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Monolayer transition metal dichalcogenides are materials with an atomic structure complementary to graphene but diverse properties, including direct energy bandgaps, which makes them intriguing candidates for optoelectronic devices. Various approaches have been demonstrated for the growth of molybdenum disulphide (MoS 2 ) on insulating substrates, but to date, growth of isolated crystalline flakes has been demonstrated at random locations only. Here we use patterned seeds of molybdenum source material to grow flakes of MoS 2 at predetermined locations with micrometre-scale resolution. MoS 2 flakes are predominantly monolayers with high material quality, as confirmed by atomic force microscopy, transmission electron microscopy and Raman and photoluminescence spectroscopy. As the monolayer flakes are isolated at predetermined locations, transistor fabrication requires only a single lithographic step. Device measurements exhibit carrier mobility and on/off ratio that exceed 10 cm 2  V −1  s −1 and 10 6 , respectively. The technique provides a path for in-depth physical analysis of monolayer MoS 2 and fabrication of MoS 2 -based integrated circuits. Although synthesis of high-quality MoS 2 has been demonstrated, growth of monolayer MoS 2 at controlled locations is highly desirable for applications. Here, the authors introduce a method where patterned seeds of molybdenum source material are used to grow isolated flakes at predetermined locations.

Biliary atresia is a rare, progressive disease that affects the bile ducts in newborns. Persistent bile duct obstruction induces various pathological conditions, including jaundice, inflammation, and liver fibrosis; however, the exact pathogenesis of biliary atresia is not yet fully understood. Nuclear factor-κB (NF-κB) is widely acknowledged as a key regulator in the pathogenesis of hepatitis and liver fibrosis, and extensive research has been conducted to develop strategies to effectively inhibit its activity to mitigate liver damage. Exosome-based therapeutic platforms offer targeted NF-κB inhibition with low immunogenicity and enhanced liver-specific delivery. This study aimed to evaluate the therapeutic efficacy of Exo-SrIκB in treating cholestatic liver fibrosis using experimental animal models. Exo-SrIκB (an exosome-based therapy containing the super-repressor IκB protein) using EXPLOR technology (Exosome engineering for Protein Loading via Optically Reversible protein-protein interactions) to encapsulate the super repressor IκB (SrIκB) within exosomes. The therapeutic efficacy of Exo-SrIκB was assessed in minipig and mouse models with experimentally induced cholestatic liver disease. Administration of Exo-SrIκB significantly attenuated liver fibrosis progression in both animal models by inhibiting NF-κB nuclear translocation and reducing the expression of fibrotic markers. Treated animals exhibited reduced collagen deposition, lower α-SMA levels, and improved hepatic function compared to untreated controls. Exo-SrIκB effectively suppressed NF-κB signaling and alleviated liver fibrosis in experimental cholestatic liver disease models, suggesting that exosome-based therapeutics may offer a targeted and biocompatible application to managing liver fibrosis and other chronic liver diseases.

While existing studies regarding organizational vacillation theory have focused on examining how vacillation may lead to ambidexterity, few studies have focused on how vacillation itself happens and whether it happens symmetrically or not. To bridge this research gap, this paper analyzed organizational vacillation over time with two canonical cases while examining patterns of organizational structure over time. Unlike previous studies that only revealed the existence of vacillation between centralization and decentralization, this study revealed that vacillation is observed with an asymmetric ratio of duration in the business world by finding that each company within the same industry spends a greater portion of time in a certain organizational structure than the other. By analyzing these changes throughout the business history, this study found that organizational vacillation happens asymmetrically while alternatively shifting between centralization and decentralization. Based on the case study result, this study draws propositions that can enable future researchers to advance theoretical and empirical understanding toward asymmetric vacillation.

We demonstrate high-performance down-conversion microlens array (DC-MLA) films for white organic light-emitting diodes (OLEDs). The DC-MLA films are readily fabricated by an imprinting method based on breath figure patterns, which are directly formed on the polymer substrate with a novel concept. The DC-MLA films result in high-quality white light as well as enhanced light outcoupling efficiency for white OLEDs. The external quantum efficiency and power efficiency of OLEDs with DC-MLA films are increased by a factor of 1.35 and 1.86, respectively, compared to OLEDs without outcoupling films. Moreover, the white OLEDs with DC-MLA films achieve a high color-rendering index of 84.3. It is anticipated that the novel DC-MLA films fabricated by the simple imprinting process with breath figure patterns can contribute to the development of efficient white OLEDs.

Bismuth telluride has garnered considerable attention owing to its versatile properties applicable in thermoelectric and antibacterial domains, as well as its intriguing topological insulating properties. In this work, our group fabricated bismuth telluride thin films with various ratios using radio frequency magnetron sputtering. The surface properties of these thin films were thoroughly analyzed by employing a diverse array of analytical techniques, including X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), four-point probe and contact angle (CA) measurements. Specifically, our XPS findings indicated that Bi is more susceptible to oxidation than Te following Ar+-ion etching. Pure Te thin films exhibited the highest Rq value of 31.2 nm based on AFM and SEM results due to their larger grain sizes. The XRD patterns revealed a peak at 27.75° for thin films with 20% Te, attributed to its rhombohedral structure. Moreover, thin films with 30% Te yielded the highest weighted average work function with a value of 4.95 eV after etching. Additionally, pristine Bi and Te thin films demonstrated the most robust hydrophobic properties compared to intermediate-composition thin films, as determined by CA measurements.

