshold shrinkage method was applied to solve this objective function, yielding stable estimates of the monitored scene. Through the validation of simulation and real data experiments, the superiority of the proposed approach in recovering the monitoring scenes and clutter suppression has been verified.

Inorganic-Organic Hybrid Phototransistor Array with Enhanced Photogating Effect for Dynamic Near-Infrared Light Sensing and Image Preprocessing.

Narrow-band-gap organic semiconductors have emerged as appealing near-infrared (NIR) sensing materials by virtue of their unique optoelectronic properties. However, their limited carrier mobility impedes the implementation of large-area, dynamic NIR sensor arrays. In this work, high-performance inorganic-organic hybrid phototransistor arrays are achieved for NIR sensing, by taking advantage of the high electron mobility of In2O3 and the strong NIR absorption of a BTPV-4F:PTB7-Th bulk heterojunction (BHJ) with an enhanced photogating effect. As a result, the hybrid phototransistors reach a high responsivity of 1393.0 A W-1, a high specific detectivity of 4.8 × 1012 jones, and a fast response of 0.72 ms to NIR light (900 nm). Meanwhile, an integrated 16 × 16 phototransistor array with a one-transistor-one-phototransistor (1T1PT) architecture is achieved. On the basis of the enhanced photogating effect, the phototransistor array can not only achieve real-time, dynamic NIR light mapping but also implement image preprocessing, which is promising for advanced NIR image sensors.

A Quantitative Approach to Determine Hydrophobe Content of Associating Polyacrylamide Using a Fluorescent Probe.

Hydrophobically associating polymers have found widespread applications in many domains due to their unique rheological behavior, which is primarily dictated by the hydrophobe content. However, the low fraction of hydrophobic monomers in polymers makes this parameter's precise and straightforward measurement difficult. Herein, a variety of hydrophobically associating polyacrylamides (HAPAM) with different alkyl chain lengths (L) and hydrophobic contents ([H]) were prepared by post-modification and accurately characterized by 1H NMR spectroscopy. The maximal fluorescence emission intensity (I) of 8-anilino-1-naphthalenesulfonic acid, which is sensitive to hydrophobic environments, was then detected in those polymer solutions and shown as a ratio to that in the polymer-free solution (I0). It was found that I/I0 for 0.5 wt% HAPAM can be scaled versus CH, which is a variate related to both L and [H], as I/I0 = 1.15 + 1.09 × 108CH3.42, which was also verified to be applicable for hydrophobic associating hydrolyzed polyacrylamide (HHAPAM). This relationship provides a handy method for determining the hydrophobic content of hydrophobically associating polymers, particularly for field applications.

Association of Serum Hepatitis B Virus RNA With Hepatocellular Carcinoma Risk in Chronic Hepatitis B Patients Under Nucleos(t)ide Analogues Therapy.

BACKGROUND: Whether serum hepatitis B virus (HBV) RNA associates with hepatocellular carcinoma (HCC) development in chronic hepatitis B (CHB) patients has not been fully elucidated. METHODS: We enrolled 2974 patients receiving nucleos(t)ide analogues (NAs) from a prospective, observational CHB cohort to investigate the effect of serum HBV RNA, measured at study entry (baseline), on HCC development, using Cox regression analyses. RESULTS: During median follow-up of 4.4 years, 90 patients developed HCC. Patients with detectable baseline HBV RNA (n = 2072) exhibited significantly higher HCC risk than those with undetectable level (5-year HCC incidence estimated by Kaplan-Meier method: 4.1% versus 1.8%, P = .009; adjusted hazard ratio [aHR] = 2.21, P = .005). HBV RNA levels of 609-99 999 and ≥100 000 copies/mL were associated with incrementally increasing HCC risk (aHR = 2.15 and 3.05, respectively; P for trend = .003), compared to undetectable level (<609 copies/mL). Moreover, patients with single-detectable either HBV DNA or RNA and double-detectable DNA and RNA had 1.57- and 4.02-fold higher HCC risk, respectively, than those with double-undetectable DNA and RNA (P for trend = .001). CONCLUSIONS: High-level HBV RNA is associated with increased HCC risk in NAs-treated patients. Achieving undetectable HBV RNA may contribute to better clinical outcomes, indicating it could be a valuable endpoint of anti-HBV treatment.

