• KSBB Journal
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• v.29 no.3
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• pp.188-192
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• 2014

Calcite forming bacteria (CFB) have been received increasing attention as a novel and environmental friendly strategy for the healing of concrete crack. Among the CFB, spore forming bacteria were proposed to overcome concrete condition (high pH, hydration heat, deicer). In this study, Lysinibaclillus sphaericus WJ-8 (WJ-8) isolated from concrete pavement was characterized. The WJ-8 was able to precipitate calcite at 10 mg/mL. When observed by scanning electron microscopy, WJ-8 showed spore formation and maximum spore yield was approximately 97.9%. Also response of spores against various environment stresses was examined. Approximately 83~97% of spores maintained their survivability at each three conditions ($60^{\circ}C$, 3 M NaCl and pH 12).

• Journal of Environmental Science International
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• v.12 no.11
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• pp.1189-1196
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• 2003

The effect of boron and aluminum on the development of adventitious roots was studied in sunflower cuttings. Three-day-old seedlings were de-rooted and grown in nutrient solutions with or without boron and supplemented with different concentrations (from 50 to 700 ${\mu}$M) of aluminum. The number and length of the adventitious roots and proline content in adventitious roots in response to insufficient boron and aluminum stress were determined periodically. The micronutrient boron caused the development of numerous roots in the lower parts of the hypocotyl. A dose-response of boron-induced rooting yielded an optimum concentration of 0.1 mM boron. In the absence of boron, in the majority of the adventitious roots, a significant inhibition was observed with or without aluminum, indicating that the most apparent symptom of boron deficiency is the cessation of root growth. Increasing concentrations of aluminum caused progressive inhibition of growth and rooting of the hypocotyls, and a parallel increase in proline levels of adventitious roots. Supplemental boron ameliorated the inhibitory effect of aluminum, suggesting that aluminum could inhibit root growth by inducing boron deficiency. Ascorbate added to medium in the absence of boron improved root growth and induced a significant decrease in proline levels. These findings suggest that adventitious root growth inhibition resulting from either boron deficiency or aluminum toxicity may be a result of impaired ascorbate metabolism.

• Clinical and Experimental Vaccine Research
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• v.13 no.4
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• pp.271-300
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• 2024

Vaccination is a cornerstone of public health, saving millions of lives each year by preventing a variety of infectious diseases. Yet, despite global vaccination efforts, emerging research highlights significant geographical disparities in vaccine efficacy and immunogenicity. These variations underscore the critical interplay between immunological factors and environmental, genetic, and nutritional elements across different populations. Our review article aimed to explore the multifactorial reasons behind geographical variations in vaccine efficacy. Also, this study has shown how important host factors like age, obesity, gender, and genetic diversity, especially within the major histocompatibility complex, are in determining how well a vaccine works. Nutritional status, namely deficiencies in micronutrients such as vitamins and zinc, and lifestyle factors including stress, sleep, alcohol consumption, and physical activity are also shown to have profound effects on vaccine-induced immunity. Importantly, our paper also brought to light the influence of microbial and ecological factors, such as the gut microbiome and environmental pollutants, on the immune system's response to vaccination. The findings emphasize the importance of tailoring vaccination strategies to accommodate the unique immunological landscapes shaped by geographical and societal factors. This tailored approach could enhance vaccine efficacy, reduce disparities in vaccine response, and ultimately contribute to the global fight against infectious diseases.

• Advances in concrete construction
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• v.5 no.2
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• pp.117-143
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• 2017

The attack of environmental aggressive agents progressively reduces the structural reliability of buildings and infrastructures and, in the worst exposition conditions, may even lead to their collapse in the long period. A change in the material and sectional characteristics of a structural element, due to the environmental damaging effects, changes its mechanical behaviour and varies both the internal stress redistribution and the kinematics through which it reaches its ultimate state. To identify such a behaviour, the evolution of both the damaging process and its mechanical consequences have to be taken into account. This paper presents a computational approach for the analysis of reinforced and prestressed concrete elements under sustained loading conditions and subjected to given damaging scenarios. The effects of the diffusion of aggressive agents, of the onset and development of the corrosion state in the reinforcement and the corresponding mechanical response are studied. As known, the corrosion on the reinforcing bars influences the damaging rate in the cracking pattern evolution; hence, the damage development and the mechanical behaviours are considered as coupled phenomena. The reliability of such an approach is validated in modelling the diffusion of the aggressive agents and the changes in the mechanical response of simple structural elements whose experimental behaviour is reported in Literature. A second set of analyses studies the effects of the corrosion of the tendons of a P.C. beam and explores potentially unexpected structural responses caused by corrosion under different aggressive exposition. The role of the different types and of the different positions of the damaging agents is discussed. In particular, it is shown how the collapse mode of the beam may switch from flexural to shear type, in case corrosion is caused by a localized chloride attack in the shear span.

