• Journal of Environmental Health Sciences
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• v.47 no.2
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• pp.155-165
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• 2021

Objectives: Acute exposure to high concentrations of chemicals can occur when a chemical accident takes place. As such exposure can cause ongoing environmental pollution, such as in the soil and groundwater, there is a need for a tool that can assess health effects in the long term. The purpose of this study was assessing the health risks of residents living near a chemical accident site due to long-term exposure while considering the temporal concentration changes of the toxic chemicals leaked during the accident until their extinction in the environment using a multimedia environmental dynamics model. Methods: A health risk assessment was conducted on three cases of formaldehyde chemical accidents. In this study, health risk assessment was performed using a multimedia environmental dynamics model that considers the behavior of the atmosphere, soil, and water. In addition, the extinction period of formaldehyde in the environment was regarded as extinction in the environment when the concentration in the air and soil fell below the background concentration prior to the accident. The subjects of health risk assessment were classified into four groups according to age: 0-9 years old, 10-18 years old, 19-64 years old, and over 65 years old. Carcinogenic risk assessment by respiratory exposure and non-carcinogenic risk assessment by soil intake were conducted as well. Results: In the assessment of carcinogenic risk due to respiratory exposure, the excess carcinogenic risk did not exceed 1.0×10-6 in all three chemical accidents, so there was no health effect due to the formaldehyde chemical accident. As a result of the evaluation of non-carcinogenic risk due to soil intake, none of the three chemical accidents had a risk index of 1, so there was no health effect. For all three chemical accidents, the excess cancer risk and hazard index were the highest in the age group 0-9. Next, 10-18 years old, 65 years old or older, and 19-64 years old showed the highest risk. Conclusion: This study considers environmental changes after a chemical accident occurs and until the substance disappears from the environment. It also conducts a health risk assessment by reflecting the characteristics of the long-term persistence and concentration change over time. It is thought that it is of significance as a health risk assessment study reflecting the exposure characteristics of the accident substance for an actual chemical accident.

• Smart Structures and Systems
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• v.31 no.3
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• pp.247-257
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• 2023

In structural health monitoring of large-scale structures, optimal sensor placement plays an important role because of the high cost of sensors and their supporting instruments, as well as the burden of data transmission and storage. In this study, a vibration sensor placement algorithm based on deep reinforcement learning (DRL) is proposed, which can effectively solve non-convex, high-dimensional, and discrete combinatorial sensor placement optimization problems. An objective function is constructed to estimate the quality of a specific vibration sensor placement scheme according to the modal assurance criterion (MAC). Using this objective function, a DRL-based algorithm is presented to determine the optimal vibration sensor placement scheme. Subsequently, we transform the sensor optimal placement process into a Markov decision process and employ a DRL-based optimization algorithm to maximize the objective function for optimal sensor placement. To illustrate the applicability of the proposed method, two examples are presented: a 10-story braced frame and a sea-crossing bridge model. A comparison study is also performed with a genetic algorithm and particle swarm algorithm. The proposed DRL-based algorithm can effectively solve the discrete combinatorial optimization problem for vibration sensor placements and can produce superior performance compared with the other two existing methods.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.819-823
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• 2014

Objective: The aim was to evaluate roles of vitamin D3 (VD3) and beta-carotene (BC) in the development of esophageal squamous cell carcinoma (ESCC) in a high-risk area, Huai'an District, Huai'an City, China. Methods: 100 new ESCC diagnosed cases from 2007 to 2008 and 200 residency- age-, and sex-matched healthy controls were recruited. Data were collected from questionnaires, including a food frequency questionnaire (FFQ) to calculate the BC intake, and reversed phase high-performance liquid chromatography (RP-HPLC) was used to measure the serum concentrations of BC and VD3. Odds ratios (OR) and 95% confidence intervals (CI) were calculated in conditional logistic regression models. Results: The average dietary intake of BC was $3322.9{\mu}g$ (2032.4-5734.3) in the case group and $3626.8{\mu}g$ (1961.9-5827.9) in control group per capita per day with no significant difference by Wilcoxon test (p>0.05). However, the levels of VD3 and BC in the case group were significantly lower than in the control group (p<0.05). The OR values of the highest quartile and the lowest quartile of VD3 and BC in serum samples were both 0.13. Conclusion: Our results add to the evidence that high circulating levels of VD3 and BC are associated with a reduced risk of ESCC in this Chinese population.