An Iridium-Stabilized Borenium Intermediate.

Exploration of new organometallic systems based on polyhedral boron clusters has the potential to solve challenging chemical problems such as the stabilization of reactive intermediates and transition-state-like species postulated for E-H (E = H, B, C, Si) bond activation reactions. We report on facile and clean B-H activation of a hydroborane by a new iridium boron cluster complex. The product of this reaction is an unprecedented and fully characterized transition metal-stabilized boron cation or borenium. Moreover, this intermediate bears an unusual intramolecular B···H interaction between the hydrogen originating from the activated hydroborane and the cyclometallated metal-bonded boron atom of the boron cluster. This B···H interaction is proposed to be an arrested insertion of hydrogen into the Bcage-metal bond and the initiation step for iridium "cage-walking" around the upper surface of the boron cluster. The "cage-walking" process is supported by the hydrogen-deuterium exchange observed at the boron cluster, and a mechanism is proposed on the basis of theoretical methods with a special focus on the role of noncovalent interactions. All new compounds were isolated and fully characterized by NMR spectroscopy and elemental analysis. Key compounds were studied by single crystal X-ray diffraction and X-ray photoelectron spectroscopy.

Non-Destructive Extraction and Separation of Nano- and Microplastics from Environmental Samples by Density Gradient Ultracentrifugation.

Nano-/microplastics (NMPs, particle diameter < 5 mm) are widespread emerging pollutants causing diverse impacts on organisms due to their sizes, shapes, and chemical properties. Despite the fast increase in NMP research, an effective method to separate and identify NMP types from environmental samples is still lacking. Here, we developed a simple and effective approach for the non-destructive extraction and separation of various types of NMPs from environmental samples by density gradient ultracentrifugation (DGU). For the first time, DGU was capable to separate various NMPs from the complex matrix with high selectivity (100%), purity (93%), and applicability. Through a gradually changing density of the density gradient medium by changing the concentrations or volumes of CsCl/water solution (from 0.00065 to 0.01989 g cm-3 mm-1), various NMPs (with particle sizes as little as 50 nm) could be extracted and separated from soil samples with high recovery (78.5-96.0%). We confirmed the effectiveness and compatibility of DGU through a correct identification of all types of NMPs separated from artificial soil samples with Raman spectroscopy, simultaneous thermal analysis (STA), and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). DGU is compatible with all analytical processes compared to other existing methods with much less sample pretreatment time (0.5 h). Overall, DGU is an effective and cheap method (2.2 USD/sample) to separate NMPs from environmental samples such as soil and water and, hence, can facilitate research on NMPs related to terrestrial and marine environments as well as human health.

Controllable Fabrication of PdO-PdAu Ternary Hollow Shells: Synergistic Acceleration of H2 -Sensing Speed via Morphology Regulation and Electronic Structure Modulation.

Designing ultrafast H2 sensors is of particular importance for practical applications of hydrogen energy but still quite challenging. Herein, PdO decorated PdAu ternary hollow shells (PdO-PdAu HSs) exhibiting an ultrafast response of ≈0.9 s to 1% H2 in air at room temperature are presented. PdO-PdAu HSs are fabricated by calcinating PdAu bimetallic HSs in air to form PdO-Au binary HSs, which are then partially reduced by NaBH4 solution, forming PdO-PdAu HSs. This ternary hybrid material takes advantage of multiple aspects to synergistically accelerate the sensing speed. The HS morphology promises high gas accessibility and high surface area for H2 adsorption, and decoration of Au and PdO alters the electronic state of Pd and reduces the energy barrier for hydrogen diffusing from the surface site of Pd into the subsurface site. The content of Au and PdO in the ternary HSs can be simply tuned, which offers the possibility to optimize their promotion effects to reach the best performance. The proposed fabrication strategy sheds light on the rational design of ultrafast Pd-based H2 sensors by controlling the sensor structure and engineering the electronic state of active species.

