From Solution to Thin Film: Molecular Assembly of π-Conjugated Systems and Impact on (Opto)electronic Properties.

The assembly of conjugated organic molecules from solution to solid-state plays a critical role in determining the thin film morphology and optoelectronic properties of solution-processed organic electronics and photovoltaics. During evaporative solution processing, π-conjugated systems can assemble via various forms of intermolecular interactions, forming distinct aggregate structures that can drastically tune the charge transport landscape in the solid-state. In blend systems composed of donor polymer and acceptor molecules, assembly of neat materials couples with phase separation and crystallization processes, leading to complex phase transition pathways which govern the blend film morphology. In this review, we provide an in-depth review of molecular assembly processes in neat conjugated polymers and nonfullerene small molecule acceptors and discuss their impact on the thin film morphology and optoelectronic properties. We then shift our focus to blend systems relevant to organic solar cells and discuss the fundamentals of phase transition and highlight how the assembly of neat materials and processing conditions can affect blend morphology and device performance.

Efficiency and Mechanism of Catalytic Siloxane Exchange in Vitrimer Polymers: Modeling and Density Functional Theory Investigations.

Of late, siloxane-containing vitrimers have gained significant interest due to their fast dynamic characteristics over a reasonable temperature range (180-220 °C), making them well-suited for diverse applications. The exchange reaction pathway in the siloxane vitrimers is accountable for the covalent adaptive network, with the reaction's effectiveness being regulated by either organic or organometallic catalysts. However, directly studying the exchange reaction pathway in the bulk phase using experimental approaches is challenging because of the intricate and interconnected structure of these vitrimers. Here, we perform comprehensive density functional theory (DFT) and experimental investigations to discover the detailed catalytic efficacy of siloxane exchange and provide direction for the reaction process using a 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) catalyst. The calculated transition barrier energy and catalytic efficiency of hexamethyldisiloxane and dihydroxy-dimethylsilane exchange derived from the nudged elastic band with transition-state calculations strongly agree with the experimental findings. In addition, Fukui indices, along with partial charges, are employed to evaluate the nucleophilic and electrophilic behaviors of silanol and siloxane molecules. Our analysis revealed that by utilizing the Fukui indices of both the acid and the base, we can make an approximate estimation of the respective kinetics of the SN2 process in the siloxane exchange reaction mechanism. These findings establish a foundation for comprehending a crucial aspect of the exchange mechanism in siloxane vitrimer systems and could aid in the development of novel catalysts.

SMART SKY EYE System for Preliminary Structural Safety Assessment of Buildings Using Unmanned Aerial Vehicles.

The development of unmanned aerial vehicles (UAVs) is expected to become one of the most commercialized research areas in the world over the next decade. Globally, unmanned aircraft have been increasingly used for safety surveillance in the construction industry and civil engineering fields. This paper presents an aerial image-based approach using UAVs to inspect cracks and deformations in buildings. A state-of-the-art safety evaluation method termed SMART SKY EYE (Smart building safety assessment system using UAV) is introduced; this system utilizes an unmanned airplane equipped with a thermal camera and programmed with various surveying efficiency improvement methods, such as thermography, machine-learning algorithms, and 3D point cloud modeling. Using this method, crack maps, crack depths, and the deformations of structures can be obtained. Error rates are compared between the proposed and conventional methods.

Photoabsorption Imaging at Nanometer Scales Using Secondary Electron Analysis.

