• Smart Structures and Systems
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• v.25 no.1
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• pp.65-80
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• 2020

In order to protect a structure over its full life cycle, a novel tuned mass damper (TMD), the so-called semi-active eddy current pendulum tuned mass damper (SAEC-PTMD), which can retune its frequency and damping ratio in real-time, is proposed in this study. The structural instantaneous frequency is identified through a Hilbert-Huang transformation (HHT), and the SAEC-PTMD pendulum is adjusted through an HHT-based control algorithm. The eddy current damping parameters are discussed, and the relationship between effective damping coefficients and air gaps is fitted through a polynomial function. The semi-active eddy current damping can be adjusted in real-time by adjusting the air gap based on the linear-quadratic-Gaussian (LQG)-based control algorithm. To verify the vibration control effect of the SAEC-PTMD, an idealized linear primary structure equipped with an SAEC-PTMD excited by harmonic excitations and near-fault pulse-like earthquake excitations is proposed as one of the two case studies. Under strong earthquakes, structures may go into the nonlinear state, while the Bouc-Wen model has a wild application in simulating the hysteretic characteristic. Therefore, in the other case study, a nonlinear primary structure based on the Bouc-Wen model is proposed. An optimal passive TMD is used for comparison and the detuning effect, which results from the cumulative damage to primary structures, is considered. The maximum and root-mean-square (RMS) values of structural acceleration and displacement time history response, structural acceleration, and displacement response spectra are used as evaluation indices. Power analyses for one earthquake excitation are presented as an example to further study the energy dissipation effect of an SAECPTMD. The results indicate that an SAEC-PTMD performs better than an optimized passive TMD, both before and after damage occurs to the primary structure.

• Journal of Veterinary Clinics
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• v.24 no.3
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• pp.337-341
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• 2007

This study determined the effect of postpartum intrauterine infusion of povidone-iodine solution on the subsequent reproductive performance in dairy cows. Six hundred and fifty-eight dairy cows that were around week 4 postpartum were randomly divided into two groups: (1) Cows in treated group received an intrauterine infusion of 100 to 150 ml 2% povidone-iodine solution (treated group, n=269), or (2) Cows that received no treatment were served as the controls (control group, n=389). The cows were bred at observed estrus more than 50 days after calving. Artificial insemination (AI) was done according to the a.m.-p.m. rule. The conception to AI was determined per rectum 60 days after AI by both ultrasonographical observation and manual palpation. The intervals from calving to first service and conception ($94.2{\pm}2.7$ and $144.1{\pm}4.1$ days vs. $88.0{\pm,}2.1$ and $143.5{\pm}4.6$ days, respectively), number of services per conception ($2.0{\pm}0.1$ vs. $2.1{\pm}0.1$), and cumulative pregnancy rates within 90 and 150 days postpartum (31.9 and 61.7% vs. 29.7 and 62.1%) did not differ between the control and treated groups (P>0.05), while conception rate at first service was lower (P<0.05) in the treated group (40.5%) than in the control group (49.4%). Additionally, we could not find any effect of intrauterine infusion of povidone-iodine solution according to cow parity or calving season on the reproductive performance. These results indicate that intrauterine infusion of povidone-iodine solution at week 4 postpartum does not affect the subsequent reproductive performance in dairy cows.

• Archives of Pharmacal Research
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• v.24 no.6
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• pp.572-577
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• 2001

The feasibility of skin penetration was studied for aspalatone (AM, acetylsalicylic acid maltol ester), a novel antithrombotic agent. In this studys hairless mouse dorsal skins were used as a model to select composition of vehicle and AM. Based on measurements of solubility and partition coefficient, the concentration of PC that showed the highest flux for AM across the hairless mouse skin was found to be 40%. The cumulative amount permeated at 48 h, however, appear inadequate, even when the PC concentration was employed. To identify a suitable absorption enhancer and its optimal concentration for AM, a number of absorption enhancers and a variety of concentration were screened for the increase in transdermal flux of AM. Amongst these, linoleic acid (LOA) at the concentration of 5% was found to have the largest enhancement factor (i.e., 132). However, a further increase in AM flux was not found in the fatty acid concentration greater than 5%, indicating the enhancement effect is in a bell-shaped currie. In a study of the effect of AM concentration on the permeation, there was no difference in the permeation rate between 0.5 and 1% for AM, below its saturated concentration. At the donor concentration of 2%, over the saturated condition, the flux of AM was markedly increased. A considerable degradation of AM was found during permeation studies, and the extent was correlated with protein concentrations in the epidermal and serosal extracts, and skin homogenates. In rat dorsal skins, the protein concentration decreased in the rank order of skin homogenate > serosal extract > epidermal extract. Estimated first order degradation rate constants were $6.15{\pm}0.14,{\;}0.57{\pm}0.02{\;}and{\;}0.011{\pm}{\;}0.004{\;}h^{-1}$ for skin homogenate, serosal extract and epidermal extract, respectively. Therefore, it appeared that AM was hydrolyzed to some extent into salicylmaltol by esterases in the dermal and subcutaneous tissues of skin. taken together, our data indicated that transdermal delivery of AM is feasible when the combination of PC and LOA is used as a vehicle. However, since AM is not metabolically stable, acceptable degradation inhibitors may be nervessary to fully realize the transdermal delivery of the drug.

