ABSTRACT Keratin is a fibrous protein for stabilizing epithelial cell structures and consisted of nail and hair for protecting tissues and organs. Hair keratin fibers protect the scalp, regulate the temperature, and absorb UV. Their surface morphology, gloss, color, and shape also represent an identical outlook of individuals and a healthy state. However, their physicochemical properties are easily damaged by harmful extrinsic factors such as UV exposure, dryness, high‐temperature styling, bleaching, dyeing, and permanent waving. Despite extensive research for hair keratin protection, conventional haircare products can only promote temporal increase of surface gloss, moisture level, and smoothness by weak adsorption of most ingredients on the keratin surface. In this study, we developed a facile and robust coating layer on hair keratin surface with delaminated Ti3C2 MXene nano‐sheets via bio‐compatible metal‐polyphenol networks (MPN) composed of multivalent metal cations and tea catechin, epigallocatechin gallate (EGCG). Owing to the inherent properties of MXene and polyphenol, this composite coating showed versatile functionalities, including UV screening, rapid thermal dissipation, enhanced mechanical strength, reducing charge accumulation, and sustained antioxidation activity. It could also restore the wettability of human keratin fibers. This coating method can be applicable to other 2D nanomaterials for covering bio‐interfaces.

Titanium dioxide (TiO2) is widely used as an inorganic UV filter because its wide bandgap (similar to 3.2 eV) enables strong UVB blocking; however, this same electronic structure intrinsically limits spectral coverage and promotes photocatalytic generation of reactive oxygen species (ROS). Here, we present a dual-engineered inorganic photoprotective material that simultaneously expands UV-to-high energy visible (HEV) light attenuation and suppresses photo-induced ROS generation by integrating abundant nitrogen (N) doping with a metal-phenolic network (MPN) coating. Ammonia-assisted thermal treatment introduces abundant nitrogen-related defect states into TiO2, extending sub-bandgap absorption into the UVA and HEV regions and promoting carrier recombination rather than photocatalytic charge transfer. Subsequent MPN coating further broadens optical attenuation via ligand-to-metal charge transfer (LMCT) and scavenges residual ROS through catechol and galloyl moieties. Consequently, SiO2/N-TiO2/MPN achieves broad-spectrum optical attenuation (99% UVB, 94% UVA, and 79% HEV), yielding approximately twofold and threefold enhancements in SPF and UVAPF compared to pristine SiO2/TiO2. The cooperative defect-engineered core and redox-active shell sustain suppression of apparent hydroxyl radical generation for 6 h under simulated solar irradiation, while in vitro cell viability assays indicate reduced irradiation-induced cytotoxicity under controlled conditions. This strategy establishes a core-shell paradigm for photochemically suppressed, broad-spectrum inorganic UV filters.

Titanium dioxide (TiO2) is widely used as an inorganic UV filter, but its performance is constrained by a trade-off between spectral coverage and photocatalytic reactive oxygen species (ROS) generation. This limitation is becoming more consequential, as emphasis on risks from high-energy visible light (HEV) exposure makes HEV shielding a pivotal requirement for next-generation sunscreens. Herein, we present a broad-spectrum organic/ inorganic hybrid UV-to-HEV filter platform based on a multi-interface SiO2/TiO2/metal-phenolic network (MPN) heterostructure. By incorporating and immobilizing TiO2 nanocrystals within micro-sized mesoporous SiO2 supports, the platform leverages intrapore entrapment to mitigate nanoparticle-associated safety concerns and lower photocatalytic reactivity. Subsequently, a Zn2+-tannic acid-coordinated MPN layer is assembled on the SiO2/TiO2 surface as an antioxidant passivation barrier, scavenging nearly 99% of the ROS generated by TiO2 for up to 6 h under simulated solar irradiation. In addition, a ligand-to-metal charge transfer-mediated absorption pathway at the TiO2/MPN interface extends the effective photoprotection into the HEV region, resulting in similar to 2.8-fold and similar to 3.5-fold enhancements in sun protection factor and UVA protection factor, respectively. This work highlights organic/inorganic hybrid UV-to-HEV filters as next-generation photoprotective materials, potentially enabling their use as a sole active ingredient for sunscreen products by combining comprehensive spectral protection with a reduced phototoxicity risk.