Optical imaging with nanometer resolution offers fundamental insights into light-matter interactions. Traditional optical techniques are diffraction limited with a spatial resolution >100 nm. Optical super-resolution and cathodoluminescence techniques have higher spatial resolutions, but these approaches require the sample to fluoresce, which many materials lack. Here, we introduce photoabsorption microscopy using electron analysis, which involves spectrally specific photoabsorption that is locally probed using a scanning electron microscope, whereby a photoabsorption-induced surface photovoltage modulates the secondary electron emission. We demonstrate spectrally specific photoabsorption imaging with sub-20 nm spatial resolution using silicon, germanium, and gold nanoparticles. Theoretical analysis and Monte Carlo simulations are used to explain the basic trends of the photoabsorption-induced secondary electron signal. Based on our current experiments and this analysis, we expect that the spatial resolution can be further improved to a few nanometers, thereby offering a general approach for nanometer-scale optical spectroscopic imaging and material characterization.

Crystallinity-dependent device characteristics of polycrystalline 2D n = 4 Ruddlesden-Popper perovskite photodetectors.

Ruddlesden-Popper (RP) perovskites have attracted a lot of attention as the active layer for optoelectronic devices due to their excellent photophysical properties and environmental stability. Especially, local structural properties of RP perovskites have shown to play important roles in determining the performance of optoelectronic devices. Here, we report the photodetector performance variation depending on the crystallinity of n = 4 two-dimensional (2D) RP perovskite polycrystalline films. Through controlling the solvent evaporation rate, 2D RP perovskite films could be tuned between highly- and randomly-orientated phases. We investigated how different factors related to the film crystallinity are reflected in the variation of photodetector performances by considering grain boundary and low energy edge state effects in n = 4 RP perovskites. Better understanding the interplay between these factors that govern the photophysical properties of the devices would be beneficial for designing high-performance RP perovskite-based optoelectronic devices.

Proton irradiation effects on mechanochemically synthesized and flash-evaporated hybrid organic-inorganic lead halide perovskites.

A hybrid organic-inorganic halide perovskite is a promising material for developing efficient solar cell devices, with potential applications in space science. In this study, we synthesized methylammonium lead iodide (MAPbI3) perovskites via two methods: mechanochemical synthesis and flash evaporation. We irradiated these perovskites with highly energetic 10 MeV proton-beam doses of 1011, 1012, 1013, and 4 × 1013protons cm-2and examined the proton irradiation effects on the physical properties of MAPbI3perovskites. The physical properties of the mechanochemically synthesized MAPbI3perovskites were not considerably affected after proton irradiation. However, the flash-evaporated MAPbI3perovskites showed a new peak in x-ray diffraction and an increased fluorescence lifetime in time-resolved photoluminescence under high-dose conditions, indicating considerable changes in their physical properties. This difference in behavior between MAPbI3perovskites synthesized via the abovementioned two methods may be attributed to differences in radiation hardness associated with the bonding strength of the constituents, particularly Pb-I bonds. Our study will help to understand the radiation effect of proton beams on organometallic halide perovskite materials.

Effect of Atmospheric-Pressure Plasma Treatments on Fracture Toughness of Carbon Fibers-Reinforced Composites.

In this study, nano-scale fillers are added to epoxy matrix-based carbon fibers-reinforced composites (CFRPs) to improve the mechanical properties of multi-scale composites. Single-walled carbon nanotubes (SWCNTs) used as nano-scale fillers are treated with atmospheric-pressure plasma to introduce oxygen functional groups on the fillers' surface to increase the surface free energy and polar component, which relates to the mechanical properties of multi-scale composites. In addition, the effect of dispersibility was analyzed through the fracture surfaces of multi-scale composites containing atmospheric-pressure plasma-treated SWCNTs (P-SWCNTs) under high load conditions. The fillers content has an optimum weight percent load at 0.5 wt.% and the fracture toughness (KIC) method is used to demonstrate an improvement in mechanical properties. Here, KIC was calculated by three equations based on different models and we analyzed the correlation between mechanical properties and surface treatment. Compared to the composites of untreated SWCNTs, the KIC value is improved by 23.7%, suggesting improved mechanical properties by introducing selective functional groups through surface control technology to improve interfacial interactions within multi-scale composites.

Highly Stable Contact Doping in Organic Field Effect Transistors by Dopant-Blockade Method.

