Search

Background:: A drug-eluting stent (DES) is a highly beneficial medical device used to widen or unblock narrowed blood vessels. However, the drugs released by the implantation of DES may hinder the re-endothelialization process, increasing the risk of late thrombosis. We have developed a tacrolimus-eluting stent (TES) that as acts as a potent antiproliferative and immunosuppressive agent, enhancing endothelial regeneration. In addition, we assessed the safety and efficacy of TES through both in vitroand in vivotests. Methods:: Tacrolimus and Poly(lactic-co-glycolic acid) (PLGA) were applied to the metal stent using electrospinning equipment. The surface morphology of the stent was examined before and after coating using a scanning electron microscope (SEM) and energy dispersive X-rays (EDX). The drug release test was conducted through high-performance liquid chromatography (HPLC). Cell proliferation and migration assays were performed using smooth muscle cells (SMC). The stent was then inserted into the porcine coronary artery and monitored for a duration of 4 weeks. Results:: SEM analysis confirmed that the coating surface was uniform. Furthermore, EDX analysis showed that the surface was coated with both polymer and drug components. The HPCL analysis of TCL at a wavelength of 215 nm revealed that the drug was continuously released over a period of 4 weeks. Smooth muscle cell migration was significantly decreased in the tacrolimus group (54.1% ± 11.90%) compared to the non-treated group (90.1% ± 4.86%). In animal experiments, the stenosis rate was significantly reduced in the TES group (29.6% ± 7.93%) compared to the bare metal stent group (41.3% ± 10.18%). Additionally, the fibrin score was found to be lower in the TES group compared to the group treated with a sirolimus-eluting stent (SES). Conclusion:: Similar to SES, TES reduces neointimal proliferation in a porcine coronary artery model, specifically decreasing the fibrins score. Therefore, tacrolimus could be considered a promising drug for reducing restenosis and thrombosis.

Female urethral diverticulum (UD), an evagination of the urethral mucosa into the surrounding connective tissue, is extremely rare in pregnancy. No clear guidelines on the optimal management of UD have been established, except for a common conservative approach. Here, we discuss how to manage UD with pregnancy.

Pyrolysis-based plastic chemical recycling has gained significant industrial attention due to its advantage of eliminating complex plastic sorting processes. However, plastic pyrolysis oil contains various components that require stringent removal before subsequent processes. In particular, Cl compounds originating from the decomposition of poly(vinyl chloride) can cause serious corrosion of reactors and catalyst deactivation in downstream processes. While extensive research has been conducted on the removal of other heteroatoms (S, N, and O) from organic compounds via hydrotreating, studies on the removal of Cl have been scarce. In this study, hydrodechlorination over Pt catalysts on various supports is comprehensively investigated using 1,2-dichloroethane as a model reactant. Our results demonstrate that Pt on γ-Al2O3can exhibit exceptionally high catalytic activity compared to those on other supports due to a distinct bifunctional mechanism. Rigorous studies reveal that the Lewis acidic pentacoordinated Al sites of γ-Al2O3activate C–Cl bonds, whereas Pt activates H2and provides spillover H to remove Cl as HCl. The bifunctional mechanism enables the minimized use of precious Pt (<0.1 wt %) to achieve high activity. Pt/γ-Al2O3also allows for efficient Cl removal (96.8%) with high stability in treating waste plastic pyrolysis oil containing 7500 ppm of Cl.

Graphene has been extensively investigated as a host material for Li metal anodes owing to its light weight, high electrical conductivity, high surface area, and exceptional mechanical rigidity. Many studies have focused on assembling two-dimensional (2D) graphene sheets into three-dimensional (3D) forms, such as lamination, spheres, and carbon nanotubes; however, little attention has been paid to the technology of modifying 2D graphene sheets. Herein, nanoperforated graphene (NPG) was fabricated through a relatively straightforward process employing metal oxide catalysts based on aqueous solutions. Nanoperforations exhibited a size of approximately 5 nm and were introduced on the graphene sheet and lithiophilic carbonyl groups (C = O) at the edges, facilitating the rapid diffusion of Li+and lowering the Li nucleation overpotential. In comparison to the reduced graphene oxide (RGO) host, the NPG host exhibited a lower lithium nucleation overpotential and a stable overpotential of ~ 30 mV for over 150 cycles as a stable host structure as a Li metal anode for Li metal batteries.