• BMB Reports
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• v.52 no.11
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• pp.665-670
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• 2019

Nucleotide-binding oligomerization domain protein 2 (NOD2), an intracellular pattern recognition receptor, plays important roles in inflammation and cell death. Previously, we have shown that NOD2 is expressed in vascular smooth muscle cells (VSMCs) and that NOD2 deficiency promotes VSMC proliferation, migration, and neointimal formation after vascular injury. However, its role in endoplasmic reticulum (ER) stress-induced cell death in VSMCs remains unclear. Thus, the objective of this study was to evaluate ER stress-induced viability of mouse primary VSMCs. NOD2 deficiency increased ER stress-induced cell death and expression levels of apoptosis mediators (cleaved caspase-3, Bax, and Bak) in VSMCs in the presence of tunicamycin (TM), an ER stress inducer. In contrast, ER stress-induced cell death and expression levels of apoptosis mediators (cleaved caspase-3, Bax, and Bak) were decreased in NOD2-overexpressed VSMCs. We found that the $IRE-1{\alpha}-XBP1$ pathway, one of unfolded protein response branches, was decreased in NOD2-deficient VSMCs and reversed in NOD2-overexpressed VSMCs in the presence of TM. Furthermore, NOD2 deficiency reduced the expression of XBP1 target genes such as GRP78, PDI-1, and Herpud1, thus improving cell survival. Taken together, these data suggest that the induction of ER stress through NOD2 expression can protect against TM-induced cell death in VSMCs. These results may contribute to a new paradigm in vascular homeostasis.

• Journal of the Korean GEO-environmental Society
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• v.14 no.6
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• pp.13-19
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• 2013

In this study, the target ground was selected for the assessment of liquefaction, for which energy-based Arias intensity liquefaction assessment method was applied, The results of evaluation by simplified method using conventional in-situ test were compared. The result of the assessment of liquefaction revealed that the safety factor of the Arias Intensity using the actual records of the Hachinohe and Ofunato earthquake showed generally similar trends with the simplified method, However, the Arias Intensity factor of safety for the artificial earthquake created from the design response spectrum showed some difference from the factors of safety of the simplified method. The shear stress ratio and the occurrence strength of the Arias Intensity are differently calculated between stress and energy, but the resistance stress ratio of the simplified method and the resistance strength of the Arias Intensity use the empirical chart of the results of the standard penetration test for the actual liquefaction areas by the earthquake, which seems the reason for the similar results between Arias Intensity assessment and stress concept simplified method for Hachinohe and Ofunato earthquakes. Therefore, it was found that the energy-based Arias Intensity liquefaction assessment could represent the dynamic changes of the ground caused by seismic characteristics such as acceleration, magnitude, duration and amplitude.

• Journal of Korean Academy of Nursing
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• v.25 no.4
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• pp.790-806
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• 1995

The present study examined the causal relationships among nurses' job environment /job characteristics(work overload, lack of autonomy, professional role conflict, interpersonal relationships), maturity, job stress, job satisfaction and turnover intention by constructing and testing a theoretial framework. Based on Katz and Kahn's (1978) theory of organizational open system and Kahn, Wolfe, Quinn, and Snoek's (1964) theory of stress, nurses' turnover intention, job satisfaction and job stress were conceived of as outcomes of the interplay between personal characteristics and work environment. Personal aspects associated with outcome variables included professional knowlege and skill, and maturity(challenge, commitment, control, responsibility). The work environment factors involved work overload, lack of autonomy, professional role conflict, and interpersonal relationships (social support). Three university hospitals located in Seoul were selected to participate. The total sample of 443 registered nurses represents a response rate of 96 percent. Linear structural relationships (LISREL) technique was used to test the fit of the proposed conceptual model to the data and to examine the causal relationships among variables. The result showed that both the proposed model and the modified model fit the data excellently, revealing considerable explanatinal power for job stress and job satisfaction. The explanatory power of turnover intention was relatively lower than those of stress and satisfaction. In predicting nurses' stress, satisfaction and turnover intention, the findings of this study clearly demonstrated that professional role conflict might be the most important variable of the all the environmental variables and personal characteristics. The results were dis-cussed, including directions for the future research and practical implications drawn from the research were suggested.