In organic device applications, a high contact resistance between metal electrodes and organic semiconductors prevents an efficient charge injection and extraction, which fundamentally limits the device performance. Recently, various contact doping methods have been reported as an effective way to resolve the contact resistance problem. However, the contact doping has not been explored extensively in organic field effect transistors (OFETs) due to dopant diffusion problem, which significantly degrades the device stability by damaging the ON/OFF switching performance. Here, the stability of a contact doping method is improved by incorporating "dopant-blockade molecules" in the poly(2,5-bis(3-hexadecylthiophen-2-yl)thieno[3,2-b]thiophene) (PBTTT) film in order to suppress the diffusion of the dopant molecules. By carefully selecting the dopant-blockade molecules for effectively blocking the dopant diffusion paths, the ON/OFF ratio of PBTTT OFETs can be maintained over 2 months. This work will maximize the potential of OFETs by employing the contact doping method as a promising route toward resolving the contact resistance problem.

Analytical methods for determination of carbonyl compounds and nicotine in electronic No-Smoking aid refill solutions.

The present investigation aimed to develop analytical methods to determine carbonyl compounds and nicotine and to assess the carbonyl compounds and nicotine concentrations in commercial refill solutions for electronic no-smoking aids (ENSAs). The analytical methods for carbonyl compounds and nicotine in refill solutions for ENSAs were developed and analyzed from 30 popular branded products by gas chromatography and liquid chromatography. They were then validated in terms of linearity of the calibration curve, limit of detection (LOD), limit of quantification (LOQ), accuracy (%), and precision (%). Further, the existence of carbonyl compounds and nicotine in the refill solutions for ENSAs was also evaluated. None of the samples contained nicotine, but carbonyl compounds were sensed in a concentration range from 0.9 to 11.65 µg/mL. Manufacturers of ENSA refill solutions have advertised no-smoking aids as less harmful than tobacco cigarettes and as free from harmful substances. However, carbonyl compounds were detected in all 30 samples. The investigation of ENSA refill solutions needs to be broadened to gain a better accepting of the existence of harmful materials in ENSA refill solutions and prevent unsuspected ill-health effects.

Physical activity status in relation to quality of life and dietary habits in breast cancer survivors: subset analyses of KROG 14-09 nationwide questionnaire study.

PURPOSE: We investigated the relationship of physical activity with dietary habits and quality of life (QoL) in breast cancer survivors in accordance with the recommendations of the American Cancer Society. METHODS: Data of 928 breast cancer survivors were obtained from the KROG 14-09 study to measure QoL in early phase after adjuvant radiotherapy. According to the extent of physical activity, survivors were divided into four groups: inactivity (0-149 min/week, N = 144), regular activity (150-450 min/week, N = 309), moderate activity (451-900 min/week, N = 229), and marked activity (901-1800 min/week, N = 164) excluding hyperactivity (> 1800 min/week, N = 82) as it is a difficult condition to recommend to survivors. Global physical activity questionnaire, 5-dimensional questionnaire by EuroQoL (EQ-5D-3L), QoL Questionnaire-breast cancer (QLQ-BR23) from EORTC, and dietary habits were surveyed. A linear-to-linear association test for EQ-5D-3L and Kruskal-Wallis analysis for QLQ-BR23 and dietary habit were conducted. RESULTS: Overall, 15.5% respondents (144/928) were classified as physically inactive. The trends of frequent intake of fruits (p = 0.001) and vegetable (p = 0.005) and reluctance toward fatty food (p < 0.001) were observed in physically active groups. Mobility (p = 0.021) and anxiety (p = 0.030) of EQ-5D-3L, and systemic therapy side effect (p = 0.027) and future perspective (p = 0.008) of QLQ-BR23 were better in physically active groups besides body image (p = 0.003) for the survivors with breast-conserving surgery. However, moderate and marked activities did not further improve QoL than regular activity. CONCLUSION: Physicians and care-givers have to pay attention to inactive survivors to boost their physical activity, thereby facilitating a better QoL and dietary habit.