The fibrous tubular scaffold (FTS) has potential as a vascular graft; however, its clinical application is hindered by insufficient mechanical properties. Inadequate mechanical properties of vascular grafts can lead to some serious side effects such as intimal hyperplasia, luminal expansion, and blood thrombogenicity. In this study, we developed a novel fibrous tubular scaffold comprising multiscale fibers to ensure superior mechanical properties. Our novel approach involves a one-step manufacturing method that can fabricate the superflexible fibrous tubular scaffold (SF-FTS) with topographical features via a modified electrospinning setup. We investigated the effect of humidity and temperature during the fabrication process on the formation of multiscale fibers. It was demonstrated that the incorporation of multiscale fibers and topographical features significantly enhances the mechanical properties of FTS. The mechanical advantages of SF-FTS were confirmed through the kinking resistance test, compressive test, and in vivo experiments. Additionally, we explored the interaction between the multiscale fibers and human umbilical vein endothelial cells (HUVECs) behavior. Our results suggest a novel strategy for fabricating FTS with advanced mechanical properties, and the designed SF-FTS holds promise as a potential candidate for clinical applications.

Echinacea purpurea(L.), a member of Asteraceaefamily, has traditionally been used in numerous countries to treat and prevent various immune-related diseases. This study confirmed the oral toxicity and genotoxicity profile of standardized E. purpureaextract under good laboratory practice (GLP) conditions and the pharmacokinetic features of chicoric acid, a major ingredient in E. purpureaextract. For the repeated-dose toxicity test, Sprague Dawley (SD) rats were orally administered 500, 1000, and 2000 mg/kg/day of E. purpureaextract continuously for 13 weeks. The genotoxicity of E. purpureawas determined using standard genotoxicity tests, including bacterial reverse mutations, chromosome aberrations, and micronucleus tests. Additionally, a validated LC–MS/MS method was employed to measure chicoric acid levels in rat plasma for pharmacokinetic analysis. The results of this study indicate that during repeated oral administration of E. purpurea, both male and female SD rats showed no abnormal clinical signs. Furthermore, the genotoxicity tests did not reveal any evidence of genotoxicity in E. purpurea. Pharmacokinetic profile of chicoric acid, following the oral administration of highly purified chicoric acid (95%) and standardized E. purpureaextracts containing 2% chicoric acid, revealed the oral bioavailability to be approximately 1.5%. Increasing the dose of standardized E. purpureaextract (equivalent to 20–100 mg/kg of chicoric acid) from 1 to 5 g/kg resulted in a proportional increase in systemic exposure without reaching saturation. In this study, E.purpureadid not cause oral toxicity and genotoxicity. Additionally, the crude formulation was found to have minimal impact on the pharmacokinetics of chicoric acid.

[Display omitted] 3D spheroids are used as a therapeutic strategy and transplanted in vivo owing to their ability to better mimic the microphysiological environment that is crucial for the transplants to be able to engraft and vascularize for their long-term survival and functionalization in the host tissue. Among various methods of fabricating spheroids, the utilization of magnetic force enables rapid cell aggregation and spatial regulation. Encapsulating a magnetic spheroid with endothelial cells paves the way toward vascularization. Here, we magnetically bioprinted vascular assembly by coating magnetic spheroids with the magnetic nanoparticles (MNPs)-internalized vascular endothelial cells. MNPs-internalized mouse myoblasts cells (C2C12) were magnetically aggregated by placing a neodymium magnet under a well plate and then encapsulated by MNPs-internalized human umbilical vein endothelial cells (HUVECs). Internalization of MNPs did not hinder cell viability and vascularization-related gene expression, and the transplant of the vascular assemblies could sprout and be engrafted into the host tissue within three days. As these vascular assemblies are easily fabricated by coating spheroids with MNPs-internalized endothelial cells and controlled by a magnetic force, they may be used for engraftment and vascularization in various applications with spheroids with different functions. [ABSTRACT FROM AUTHOR]

Abstract:In this essay, I suggest Sir Thomas Browne as a new religious and medical author of influence. Based on a radical perspective of the anatomy of the human soul, he emphasizes the importance of a rational faith to fulfill the demand of reason and to create a Reformative social milieu in defense of cultural Christianity. In a situation where there is a geographic turn in religious studies and a religious turn in literary studies, I redefine Sir Thomas Browne’s geography of religion as an environment where God’s love, including the human practice of charity, unfolds for Christian tolerance and reconciliation.

