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Single‐atom‐based catalysts are intriguing electrocatalytic platforms that combine the advantages of molecular catalysts and conductive carbon‐based materials. In this work, hybrids (Co‐NrGO‐1 and Co‐NrGO‐2) were generated by wet‐reactions between organometallic complexes (Co(CH 3 COO) 2 and Co[CH 3 (CH 2 ) 3 CH(C 2 H 5 )COO] 2 , respectively) and N‐doped reduced graphene oxide at 25°C. Various characterizations revealed the formation of atomically dispersed Co(O) 4 (N) species in Co‐NrGO‐2. Density functional theory (DFT) calculations explained the effect of the aliphatic C7 group in Co2 on the formation processes. The Co‐NrGO‐2 hybrid showed excellent catalytic performance, such as onset (0.94 V) and half‐wave (0.83 V) potentials, for electrochemical oxygen reduction reaction (ORR). Co‐NrGO‐2 outperformed Co‐NrGO‐1, which was explained by more back donation to the antibonding orbitals of O 2 from electron‐rich aliphatic groups. DFT calculations support this feature, with mechanistic investigations showing favored ORR reactions and facile breakage of double bonds in O 2 .

Graphene-based materials show excellent properties in various applications because of their electrical properties, large surface areas, and high tolerance for chemical modification. The use of wet-process is a promising way for their mass production. Heteroatom doping is one of the common methods to improve their electrical, physical, and electrochemical properties. In this work, we develop a new route for the production B-doped graphene-based materials using low-temperature wet-process, which is the reaction between graphene oxide suspensions and a BH 3 adduct in tetrahydrofuran under reflux. Elemental mapping images show well-dispersed B atoms along the materials. Various spectroscopic characterizations confirm the reduction of the graphene oxide and incorporation of B atoms into the carbon network as high as ~ 2 at%. The materials showed electrocatalytic activity for oxygen reduction reactions.

To address the demands of emerging data‐centric computing applications, ferroelectric field‐effect transistors (Fe‐FETs) are considered the forefront of semiconductor electronics owing to their energy and area efficiency and merged logic–memory functionalities. Herein, the fabrication and application of an Fe‐FET, which is integrated with a van der Waals ferroelectrics heterostructure (CuInP2S6/α‐In2Se3), is reported. Leveraging enhanced polarization originating from the dipole coupling of CIPS and α‐In2Se3, the fabricated Fe‐FET exhibits a large memory window of 14.5 V at VGS = ±10 V, reaching a memory window to sweep range of ≈72%. Piezoelectric force microscopy measurements confirm the enhanced polarization‐induced wider hysteresis loop of the double‐stacked ferroelectrics compared to single ferroelectric layers. The Landau–Khalatnikov theory is extended to analyze the ferroelectric characteristics of a ferroelectric heterostructure, providing detailed explanations of the hysteresis behaviors and enhanced memory window formation. The fabricated Fe‐FET shows nonvolatile memory characteristics, with a high on/off current ratio of over 106, long retention time (>104 s), and stable cyclic endurance (>104 cycles). Furthermore, the applicability of the ferroelectrics heterostructure is investigated for artificial synapses and for hardware neural networks through training and inference simulation. These results provide a promising pathway for exploring low‐dimensional ferroelectronics. The authors report on the fabrication and application of a ferroelectric transistor integrated with a van der Waals ferroelectrics heterostructure (CuInP2S6/α‐In2Se3). Leveraging enhanced polarization originating from the dipole coupling, the fabricated device exhibits a large memory window and nonvolatile memory characteristics with long retention time and stable cyclic endurance, providing a promising pathway for exploring low‐dimensional ferroelectronics.

Carfilzomib (CFZ) is a peptide epoxyketone proteasome inhibitor approved for the treatment of multiple myeloma (MM). Despite the remarkable efficacy of CFZ against MM, the clinical trials in patients with solid cancers yielded rather disappointing results with minimal clinical benefits. Rapid degradation of CFZ in vivo and its poor penetration to tumor sites are considered to be major factors limiting its efficacy against solid cancers. We previously reported that polymer micelles (PMs) composed of biodegradable block copolymers poly(ethylene glycol) (PEG) and poly(caprolactone) (PCL) can improve the metabolic stability of CFZ in vitro. Here, we prepared the CFZ-loaded PM, PEG-PCL-deoxycholic acid (CFZ-PM) and assessed its in vivo anticancer efficacy and pharmacokinetic profiles. Despite in vitro metabolic protection of CFZ, CFZ-PM did not display in vivo anticancer efficacy in mice bearing human lung cancer xenograft (H460) superior to that of the clinically used cyclodextrin-based CFZ (CFZ-CD) formulation. The plasma pharmacokinetic profiles of CFZ-PM were also comparable to those of CFZ-CD and the residual tumors that persisted in xenograft mice receiving CFZ-PM displayed an incomplete proteasome inhibition. In summary, our results showed that despite its favorable in vitro performances, the current CFZ-PM formulation did not improve in vivo anticancer efficacy and accessibility of active CFZ to solid cancer tissues over CFZ-CD. Careful consideration of the current results and potential confounding factors may provide valuable insights into the future efforts to validate the potential of CFZ-based therapy for solid cancer and to develop effective CFZ delivery strategies that can be used to treat solid cancers.

