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Aim This study was done to determine the effects of temperature, pH and sodium chloride (NaCl) on antimicrobial activity of magnesium oxide (MgO) nanoparticles (NPs) against E. coli O157:H7. Methods and results Culture conditions were established by varying the pH (5.0, 7.2 and 9.0), NaCl concentration (0.5, 2.0, 3.5 and 5.0%, w/v), and incubation temperatures (4, 12, 22 and 37°C). At each condition, the antimicrobial activities of MgO-NPs (0, 1, 2 and 4 mg/ml) against E. coli O157:H7 were measured. Four-way analysis of variance indicated interactions among all factors had a significant effect (p ≤ 0.05) on the antimicrobial activity of MgO-NPs. The concentration of MgO-NPs necessary to cause a 5-log reduction of E. coli O157:H7 under the most inhibitory conditions (37°C, pH 9.0, and 5.0% NaCl) was 0.50 mg/ml of MgO-NPs. Conclusion The antimicrobial activity of the MgO-NPs increased significantly (p ≤ 0.05) with increased temperature, pH and NaCl concentration in TSB. Significance and impact of the study The influence of intrinsic and extrinsic factors on antimicrobial activity of MgO-NPs we found will contribute to the development of microbial decontamination strategies using MgO in the food industry.

Background We determined the clinical characteristics and predictive factors of long-term response to pemetrexed maintenance therapy as first-line treatment for non-small cell lung cancer (NSCLC). Methods A total of 950 advanced NSCLC patients received pemetrexed (500 mg/m2 ) plus cisplatin (60 mg/m2 ) (Pem-Cis) induction chemotherapy every three weeks as first-line treatment between January 2010 and August 2018. Patients who did not show progression after four cycles of Pem-Cis and received at least one cycle of pemetrexed maintenance were recruited (n = 199). Results Patients were divided into subgroups according to total cycles of pemetrexed: ≤ 10 (F10, n = 134) and > 10 (M10, n = 65). The M10 group had a higher proportion of patients with stage M1a (intrathoracic metastasis alone) and exhibited lower levels of thymidylate synthase (TS) than the F10 group (median H-score 10.0% vs. 60.0%; P = 0.031). Further subgrouping identified extreme responders: ≤ 7 (F7, n = 101) and ≥ 20 (M20, n = 26) cycles. The M20 group showed lower mean serum CEA levels before (17.5 vs. 147.0; P = 0.099) and after (6.9 vs. 53.2; P = 0.001) Pem-Cis treatment, and a higher incidence of normalization after Pem-Cis (abnormal 41.7% vs. 68.5%; P = 0.015). M1a stage, normalization of CEA levels after Pem-Cis, and lower TS H-score were predictors of progression-free survival in patients administered pemetrexed maintenance. Conclusion M1a stage and lower TS expression were predictors of long-term response to pemetrexed maintenance. CEA normalization after Pem-Cis could be an additional surrogate marker of positive response to long-term treatment.

Background: There are many models for predicting diabetes mellitus (DM), but their clinical implication remains vague. Therefore, we aimed to create various DM prediction models using easily accessible health screening test parameters.Methods: Two sets of variables were used to develop eight DM prediction models. One set comprised 62 easily accessible examination results of commonly used variables from a tertiary university hospital. The second set comprised 27 of the 62 variables included in the national routine health checkups. Gradient boosting and random forest algorithms were used to develop the models. Internal validation was performed using the stratified 10-fold cross-validation method.Results: The area under the receiver operating characteristic curve (ROC-AUC) for the 62-variable DM model making 12-month predictions for subjects without diabetes was the largest (0.928) among those of the eight DM prediction models. The ROC-AUC dropped by more than 0.04 when training with the simplified 27-variable set but still showed fairly good performance with ROC-AUCs between 0.842 and 0.880. The accuracy was up to 11.5% higher (from 0.807 to 0.714) when fasting glucose was included.Conclusion: We created easily applicable diabetes prediction models that deliver good performance using parameters commonly assessed during tertiary university hospital and national routine health checkups. We plan to perform prospective external validation, hoping that the developed DM prediction models will be widely used in clinical practice.