Oil pollution in the ocean is becoming more and more of a serious issue, which increases interest in both ways for combating its cause and methods for observing and monitoring how oil spreads. A promising approach based on an optical method with empirical relations for selected viscous oil–water systems is presented. Based on a modified melamine sponge (MMS), the microscopic spreading and oil capillary penetration phenomenon of the porous structure were investigated. The objective of this study is 2-fold: (i) to present a more thorough experimental description of the spreading of viscous oil lens on the water surface and capillary action of oil lens into MMS porous structure; and (ii) to provide a theoretical description that helps to explain some of the observed behavior. With knowledge of δ∞2=−2SρW/gρO(ρW−ρO), we can determine the spreading coefficient S. It needs to be pointed out that the oil lens floating on the water surface does satisfy Neumann’s rule as the spreading coefficient of the air–oil–water system is negative (− 9.8 mN/m), indicating the ability to form a stable oil lens with thickness δO= 3.04 mm and radius RL= 38.64 mm after 60 min of spreading test. Furthermore, to better understand the capillary phenomena from a mechanical approach, an oil lens in contact with the surface of the MMS porous structure, by in-depth visualization, is properly defined as the balance of forces acting. Finally, as an illustration of this method, we utilized this approach to obtain the equilibrium height of the capillary rise and take it into account in terms of effective material thickness.

Metal-halide perovskites have garnered considerable research attention as highly efficient light emitters in recent years due to their outstanding optoelectronic properties with remarkable tunability and excellent solution processabilities. Substantial advancements have been achieved in the development of novel halide perovskites, and the exploitations of these materials in light-emitting devices. This review comprehensively outlines recent breakthroughs in metal-halide perovskites, encompassing the rational design of perovskite materials with tunable light emission properties, the controllable growth of single crystal for a deeper understanding of their structure–property relationships, as well as the fundamental insights into the photophysics and carrier dynamics in perovskite systems. Additionally, it provides an overview of recent applications of perovskite materials in high-performance light-emitting diodes (LEDs) and lasers.

Polyphenols have been investigated for their potential to mitigate inflammation in the context of atopic dermatitis (AD). In this study, epigallocatechin-3-gallate (EGCG)-based carbon dots (EGCG@CDs) were developed to enhance transdermal penetration, reduce inflammation, recapitulate superoxide dismutase (SOD) activity, and provide antimicrobial effects for AD treatment. The water-soluble EGCG@CDs in a few nanometers size exhibit a negative zeta potential, making them suitable for effective transdermal penetration. The fluorescence properties, including an upconversion effect, make EGCG@CDs suitable imaging probes for both in vitroand in vivoapplications. By mimicking the SOD enzyme, EGCG@CDs scavenge reactive oxygen species (ROS) and actively produce hydrogen peroxide through a highly catalytic capability toward the oxygen reduction reaction, resulting in the inhibition of bacterial growth. The enhanced antioxidant properties, high charge mobility, and various functional groups of EGCG@CDs prove effective in reducing intracellular ROS in an in vitroAD model. In the mouse AD model, EGCG@CDs incorporated into a hydrogel actively penetrated the epidermal layer, leading to ROS scavenging, reduced mast cell activation, and histological recovery of skin barriers. This research represents the versatile potential of EGCG@CDs in addressing AD and advancing tissue engineering.

Mutualistic interactions between marine phototrophs and associated bacteria are an important strategy for their successful survival in the ocean, but little is known about their metabolic relationships. Here, bacterial communities in the algal sphere (AS) and bulk solution (BS) of nine marine red algal cultures were analyzed, and Roseibiumand Phycisphaerawere identified significantly more abundantly in AS than in BS. The metabolic features of RoseibiumRMAR6-6 (isolated and genome-sequenced), PhycisphaeraMAG 12 (obtained by metagenomic sequencing), and a marine red alga, Porphyridium purpureumCCMP1328 (from GenBank), were analyzed bioinformatically. RMAR6-6 has the genetic capability to fix nitrogen and produce B vitamins (B1, B2, B5, B6, B9, and B12), bacterioferritin, dimethylsulfoniopropionate (DMSP), and phenylacetate that may enhance algal growth, whereas MAG 12 may have a limited metabolic capability, not producing vitamins B9 and B12, DMSP, phenylacetate, and siderophores, but with the ability to produce bacitracin, possibly modulating algal microbiome. P. purpureumCCMP1328 lacks the genetic capability to fix nitrogen and produce vitamin B12, DMSP, phenylacetate, and siderophore. It was shown that the nitrogen-fixing ability of RMAR6-6 promoted the growth of P. purpureum, and DMSP reduced the oxidative stress of P. purpureum. The metabolic interactions between strain RMAR6-6 and P. purpureumCCMP1328 were also investigated by the transcriptomic analyses of their monoculture and co-culture. Taken together, potential metabolic relationships between Roseibiumand P. purpureumwere proposed. This study provides a better understanding of the metabolic relationships between marine algae and algae-associated bacteria for successful growth.

