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A novel bacterial strain designated CJ43T was isolated from fresh water located in Jeongseon-gun, Gangwon-do, South Korea, displaying multi-drug resistance. The isolate was observed to be Gram-stain-negative, aerobic, orange-pigmented, and rod-shaped. Strain CJ43T grew optimally at 30 ℃ and pH 7 on R2A agar in the absence of NaCl. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain CJ43T belongs to the genus Pedobacter in the family Sphingobacteriaceae and was the most closely related to Pedobacter glucosidilyticus 1-2T (98.1% sequence similarity). The whole-genome sequencing of strain CJ43T was performed using the PacBio RS II platform, revealing a genome size of 3.9 Mb in a single contig with DNA G+C content of 34.9%. The genome included 3144 predicted protein-coding genes, as well as 55 tRNA, 9 rRNA and 3 ncRNA genes. The genome also contained 92 putative antibiotic resistance genes, reflecting its phenotypes. The average nucleotide identity and in silico digital DNA-DNA hybridization values between strain CJ43T and P. glucosidilyticus 1-2T were 88.7%, and 38.6%, respectively. The major fatty acids of strain CJ43T were iso-C15:0, iso-C17:0 3-OH, and summed feature 3 (C16:1 ω6c and/or C16:1 ω7c). Strain CJ43T contained phosphatidylethanolamine as a major polar lipid and menaquinone-7 as a sole respiratory quinone. Based on the polyphasic taxonomy data, strain CJ43T represents a novel species of the genus Pedobacter, for which the name Pedobacter aquae sp. nov. is proposed with the type strain CJ43T (= KACC 21350T = JCM 33709T).

G protein-coupled receptors (GPCRs) regulate diverse intracellular signaling pathways through the activation of heterotrimeric G proteins. However, the effects of the sequential activation–deactivation cycle of G protein on the conformational changes of GPCRs remains unknown. By developing a Förster resonance energy transfer (FRET) tool for human M3 muscarinic receptor (hM3R), we find that a single-receptor FRET probe can display the consecutive structural conversion of a receptor by G protein cycle. Our results reveal that the G protein activation evokes a two-step change in the hM3R structure, including the fast step mediated by Gq protein binding and the subsequent slower step mediated by the physical separation of the Gαq and Gβγ subunits. We also find that the separated Gαq-GTP forms a stable complex with the ligand-activated hM3R and phospholipase Cβ. In sum, the present study uncovers the real-time conformational dynamics of innate hM3R during the downstream Gq protein cycle.

In this study, catalytic inverse vulcanization based on trialkyl amines (TAAs) is presented. With oleophilic alkyl chain moieties, low-cost organic TAAs promote time-efficient reactions as nucleophilic activators, even at a...

Current research has focused on effective solutions to mitigate global warming and the accelerating greenhouse gas emissions. Compared to most cooling methods requiring energy and resources, passive daytime radiative cooling (PDRC) technology offers excellent energy savings as it requires no energy consumption. However, existing PDRC materials encounter unprecedented problems such as complex structures, low flexibility, and performance degradation after stretching. Thus, this study reports a porous structured thermoplastic polyurethane (TPU) film with bimodal pores to produce high-efficiency PDRC with efficient solar scattering using a simple process. The TPU film exhibited an adequately high solar reflectivity of 0.93 and an emissivity of 0.90 in the atmospheric window to achieve an ambient cooling of 5.6 °C at midday under a solar intensity of 800 W m

This study revealed that the synthesis of effective flow modifiers using diamine monomers and fatty acid reduces the melt viscosity of polyamide 66 (PA66) composites. Moreover, the study provided insights into the rheological and mechanical properties of these reinforced polymers. In particular, the oligomers hexamethylenediamide, dodecamethylene diamide, 4,4′-methylenebis(cyclohexylamide) (i.e., HMDA, DMDA, MCHA) to modify the PA66 were prepared from hexamethylenediamine, dodecamethylene diamine, 4,4′-methylenebis(cyclohexylamine). The synthesized modifiers showed thermal stability in the PA66 processing temperature. Further, the chemical similarity increased due to amide bonds in the backbone of the flow modifiers, showing good compatibility with PA66. Additionally, PA66/glass fiber (GF) composites containing the flow modifier showed enhanced rheological and mechanical properties. The flow modifiers significantly improved the tensile strength and flexural modulus of the PA66/GF composites. The proposed synthetic method is straightforward, opening up a new strategy for reducing the melt viscosity of PA66 without degradation of the mechanical properties. The method improves the compatibility of the PA66/GF composites even in high amounts of GF, achieving effective polymer processing for practical applications.