• Environmental Engineering Research
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• v.24 no.1
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• pp.38-44
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• 2019

The Biochemical Methane Potential (BMP) of fresh leachate and domestic wastewaters codigestion was determined by laboratory Bach Tests at $35^{\circ}C$ over a period of 90 d using a wide range of leachates volumetric ratios from 0% to 100%. To simulate wastewaters plant treatment step, all the ratios were first air stripped for 48 h before anaerobic incubation. The kinetic of biogas production was assessed using modified Gompertz model and exponential equation. The results obtained showed that cumulative biogas production was insignificant in the case of wastewaters monodigestion while the codigestion significantly improves the BMP. Air stripping pretreatment had positive effect on both ammonium concentration and volatiles fatty acids with reduction up to 75% and 42%, respectively. According to the Modified Gompertz model, the optimal anaerobic co-digestion conditions both in terms of maximal biogas potential, start-up period and maximum daily biogas production rate, could be achieved within large leachate volumetric ratios from 25% to 75% with a maximum BMP value of 438.42 mL/g volatile solid at 50% leachate ratio. The positive effect of codigestion was attributed to a dilution effect of chemical oxygen demand and volatile fatty acid concentrations to optimal range that was between 11.7 to $32.3gO_2/L$ and 2.1 to 7.4 g/L, respectively. These results suggested that the treatment of fresh leachate by their dilution and co digestion at wastewaters treatment plants could be a promising alternative for both energetic and treatment purposes.

• Exercise Science
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• v.26 no.1
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• pp.61-68
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• 2017

PURPOSE: To examine the cumulative (7 days) effect of breaking up prolonged sitting on systemic endothelial function in sedentary men. METHODS: Thirty sedentary men ($33.93{\pm}5.72years$) participated in two randomized 7 days sitting trial (Sit group (control) vs. Breaks group). The protocol of Breaks group is as follows: 4-minute of moderate-intensity marching in place (walking) every 1 hour during business hour (total: 8 breaks/day). Assessment of brachial artery endothelial function using flow-mediated dilation (FMD) and arterial stiffness indices (augmentation index, arterial pressure and pulse wave velocity) were measured before and after 7 days treatment. RESULTS: Brachial artery FMD significantly increased after 7 days breaking up prolonged sitting treatment (Breaks groups, $9.65{\pm}2.61$ to $9.62{\pm}2.6%$) compared with 7 days prolonged sitting (Sit group, $8.37{\pm}3.41$ to $10.11{\pm}3.75%$) (interaction effect, p=.004). Arterial pressure (AP) significantly increased after treatment (Breaks group, $2.75{\pm}2.19$ to $2.38{\pm}1.63mmHg$, p=.002) in Sit group but there was no change (Sit group, $1.00{\pm}3.18$ to $2.50{\pm}9.23mmHg$) in Breaks groups (interaction effect, p=.008). CONCLUSIONS: These finding show that 7 days regular breaking up prolonged sitting improve in FMD, compared with prolonged sitting. Therefore, regular breaking up prolonged sitting may improve systemic endothelial function in sedentary men.

• Journal of Pharmacopuncture
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• v.25 no.2
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• pp.71-78
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• 2022

Objectives: Post-term pregnancy is a condition associated with increased maternal and fetal complications. Administration of castor oil causes cervical stimulation by increasing the production of prostaglandins. We examined the effects of castor oil on cervical ripening and labor induction through a systematic review and meta-analysis. Methods: The search process was performed to obtain relevant articles from databases including Pubmed, Cochrane library, Scopus, Science direct, SID, Iran Medex, and Google Scholar using the English keywords of cervical ripening, post-term, castor oil, labor induction, Bishop score, and pregnancy considering all possible combinations without time constraints and their Persian equivalents from national databases. Results: A total of eight related articles from the 19 primary studies were extracted and systematically reviewed. According to a cumulative chart, the difference in the post-intervention Bishop score was statistically significant (standard mean difference [SMD]: 1.64, 95% confidence interval [CI]: 1.67-2.11, p = 0.001), indicating an effect of castor oil on increasing the Bishop score. In addition, the difference in labor induction was statistically significant after the intervention (odds ratio: 11.67, 95% CI: 3.34-40.81, p = 0.001), indicating an effect of castor oil on increasing the odds ratio of labor induction (experience of vaginal delivery). Conclusion: This meta-analysis showed that oral administration of castor oil is effective for cervical ripening and labor induction. Midwives should closely monitor pregnant women with prolonged labor and collaborate with obstetricians to employ castor oil as a safe intervention to induce cervical ripening and labor to prevent undue caesarean surgery.