Wide-bandgap metal-oxide nanoparticles are promising candidates for broad-spectrum sunscreens, yet their application is limited by photocatalytic activity and insufficient high-energy visible (HEV) light absorption. Here, we report a simple, scalable one-pot strategy for the spontaneous formation of a metal-phenolic network (MPN) on zinc oxide (ZnO) nanoparticles (ZnO/MPN NPs), utilizing intrinsic Zn2+ ion release from ZnO to initiate tannic acid (TA) complexation and in situ oxidation. This process forms a nanoscale MPN layer on the ZnO surface, while ZnO-mediated TA oxidation and dimerization (inspired by natural fruit browning) enhance electron delocalization, extending light absorption to the HEV region. The resulting browned MPN-coated ZnO nanoparticles (ZnO/MPN-B NPs) exhibited approximately a threefold enhancement in both sun protection factor (SPF) and UVA protection factor (UVAPF) compared to uncoated ZnO NPs. Additionally, the MPN layer effectively suppresses over 99 % of photogenerated reactive oxygen species (ROS) through its intrinsic ROS scavenging properties, significantly improving photostability. Cell viability assays further demonstrate that the MPN layer mitigates photoinduced cytotoxicity, supporting the safety and biocompatibility of these hybrids. This study suggests ZnO/MPN-B NPs as eco-friendly, high-performance candidates for next-generation sunscreen formulations, offering a scalable, efficient route to address the dual challenges of photoprotection and safety in inorganic sunscreen agents.

Titanium dioxide (TiO2) nanoparticles are extensively used as a sunscreen filter due to their long-active ultraviolet (UV)-blocking performance. However, their practical use is being challenged by high photochemical activities and limited absorption spectrum. Current solutions include the coating of TiO2 with synthetic polymers and formulating a sunscreen product with additional organic UV filters. Unfortunately, these approaches are no longer considered effective because of recent environmental and public health issues. Herein, TiO2-metal-phenolic network hybrid nanoparticles (TiO2-MPN NPs) are developed as the sole active ingredient for sunscreen products through photochemical suppression and absorption spectrum widening. The MPNs are generated by the complexation of tannic acid with multivalent metal ions, forming a robust coating shell. The TiO2-MPN hybridization extends the absorption region to the high-energy-visible (HEV) light range via a new ligand-to-metal charge transfer photoexcitation pathway, boosting both the sun protection factor and ultraviolet-A protection factor about 4-fold. The TiO2-MPN NPs suppressed the photoinduced reactive oxygen species by 99.9% for 6 h under simulated solar irradiation. Accordingly, they substantially alleviated UV- and HEV-induced cytotoxicity of fibroblasts. This work outlines a new tactic for the eco-friendly and biocompatible design of sunscreen agents by selectively inhibiting the photocatalytic activities of semiconductor nanoparticles while broadening their optical spectrum.

For the next generation of mobile products, such as mobile phones, laptops, and wearable devices, high-speed signaling technology for millimeter wave (mmW) or Sub-THz bands is required. To transmit these high-frequency bands, transmission lines like substrate integrated waveguides (SIW) must be used. However, SIWs with via hole structures are unsuitable for the bending sections of flexible PCBs (FPCB), as they can cause copper pattern cracks. In this paper, a novel via-less SIW structure using EMI shielding film is proposed, which can be mass-produced through the FPCB fabrication process. This structure can also be applied to sections where via holes cannot be inserted. The simulated and measured insertion losses of the proposed SIW are 0.020 dB/mm and 0.052 dB/mm, respectively, at 40 GHz.

Solution-processed graphene is beneficial for large-scale, low-cost production. However, its small lateral size, variable layer thickness, and uncontrollable oxidation level still restrict its widespread electronic application. In this study, a newly developed electrochemical exfoliation process was introduced, and a graphene-patched film electrode was fabricated by interfacial self-assembly. We were able to minimize the deterioration of graphene colloids during exfoliation by voltage and electrolyte modulation, but the patched structure of the graphene electrode still showed low conductivity with numerous inter-sheet junctions. Therefore, we determined the optimal conditions for the growth of fully networked silver structures on the multi-stacked graphene film by direct current electro-deposition, and these silver–graphene composite films showed significantly lowered graphene-colloid-patched film surface resistance.