Current research has focused on effective solutions to mitigate global warming and the accelerating greenhouse gas emissions. Compared to most cooling methods requiring energy and resources, passive daytime radiative cooling (PDRC) technology offers excellent energy savings as it requires no energy consumption. However, existing PDRC materials encounter unprecedented problems such as complex structures, low flexibility, and performance degradation after stretching. Thus, this study reports a porous structured thermoplastic polyurethane (TPU) film with bimodal pores to produce high-efficiency PDRC with efficient solar scattering using a simple process. The TPU film exhibited an adequately high solar reflectivity of 0.93 and an emissivity of 0.90 in the atmospheric window to achieve an ambient cooling of 5.6°C at midday under a solar intensity of 800 W/m2. Thus, the highly elastic and flexible TPU film was extremely suitable for application on objects with complex shapes. The radiative cooling performance of 3D-printed models covered with these TPU films demonstrated their superior indoor cooling efficiency compared to commercial white paint (8.76°C). Thus, the proposed design of high-efficiency PDRC materials is applicable in various urban infrastructural objects such as buildings and vehicles.

This study investigates the occurrence of 36 pesticides-including 33 that were monitored from 2007 to 2019 in Korean rivers-in wastewaters from pesticide manufacturing facilities (PMFs) and in 13 pesticide wastewater treatment plants (PWWTPs). Furthermore, an approach for the effective removal of these pesticides from pesticide wastewater (PW) is proposed. Among the 36 pesticides investigated, 32 were found to be present in the PMF wastewater and PWWTP influents (at concentrations ≤466.8 mg/L). In addition, 24 of the 36 pesticides were detected in PWWTP effluents, indicating that effluents are discharged without the complete removal of many pesticides. Moreover, the PWWTP effluent influences the presence of pesticides in river (confidence interval: ≥ 95%; p 0.05). Although the chemical oxidation-activated sludge process is frequently recommended for the treatment of PWs, the findings from the current study indicate that an activated sludge-activated carbon adsorption process is more suitable for PW treatment due to its superior removal efficiency, treatment stability, and economic feasibility. Consequently, its application for the treatment of PWs can markedly decrease the levels of pesticides discharged into rivers.

Chyle leakage after modified radical neck dissection is a rare condition that could be occasionally life-threatening if untreated. We report the first case of successful management of a thoracic duct injury using Viscum album extract (Helixor-M). A 54-year-old woman diagnosed with papillary thyroid cancer of the right lobe of the thyroid with metastasis to cervical lymph node levels II-VI, bilaterally, underwent total thyroidectomy and modified radical neck dissection. Three days postoperatively, the surgical team identified a thoracic duct injury due to drainage of chyle from the Jackson-Pratt drain inserted in the right side of the patient`s neck. Various medical treatments (octreotide, withdrawal of enteral feeding, and total parenteral nutrition) and surgical treatments [lymphatic ligation of cervical lymph node level IV and negative pressure wound therapy (vacuum-assisted closure)] were performed, but the drainage persisted. Viscum album extract (Helixor-M) was then injected through the drain. The dose of Viscum album extract was increased while being cautious of its adverse effects, such as nausea, vomiting, erythema, induration at the injection site, and flu-like symptoms. The injection was effective in stopping the drainage and the patient’s condition improved, without recurrence. The patient was discharged on the 64(th) postoperative day without any further complications. Our results suggest that treatment of thoracic duct injury after neck surgery with Viscum album extract (Helixor-M) may be a novel, less invasive alternative approach to treat cases resistant to standard treatments.