Korea revived its small-scale industry (SSI) reservation policy in the early 2010s to protect small businesses and promote their competitiveness. However, whether this size-contingent entry regulation causes allocative inefficiency remains a subject of debate. This study examines the effects of SSI reservation on both the performance of small plants and allocative efficiency in the Korean ready-mixed concrete industry. By exploiting the exogenous variation in preexisting large plants across geographically independent markets, we find that the SSI policy increases the average productivity of small plants in the affected markets. However, the policy decreases competition, thereby causing allocative inefficiency in the reserved industries.

Metabolic dysfunction-associated steatohepatitis (MASH) is a significant contributor to hepatocellular carcinoma (HCC). To validate AMPK activation as a therapeutic strategy for MASH-associated liver fibrosis, we investigated the effects of a 4-chloro-benzenesulfonamide derivative named KN21, a novel AMPK activator, on the liver fibrogenic process in a MASH model. In mice fed a choline-deficient, L-amino acid-defined, high fat diet (CDAHFD), KN21 reduced hepatic steatosis, lipid accumulation, and liver fibrosis. In hepatocyte cells treated with palmitic acid and oleic acid (PO), KN21 attenuated lipid accumulation and the release of reactive oxygen species (ROS) and fibrotic mediators. Hepatic stellate cells stimulated with hepatocyte-derived conditioned medium (CM) exhibited increased expression of fibrosis markers, whereas hepatic stellate cells exposed to CM from KN21-treated hepatocytes showed a decrease of fibrosis marker expression. Additionally, KN21 inhibited the activation of human hepatic stellate cells and demonstrated potent antifibrotic activity. These findings underscore the therapeutic potential of pharmacological AMPK activation for the treatment of MASH-associated liver fibrosis.

The rapid growth of e-commerce is widely blamed for job losses in brick-and-mortar retailers. We construct a unique measure of online spending share based on 30 billion transactions of credit cards in Korea. Using the geographic variation in online spending shares, we examine the causal effect of e-commerce on retail employment at the county level. We find that the rise in online spending share from 2010 to 2015 decreases the county-level offine retail employment by about 172 workers, which represents approximately 3% reduction in average retail employment. We also find that the employment shifts from offine retail to other local businesses, such as restaurants and personal services. However, such effects of employment shift are confined in metropolitan areas and fall far short of offsetting employment losses in non-metropolitan areas. Our finding implies a prospect of Retail Job Apocalypse in certain local labor markets (i.e., non-metropolitan areas), if not everywhere.

The fabrication of functional tissues is essential for clinical applications such as disease treatment and drug discovery. Recent studies have revealed that the mechanical environments of tissues, determined by geometric cell patterns, material composition, or mechanical properties, play critical roles in ensuring proper tissue function. Here, we propose an acoustophoretic technique using surface acoustic waves to fabricate therapeutic vascular tissue containing a three-dimensional collateral distribution of vessels. Co-aligned human umbilical vein endothelial cells and human adipose stem cells that are arranged in a biodegradable catechol-conjugated hyaluronic acid hydrogel exhibit enhanced cell-cell contacts, gene expression, and secretion of angiogenic and anti-inflammatory paracrine factors. The therapeutic effects of the fabricated vessel constructs are demonstrated in experiments using an ischemia mouse model by exhibiting the remarkable recovery of damaged tissue. Our study can be referenced to fabricate various types of artificial tissues that mimic the original functions as well as structures. Engineering 3D tissues faces the challenge of adequate vascularisation for nutrient delivery and gas exchange deep inside the construct. Here the authors use surface acoustic waves to create an aligned array of blood vessels in a hyaluronic acid hydrogel and use it to improve function in a mouse hindlimb ischemia model.

Bio‐enabled and bio‐mimetic nanomaterials represent functional materials, which use bio‐derived materials and synthetic components to bring the better of two, natural and synthetic, worlds. Prospective broad applications are flexibility and mechanical strength of lightweight structures, adaptive photonic functions and chiroptical activity, ambient processing and sustainability, and potential scalability along with broad sensing/communication abilities. Here, we summarize recent results on relevant functional photonic materials with responsive behavior under mechanical stresses, magnetic field, and changing chemical environment. We focus on recent achievements and trends in tuning optical materials' properties such as light scattering, absorption and reflection, light emission, structural colors, optical birefringence, linear and circular polarization for prospective applications in biosensing, optical communication, optical encoding, fast actuation, biomedical fields, and tunable optical appearance. Introduction of stimuli‐responsive and/or functional materials into bio‐inspired materials and structures enables that of materials and structures to act as multi‐functional photonic devices such as switchable colorimetric adhesives, multi‐logic value bio‐computing, and colorimetric stress/strain sensor.