Surface modification of inorganic nanoparticles is critical for the quality and performance of pigments, cosmetics, and composite materials. We covered the titanium dioxide nanoparticles' surface with 2-(acetoacetoxy) ethyl methacrylate, a polymerizable chelating agent. Through the in situ polymerization procedure, this molecule's β-ketoester moiety quickly coordinated with the metal atoms on titanium dioxide nanoparticles, and its methacrylate group formed homogeneous coating layers. This coating layer significantly reduced the photocatalytic activity of titanium dioxide nanoparticles and prevented their aggregation. This nanoparticle dispersion showed low viscosity up to the solid content of 60% (w/w) in the liquid dispersant. As a result, it increased the UV screening performance and dispersion stability. Additionally, this coating layer widened the absorption spectrum of titanium dioxide and could change the color of nanoparticles from pale yellow to brown. It can also be helpful for cosmetic applications.

In this paper, we propose periodic slit ground structure (PSG) to improve the signal integrity of multilevel signals at high data rate such as MIPI C-PHY. Periodic slits are added in the upper and lower ground planes of the stripline structure, without adding additional layers or increasing area, to reduce crosstalk among neighboring lines. The proposed PSG structure can effectively improve the eye-diagram, especially eye height (EH) in multilevel signaling. The effectiveness of the proposed structure is validated through simulation and measurement of PCB-flexible printed circuit board (FPCB)-PCB structure that emulates the interconnected system of MIPI C-PHY signal transmission in a mobile system. The measurements from the test structures show that at a 2.5 Gsps data rate condition, the PSG structures show improvement in EH and eye width (EW) by 38.6% and 9.7%, respectively, compared to stripline structures. The proposed idea can be generally applied in PCB designs that will be used in high speed multilevel signal transmission to improve EH.

Linezolid (LNZ) is one of the most important antimicrobial agents against infections caused by gram-positive bacteria, including enterococci. In a layer operation system, antimicrobial resistance can be transferred to commercial layers via the fecal-oral route. This study investigated the presence and distribution of LNZ-resistant Enterococcus faecalis and Enterococcus faecium in a layer operation system. Among 117 E. faecalis and 154 E. faecium, 10 (8.5%) E. faecalis and 5 (3.2%) E. faecium isolates showed resistance to LNZ and chloramphenicol, and they exhibited multidrug resistance against 5 or more classes of antimicrobial agents. Among the resistant isolates, 9 (90.0%) and 2 (20.0%) E. faecalis harbored optrA and cfr genes, respectively. The optrA and fexA genes were not detected in five LNZ-resistant E. faecium. None of the 15 LNZ-resistant isolates harbored the fexA gene, and no mutations were observed in the genes encoding domain V of 23S ribosomal RNA (rRNA) and ribosomal proteins L3 (rplC) and L4 (rplD). Transferability was identified in three of the nine optrA-positive LNZ-resistant isolates. The tetM, tetL, and ermB genes were cotransferred with the optrA gene in all optrA-positive transconjugants. The results indicate that optrA is well-distributed in E. faecalis, implying a greater level of transferability. Thus, enhanced surveillance efforts are needed to monitor the emergence and spread of optrA in enterococci in layer operation system.