The prognosis of patients with node-negative T1b tumors according to human epidermal growth factor receptor 2 (HER2) status is not known. This group of patients has not been studied in the available randomized trials. The objective of this study was to evaluate the survival of patients in a monoethnic group diagnosed with T1b lymph node-negative breast cancer depending on HER2 status. We analyzed 3110 patients with T1bN0M0 breast cancer whose data were deposited into the Korean Breast Cancer Society Registry database between 2000 and 2009. Overall survival (OS) and breast cancer-specific survival (BCSS) were compared according to HER2 status. Among all patients, 494 (15.9%) had HER2-positive breast cancer. At a mean follow-up of 93 months, 108 deaths and 86 breast cancer-specific deaths were noted among all patients. There was no significant difference in OS between the HER2-negative and HER2-positive groups (p = 0.103). The same result was observed for BCSS. However, in the subgroup of estrogen receptor (ER)-positive women, HER2-negative patients had a better BCSS prognosis than HER2-positive patients (p = 0.025). Multivariate analysis also indicated a significant difference in BCSS in the ER-positive subgroup (HR 2.60; 95% CI 1.15–5.87; p = 0.021). This study analyzed a large nationwide and monoethnic cohort and found a significant difference only in BCSS in the ER-positive subgroup according to HER2 status. Anti-HER2 therapy may be considered in HER2-positive and ER-positive patients with small, node-negative breast cancer.

A simple way to control the gate dielectric properties of vinyl-addition polynorbornene copolymers bearing pendant vinyl groups (P(NB/VNB)) through thiol–ene click chemistry is reported. The optimized content ratio of tetra-thiol cross-linkers leads to the enhanced gate dielectric properties and performance of organic field-effect transistors. Also, this approach provides photo-patternability, low-temperature solution-processing, and air-processability.

A multifunctional gate dielectric material based on dual cross-linked aromatic polythiourea (c-PTU) networks for organic field-effect transistors is presented. Tailoring the dual covalent and noncovalent cross-links in the c-PTU gate dielectric enables all the advantageous capabilities of excellent insulating properties, including high capacitance, good solvent resistance and thermal stability, as well as low-temperature solution processing and photo-patterning.

Ridge-cut explosive bolts are a type of pyrotechnic release devices in which two connected structures are separated by explosives. They are designed such that shock waves can interact with and cut their body. Furthermore, they provide a clean separation surface and require a smaller explosive amount compared with other types of explosive bolts. In this study, ridge-cut explosive bolts of various diameters and with an exploding bridge wire (EBW) detonator were developed for use in sled testing. Their initial shapes were designed using an established procedure. Initial separation tests for the initial designs of the explosive bolts showed that considerable debris was produced for some models and that the explosive amount should be reduced. For the minimization of the number of experiments, the appropriate explosive amount was determined in advance through numerical analysis, which was performed using Autodyn, a commercial hydrocode. The numerical analysis technique used was improved to analyze the complete separation phenomena. The numerical results clearly revealed the separation mechanism and characteristics of the explosive bolts and helped determine an appropriate explosive amount for achieving a small amount of debris. Verification tests confirmed that explosive amounts determined using the numerical results were appropriate for separation and generated a small amount of debris.

An electrochemical microchip sensor was fabricated through the photolithographic process. The metal paste used in the micro-pattern of the sensor chip contained dendritic and spherical Ag-coated Cu powders, which decreased the electrical resistance of the pattern down to 25.69 Ω·cm by forming a network for electron transfer between particles. The electrode materials were dendritic palladium oxide-nickel oxide powders that showed dramatically high surface area. Also, a synergetic effect on the sensing performance between palladium oxide and nickel oxide was observed. The formation of micro-pattern was investigated through optical microscope and field-emission scanning electron microscope. The body resistance of the conductive paste was calculated using the 4-point probe technique, and the electrochemical characteristics of the sensor were analyzed by cyclic voltammetry and chronoamperometry. The fabricated sensor chip exhibited sensing performance for hydrogen peroxide detection with high sensitivity of 641.75 µA mM−1 cm−2 in a dynamic range between 50 µM and 13 mM. Its long-term stability and high selectivity were also confirmed.