4,4'-Diaminodiphenyl Sulfone (DDS) as an Inflammasome Competitor.

The aim of this study is to examine the use of an inflammasome competitor as a preventative agent. Coronaviruses have zoonotic potential due to the adaptability of their S protein to bind receptors of other species, most notably demonstrated by SARS-CoV. The binding of SARS-CoV-2 to TLR (Toll-like receptor) causes the release of pro-IL-1ß, which is cleaved by caspase-1, followed by the formation and activation of the inflammasome, which is a mediator of lung inflammation, fever, and fibrosis. The NLRP3 (NACHT, LRR and PYD domains-containing protein 3) inflammasome is implicated in a variety of human diseases including Alzheimer's disease (AD), prion diseases, type 2 diabetes, and numerous infectious diseases. By examining the use of 4,4'-diaminodiphenyl sulfone (DDS) in the treatment of patients with Hansen's disease, also diagnosed as Alzheimer's disease, this study demonstrates the diverse mechanisms involved in the activation of inflammasomes. TLRs, due to genetic polymorphisms, can alter the immune response to a wide variety of microbial ligands, including viruses. In particular, TLR2Arg677Trp was reported to be exclusively present in Korean patients with lepromatous leprosy (LL). Previously, mutation of the intracellular domain of TLR2 has demonstrated its role in determining the susceptibility to LL, though LL was successfully treated using a combination of DDS with rifampicin and clofazimine. Of the three tested antibiotics, DDS was effective in the molecular regulation of NLRP3 inflammasome activators that are important in mild cognitive impairment (MCI), Parkinson's disease (PD), and AD. The specific targeting of NLRP3 itself or up-/downstream factors of the NLRP3 inflammasome by DDS may be responsible for its observed preventive effects, functioning as a competitor.

Density functional tight binding study of ß-Ga2O3: Electronic structure, surface energy, and native point defects.

A new parameter set to model monoclinic gallium oxide, ß-Ga2O3, with the density functional tight binding (DFTB) method is developed. Using this new parameter set, DFTB calculations of bulk electronic band structure, surface energy of low-index surfaces, and formation energy of native point vacancy defects are performed and compared with the state-of-the-art density functional theory (DFT) calculations using the advanced hybrid exchange correlation functional. DFTB calculates the bandgap energy of 4.87 eV around the Fermi energy with the conduction band approximately following the DFT study by Peelaers and Van de Walle [Phys. Status Solidi B 252, 828 (2015)]. The surface energies calculated feature the correct order of stability among low index surfaces with surface energies in semiquantitative agreement with Bermudez' report [Chem. Phys. 323, 193 (2006)]. Oxygen and gallium vacancy defect formation energies and respective transition levels calculated using DFTB with a new parameter set are in semiquantitative agreement with the previous DFT reports by Varley et al. and Zacherle et al. [Appl. Phys. Lett. 97, 142106 (2010); Phys. Rev. B 87, 235206 (2013)]. This new semiempirical parameter set for ß-Ga2O3, validated in bulk, surface, and point properties, would be useful for large spatiotemporal quantum chemical calculations regarding ß-Ga2O3.

Questionnaire study of the dietary habits of breast cancer survivors and their relationship to quality of life (KROG 14-09).