Highly Linear and Symmetric Synaptic Memtransistors Based on Polarization Switching in Two-Dimensional Ferroelectric Semiconductors.

Brain-inspired neuromorphic computing hardware based on artificial synapses offers efficient solutions to perform computational tasks. However, the nonlinearity and asymmetry of synaptic weight updates in reported artificial synapses have impeded achieving high accuracy in neural networks. Here, this work develops a synaptic memtransistor based on polarization switching in a two-dimensional (2D) ferroelectric semiconductor (FES) of α-In2 Se3 for neuromorphic computing. The α-In2 Se3 memtransistor exhibits outstanding synaptic characteristics, including near-ideal linearity and symmetry and a large number of programmable conductance states, by taking the advantages of both memtransistor configuration and electrically configurable polarization states in the FES channel. As a result, the α-In2 Se3 memtransistor-type synapse reaches high accuracy of 97.76% for digit patterns recognition task in simulated artificial neural networks. This work opens new opportunities for using multiterminal FES memtransistors in advanced neuromorphic electronics.

TRPM2 regulates autophagy to participate in hepatitis B virus replication.

Hepatitis B virus (HBV) affects over 300 million people across the world and is further associated with the self-digesting process of autophagy. Accordingly, the current study set out to explore the role of transient receptor potential cation channel subfamily M member 2 (TRPM2) in HBV replication. Firstly, Huh-7 cells were transfected with the pHBV1.3 plasmid to detect the expression patterns of TRPM2 and neutrophil cytosolic factor 1 (p47 phox), followed by evaluating the role of TRPM2 in autophagy and HBV replication and exploring the interaction between TRPM2 and p47 phox. Collaborative experiments were further designed to explore the role of p47 phox and autophagy in TRPM2 regulation of HBV replication, in addition to animal experimentation to validate the role of TRPM2/p47 phox axis in vivo. It was found that TRPM2 up-regulation was associated with HBV replication. On the other hand, silencing of TRPM2 inhibited HBV replication and autophagy in vitro and in vivo, as evidenced by reduced HBV DNA load, HBV mRNA, HBeAg and HBsAg, and diminished autophagic spot number, LC3 II/I ratio, Beclin-1 expressions and increased p62 expressions. Mechanistic experimentation illustrated that TRPM2 interacted with p47 phox and positively regulated p47 phox, such that p47 phox up-regulation or use of Rapamycin (autophagy activator) weakened the inhibitory role of silencing TRPM2. Collectively, our findings indicated that HBV infection promotes TRPM2 expression, and TRPM2 interacts with p47 phox to induce autophagy and facilitate HVB replication.

Utilizing deep neural networks to extract non-linearity as entities in PAM visible light communication with noise.

Herein, we propose a novel entity extraction neural network (EXNN) with a newly designed sampling convolution kernel approach and a deep learning-based structure to differentiate noise in visible light communication (VLC) systems. In particular, EXNN is used to extract linear and nonlinear distortion in a received signal as an entity and compensate for the signal by removing it. First, we designed a deep learning structure tailored for VLC systems, used experimentation to validate our algorithm's usability, and determined an appropriate range for the hyper-parameters that govern the PAM-8 system. Second, we compared our approach with existing finite impulse response (FIR) linear and Volterra nonlinear compensation algorithms via experiments. Below the hard-decision forward error correction (HD-FEC) threshold limit of 3.8×10-3, experimental results show that the use of the EXNN increased the operating range of the direct current (DC) bias and the voltage by ∼33.3% and by ∼50% under optimal conditions, respectively. Furthermore, under corresponding optimal power conditions, the proposed approach improved the Q factor of the VLC system by 0.36 and 1.57 dB compared with the aforementioned linear and nonlinear equalizers, respectively. To the best of our knowledge, this is the first time that a deep learning operator has been custom-designed for the VLC system and we have named the completely redesigned network with this sampling convolution kernel operator as EXNN.