In this paper, describe the fabrication of high strength punch molds that can be applied to ultra-high strength sheet materials after processing. A method for improving the strength of the punching die by additive manufacturing (AM) of a high strength powder material using a metal 3D printer was proposed. Furthermore, a semi-additive technique was proposed to increase the punch strength through partial AM of specific parts of the punch that require high strength. A preprocessing process for predicting the semi-additive shape for the punch function portion is proposed for application of the AM technology of a metal 3D printer to this semi-additive technique. The preprocessing for determining the semi-additive shape consists of the predicting step of the punch strength based on the shear process of the sheet material, analyzing step the stress distribution of the punch, defining step the semi-additive range, designing step the semi-additive shape, and verifying step the additive interface strength. Based on this simulation, the range of shapes for the semi-additive was 1.21 mm and 2.62 mm for sheet material CP1180 and 1.3 mm and 3.2 mm for sheet material 22MnB5. The shape and range determined in the simulation process defines a semi-additive area (volume) for the 3D printing AM technique using a high-strength powder material, and a semi-additive punch was manufactured according to the defined area. The semi-additive punch (HWS powder material) fabricated in this study was performed a durability test for validity verification in the piercing process of high-strength sheet material (CR980). This validation test compared the state of the punch after 1000 piercing processes with a typical cold piercing punch (SKD11 solid material). From this test, the feasibility of the semi-additive punch was confirmed by showing a similar state of scratches and abrasion from the two punches. The simulation analysis processor for the additive shape and the additive range prediction for the semi-additive punch manufacturing presented in this paper can be useful for the additive manufacture of cutting and trimming punch mold.

Harvesting solar energy and generating steam through solar thermal energy are viable approaches with diverse applications such as power generation, desalination, and water purification. Particularly, for efficient and stable solar desalination, hierarchically porous materials are desired to enable the required multiple functionalities. However, high thermal/chemical energy required and time consumed remain roadblocks. In this study, a facile, fast, and scalable laser-induced photothermal method to achieve flexible monolithic bilayer sheets (MBS) of hierarchically porous graphitic carbon (HPGC) and polymeric foam for use in salt-resistant and flexible solar steam generators is reported. The MBS-based self-floating solar steam generator shows outstanding solar desalination performance with a solar thermal efficiency of 83.2% (1-sun) and a high salt-rejection ratio (99.9%). Efficient solar thermal energy transformation is achieved by the versatile multi-functionalities of the MBS, including broad-spectrum solar light absorption, heat localization, and capillary action. Anisotropic wetting properties of hydrophobic HPGC and hydrophilic polyimide (PI) foam effectively prevent salt accumulation on the HPGC surface. The salt-resistant MBS enable long-term stability for solar desalination with actual seawater. Our laser-based photothermal method has potential in the development of high-performance solar thermal systems with substantial cost reduction by scalable production of multiscale hierarchically structured materials from micro-structured polymers.

Nanoporous silicon is a promising anode material for high energy density batteries due to its high cycling stability and high tap density compared to other nanostructured anode materials. However, the high cost of synthesis and low yield of nanoporous silicon limit its practical application. Here, we develop a scalable, low-cost top-down process of controlled oxidation of Mg2Si in the air, followed by HCl removal of MgO to generate nanoporous silicon without the use of HF. By controlling the synthesis conditions, the oxygen content, grain size and yield of the porous silicon are simultaneously optimized from commercial standpoints. In situ environmental transmission electron microscopy reveals the reaction mechanism; the Mg2Si microparticle reacts with O2 to form MgO and Si, while preventing SiO2 formation. Owing to the low oxygen content and microscale secondary structure, the nanoporous silicon delivers a higher initial reversible capacity and initial Coulombic efficiency compared to commercial Si nanoparticles (3,033 mAh/g vs. 2,418 mAh/g, 84.3% vs. 73.1%). Synthesis is highly scalable, and a yield of 90.4% is achieved for the porous Si nanostructure with the capability to make an excess of 10 g per batch. Our synthetic nanoporous silicon is promising for practical applications in next generation lithium-ion batteries.