• Journal of Korean society of Dental Hygiene
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• v.14 no.2
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• pp.269-279
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• 2014

Objectives : The purpose of this study was to investigate the oral health center operation and to activate the program development of public oral health center. Methods : Delphi analyses were utilized by the recruited expert panel from August to September in 2012. Results : The difficulty in operation of the oral health centers is the human resources management. In order to solve the human resources operation, utilization of the local human resources is the best choice of the solution. The next choice was the designation of the oral health expert in Ministry of Health and Welfare. So the expert can activate the public oral health care system for the disabled and the underprivileged classes in the long term. Conclusions : In order to activate the oral health centers, Ministry of Health and Welfare should promote the public health center function connected with the cooperation of the Association of dental hygienists.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4477-4481
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• 2016

Purpose: To compare the relative merits of imatinib and allogeneic hematopoietic stem cell transplantation (allo-HSCT) for chronic myelogenous leukemia (CML). Materials and Methods: This cohort study was designed to compare the outcomes of imatinib (n=292) versus allo-HSCT (n=141) for CML, the clinical data of these patients being retrospectively analyzed so as to compare the event free survival (EFS) and overall survival (OS) between these two groups with patients in the chronic phase (CP) and advanced phases, including accelerate (AP) and blast phases (BP). Results: (1) Patients treated with imatinib (278 in the CP) demonstrated superior EFS, OS, 5-year EFS and 5-year OS rates of 88.5% versus 70.0% (P<0.05), 93.2% versus 80.0% (P<0.05), 84% versus 75.0% (P<0.05) and 92% versus 79.0% (P<0.05), respectively, to those treated with allo-HSCT (120 patients in the CP). (2) Both treatments resulted in similar survival, with EFS and OS rates of 42.9% versus 47.6% (P>0.05), 42.9% versus 57.1% (P> 0.05), respectively, for imatinib (14 patients in the AP and BP) and allo-HSCT (21 patients in the AP and BP). Conclusions: Imatinib confers significant survival advantage (EFS and OS) for CML patients with CP compared with allo-HSCT treatment. However, the outcomes are equally good with both treatments in AP and BP patients.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5455-5461
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• 2012

Luteolin is a plant flavonoid which exhibits anti-oxidative, anti-inflammatory and anti-tumor effects. However, the antiproliferative potential of luteolin is not fully understood. In this study, we investigated the effect of luteolin on cell cycling and apoptosis in human esophageal squamous carcinoma cell line Eca109 cells. MTT assays showed that luteolin had obvious cytotoxicity on Eca109 with an $IC_{50}$ of $70.7{\pm}1.72{\mu}M$ at 24h. Luteolin arrested cell cycle progression in the G0/G1 phase and prevented entry into S phase in a dose- and time-dependent manner. as assessed by FCM. Luteolin induced apoptosis of Eca109 cells was demonstrated by AO/EB staining assay and annexin V-FITC/PI staining. Moreover, luteolin downregulated the expression of cyclin D1, survivin and c-myc, and it also upregulated the expression of p53, in line with the fact that luteolin was able to inhibit Eca109 cell proliferation.

• Smart Structures and Systems
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• v.21 no.5
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• pp.695-703
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• 2018

Based on monitoring data collected from the Nanjing Dashengguan Bridge over the last five years, this paper systematically investigates the effects of temperature field and train loadings on the structural responses of this long-span high-speed railway bridge, and establishes the early warning thresholds for various structural responses. Then, some lessons drawn from the structural health monitoring system of this bridge are summarized. The main context includes: (1) Polynomial regression models are established for monitoring temperature effects on modal frequencies of the main girder and hangers, longitudinal displacements of the bearings, and static strains of the truss members; (2) The correlation between structural vibration accelerations and train speeds is investigated, focusing on the resonance characteristics of the bridge at the specific train speeds; (3) With regard to various static and dynamic responses of the bridge, early warning thresholds are established by using mean control chart analysis and probabilistic analysis; (4) Two lessons are drawn from the experiences in the bridge operation, which involves the lacks of the health monitoring for telescopic devices on the beam-end and bolt fractures in key members of the main truss.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4084-4092
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• 2012