Enzymes in nature efficiently catalyze chiral organic molecules by elaborately tuning the geometrical arrangement of atoms in the active site. However, enantioselective oxidation of organic molecules by heterogeneous electrocatalysts is challenging because of the difficulty in controlling the asymmetric structures of the active sites on the electrodes. Here, we show that the distribution of chiral kink atoms on high-index facets can be precisely manipulated even on single gold nanoparticles; and this enabled stereoselective oxidation of hydroxyl groups on various sugar molecules. We characterized the crystallographic orientation and the density of kink atoms and investigated their specific interactions with the glucose molecule due to the geometrical structure and surface electrostatic potential.

Mercury (Hg) biomonitoring requires a precise understanding of the internal processes contributing to disparities between the Hg sources in the environment and the Hg measured in the biota. In this study, we investigated the use of Hg stable isotopes to trace Hg accumulation in Adélie and emperor penguin chicks from four breeding colonies in Antarctica. Interspecific variation of Δ199Hg in penguin chicks reflects the distinct foraging habitats and Hg exposures in adults. Chicks at breeding sites where adult penguins predominantly consumed mesopelagic prey showed relatively lower Δ199Hg values than chicks that were primarily fed epipelagic krill. Substantial δ202Hg variations in chick tissues were observed in both species (Adélie: −0.11 to 1.13‰, emperor: −0.27 to 1.15‰), whereas only emperor penguins exhibited the lowest δ202Hg in the liver and the highest in the feathers. Our results indicate that tissue-specific δ202Hg variations and their positive correlations with % MeHg resulted from MeHg demethylation in the liver and kidneys of emperor penguin chicks, whereas Adélie penguin chicks showed different internal responses depending on their exposure to dietary MeHg. This study highlights the importance of considering intra- and interspecific variations in adult foraging ecology and MeHg demethylation when selecting penguin chicks for Hg biomonitoring.

Eight compounds, including 20(R)‐ginsenoside Rg3(1), Ginsenoside Rd (2), ginsenosides Rg2(3), ginsenosides Re (4), β‐sitosterol (5), daucosterol (6), stigmasterol (7), and stigmasterol‐3‐O‐β‐glucoside (8) were isolated from the Panax ginsengsprouts cultivated in Vietnam. Their structures were elucidated by 1H, 13C NMR, and MS spectroscopic techniques and compared with the previous publication. In addition, their inhibitory activity on NO production and cytotoxic effects against human embryonic kidney cells (HEK‐293A) and human hepatocellular carcinoma (HepG2) were evaluated. This is the first study of the phytochemical investigation of P. ginsengsprouts cultivated in Vietnam and ginseng sprouts also contained the same main active ginsenosides as in the 4–6‐year old roots.

This retrospective review of nearly a century of publications in Journalism and Mass Communication Quarterly(JMCQ) traces the maturation of media studies toward a scientific discipline. The field’s dominant paradigms—media effects and communicator uses—persist, adapt, and diversify over time, yielding actionable insights. Challenges include (a) bridging older and newer media theories, (b) harnessing data science, and (c) capitalizing on artificial intelligence/machine learning (AI/ML). Future media research can conceptualize evolving three-dimensional interactions among media, people, and AI. We propose seven initiatives for the next century: revisiting classical theories, fostering interdisciplinary collaboration, balancing descriptive and prescriptive theorization, nurturing indigenous theorizing, collaborating with industry, reverse theorizing with AI, and exploring and regulating AI’s role in media.

The practical utilization of Si electrodes is hindered by their substantial volume expansion during alloying and dealloying processes, which causes mechanical damage and separation from Cu current collectors. To alleviate the problem of Si composite detachment from Cu current collectors, the surface of the Cu current collectors is modified using atmospheric oxygen plasma. Plasma treatment improves the wetting ability of the Cu current collectors and, consequently, the coating quality of the Si electrodes. The uniform distribution of the Si electrode components reduces the sheet resistance and improves the adhesion properties of the Si electrodes containing surface-modified Cu current collectors. As a result, the volume expansion of Si during alloying and dealloying is reduced; this results in an excellent rate capability of 1584 mA h g–1at a current density of 3.6 A g–1(135% that of bare Cu) and excellent cycle performance of 1545 mA h g–1after 300 cycles (Si electrodes with bare Cu exhibit 930 mA h g–1). Therefore, the developed plasma treatment method for Cu current collectors is expected to be an economical and efficient approach for improving the Li–ion battery performance.