• Biomedical Science Letters
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• v.15 no.3
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• pp.249-255
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• 2009

All living things have been developed efficient strategies to cope with external and internal environmental changes via a process termed 'homeostasis'. However, chronic prenatal maternal stress may significantly contributes to pregnancy complications by disturbing hypothalamic-pituitary-adrenal (HPA) axis and the automatic nervous system (ANS), and results in unfavorable development of the fetus. Dysregulation of these two major stress response systems lead to the increased secretion of the glucocorticoids (GCs) which are known to be essential for normal development and the maturation of the central nervous system. As Hox genes are master key regulators of the embryonic morphogenesis and cell differentiation, we aimed to determine the effects of dexamethasone, a potent synthetic glucocorticoid, on gene expression in mesenchymal stem cell C3H10T1/2. Analysis of 39 Hox genes based on reverse transcription PCR (RT-PCR) method revealed that the expression patterns of Hox genes were overall upregulated by long dexametasone treatment. These results indicate that maternal stress may have a deleterious effect on early developing embryo through the stress hormone, glucocorticoid.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.2
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• pp.196-204
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• 2020

Objective: Chronic obstructive pulmonary disease(COPD) is characterized by persistent airflow limitations associated with chronic inflammatory response due to noxious particles or gases in the lung. Increasing oxidative stress associated with COPD. The aim of this study was to evaluate the influencing factors of biomarkers for oxidative stress in retired miners with COPD. Methods: The levels of total peroxide(TPx), total antioxidant capacity(TAC), and oxidative stress index(TPx/TAC ratio, OSI) in plasma as biomarkers for oxidative stress, serum C-reactive protein(CRP) as a biomarker for inflammation, and general characteristics were measured in 93 male subjects with COPD. COPD was defined as post bronchodilator FEV₁/FVC<0.7 by spirometry. Results: Mean levels of TPx(p=0.013), TAC(p=0.010), OSI(p=0.040), and CRP(p=0.024) were higher in current smokers. Levels of TPx(β=0.445, p<0.001), TAC(β=0.490, p<0.001), and OSI(β=0.351, p<0.001) were related to CRP levels, and CRP levels were related to %FEV₁ predicted(β=-0.295, p=0.003) and current smoking(β=0.214, p=0.032). Conclusions: These results suggest that oxidative stress was related to inflammation, and inflammation were related to decreasing %FEV₁ predicted and current smoking in retired miners with COPD.

• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.313-318
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• 2003

Environmental stresses, such as heat shock, alcohol and physiological salt have been shown to induce a group of protein called heat shock protein (HSPs) in various tissues. In this investigation, we studied that arsenic stress would alter contraction of isolated rat aorta and expression of heat shock protein 70 and investigated the relation between expression of HSP 70 and vascular contractility of isolated rat aorta. Rat aorta strips, mounted in organ baths were exposed to 0, 0.5, 1,2 and 4 mM arsonic for 60 min. and 1,3 and 8 hours later tested for contractile response and expression of heat shock protein 70. Contractility of rat aorta were determined by isometric transducer connected to computerized physiograph and expression of HSP 70 was characterized by western blotting, respectively. Potassium chloride (55 mM) significantly augmented vascular contractility of yat aorta by 39％ compared with the control at 8 hours but not one or three hours after treatment of 4 mM arsenic. Arsonic stress (4 mM) also increased the expression of HSP 70 in rat aorta at 8 hours but one or three hours compared with the control and HSP expressed in vascular smooth muscle cells and some expressed in endothelium cells. These results suggest that arsenic stress not only did alter the magnitude of the contractile response to high potassium chloride but also increased the expression of HSP 70 in the rat aorta.