The objective of this paper is to examine the characteristics of leaked-gas dispersion in ship-to-ship liquefied natural gas (LNG) bunkering, thereby providing an insight towards determining the appropriate level of safety zones. For this purpose, parametric studies are undertaken in various operational and environmental conditions, with varying geometry of the ships, gas leak rate, wind speed and wind direction. The study applies computational fluid dynamics (CFD) simulations for case-specific scenarios where a hypothetical LNG bunkering ship with a capacity of 5100 m3 in tank space is considered to refuel two typical types of large ocean-going vessels: an 18,000 TEU container ship and a 319,000 DWT very large crude oil carrier. It is found that wind speed, wind direction, ship geometry and loading condition are important parameters affecting the extent of safety zones in addition to gas leak rate and leak duration. Details of the computations and discussions are presented.

Background: Circulating tumor cells (CTCs) have potential to provide minimally invasive way for the response monitoring of various cancer. This study aimed to investigate the feasibility of CTCs as a predictive marker for anti-PD-L1 immunotherapy in patients with advanced non-small cell lung cancer (NSCLC). Methods: This study included 37 patients with advanced NSCLC receiving atezolizumab monotherapy as second-line or more from July to November 2019. Blood was collected in a K2-EDTA tube and CTCs were isolated and enriched by using CD-PRIMETM system which is antibody-independent size-based isolation method. By Bioview CCBS system, total CTCs (tCTCs) were identified by a sum of single EpCAM/CK-positive (sCTCs) and double EpCAM/CK-CD45-positive cells (dCTCs). Results: Among 26 response-evaluable patients, objective response rate (ORR) and disease control rate (DCR) were 11.5% (3/26) and 57.7% (15/26), respectively. At cycle 1 (C1), patients with progression (PD) showed higher sCTC count (median, 8.6 vs. 4.3, p=0.065) and sCTC-to-tCTC ratio (median %, 35.9 vs. 9.8, p=0.024) than those without PD. During treatment, tCTC and sCTC count showed significant increase from C1 to C2 (p=0.019 and p=0.022). The subgroup with high sCTC increase from C1 to C2 (more than 2-folds) showed higher DCR than subgroup with low sCTC increase (less than 2-folds) (88.9% vs. 44.4%, p=0.066). Patients with high sCTC-to-tCTC ratio at C1 showed worse progression-free survival (median, 2.1 months) than those with low sCTC-to-tCTC ratio (not reached, hazard ratio 2.87, 95% confidence interval: 1.06-7.75, p=0.082). Conclusion: The baseline sCTC count and sCTC increase (more than 2-folds) at the first 3-week after atezolizumab could be potential biomarkers to predict the disease progression and poor survival in advanced NSCLC. Citation Format: Cheol-Kyu Park, Joon-Young Yoon, Min-Suk Kim, Bo-Gun Koh, Hyun-Ju Cho, In-Jae Oh, Young-Chul Kim. Circulating tumor cell as a predictive marker for immunotherapy in advnaced non-small cell lung cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5373.

This work is motivated by the need to identify the fire and explosion risk on liquefied natural gas carriers (LNGCs) developed by Daewoo Shipbuilding & Marine Engineering Co., Ltd., because the main engines are designed to use highly pressurized natural gas (about 300 bar), which has caused vague fears of fire and explosion risks. In this context, to identify the risk of fires and explosions quantitatively, a fire and explosion risk analysis (FERA) was carried out for the LNGCs. This paper, as a part of the FERA, presents the results of a preliminary investigation on the effect of introducing the highly pressured fuel gas system into LNGCs on the fire and explosion risk especially in the cargo compressor room. This study is conducted in a comparative way considering the risk contribution of each parameter that could impact on the fire and explosion risk. The effect of the highly pressured fuel gas is indirectly taken into account by the change of the initial leak rate in the system. To identify effects of the considered parameters quantitatively, dozens of simulations for the selected gas dispersion, explosion, and fire scenarios were carried out using FLACS and KFX. Based on the simulation results, it is concluded that, in case of the LNGCs, the effects of the initial large leak rate due to the high pressure in the fuel gas pipes on the fire and explosion risk are not significant compared with the effects of other parameters such as leak amount, leak location, and leak direction.