The pantograph of electric railway vehicles can cause various mechanical and electrical failures due to contact with the overhead contact wire. This paper presents a system that detects abnormal conditions of a pantograph using five Complementary Metal-Oxide-Semiconductor (CMOS)-based cameras and a laser in the 808 nm band. For the abnormal conditions of the pantograph, three cameras detect defects of the contact strip, while two cameras detect the deformation of pantograph horns. The configuration can detect a range of 1200 mm for defects and abrasion of the pantograph contact strip, and a Field of View of 849 mm with a width of 17.46° and length of 5.72° for the deformation of pantograph horns. However, the performance test of the pantograph abnormal condition detector showed that while the setup could detect each defect, the accuracy was uncertain depending on the type of defect and the angle between the pantograph and camera. A system was configured to detect abnormal conditions of the pantograph for metro railway vehicles on operating lines. The system will be used to verify and maintain test devices for monitoring the state of metro railway.

Synopsis: Improved gas separation using highly electronegative polymer matrix (DOCDA-ODA) and LTA zeolite Mixed matrix membrane for oxygen enrichment. [Display omitted] • A low-cost polyimide (DOCDA-ODA) was used as polymer matrix. • Addition of LTA zeolite improved both O 2 permeability and O 2 /N 2 selectivity. • The high electronegativity of DOCDA-ODA enhanced interfacial interaction with LTA. • The D-MMM exhibited high O 2 /N 2 selectivity of ∼ 15. • The optimum energy consumption for O 2 enrichment (40 % purity) was 44.3 kJ/mol. Membrane technology has advanced, offering high-quality polymeric membranes with great potential for commercial use. However, producing these advanced membranes is usually costly and involves complex manufacturing. To tackle this issue, a cost-effective alternative has emerged in the form of polyimide (PI) membranes, particularly those derived from DOCDA-ODA, a low-cost organic compound. However, the initial gas permeance of DOCDA-ODA membranes is lower than those of commercial PI membranes such as Matrimid® 5218 and 6FDA-DAM membranes. To address this limitation, this study was aimed at fabricating mixed matrix membranes (MMMs) by incorporating zeolite 4A into the DOCDA-ODA matrix. The MMMs demonstrate promising O 2 /N 2 separation performance, surpassing that of Matrimid® 5218-based membranes. Furthermore, they exhibit an O 2 /N 2 selectivity of 14.8 with an O 2 permeability of 2.3 Barrer, surpassing recent benchmarks established by the Robeson upper bounds for polymeric membranes. This exceptional O 2 /N 2 separation performance can be attributed to favorable interfacial interactions between the polymer chains and LTA crystals. Molecular dynamics simulations clarify the role of electronegative atoms, especially oxygen, within the kinked structure of DOCDA-ODA.. Thus, DOCDA-ODA-based MMMs hold potential for O2 purification applications, reducing energy consumption by an impressive 49.3% compared to equivalent commercial membrane processes. [ABSTRACT FROM AUTHOR]

To investigate the virulence profiles and identify clinical and microbiological predictors of mortality in patients with carbapenem-resistant Acinetobacter baumannii(A. baumannii) bacteremia.

It has been widely known that good firms use lower IPO prices to signal their superior prospects to investors. The underlying intuition is that good-type firms signal their type by underpricing their initial issue of shares, because investors can rationally infer that only the best can recoup the signaling cost from subsequent issues. In this paper, we argue that the intuition is not complete. We show that a good firm always has an incentive to deviate to raise the IPO price slightly from its equilibrium price if the price is the only signaling device, implying that signaling by underpricing is not an equilibrium phenomenon in the case of one-dimensional signal. Then, we show that if the firm can choose the equity fraction to be sold as well, a good-type firm can signal its high profitability by choosing a low equity fraction. In this case, a good-type firm engages in underpricing, but it cannot be a signal because both types choose same prices in equilibrium. We also discuss the effect of investor protection laws on IPO underpricing.