We evaluated the dietary habits of breast cancer survivors and investigated the relationship with quality of life (QoL), with 1,156 survivors recruited from 17 institutions. We used the Questionnaire Survey of Dietary Habits of Korean Adults (Q-DH-KOR) comprising 25 questions. The following indices were derived as follows: (1) quality of healthy dietary habits (Q-HD)-eight questions on number of meals, regularity, quantity, duration, skipping breakfast, dinner with companion(s), overeating and late-night snacks; (2) habits of nutritional balance (H-NB)-questions on consuming five food categories (grains, fruits, proteins, vegetables and dairy products); and (3) habits of unhealthy foods (H-UF)-questions on consuming three food categories (fatty, instant and fast foods). The times and regularity of meals, frequency of skipping breakfast, dinner with companion(s) and overeating were better in groups with high symptomatic and functional QoL. Symptomatic QoL positively affected Q-HD and H-NB (p < 0.001 and p = 0.024 respectively) and negatively affected H-UF (p = 0.02). Breast cancer survivors more frequently ate from the fruit, protein and vegetable categories than did the control group, with lower H-UF and higher Q-HD values (p < 0.001 and p < 0.001 respectively). Our findings supported the relationship between QoL and dietary habit and showed healthier dietary habits of breast cancer survivors than controls.

Genomic insights into Staphylococcus equorum KS1039 as a potential starter culture for the fermentation of high-salt foods.

BACKGROUND: Our previous comparative genomic analysis of Staphylococcus equorum KS1039 with five S. equorum strains illuminated the genomic basis of its safety and salt tolerance. However, a comprehensive picture of the cellular components and metabolic pathways involved in the degradation of macromolecules and development of sensory properties has not been obtained for S. equorum. Therefore, in this study, we examined the general metabolism of S. equorum based on information obtained from published complete genome sequences of six S. equorum strains isolated from different niches. Additionally, the utility of strain KS1039 as a starter culture for high-salt food fermentations was examined. RESULTS: All six S. equorum strains contained genes involved in glycolysis, the tricarboxylic acid cycle, and amino acid metabolic pathways, as well as color development. Moreover, the strains had the potential to produce acetoin, butanediol, and branched chain fatty acids, all of which are important flavor compounds. None of the strains contained decarboxylase genes, which are required for histamine and tyramine production. Strain KS1039 contained bacteriocin and CRISPR/Cas gene clusters, and experimental results suggested that these genes were functional in vitro. CONCLUSIONS: The comparative genomic analysis carried out herein provides important information on the usefulness of S. equorum KS1039 as a starter culture for the fermentation of high-salt foods in terms of safety, salt tolerance, bacteriocin production, and foreign plasmid restriction.

Lentibacillus alimentarius sp. nov., isolated from Myeolchi-jeotgal, a traditional Korean high-salt fermented anchovy.

A Gram-positive, motile, endospore-forming, rod-shaped bacterium, designated strain M2024T, was isolated from Myeolchi-jeotgal, a traditional Korean high-salt fermented anchovy and was characterised using a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence analysis showed that strain M2024T belongs to the genus Lentibacillus in the family Bacillaceae of the Firmicutes. The 16S rRNA gene sequence analysis showed that strain M2024T is closely related to Lentibacillus populi WD4L-1T (95.5%), Lentibacillus garicola SL-MJ1T (95.2%) and Virgibacillus siamensis MS3-4T (95.1%). The chemotaxonomic properties of strain M2024T are consistent with those of members of the genus Lentibacillus: the quinone system has MK-7 as the predominant menaquinone and anteiso-C15:0 and anteiso-C17:0 are the predominant cellular fatty acids. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The G+C content of the genomic DNA was determined to be 36.2 mol%. Differential phenotypic properties compared with closely related type strains support the conclusion that strain M2024T can be separated from previously described members of the genus Lentibacillus. The strain thus represents a novel species in this genus, for which the name Lentibacillus alimentarius sp. nov. is proposed. The type strain is M2024T (= KEMB 9001-124T = JCM 16521T).

BST106 Protects against Cartilage Damage by Inhibition of Apoptosis and Enhancement of Autophagy in Osteoarthritic Rats.

