• Smart Structures and Systems
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• v.32 no.5
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• pp.281-295
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• 2023

The purpose of this study is to demonstrate and verify the application of phase-control absolute-acceleration-feedback active tuned mass dampers (PCA-ATMD) to multiple-degree-of-freedom (MDOF) building structures. In addition, servo speed control technique has been developed as a replacement for force control in order to mitigate the negative effects caused by friction and inertia. The essence of the proposed PCA-ATMD is to achieve a 90° phase lag for a structure by implementing the desired control force so that the PCA-ATMD can receive the maximum power flow with which to effectively mitigate the structural vibration. An MDOF building structure with a PCA-ATMD and a real-time filter forming a complete system is modeled using a state-space representation and is presented in detail. The feedback measurement for the phase control algorithm of the MDOF structure is compact, with only the absolute acceleration of one structural floor and ATMD's velocity relative to the structure required. A discrete-time direct output-feedback optimization method is introduced to the PCA-ATMD to ensure that the control system is optimized and stable. Numerical simulation and shaking table experiments are conducted on a three-story steel shear building structure to verify the performance of the PCA-ATMD. The results indicate that the absolute acceleration of the structure is well suppressed whether considering peak or root-mean-square responses. The experiment also demonstrates that the control of the PCA-ATMD can be decentralized, so that it is convenient to apply and maintain to real high-rise building structures.

• Nutrition Research and Practice
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• v.17 no.5
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• pp.1019-1027
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• 2023

BACKGROUND/OBJECTIVES: Sustainability has become one of the top priorities in the foodservice industry. With an increase in consumer interest in sustainability and educational opportunities in higher education, it is important to know what sustainable practices are implemented in campus dining and how sustainable practices affect consumers' responses. This study aims to identify the key sustainable practices in the campus dining context, and investigate the relationship by applying the stimulus-organism-response framework to determine whether the key sustainable practices influence consumers' perception and behavioral intentions. SUBJECTS/METHODS: The self-administered online survey was distributed to college students in 8 dining halls at a large southeastern university in the United States from September 20-October 10, 2019. A total of 382 valid questionnaires were collected, and factor analysis and multiple regressions were utilized to test the research model. RESULTS: This study identified 4 dimensions of campus sustainability with a total of sustainable practices: sustainable food, waste management, energy/water conservation, and recycling/reuse. Three dimensions of sustainable campus practices (i.e., sustainable food, waste management, recycling/reuse) played a significant role in consumers forming a perceived value while energy/water conservation did not significantly influence the consumers' perceived value toward the campus dining. Waste management was identified as the most important practice to enhance consumers' perceived value (β = 0.330). Using sustainable food and recycling/reuse were ranked second and third, respectively (β = 0.262, β = 0.154). The findings confirmed the significant positive relationship between perceived value and revisit intentions. CONCLUSIONS: The findings support the inclusion of dining sustainability as a critical component in explaining college students' perceived value and revisit intention toward campus dining. Furthermore, this study provides practical implications for university administrators and foodservice operators to consider the key sustainable practices to meet the consumers' value and revisit intentions.

• Korean Chemical Engineering Research
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• v.62 no.2
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• pp.133-141
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• 2024

Atherosclerosis, a disease with high morbidity and mortality worldwide, is a chronic inflammatory disease that is a major cause of cardiovascular diseases such as stroke and myocardial infarction. Atherosclerosis is characterized by the accumulation of lipid deposits in the arteries, forming atheromas. This leads to the narrowing of the arteries and thrombosis. Recently, the need to develop bio-derived anti-atherosclerotic materials has been highlighted with concerns about the side effects of synthetic therapeutics. Accordingly, related research (such as the discovery of biomaterials for the improvement and treatment of atherosclerosis and the identification of mechanisms) has been actively conducted. Biomaterials including polysaccharides, polyphenols, and coenzyme Q10 have been reported to inhibit or delay symptoms by modulating factors involved in the development of atherosclerosis. For biomaterials with superior activity, in vivo anti-atherosclerotic activity has been confirmed. In this review, the pathogenesis of atherosclerosis was investigated, and the current status and application prospects of biomaterials with anti-atherosclerotic activity were proposed.