Purpose: This study aims to compare and analyze the status of potato cultivation patterns and agricultural machinery use in the USA and South Korea. These results can be used to enhance the productivity and efficiency of potato cultivation in South Korea by improving the mechanization rate of potato farming. Methods: Multiple studies were conducted to collect data and compare the status of each country. Background information on the research and industry was collected through the literature review. On-site information such as mechanization status, main production areas, cultivation technologies, and efficiency was gathered by interviewing local farmers and visiting agricultural sites in both the USA and South Korea. Results: In the USA, the mechanization rate of potato cultivation has reached 100%, leveraging the efficiency of potato production through highly advanced mechanization based on large-scale agricultural systems. In contrast, in South Korea, owing to narrow farmland and geographical characteristics, the mechanization rate is low, and most potato cultivation relies on small agricultural machinery and manual labor. Conclusions: To enhance the productivity and efficiency of potato farming in South Korea, it is essential to develop small multifunctional agricultural machinery tailored to the country’s geographical characteristics. This can be achieved by incorporating advanced agricultural technologies from the USA and standardizing the cultivation methods and machinery operation practices.

The relationship between the microwave dielectric properties and structural characteristics of Mg4Nb2−x(Zr1/2W1/2)xO9(0.05 ≤ x ≤ 0.15) ceramics was investigated along with the microwave dielectric properties of Mg4Nb2−x(Al1/3W2/3)xO9(0.05 ≤ x ≤ 0.15) ceramics for comparison. The quality factors (Qf) of Mg4Nb2−x(Zr1/2W1/2)xO9(MNZW) and Mg4Nb2−x(Al1/3W2/3)xO9(MNAW) were proportional to the average bond valence of the Nb-sites. Mg4Nb1.95(Zr1/2W1/2)0.05O9(Vavg.B= 3.014), which has a higher average bond valence (VB) than that of Mg4Nb2O9(VB= 2.991), showed an excellent Qf; however, Qfdecreased with further substitution. With an increase in the substitution content, the dielectric constant (K) of the specimens decreased, because the dielectric polarizability of the Nb5+(3.97 Å3) was larger than that of the substitution ions such as (Zr1/2W1/2)5+(3.225 Å3) and (Al1/3W2/3)5+(2.397 Å3). The temperature coefficients of resonant frequency (TCF) of the specimens decrease as the Kvalue decreases.

This article presents a 24-GHz highly integrated phased array radar transceiver with four transmitters (TXs) and four receivers (RXs). To realize a wide field of view (FoV) and more efficiently reject the clutters, an automatic beam steering mode is realized. A beam scanning generator (BSG) and a frequency sweep generator (FSG) are proposed to steer the beam for each frequency-modulated continuous wave (FMCW) waveform sequence. The shape of the FMCW waveform, the number of beams, and the steering angles of beams can be reconfigured by initially setting the FSG and BSG. The TXs achieve an output power of 10.6 dBm and beam steering covering angles up to ±50° through a three-stage power amplifier (PA), a 6-bit phase shifter, and a 4-bit attenuator. The RXs achieve a noise figure (NF) of 13.5 dB and an overall gain of 105 dB. In the RXs, a two-stage low-noise amplifier (LNA) employs a low- ${k}$ transformer for flat band gain. A range-compensation filter with a total 40-dB slope is realized using a trans-impedance amplifier (TIA) with DC offset cancellation (DCOC) and first-stage biquad bandpass filter (BPF). The proposed transceiver was fabricated using 65-nm CMOS with an area of $3\times2.8$ mm2.

Optically transparent neural microelectrodes have facilitated simultaneous electrophysiological recordings from the brain surface with the optical imaging and stimulation of neural activity. A remaining challenge is to scale down the electrode dimensions to the single-cell size and increase the density to record neural activity with high spatial resolution across large areas to capture nonlinear neural dynamics. Here we developed transparent graphene microelectrodes with ultrasmall openings and a large, transparent recording area without any gold extensions in the field of view with high-density microelectrode arrays up to 256 channels. We used platinum nanoparticles to overcome the quantum capacitance limit of graphene and to scale down the microelectrode diameter to 20 µm. An interlayer-doped double-layer graphene was introduced to prevent open-circuit failures. We conducted multimodal experiments, combining the recordings of cortical potentials of microelectrode arrays with two-photon calcium imaging of the mouse visual cortex. Our results revealed that visually evoked responses are spatially localized for high-frequency bands, particularly for the multiunit activity band. The multiunit activity power was found to be correlated with cellular calcium activity. Leveraging this, we employed dimensionality reduction techniques and neural networks to demonstrate that single-cell and average calcium activities can be decoded from surface potentials recorded by high-density transparent graphene arrays.