Structural colors have advantages compared with chemical pigments or dyes, such as iridescence, tunability, and unfading. Many studies have focused on developing the ability to switch ON/OFF the structural color; however, they often suffer from a simple and single stimulus, remaining structural colors, and target selectivity. Herein, we present regionally controlled multistimuli-responsive structural color switching surfaces. The key part is the utilization of a micropatterned DNA-hydrogel assembly on a single substrate. Each hydrogel network contains a unique type of stimuli-responsive DNA motifs as an additional cross-linker to exhibit swelling/deswelling via stimuli-responsive DNA interactions. The approach enables overcoming the existing limitations and selectively programming the DNA-hydrogel to a decrypted state (ON) and an encrypted state (OFF) in response to multiple stimuli. Furthermore, the transitions are reversible, providing cyclability. We envision the potential of our method for diverse applications, such as sensors or anticounterfeiting, requiring multistimuli-responsive structural color switching surfaces.

The synthesis and characterization of poly(phenylene polysulfide) networks (PSNs) with controlled average sulfur ranks, from elemental sulfur (ES) and

Background The increasing prevalence of resistance against the last-resort antibiotic colistin is a significant threat to global public health. Here, we discovered a novel colistin resistance mechanism via enzymatic inactivation of the drug and proposed its clinical importance in microbial communities during polymicrobial infections. Results A bacterial strain of the Gram-negative opportunistic pathogen Stenotrophomonas maltophilia capable of degrading colistin and exhibiting a high-level colistin resistance was isolated from the soil environment. A colistin-degrading protease (Cdp) was identified in this strain, and its contribution to colistin resistance was demonstrated by growth inhibition experiments using knock-out (Δcdp) and complemented (Δcdp::cdp) mutants. Coculture and coinfection experiments revealed that S. maltophilia carrying the cdp gene could inactivate colistin and protect otherwise susceptible Pseudomonas aeruginosa, which may seriously affect the clinical efficacy of the drug for the treatment of cystic fibrosis patients with polymicrobial infection. Conclusions Our results suggest that Cdp should be recognized as a colistin resistance determinant that confers collective resistance at the microbial community level. Our study will provide vital information for successful clinical outcomes during the treatment of complex polymicrobial infections, particularly including S. maltophilia and other colistin-susceptible Gram-negative pathogens such as P. aeruginosa.

A Gram-stain-negative, aerobic and motile bacterial strain, designated CJ34T, was isolated from Han River water in the Republic of Korea. Strain CJ34T grew optimally on tryptic soy agar at 30 °C and pH 7.0 in the absence of NaCl. Results of phylogenetic analysis based on 16S rRNA gene sequence showed that strain CJ34T belonged to the genus Comamonas within the family Comamonadaceae and was most closely related to Comamonas testosteroni ATCC 11996T and Comamonas thiooxydans DSM 17888T (both 98.63 % similarity). The average nucleotide identity values between strain CJ34T and two closely related type strains C. testosteroni ATCC 11996T and C. thiooxydans DSM 17888T were 82.77 and 82.73 %, respectively. The major isoprenoid quinone of strain CJ34T was ubiquinone Q-8. The major cellular fatty acids of strain CJ34T were C16 : 0, C16 : 1 ω6c and/or C16 : 1 ω7c and C18 : 1 ω6c and/or C18 : 1 ω7c. The predominant polar lipids of strain CJ34T were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and an unidentified aminophospholipid. Whole genome sequencing revealed that strain CJ34T had a genome of 4.9 Mbp and the G+C content of the genomic DNA was 59.73 mol%. On the basis of the results of this polyphasic taxonomy study, strain CJ34T represents a novel species in the genus Comamonas , for which the name Comamonas fluminis sp. nov. is proposed. The type strain is CJ34T (=KACC 22237T=JCM 34454T).