Sargassum horneri (SH) is a promising marine bioresource for producing bioactive compounds. Recently, the biological functions (including anti-inflammatory, antioxidant, and anticancer activities) of SH extracts have been revealed; however, efficient extraction processes to produce bioactive molecules (such as tannin and phenol) have not been carefully designed. In this study, the ultrasound-assisted extraction process was optimized based on the response surface methodology (RSM) to efficiently produce tannin and phenol from SH. Significant RSM models (p < 0.05) for predicting tannin and phenol yields were developed, and prethanol A concentration, temperature, and solid loading were significantly affected by tannin or phenol yield (p < 0.05). Following numerical optimization, the tannin and phenol yields achieved 14.59 and 13.83 mg/g biomass, respectively, under optimal conditions (39.1% solvent, 61.9 °C, 52.0 g/L solid loading, and 49.0% amplitude), similar to the model-predicted values (12.95 and 13.37 mg/g, respectively). Then, time profiling under optimal conditions determined the optimal time as 10.0 min, resulting in the highest yield (15.88 mg tannin and 14.55 mg phenol/g). The extracts showed antioxidant activity (IC50: 79.86 μg/mL) comparable to that of ascorbic acid (vitamin C). It was found to be particularly non-toxic, raising its potential as a functional ingredient in food or cosmetics.

Flexible memristors are promising candidates for multifunctional neuromorphic computing applications, overcoming the limitations of conventional computing devices. However, unpredictable switching behavior and poor mechanical stability in conventional memristors present significant challenges to achieving device reliability. Here, a reliable and flexible memristor using zirconium‐oxo cluster (Zr6O4OH4(OMc)12) as the resistive switching layer is demonstrated. The optimization of the structural rigidity of the hybrid oxo‐cluster network by thermal polymerization allows the precise formation of dispersed conductive cluster networks, enhancing the repeatability of the resistive switching with mechanical flexibility. The optimized memristor exhibits endurance of ∼104 cycles and stable memory retention performance up to 104 s, maintaining a high ION/IOFF ratio of 104 under a bending radius of 2.5 mm. Moreover, the device achieves a pattern recognition accuracy of 97.44%, enabled by highly symmetric analog switching with multilevel conductance states. These results highlight that hybrid metal‐oxo clusters can provide novel material design principles for flexible and reliable neuromorphic applications, contributing to the development of artificial neural networks. The development of flexible synaptic memristors faces considerable challenges, including low cyclic endurance, limited on–off ratios, and asymmetry in conductance changes, while ensuring mechanical flexibility. This study demonstrates reliable synaptic characteristics with highly linear analog conductance modulation by utilizing a Zr6‐oxo cluster‐based memristor, highlighting their potential as advanced flexible memory components for artificial neural networks and neuromorphic computing applications.

Although statins have been suggested to attenuate the progression of diabetic cardiomyopathy, its effect without glycemic control remains unclear. Therefore, we evaluated the effect of pravastatin on diabetic rat hearts according to glycemic control. Rats were randomly divided into five groups: control (C), diabetes (D), diabetes with insulin (I), diabetes with pravastatin (P), and diabetes with insulin and pravastatin (IP). Eight weeks after allocated treatments, the heart was extracted and analyzed following echocardiography. Cardiac fibrosis was measured using Masson’s trichrome stain. Cardiac expression of collagen I/III, matrix metalloproteinase (MMP)-2, MMP-9, and angiotensin-converting enzyme (ACE)/ACE2 was evaluated by immunohistochemistry and/or Western blot. Enzyme-linked immunosorbent assay was used for measuring reactive oxygen species (ROS). Diabetic groups without glycemic control (D and P) showed significantly impaired diastolic function and increased levels of cardiac fibrosis, collagen I/III, MMP-2, MMP-9, and ROS production. However, there were little significant differences in the outcomes among the control and two glucose-controlled diabetic groups (I and IP). Groups C and IP showed more preserved ACE2 and lower ACE expressions than the other groups did (D, I, and P). Our study suggested glycemic control would be more important to attenuate the progression of diabetic cardiomyopathy than pravastatin medication.