Chrysanthemum zawadskii var. latilobum (CZ) has been used as a traditional medicine in Asian countries for the treatment of inflammatory diseases. Recently, CZ extract was shown to inhibit differentiation of osteoclasts and provide protection against rheumatoid arthritis. The aim of this study was to investigate the molecular mechanisms of BST106, the ethanol extract of CZ, for cartilage protection in monosodium iodoacetate (MIA)-induced osteoarthritis (OA), particularly focusing on apoptosis and autophagy. BST106 (50, 100, and 200 mg/kg) was orally administered once daily to MIA-induced OA rats. Swelling, limping, roentgenography, and histomorphological changes were assessed 28 d after MIA injection. Biochemical parameters for matrix metalloproteinase (MMP), apoptosis, and autophagy were also assessed. BST106 ameliorated the severity of swelling and limping after MIA injection. Roentgenographic and histomorphological examinations revealed that BST106 reduced MIA-induced cartilage damage. BST106 decreased MIA-induced increases in MMP-2 and MMP-13 mRNA levels. Increased levels of serum cartilage oligomeric matrix protein and glycosaminoglycan release were attenuated by BST106. Furthermore, BST106 suppressed the protein expression of proapoptotic molecules and increased the protein expression of autophagosome- and autolysosome-related molecules. These findings indicate that BST106 protects against OA-induced cartilage damage by inhibition of the apoptotic pathway and restoration of impaired autophagic flux.

Virgibacillus jeotgali sp. nov., isolated from Myeolchi-jeotgal, a traditional Korean high-salt-fermented anchovy.

A Gram-staining-positive, motile, endospore-forming, rod-shaped bacterium, designated NS3012T, was isolated from Myeolchi-jeotgal, a traditional Korean high-salt-fermented anchovy and was characterized using a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence analysis showed that strain NS3012T belongs to the genus Virgibacillus in the family Bacillaceae of the phylum Firmicutes. The 16S rRNA gene sequence analysis showed that strain NS3012T was closely related to Virgibacillus halotolerans WS-4627T (98.1 %), Virgibacillus oceani MY11T (96.6 %) and Virgibacillus byunsanensis ISL-24T (96.5 %). The chemotaxonomic properties of strain NS3012T were consistent with those of the genus Virgibacillus: the quinone system with MK-7 as the predominant menaquinone and anteiso-C15 : 0 and anteiso C17 : 0 as the major cellular fatty acids; the cell-wall peptidoglycan type was based on meso-diaminopimelic acid. The major polar lipid was diphosphatidylglycerol. The G+C content of the genomic DNA was 36.8 mol%. On the basis of phylogenetic inference, and chemotaxonomic and other phenotypic properties, strain NS3012T is clearly differentiated from closely related species of the genus Virgibacillus and represents a novel species in this genus, for which the name Virgibacillus jeotgali sp. nov. is proposed. The type strain is NS3012T (=KEMB 9001-125T=JCM 16522T).

An assessment of quality of life for early phase after adjuvant radiotherapy in breast cancer survivors: a Korean multicenter survey (KROG 14-09).

BACKGROUNDS: Quality of life (QoL) has become a major concern as the survival time of breast cancer increases. We investigated the changes in QoL through comprehensive categorical analysis, for the first three years after breast cancer treatment including radiotherapy. METHODS: A total of 1156 patients were enrolled from 17 institutions. All survivors were grouped according to a surveillance period of 9-15 months (first year), 21-27 months (second year), and 33-39 months (third year) from the end of radiotherapy. The 5-dimensional questionnaire by the EuroQol group (EQ-5D) and the EORTC Quality of Life Questionnaire; breast cancer specific module (QLQ-BR23) were checked by self-administrated method. RESULTS: First, second and third year groups comprised 51.0, 28.9, and 21.0%. In EQ-5D-3 L (3-Likert scale) analysis, pain/discomfort and anxiety/depression categories showed lower QoL. In multivariate analyses of EQ-5D-VAS (visual-analogue scale), categories of pain/discomfort and self-care were improved with time; axillary dissection was a significant clinical factor deteriorates pain/discomfort, self-care and usual activities. In QLQ-BR23 analysis, the lowest scored category was sexual activity, followed by sexual enjoyment, future perspective, and hair loss, and the best scored category was breast symptoms. In multivariate analyses, arm symptoms, breast symptoms and body image were improved with time. CONCLUSIONS: Categories of pain/discomfort and self-care in EQ-5D-VAS, arm/breast symptoms and body image in QLQ-BR23 were improved, while categories of anxiety/depression and future perspective BR23 were not, suggesting necessity of psychosocial support. This research provides comprehensive information on the categorical aspects of QoL and changes during early follow-up after breast cancer treatment.