• Clinical and Experimental Pediatrics
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• v.65 no.5
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• pp.254-261
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• 2022

Background: The use of systemic steroids for 6+ weeks in children is associated with decreased bone mineral content (BMC) and density (BMD). However, the effects of a shorter duration of use on BMD are unknown. Purpose: To determine the effect of the use of systemic steroids for 2-6 weeks on BMD and BMC in pediatric patients. Methods: Twenty-five pediatric patients (21 with tuberculosis, 2 with systemic juvenile idiopathic arthritis, 1 with inflammatory bowel disease, 1 with autoimmune hemolytic anemia) who received systemic steroids for 2-6 weeks and 25 age- and sex-matched controls were enrolled. BMC, BMD, and z scores of the whole body (WB), lumbar spine (LS), nondominant distal radius (DR), and total body less the head (TBLH) were determined by dual-energy x-ray absorptiometry at baseline, the end of steroid therapy or 6 weeks (whichever was earlier; first follow-up), and at the end of 3 months from baseline (second follow-up) in patients and at baseline in controls. The values were adjusted for confounding variables. Continuous and categorical variables were compared using Student t test and the chi-square test or Fisher exact test, respectively. Pairwise comparisons employed Bonferroni correction. Results: Statistically significant decreases in BMC, BMD, and all z scores were observed. BMC declined by 5.37%, 2.08%, 1.82%, and 2.27%, and 11.42%, 3.75%, 3.34%, and 4.17% for WB, LS, DR, and TBLH, respectively, at the first and second follow-ups, respectively. Similarly, BMD declined by 2.01%, 2.31%, 2.18%, and 1.70% and 4.59%, 3.76%, 3.14%, and 3.50% for the WB, LS, DR, and TBLH, respectively, at the first and second follow-ups, respectively. A significant negative correlation was found among bone densitometric parameters, duration, and cumulative dose. Conclusion: The use of systemic steroids for 2-6 weeks in pediatric patients decreased the BMD and BMC of trabecular and cortical bones, an effect that persisted after discontinuation.

• Journal of Industrial Convergence
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• v.21 no.3
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• pp.37-48
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• 2023

Universities in Korea are presenting various extracurricular activities for survival and growth. Although the goals of extracurricular activities are diverse, one of the most important is to improve the academic achievement of college students. In this study, we looked at the relationship between the cumulative score of extracurricular activities by difficulty level and academic achievement. As a result, first, even if students' basic academic skills were controlled, extracurricular activities had a positive effect on student achievement. This suggests that universities should provide extracurricular activities that are more diverse and tailored to the needs of students. Second, the participation rate of female students in extracurricular activities is similar to that of male students, but the performance is very high. Third, Senior students show high levels of participation and performance. This means that it is necessary to actively increase the participation rate of female students and lower grade students. To this end, not only publicity and compensation, but also active interest and participation of instructors will be required.

• Korean Journal of Environmental Agriculture
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• v.42 no.4
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• pp.358-370
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• 2023

Composting has been proposed for the management of organic waste, and the resulting products can be used as soil amendments and fertilizer. However, the emissions of greenhouse gases (GHGs) such as CO₂, CH₄, and N₂O produced in composting are of considerable concern. Hence, various additives have been developed and adopted to control the emissions of GHGs. This review presents the different additives used during composting and summarizes the effects of additives on GHGs during composting. Thirty-four studies were reviewed, and their results showed that the additives can reduce cumulative CO₂, CH₄, and N₂O emission by 10.5%, 39.0%, and 28.6%, respectively, during composting. Especially, physical additives (e.g., biochar and zeolite) have a greater effect on mitigating N₂O emissions during composting than do chemical additives (e.g., phosphogypsum and dicyandiamide). In addition, superphosphate had a high CO₂ reduction effect, whereas biochar and dicyandiamide had a high N₂O reduction effect. This implies that the addition of superphosphate, biochar, and dicyandiamide during composting can contribute to mitigating GHG emissions. Further research is needed to find novel additives that can effectively reduce GHG emissions during composting.

• Journal of Korean Academy of Nursing
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• v.54 no.2
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• pp.119-138
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• 2024

Purpose: This study aimed to identify research trends related to emotional leadership among nurse managers by conducting a systematic literature review and meta-analysis. This study sought to derive insights that could contribute to improving emotional leadership in nursing practice. Methods: A systematic review and meta-analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) and Meta-Analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. Databases including PubMed, Cumulative Index to Nursing and Allied Health Literature, Scopus, Web of Science, Research Information Sharing Service, Koreanstudies Information Service System, Korean Medical Database, KoreaMed, ScienceON, and DBpia were searched to obtain papers published in English and Korean. Literature searches and screenings were conducted for the period December 1, 2023 to December 17, 2023. The effect size correlation (ESr) was calculated for each variable and the meta-analysis was performed using the statistical software SPSS 29.0, R 4.3.1. Results: Twenty-five (four personal, six job, and fifteen organizational) relevant variables were identified through the systematic review. The results of the meta-analysis showed that the total overall effect size was ESr = .33. Job satisfaction (ESr = .40) and leader-member exchange (ESr = .75) had the largest effect size among the job and organizational-related factors. Conclusion: Emotional leadership helps promote positive changes within organizations, improves organizational effectiveness, and increases member engagement and satisfaction. Therefore, it is considered an important strategic factor in improving organizational performance.