Background There is an increasing interest in HER2-low breast cancer with promising data from clinical trials using novel anti-HER2 antibody–drug conjugates. We explored the differences in clinicopathological characteristics and survival outcomes between HER2-low and HER2-IHC 0 breast cancer. Methods Using nationwide data from the Korean Breast Cancer Registry between 2006 and 2011, 30,491 patients with stages I to III breast cancer were included in the analysis: 9,506 (31.2%) in the HER2-low group and 20,985 (68.8%) in the HER2-IHC 0 group. Kaplan–Meier and Cox proportional hazards regression survival analysis were used to compare breast cancer-specific survival between the two groups. Results HER2-low breast cancer was more frequent in patients with hormone receptor-positive breast cancer than in those with triple-negative breast cancer. In patients with hormone receptor-positive breast cancer, HER2-low breast cancer was associated with fewer T4 tumors, higher histological grade, and a negative lymphatic invasion. In patients with triple-negative breast cancer, HER2-low breast cancer was associated with a high lymph node ratio and positive lymphatic invasion. HER2-low breast cancer was significantly associated with a lower Ki-67 labeling index. No significant difference was observed in overall survival between the two groups. HER2-low breast cancer showed significantly better breast cancer-specific survival than HER2-IHC 0 breast cancer, regardless of the hormone receptor status. In multivariate analysis, the impact of low HER2 expression on breast cancer-specific survival was significant only in triple-negative breast cancer (HRs, 0.68; 95% CI, 0.49–0.93; P = 0.019). Conclusions These findings suggest that the biology and clinical impact of low HER2 expression can differ according to the hormone receptor status and support the need for further investigation on the understanding of the biology of HER2-low breast cancer.

Stretchable electronic circuits are critical in a variety of next-generation electronics applications, including soft robots, wearable technologies, and biomedical applications. To date, printable composite conductors comprising various types of conductive fillers have been suggested to achieve high electrical conductance and excellent stretchability. Among them, liquid metal particles have been considered as a viable candidate filler that can meet the necessary prerequisites. However, a mechanical activation process is needed to generate interconnected liquid channels inside elastomeric polymers. In this study, we have developed a chemical strategy of surface-functionalizing liquid metal particles to eliminate the necessity of additional mechanical activation processes. We found that the characteristic conformations of the polyvinylpyrrolidone surrounding eutectic gallium indium particles are highly dependent on the molecular weight of polyvinylpyrrolidone. By virtue of the specific chemical roles of polyvinylpyrrolidone, the as-printed composite layers are highly conductive and stretchable, exhibiting an electrical conductivity approaching 8372 S/cm at 100% strain and an invariant resistance change of 0.92 even at 75% strain after a 60,000 cycle test. The results demonstrate that the self-activated liquid metal-based composite conductors are applicable to traditional stretchable electronics, healable stretchable electronics, and shape-morphable applications.

Room temperature sodium–sulfur (RT Na–S) batteries have distinct advantages over other next generation batteries because of their use of abundant and inexpensive resources with high theoretical capacities of 1166 and 1675 mA h g−1, namely for sodium and sulfur. However, problematic side reactions, called the shuttle effect, lead to low coulombic efficiency during cycling. Here, we propose a new strategy to fundamentally suppress the shuttle phenomenon by combining two widely used concepts, covalent bonds and physical confinement, through the preparation of a PIM-1-based carbon–sulfur composite. This sulfur–carbon material was prepared through one-step heat treatment of a mixture of sulfur and PIM-1. The resulting sulfur–carbon composites have characteristics of both ∼0.5 nm-sized ultra-micropores and covalent bonding in a single material, which fundamentally obstruct the dissolution of polysulfide into the electrolyte. This strategy led to long cycling stability over 250 cycles, with a capacity of 556 mA h gs−1 and a coulombic efficiency of approximately 100%.

Purpose The aim of this study was to investigate the therapeutic efficacy of adjuvant modalities for elderly Asian breast cancer patients using population-based data from the Korean Breast Cancer Registry database. Methods We identified 53,582 patients who underwent curative surgery between January 2005 and December 2010. The primary end point was the comparison of overall survival between the administration or omission of adjuvant treatment modalities, including endocrine treatment, radiation therapy, and chemotherapy, in the elderly group (older than 75 years) compared with the control group (younger than 75 years). Results Of the 53,582 patients analyzed, the total number of elderly patients was 901 (1.7%), and the number of control patients was 52,681 (98.3%). Although elderly patients were found to have larger tumor sizes (p = 0.024) and higher pathological stages (p

The synthesis and characterization of poly(phenylene polysulfide) networks (PSNs) with controlled average sulfur ranks, from elemental sulfur (ES) and p-diiodobenzene (DIB), are investigated. The P...