We investigated the characteristics and persistence of Escherichia coli resistant to third-generation cephalosporins (3GCs) by early administration of ceftiofur or gentamicin and to analyze the impact of 3GC use in hatcheries. We studied 10 ceftiofur-treated flocks (CTFs) and 10 gentamicin-treated flocks (GTFs) of layers. Fecal samples were collected at 1, 2, 4, 8, 18, and 30 weeks of age for all flocks. Among the 446 E. coli isolates, 58 (29.0 %) of 200 isolates in CTFs were identified as 3GC-resistant E. coli and 28 (11.4 %) of 246 isolates in GTFs were identified as 3GC-resistant E. coli. The presence of 3GC-resistant E. coli isolates at 1, 2, and 4 weeks was significantly higher in CTFs than in GTFs (p < 0.05). Moreover, the rate of resistance to 3GCs gradually decreased from 83.3 % at 1 week of age to 4.4 % at 30 weeks of age in CTFs. Of the 86 3GC-resistant E. coli isolates, 32 isolates had β-lactamase-encoding gene: blaCTX-M-14 (ten isolates), blaCTX-M-15 (three isolates), blaCMY-2 (five isolates), and blaTEM-1 (twenty-five isolates) genes. Plasmid replicon typing revealed that blaCTX-M-14, blaCTX-M-15, blaCMY-2, and blaTEM-1 were located on F, F and FIB, I1 and K, and I1 and FII, respectively. Furthermore, 18 isolates carried class 1 integrons, with four different gene cassettes. These results revealed that ceftiofur used in hatcheries can lead to an increase in the number of 3GC-resistant E. coli with many characteristics. A voluntary ban must be imposed on the use of 3GCs for 1-day-old chicks in poultry industry.

The use of antimicrobials in food animals is the major determinant for the propagation of resistant bacteria in the animal reservoir. Especially, parent stock (PS) produces thousands of eggs for commercial laying hens and can transfer a variety of viral and bacterial agents to chicks. The objective of this study was to investigate the presence and distribution of third-generation cephalosporin-resistant and extended-spectrum β-lactamase (ESBL)- and plasmid-mediated AmpC (pAmpC)-producing Escherichia coli in the PS level of the layer operation system in Korea. A total of 591 E. coli isolates were tested in this study and resistance to the first-generation cephalosporins ranged from 60.0% to 71.1%, whereas the resistance to the second- and third-generation cephalosporins ranged from 18.3% to 28.9% and from 8.3% to 14.5%, respectively. Of the 65 third-generation cephalosporin-resistant E. coli isolates, 51 (78.5%) showed multidrug resistance and 18 (27.7%) exhibited phenotypic and genotypic characteristics of ESBL/pAmpC-producing E. coli. With regard to ESBL/pAmpC gene prevalence, only the CMY-2 gene was identified in all 18 ESBL/pAmpC-producing E. coli and two isolates possessed both the CMY-2 and TEM-1 genes. Pulsed-field gel electrophoresis (PFGE) analysis of the 18 CMY-2-producing E. coli isolates revealed four PFGE patterns from the same PS farm and flock and accorded both CMY-2 genes and antimicrobial resistance pattern. To the best of our knowledge, this is the first study to investigate the prevalence and characteristics of third-generation cephalosporin-resistant and CMY-2-producing E. coli isolated at the layer PS level; our findings support the critical need for a comprehensive surveillance program to monitor the emergence and dissemination of third-generation cephalosporin resistance.

In the poultry industry, commercial layer farms play an important role in meeting the protein demand through the supply of eggs. However, the risk of contamination by β-lactamase-producing Escherichia coli in eggs laid by commercial chickens is significant. In this study, we investigated the rate of extended-spectrum β-lactamase (ESBL) and plasmid-mediated AmpC (pAmpC) β-lactamase-producing E. coli isolated from layer hens and characterized their molecular background. Among the 92 cefotaxime-resistant E. coli isolates, 66 (71.7%) were identified as multidrug resistant and 29 showed phenotypic and genotypic characteristics of β-lactamase-producing E. coli. The ESBL/pAmpC genes blaCTX-M-1, blaCTX-M-14, blaCTX-M-15, and blaCMY-2 were detected in 1, 6, 5, and 4 isolates, respectively. The non-ESBL/pAmpC gene blaTEM-1 was found in 16 isolates. Three isolates harbored both blaTEM-1 and blaCTX-M-14 genes. A total of 12 isolates also carried class 1 integrons, with 3 different gene cassette arrangements found in 8 of these isolates. A pulsed-field gel electrophoresis (PFGE) analysis of the 29 β-lactamase-producing E. coli isolates revealed that 4 PFGE patterns were consistent with the β-lactamase gene and layer farm origin, and showed a similar antibiotic resistance pattern. Our results suggest that comprehensive surveillance and more prudent use of third-generation cephalosporins in commercial layer farms is necessary to prevent the dissemination of ESBL/pAmpC-producing E. coli.