• Journal of the Korean Society of Food Culture
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• v.39 no.2
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• pp.119-126
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• 2024

This study was conducted to examine the microbiological quality indicators (total bacterial count and coliform count) and physicochemical quality indicators (pH, redness, volatile basic nitrogen [VBN] content) of meat according to various storage temperatures (-20~15℃) and packaging methods (wrap, vacuum). Based on these results, we proposed a safe consumption period. Redness, pH, and VBN content were not considered appropriate for setting the expiration date, as the redness and pH of the meat after spoilage were better than the standard values for both vacuum and wrap packaging (p<0.05). Additionally, the VBN content at 2 and 4℃ increased slightly (fresh level) until the initial time of spoilage (1.0×10⁶ colony-forming unit [CFU]/cm²) and then increased rapidly thereafter. Therefore, the results were not consistent with microbial spoilage. When the decay point was evaluated based on the presence of microorganisms, vacuum packaging extended the storage period approximately 2.5-fold when compared with wrap packaging, and the meat could be stored at 2 or 4℃ for 40 or 23 days, respectively. Therefore, to evaluate meat quality, microbial indicators should be considered first. The microbiological standards proposed in this study can be used for safety management during the distribution of meat. However, to ensure meat safety, additional investigations of appropriate indicators of freshness must be conducted.

• Anatomy and Cell Biology
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• v.56 no.2
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• pp.219-227
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• 2023

Adult neurogenesis has been reported in the hypothalamus, subventricular zone and subgranular zone in the hippocamp. Recent studies indicated that new cells in the hypothalamus are affected by diet. We previously showed beneficial effects of safflower seed oil (SSO), a rich source of linoleic acid (LA; 74%), on proliferation and differentiation of neural stem cells (NSCs) in vitro. In this study, the effect of SSO on hypothalamic neurogenesis was investigated in vivo, in comparison to synthetic LA. Adult mice were treated with SSO (400 mg/kg) and pure synthetic LA (300 mg/kg), at similar concentrations of LA, for 8 weeks and then hypothalamic NSCs were cultured and subsequently used for Neurosphere-forming assay. In addition, serum levels of brain-derived neurotrophic factor (BNDF) were measured using enzyme-linked immunosorbent assay. Administration of SSO for 8 weeks in adult mice promoted the proliferation of NSCs isolated from SSO-treated mice. Immunofluorescence staining of the hypothalamus showed that the frequency of astrocytes (glial fibrillary acidic protein⁺ cells) are not affected by LA or SSO. However, the frequency of immature (doublecortin⁺ cells) and mature (neuronal nuclei⁺ cells) neurons significantly increased in LA- and SSO-treated mice, compared to vehicle. Furthermore, both LA and SSO caused a significant increase in the serum levels of BDNF. Importantly, SSO acted more potently than LA in all experiments. The presence of other fatty acids in SSO, such as oleic acid and palmitic acid, suggests that they could be responsible for SSO positive effect on hypothalamic proliferation and neurogenesis, compared to synthetic LA at similar concentrations.

• Journal of the Korean institute of surface engineering
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• v.57 no.3
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• pp.214-220
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• 2024

In this study, three-dimensional (3D) networks structure using single-walled carbon nanotubes (SWCNTs) for Si-graphite composite electrode was developed and studied about effects on the electrochemical performances. To investigate the effect of SWCNTs on forming a conductive 3D network structure electrode, zero-dimensional (0D) carbon black and different SWCNTs composition electrode were compared. It was found that SWCNTs formed a conductive network between nano-Si and graphite particles over the entire area without aggregation. The formation of 3D network structure enabled to effective access for lithium ions leading to improve the c-rate performance, and provided cycle stability by alleviating the Si volume expansion from flexibility and buffer space. The results of this study are expected to be applicable to the electrode design for high-capacity lithium-ion batteries.

• IMMUNE NETWORK
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• v.20 no.3
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• pp.25.1-25.13
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• 2020

Acinetobacter baumannii is known for its multidrug antibiotic resistance. New approaches to treating drug-resistant bacterial infections are urgently required. Cathelicidin-related antimicrobial peptide (CRAMP) is a murine antimicrobial peptide that exerts diverse immune functions, including both direct bacterial cell killing and immunomodulatory effects. In this study, we sought to identify the role of CRAMP in the host immune response to multidrug-resistant Acinetobacter baumannii. Wild-type (WT) and CRAMP knockout mice were infected intranasally with the bacteria. CRAMP^-/- mice exhibited increased bacterial colony-forming units (CFUs) in bronchoalveolar lavage (BAL) fluid after A. baumannii infection compared to WT mice. The loss of CRAMP expression resulted in a significant decrease in the recruitment of immune cells, primarily neutrophils. The levels of IL-6 and CXCL1 were lower, whereas the levels of IL-10 were significantly higher in the BAL fluid of CRAMP^-/- mice compared to WT mice 1 day after infection. In an in vitro assay using thioglycollate-induced peritoneal neutrophils, the ability of bacterial phagocytosis and killing was impaired in CRAMP^-/- neutrophils compared to the WT cells. CRAMP was also essential for the production of cytokines and chemokines in response to A. baumannii in neutrophils. In addition, the A. baumannii-induced inhibitor of κB-α degradation and phosphorylation of p38 MAPK were impaired in CRAMP^-/- neutrophils, whereas ERK and JNK phosphorylation was upregulated. Our results indicate that CRAMP plays an important role in the host defense against pulmonary infection with A. baumannii by promoting the antibacterial activity of neutrophils and regulating the innate immune responses.