Owing to the evolution of data‐driven technologies, including the large language models, generative artificial intelligence, autonomous driving, and the internet of things requires advanced memory technology. However, conventional memory device structures and fabrication process have significant limitations for high‐density integration. Herein, this study reports the monolithically‐integrated 1‐selector and 1‐resistive (1S1R) synaptic memory in van der Waals (vdW) heterostructure, which overcomes the conventional limitations of device integration technologies. Single‐step direct synthesis of vdW heterostructure and its corresponding 1S1R cell is fabricated via plasma‐enhanced lattice‐distortion. Scanning‐transmission electron microscopy, and X‐ray photoelectron spectroscopy are correlatively applied to observe the effects of plasma‐enhanced nano‐crystallization of bulk vdW VSe2. Furthermore, bipolar resistive switching dynamics have been spatially resolved with conductive atomic force microscopy. Furthermore, the artificial vdW heterostructure exhibits the synaptic functionality with interfacial charge accumulation at the 2D/3D interface, enabling linear weight updates across multiple resistance states with minimal nonlinearity. In conclusion, it envision that the monolithically‐integrated 1S1R cell can offers a systematic device platform for next‐generation vdW electronics and its corresponding monolithic 3D integration. Monolithically‐integrated van der Waals synaptic memory is presented via bulk nano‐crystallization, which overcomes the conventional limitations of 3D device integration technologies. Furthermore, bipolar resistive switching (LRS/HRS) dynamics is spatially resolved with conductive atomic force microscopy, scanning‐transmission electron microscopy, and X‐ray photoelectron spectroscopy. The monolithic‐integrated 1S1R device exhibits the low leakage currents, robust switching ratios, and reliable bipolar memory states with synaptic response. The monolithically‐integrated resistive memory will offer the generalizable platform for next‐generation 3D integrated neuromorphic device and edge‐computing AI hardware.

Longitudinal bone growth ceases with growth plate senescence during puberty. However, the molecular mechanisms of this phenomenon are largely unexplored. Here, we examined Wnt-responsive genes before and after growth plate senescence and found that CXXC finger protein 5 (CXXC5), a negative regulator of the Wnt/β-catenin pathway, was gradually elevated with reduction of Wnt/β-catenin signaling during senescent changes of rodent growth plate. Cxxc5 −/− mice demonstrated delayed growth plate senescence and tibial elongation. As CXXC5 functions by interacting with dishevelled (DVL), we sought to identify small molecules capable of disrupting this interaction. In vitro screening assay monitoring CXXC5–DVL interaction revealed that several indirubin analogs were effective antagonists of this interaction. A functionally improved indirubin derivative, KY19382, elongated tibial length through delayed senescence and further activation of the growth plate in adolescent mice. Collectively, our findings reveal an important role for CXXC5 as a suppressor of longitudinal bone growth involving growth plate activity.

Imaging the intrinsic optical absorption properties of nanomaterials with optical microscopy (OM) is hindered by the optical diffraction limit and intrinsically poor sensitivity. Thus, expensive and destructive electron microscopy (EM) has been commonly used to examine the morphologies of nanostructures. Further, while nanoscale fluorescence OM has become crucial for investigating the morphologies and functions of intracellular specimens, this modality is not suitable for imaging optical absorption and requires the use of possibly undesirable exogenous fluorescent molecules for biological samples. Here we demonstrate super-resolution visible photoactivated atomic force microscopy (pAFM), which can sense intrinsic optical absorption with ~8 nm resolution. Thus, the resolution can be improved down to ~8 nm. This system can detect not only the first harmonic response, but also the higher harmonic response using the nonlinear effect. The thermoelastic effects induced by pulsed laser irradiation allow us to obtain visible pAFM images of single gold nanospheres, various nanowires, and biological cells, all with nanoscale resolution. Unlike expensive EM, the visible pAFM system can be simply implemented by adding an optical excitation sub-system to a commercial atomic force microscope. Super-resolution microscopy: Breaking the diffraction limit without dyes Super-resolution microscopy based on light-activated atomic force microscopy has been demonstrated a team in Korea. The diffraction limit makes it difficult to image structures smaller than about 200 nanometres using optical microscopy. While several super-resolution fluorescence microscopy techniques have been realized, there is a need for a super-resolution technique that does not use fluorescent dyes. Chulhong Kim of Pohang University of Science and Technology in Korea and co-workers have realized a resolution of 8 nanometres by using a pulsed laser beam to optically excite a sample and then observing the response using a conventional atomic force microscope. The researchers demonstrated their system by using it to image single gold nanoparticles as well as cancer and plant cells. They anticipate that it could find use in fields as diverse as physics, biology, chemistry, medicine and material science.