Enterococcus faecalis (E. faecalis) and Enterococcus faecium (E. faecium) are ubiquitous intestinal bacteria in humans and animals that can easily acquire antimicrobial resistance, which allows them to have roles as antimicrobial resistance indicators. In addition, layer parent stock produces thousands of eggs for the production of commercial laying hens and can transfer a variety of viral and bacterial agents to chicks. The objective of this study was to determine the prevalence and characteristics of antimicrobial-resistant E. faecalis and E. faecium isolated in the layer parent stock level of the egg-layer operating system in South Korea. A total of 129 E. faecalis and 166 E. faecium isolates from 74 flocks of 30 layer parent stock were tested for resistance in this study. The prevalence of doxycycline- (51.9%), erythromycin- (53.5%), high-level gentamicin- (13.2%), high-level kanamycin- (31.0%), high-level streptomycin- (30.2%), and tetracycline- (64.3%) resistant E. faecalis isolates were higher than those for E. faecium isolates (P < 0.05). The ermB gene was detected in 66 (95.7%) erythromycin-resistant E. faecalis isolates, which was higher than that of 32 (71.7%) erythromycin-resistant E. faecium isolates. Twenty-one high-level gentamicin-resistant Enterococcus spp. (17 E. faecalis and 4 E. faecium) carried at least one aminoglycoside-modifying enzyme gene, aac(6')Ie-aph(2')-Ia or ant(6)-Ia. Fourteen isolates that harbored both aac(6')Ie-aph(2')-Ia and ant(6)-Ia exhibited pattern A with IS256 at both ends. Ten high-level ciprofloxacin-resistant Enterococcus spp. (8 E. faecalis and 2 E. faecium) showed amino acid changes from serine to isoleucine at codons 83 in gyrA, and 80 in parC. Also, the virulence genes ace, asa1, efaA, and gelE were detected in this study. To the best of our knowledge, this is the first study to examine the prevalence and characteristics of antimicrobial-resistant E. faecalis and E. faecium isolates in the layer parent stock. Our findings support the need for a surveillance program to monitor the emergence of antimicrobial-resistant E. faecalis and E. faecium in layer operating system.

무기탄소원으로부터 에탄올을 생산하는 acetogenic 박테리아인 Clostridium ljungdahlii 발효공정에서 배양 배지 조성에 따른 영향을 분석하여 균주 성장과 에탄올 생산 향상을 시도하였다. 균주 성장 및 에탄올 생산에 영향을 줄 수 있는 배지 구성성분으로 yeast extract, fructose, NH4Cl, K2HPO4를 선정하였다. Yeast extract 농도가 증가할수록 균주 성장과 에탄올 생산이 증가하였으며 에탄올 비생산성은 yeast extract 기본 배지 농도보다 낮은 0.05 g/L에서 가장 높았다. Fructose 농도가 증가할수록 균주 성장은 증가하였지만 5 g/L을 초과하는 fructose 투입은 에탄올 생산을 감소시켰다. Yeast extract 5 g/L인 조건에서 fructose 5 g/L와 넣었을 때 에탄올 생산농도가 0.297 g/L로 가장 높았으나, fructose를 넣지 않았을 때 매우 낮은 균주 농도로 인해 에탄올 비생산성은 0.281 g/g DCW로 높았다. NH4Cl은 균주 성장이나 에탄올 생산은 큰 차이를 보이지 않았으며 30 g/L 이상 과다 투입하면 성장저해가 나타났다. K2HPO4에 대해서는 농도가 증가할수록 균주 성장과 에탄올 생산이 모두 증가하였다. NH4Cl과 K2HPO4를 사용한 경우 에탄올 비생산성은 yeast extract를 적게 사용한 경우 크게 나타났다.