• Journal of Fashion Business
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• v.28 no.2
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• pp.1-14
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• 2024

Within the metaverse platform, users engage in communication with others through 'avatars' reflecting their own identities. Users experience various virtual fashion items through avatars, and the fashion industry anticipates avatars wearing virtual fashion items as an emerging business opportunity. Many fashion brands are currently releasing virtual fashion items specifically designed for avatars. In this study, we examined the impact of user identification with their avatar on their perception of the attributes of virtual fashion items (investment attractiveness, scarcity, playfulness, and aesthetics) and its influence on behavioral intentions. The research involved a survey of 250 females with prior knowledge of the metaverse. Structural equation modeling analysis was conducted to examine research hypotheses and validate the model. The results confirmed that as users within the metaverse perceive greater identification with their avatar, they also perceive the attributes of virtual fashion items more favorably. This finding affirms the self-reference effect, where users positively evaluate objects associated with themselves. Additionally, perceiving the attributes of virtual fashion items was found to be positively linked to purchase intentions for virtual products and actual interest in the brand. Lastly, a higher intention to purchase virtual fashion items was associated with forming a more favorable attitude toward the respective brand. Consequently, this study provides academic and practical implications for marketing strategies within the metaverse, emphasizing the active utilization of avatars and elements that facilitate user-avatar identification for effective engagement.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.221-226
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• 1985

This investigation was undertaken to clarify the effects of consecutive application of insecticide (Hexachlorocyclohexane: HCH, 10 ppm each year) and fungicide (Tetrachloroisophthalonitrile: TPN, 40 ppm each year) on changes of the composition of soil bacterial flora in the experimental plots treated with each pesticide for two years. For these purposes, the isolating of bacterial cells growing on albumin agar plate was carried out with non-treated, HCH-treated and TPN-treated soil. And these isolated strains were grouping in accordance with the first diagnostic table of Cowan & Steel based on the morphological and physiological characteristics of bacterial cells. The mortality rate of bacteria was 30% in control, 44% in HCH and 51% in TPN plot respectively, in the process of obtaining pure culture. This suggests that the application of HCH or TPN enriched the fastidious bacteria in soil. The proportion of Gram-negative strains to the total isolates was 37% in control, 37% in HCH and 75% in TPN plot respectively. This means that the application of TPN enriched Gram-negative strains in soil. And the application of TPN increased the number of Gram-negative, nonspore-forming strains, and meanwhile decreased the number of spore-forming strains. In the results, the application of HCH or TPN changed considerably the composition of soil bacterial flora. And the influences of HCH and TPH on changes of the composition of soil bacterial flora were not equal each to each.

• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.235-242
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• 2015

The objective of this study was to determine the effects of soluble potassium silicate by soil drenching application on watermelon growth, yield, and nutrient uptake. The potassium silicate rates were control (No potassium silicate), 1.63mM, 3.25mM, 6.50mM. The potassium silicate were treated 6 times (twice before fruit forming and 4 times after fruit forming per 7 day. Soil chemical properties, such as soil pH, EC, available phosphorus and silicate, exchangeable K, nitrate-N levels were increased after potassium silicate treatment, while the concentrations of soil organic matter, exchangeable Ca and Mg were similar to control. The growth characteristics of watermelon, such as stem diameter, fresh and dry weight of watermelon at harvest were thicker and heavier for increased potassium silicate treatment than the control, while number of node, and plant length were same for all treatments. With increased potassium silicate treatment, nutrient concentrations, such as P and K in the watermelon leaf at harvest were increased, N concentration in the leaf was decreased, and Ca and Mg concentrations in the leaf were same. Chlorophyll content was increased with increased potassium silicate application. The occurrence of powdery mildew was lower for the potassium silicate treatments than the control. Fresh watermelon weight for the potassium silicate treatments was 0.1 to 0.5kg per watermelon heavier than the control, sugar content was 0.5 to $0.6^{\circ}Brix$ higher than control, and merchantable watermelon was 2 to 4% increased compared to the control. These results suggest that potassium silicate application by soil drenching method in the greenhouse can improve watermelon nutrient uptake, merchantable watermelon and suppress the occurrence of powdery mildew.