Oncologic Outcomes After Adjuvant Radiotherapy for Stage II Endometrial Carcinoma: A Korean Radiation Oncology Group Study (KROG 14-10).

OBJECTIVE: The aim of this study was to investigate the survival, patterns of failure, and prognostic factors in patients with stage II endometrial carcinoma treated with adjuvant radiotherapy. METHODS: We reviewed the medical records of patients who underwent total hysterectomy, bilateral salpingo-oophorectomy, and pelvic lymph node dissection followed by adjuvant radiotherapy in 10 participating hospitals of the Korean Radiation Oncology Group. Most patients received adjuvant external beam radiation therapy, with a median dose of 50.4 Gy; approximately 50% of these patients received an additional brachytherapy boost, with a median dose of 18 Gy. Adjuvant chemotherapy was administered to 19 patients. RESULTS: A total of 122 patients were examined. Over a median follow-up period of 62.7 months (range, 1.9-158.8 months), the 5-year overall survival (OS) and disease-free survival rates were found to be 91.1% and 85.1%, respectively. Recurrence was observed in 14 patients (11.5%), including 3 with local recurrence and 11 with distant metastases as the first site of recurrence. Univariate analysis indicated that lymphovascular invasion was related to an unfavorable OS. An age of 60 years or above, histologic grade 3, and lymphovascular invasion were identified as risk factors for OS. Because there were several risk factors related to OS, we assigned patients to a high-risk group (defined as cases with ≥1 risk factors) and a low-risk group. The 5-year OS rate of the high-risk group was significantly inferior to that of the low-risk group (82.9% vs 100%, P = 0.003). CONCLUSIONS: The high-risk group had a significantly poorer survival rate than the low-risk group, and distant metastasis was the main pattern of recurrence, thus indicating that further adjuvant chemotherapy should be considered in high-risk patients.

Safety assessment of Tetragenococcus halophilus isolates from doenjang, a Korean high-salt-fermented soybean paste.

We assessed the safety of 49 Tetragenococcus halophilus strains isolated from doenjang in Korea. Minimum inhibitory concentration assays showed that all strains can be considered as susceptible to ampicillin, erythromycin, penicillin G, tetracycline, and vancomycin, but resistant to ciprofloxacin based on the Enterococcus breakpoint values provided by the European Committee on Antimicrobial Susceptibility testing in 2015. Ciprofloxacin resistance was sufficiently high to consider the potential for acquisition of transmissible determinants. Two strains exhibiting potentially acquired resistance to chloramphenicol and gentamicin, and chloramphenicol alone, were identified. None of the strains exhibited α-hemolytic activity or biofilm formation; two strains exhibited weak ß-hemolytic activity. Doenjang isolates produced an average of 3338.6 ppm of tyramine in the laboratory, considerably higher than the levels produced by two reference strains. All of the test strains exhibited similar cadaverine, histamine, and putrescine production patterns. Most T. halophilus strains could grow at a NaCl concentration >18%, exhibited acid production at 15% NaCl, and expressed strain-specific protease and lipase activities. The potential acquisition of transmissible determinants for antibiotic resistance and tyramine production identified in this study necessitate the need for a thorough safety assessment of T. halophilus before it can be considered for use in food fermentation processes.