Rationale Influenza is an infection caused by the influenza virus, and its symptoms are mostly mild and self-limiting. However, influenza can cause severe or fatal complications in high-risk patients. Although tracheobronchitis is one of the common complications of influenza, necrotizing tracheobronchitis is very rare. Herein, we describe a case of necrotizing tracheobronchitis causing airway obstruction complicated by pandemic 2009 H1N1 influenza. Patient concerns A 60-year-old man presented with fever and dyspnea. On arrival at the emergency room (ER), the patient received oxygen 4 L/minute via a nasal prolong owing to mild hypoxemia. And invasive mechanical ventilation was needed 5 hours after arrival at the ER due to progressive hypoxemia. Diagnoses Fiberoptic bronchoscopy was performed owing to bloody secretion in the endotracheal tube and revealed diffuse tracheobronchitis with necrotic and hemorrhagic materials obstructing the trachea and bronchus. The pandemic 2009 H1N1 influenza virus was detected from the bronchial washing sample; no other microorganism was detected. Intervention He received peramivir plus oseltamivir and broad-spectrum antibiotics. Outcomes The bloody secretion continued. He developed cardiac arrest due to airway obstruction on the 6th day of admission. After cardiac arrest, his condition progressed to multi-organ failure, and the patient died on the 10th day of admission. Lessons We suggest that necrotizing tracheobronchitis be considered in patients with influenza who present with unexplained hypoxemia.

In this paper, we report the synthesis of silicon oxide nanowire-embedded silicon (SONW-Si) nanocrystals (NCs) and their light emission characteristics. The SONW-Si NCs were formed by thermally annealing silicon-rich oxide nanowires (NWs) grown at low temperatures. The well-defined Si NCs were found to have grown in (111) direction and clearly displayed a higher density distribution at the center of the NWs. Photoluminescence (PL) measurements of the SONW-Si NCs showed an enhanced PL intensity compared to the silicon oxide film-embedded Si NCs, which may be related to the difference between the Si diffusion characteristics of SiO_x NWs and films.

This work is motivated by the need to identify the fire and explosion risk on LNGCs developed by Daewoo Shipbuilding & Marine Engineering Co., Ltd. (DSME) because the main engines are designed to use highly pressurized natural gas (about 300 bar), which has caused vague fears of fire and explosion risks. In this context, to identify the risk of fires and explosions quantitatively caused by ignitions of unintended leaked gas from fuel gas lines, a FERA was carried out for the LNGCs [1]. This paper, as a part of the FERA, presents the results of a preliminary investigation on the effect of introducing the highly pressured fuel gas system into LNGCs on the fire and explosion risk especially in the cargo compressor room. This study is conducted in a comparative way considering the risk contribution of each parameter that could impact on the fire and explosion risk in LNGCs. The effect of the highly pressured fuel gas is indirectly taken into account by the change of the initial leak rate in the system. To identify effects of the considered parameters quantitatively, dozens of simulations for the selected gas dispersion, explosion and fire scenarios were carried out using FLACS and KFX. Based on the results from the simulations, it is concluded that, in case of the LNGCs, the effects of the initial large leak rate due to the high pressure in the fuel gas pipes on fire and explosion risk are not significant compared with the other parameters’ effects.

In this work we report on the photoluminescence (PL) characteristics of porous silicon (PS) prepared by electrochemical anodization of a p-type Si wafer using chemically metal-dissolved hydrofluoric solutions. Various solid metals, oxidative (Al, Fe, Sn, Ni, Cr) and reductive (Cu), were used for this work. The effects of metals on the PL properties in as-grown, illuminated, and aged states have been studied. It is found that for the as-grown state the PL intensity is reduced by the addition of metal. In particular, the Cu-doped PS reveals a PL intensity lower by one order of magnitude as compared to that of normal PS. The improvement of stability in the PL intensity under illumination was only observed for the Cu-doped PS sample, which is more stable by a factor of 2 as compared to that of normal PS. On the other hand, the improved stability of the PL intensity in the aged state was observed for metal-doped PS samples other than for the Cu-doped sample. From the results, it is suggested that reductive metals are more effective in reducing the PL degradation caused by illumination while oxidative metals are more effective in reducing the PL degradation caused by ageing.

The aim of this paper is to examine the effect of wind on the thermal diffusion characteristics of floating production storage and offloading (FSPO) topside models subject to fire. It is motivated by the need to identify the fire loads on FPSO topsides, taking into account the effects of wind speed and direction. The results of an experimental and numerical study undertaken for these purposes are reported here. This paper is part of Phase II of the joint industry project on explosion and fire engineering of FPSOs (EFEF JIP) [1]. An experiment was performed on a 1/14-scale FPSO topside model using a wind tunnel test facility. The locations of the heat source of the fire were varied, as were the speed and direction of the wind, and the temperature distribution was measured. Computational fluid dynamics (CFD) simulations using the ANSYS CFX program were performed on the test model, with the results obtained compared with the experimental results. It is concluded that wind has a significant effect on the thermal diffusion characteristics of the test model and that the CFD simulations are in good agreement with the experimental results. The insights developed in this study will be very useful for the fire engineering of FPSO topsides.Copyright © 2010 by ASME