UV 및 블루라이트를 차단하는 세륨 옥사이드 나노 입자와 다공성 실리카와의 복합입자를 건식 코팅 공정을 통해 제조하였다. 실리카와 세륨 옥사이드 간 혼합 비율과 메카노 퓨전 장치의 챔버 회전속도 등의 제조 조건을 달리하여 여러 복합입자를 만든 후, 입자 표면 형태를 SEM으로 관측 비교하고 XRF을 통해 복합입자의 ...

The layer operation system has a pyramidal structure in which the grandparent stock (GPS) is at the top, followed by the parent stock (PS), and commercial chickens (CC) that produce eggs at the bottom of the pyramid. Unfortunately, this vertical integration of the layer industry allows the transfer of Escherichia coli(E. coli) to the next step. The objective of this study was to genetically characterize and investigate the prevalence of third-generation cephalosporin-resistant E. coli at all levels of the layer operation system in Korea. A total of 561 E. coli samples were tested in this study, and antimicrobial resistance to third-generation cephalosporin, cefotaxime, and ceftazidime gradually increased from GPS to CC. Fifty-one (9.1%) isolates produced β-lactamase genes: GPS harbored blaTEM-1 (1 isolate) or blaCMY-2 (2 isolates) genes; PS harbored blaTEM-1 (7 isolates) or blaCMY-2 (6 isolates) genes; CC harbored blaCTX-M-1 (1 isolate), blaCTX-M-14 (1 isolate), blaTEM-1 (13 isolates), blaCTX-M-14+TEM-1 (7 isolates), or blaCMY-2 (4 isolates) genes; and eggs harbored blaCTX-M-1 (2 isolates), blaCTX-M-14 (1 isolate), blaTEM-1 (3 isolates), or blaCMY-2 (3 isolates) genes. Pulsed-field gel electrophoresis (PFGE) analysis was performed on the 51 β-lactamase-producing E. coli isolates. In PFGE, E. coli included 7 PFGE patterns showing the same production stage and exhibited both β-lactamase genes and the antimicrobial resistance pattern. Our findings suggest that there is a critical need for comprehensive surveillance of third-generation cephalosporin-resistant E. coli at all levels of the layer-production pyramid and provide important considerations for the control of infection in large-scale layer operations in Korea.

This study was designed to access the efficacy and safety of the Femoseal vascular closure device(VCD) to achieve hemostasis in antegrade access of the common femoral artery(CFA). We retrospectively reviewed the outcome of Femoseal VCD used for hemostasis in 144 accesses to the CFA in 134 patients between August 2013 to April 2015. Femoseal VCD was used for closure in all cases. Technical success was defined as immediate closure of CFA puncture site achieved by use of Femoseal VCD. Puncture direction, patients’ demographics, factors affecting hemostasis, deployment success/failure, complications were investigated. A total of 144 Femoseal VCDs were deployed in 134 patients. Of the 144 CFA accesses, antegrade approach was 78 and retrograde approach was 66 cases. Technical success rate was 100%. Major vascular complications were found in three cases (antegrade CFA approach group:1, retrograde CFA approach group:2) and minor vascular complications were found in 19 cases (antegrade CFA approach group: 10, retrograde CFA approach group: 9). There were no significant statistical differences between antegrade approach and retrograde approach groups. Femoseal VCD is effective and safe for closure of antegrade CFA access site offering high technical success and acceptable complication rate.

Recently, there has been increased interest in self-healing membranes containing functional microcapsules in relation to challenges involving water treatment membranes. In this study, a self-healing membrane has been prepared by incorporating microcapsules with a polyurethane (PU) shell and a diisocyanate core in a poly(ether sulfone) (PES) membrane. Depending on the characteristics of the microcapsule, to precisely quantify the self-healing behavior and performance of the produced microcapsule embedded membranes, it is important to understand the effect of a used surfactant on microcapsule synthesis. It is noteworthy that mixed surfactants have been employed to control and tailor the size and morphology of microcapsules during the synthetic process, and the surfactant system employed was one of the most dominant parameters for affecting the healing capability of microcapsule embedded membranes. Various techniques including microscopy (optical and electron), thermal analyses (DSC and TGA), and water flux measurements have been employed. This article provides essential and important information for future research into the subtle relation between microcapsule properties with varied synthetic parameters and the self-healing behavior of membrane.