Theoretical calculations based on density functional theory (DFT) were performed to study the substituent effect on the geometric and electronic structures as well as the biological behavior of technetium-99m-labeled diphosphonate complexes. Optimized structures of these complexes are surrounded by six ligands in an octahedral environment with three unpaired 4d electrons ($d^3$ state) and the optimized geometry of $^{99m}Tc$-MDP agrees with experimental data. With the increase of electron-donating substituent or tether between phosphate groups, the energy gap between frontier orbitals increases and the probability of non-radiative deactivation via d-d electron transfer decreases. The charge distribution reflects a significant ligand-to-metal electron donation. Based on the calculated geometric and electronic structures and biologic properties of $^{99m}Tc$-diphosphonate complexes, several structure-activity relationships (SARs) were established. These results may be instructive for the design and synthesis of novel $^{99m}Tc$-diphosphonate bone imaging agent and other $^{99m}Tc$-based radiopharmaceuticals.

• The Journal of Korean Medicine
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• v.35 no.3
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• pp.135-154
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• 2014

Purpose: There is an issue in applying various principles introduced in established Korean medical classics to "Pharmaceuticals Approval, Notification and Review" of "herbal medicinal preparations" and "new drugs from natural products" that are used for western forms of medical treatment. Thus, an analysis of the origin, purpose, and application of established Korean medical classics in the Korean Pharmaceutical Affairs Act is essential. Methods: We collected data regarding the origin, purpose, and application of established Korean medical classics in the Korean Pharmaceutical Affairs Act, and classified them by periodical change and subjects. Results: Established Korean medical classics are applied as follows: 1) as criteria for Korean medicine distributors' sales of mixed herbal drugs (Pharmaceutical Affairs Act; since 1953), 2) as official compendiums for pharmacists' preparation of Korean medicine (Ministry of Health and Welfare's authoritative interpretation; from early 1970s to 1993), 3) as standards for oriental pharmacists' quality measurement of preparations (notification of the Ministry of Health and Welfare; since 1995), 4) as criteria for "Pharmaceuticals Approval, Notification and Review" of herbal medicinal preparations and crude drug preparations (notifications regarding drug approval process by the Ministry of Health and Welfare and the Ministry of Food and Drug Safety; since 1978), and 5) as standards for the quality of materials of health functional food (from 2004 to 2011). Conclusion: The application of Korean medical classics has been closely related with the change of the laws, regulations, and systems that are relevant to Korean medicine, and it seems to be more favorable for pharmacists than oriental pharmacists. Meanwhile, regulations that apply prescriptions that are recorded in Korean medical classics - dosage, indications, and preparation methods - as criteria for the approval of crude drug preparations for western medical treatment should be abolished.

• Parasites, Hosts and Diseases
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• v.50 no.4
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• pp.379-384
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• 2012

Resistance of Plasmodium spp. to anti-malarial drugs is the primary obstacle in the fight against malaria, and molecular markers for the drug resistance have been applied as an adjunct in the surveillance of the resistance. In this study, we investigated the prevalence of mutations in pvmdr1, pvcrt-o, pvdhfr, and pvdhps genes in temperate-zone P. vivax parasites from central China. A total of 26 isolates were selected, including 8 which were previously shown to have a lower susceptibility to chloroquine in vitro. For pvmdr1, pvcrt-o, and pvdhps genes, no resistance-conferring mutations were discovered. However, a highly prevalent (69.2%), single-point mutation (S117N) was found in pvdhfr gene. In addition, tandem repeat polymorphisms existed in pvdhfr and pvdhps genes, which warranted further studies in relation to the parasite resistance to antifolate drugs. The study further suggests that P. vivax populations in central China may still be relatively susceptible to chloroquine and sulfadoxine-pyrimethamine.