• Journal of the Society of Naval Architects of Korea
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• v.60 no.5
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• pp.375-387
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• 2023

The subsea power cables are increasingly important for harvesting renewable energies as we develop offshore wind farms located at a long distance from shore. Particularly, the continuous flexural motion of inter-array dynamic power cable of floating offshore wind turbine causes tremendous fatigue damages on the cable. As the subsea power cable consists of the helical structures with various components unlike a mooring line and a steel pipe riser, the fatigue analysis of the cables should be performed using special procedures that consider stick/slip phenomenon. This phenomenon occurs between inner helically wound components when they are tensioned or compressed by environmental loads and the floater motions. In particular, Vortex-induced vibration (VIV) can be generated by currents and have significant impacts on the fatigue life of the cable. In this study, the procedure for VIV fatigue analysis of the dynamic power cable has been established. Additionally, the respective roles of programs employed and required inputs and outputs are explained in detail. Demonstrations of case studies are provided under severely sheared currents to investigate the influences on amplitude variations of dynamic power cables caused by the excitation of high mode numbers. Finally, sensitivity studies have been performed to compare dynamic cable design parameters, specifically, structural damping ratio, higher order harmonics, and lift coefficients tables. In the future, one of the fundamental assumptions to assess the VIV response will be examined in detail, namely a narrow-banded Gaussian process derived from the VIV amplitudes. Although this approach is consistent with current industry standards, the level of consistency and the potential errors between the Gaussian process and the fatigue damage generated from deterministic time-domain results are to be confirmed to verify VIV fatigue analysis procedure for slender marine structures.

• Animal Bioscience
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• v.37 no.1
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• pp.131-141
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• 2024

Objective: This experiment aimed to explore the protective action of dietary supplementation with isoquinoline alkaloids (IA) from Macleaya cordata on lipopolysaccharide (LPS)-induced liver injury in broilers. Methods: Total 216 healthy broilers were selected in a 21-d trial and assigned randomly to the following 3 treatments: control (CON) group, LPS group, and LPS+IA group. The CON and LPS groups were provided with a basal diet, whereas the LPS+IA group received the basal diet supplemented with 0.6 mg/kg Macleaya cordata IA. Broilers in LPS and LPS+IA groups were intraperitoneally injected with LPS (1 mg/kg body weight) at 17, 19, and 21 days of age, while those in CON group were injected with equivalent amount of saline solution. Results: Results showed LPS injection caused systemic and liver inflammation in broilers, inhibited immune function, and ultimately lead to liver injury. By contrast, supplementation of IA ameliorated LPS-induced adverse change in serum parameters, boosted immunity in LPS+IA group. Furthermore, IA suppressed the elevation of hepatic inflammatory cytokines and caspases levels induced by LPS, as well as the expressions of genes related to the toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor-kappa B (NF-κB) pathway. Conclusion: Dietary inclusion of 0.6 mg/kg Macleaya cordata IA could enhance immune function of body and inhibit liver damage via inactivating TLR4/MyD88/NF-κB signaling pathway in broilers.

• The Journal of Internal Korean Medicine
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• v.45 no.2
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• pp.190-198
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• 2024

Introduction: Central pontine myelinolysis (CPM) is a rare neurological disorder marked by symmetric nerve fiber damage, commonly following rapid hyponatremia correction, with no established treatment and a poor prognosis. The condition, often linked to alcoholism, malnutrition, and various diseases, lacks comprehensive studies on its impact on gait. This research aims to quantitatively analyze gait changes in CPM patients receiving both traditional Korean and conventional rehabilitation treatments, addressing a gap in current understanding of CPM management. Case presentation: A 56-year-old male diagnosed with CPM following an initial misdiagnosis underwent combined electoracupuncture and rehabilitative treatment at ○○ university Korean medical center, resulting in significant gait improvements. A treadmill gait analysis system was used to measure changes in key gait parameters at 2-week intervals, and the patient's progress was documented. Conclusions: The quantitative analysis revealed significant gait improvements. Foot rotation decreased from 8.9° to 6.4° (right) and from 11.1° to 7.2° (left); lateral symmetry improved from -7.8 to 0.8; step length increased from 21 cm to 44 cm (right) and from 19 cm to 44 cm (left); and velocity increased from 1.2 m/s to 2.7 m/s. These findings highlight decreased foot rotation and lateral symmetry, along with increased step length and velocity, suggesting a positive outcome of the treatment regimen. Notably, the patient experienced no adverse effects related to the treatments. Despite limitations, including the singe case focus and lack of prior gait-focused CPM research, this case report provides valuable insights into effective CPM management strategies, paving the way for future research in this domain.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.829-838
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• 2015

Garlic (Allium sativum L.), one of the oldest cultivated crops, is the most widely used Allium species belonging to the family Lilliaceae. In this study, growth characteristics, photosystem II activity, and antioxidative enzyme activity were investigated in five temperatures ($10-30^{\circ}C$) during early growth stage of garlic to determine the optimum temperature for cultivation and assess the effects of high temperature on early growth of garlic. Vegetative growth (e.g., shoot height, number of leaves) of garlic plants was greater in the temperature ranges of $15-25^{\circ}C$. However, dry weight (of shoot, bulb, and total plant) of garlic was significantly greater at $20^{\circ}C$, compared to either below or above $20^{\circ}C$. $F_v/F_o$ and $F_v/F_m$ values were highest at $15-20^{\circ}C$, and decreased above $25^{\circ}C$. The chlorophyll a fluorescence induction OKJIP transient was also considerably affected by high temperature; the fluorescence yields $F_i$ and $F_P$ decreased considerably above $25^{\circ}C$, with the increase of $F_k$ and $W_k$. Activities of catalase and superoxide dismutase in leaves and peroxidase in roots were high in $20-25^{\circ}C$, and decreased significantly in $30^{\circ}C$. These results indicate that a growth temperature of $30^{\circ}C$ inhibits early growth of garlic and that it is desirable to culture garlic plants near $20^{\circ}C$. Fluorescence parameters such a $F_v/F_o$, $F_v/F_m$, $F_k$, $ET_o/CS_m$, and $PI_{abs}$ were significantly correlated with dry weight of whole garlic plants (p < 0.01), indicating that these fluorescence parameters can be used for early assessment of high temperature effects even though the damage to the plant is not very severe.

• Korean Journal of Poultry Science
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• v.36 no.2
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• pp.165-175
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• 2009

Fatty liver-hemorrhagic syndrome (FLHS) is a common nutritional disease in commercial layers and breeders. The most important clinical sign of FLHS is a sudden drop in egg production and increased mortality which causes significant economic loss in the poultry industry. However, the current diagnostic method for FLHS is based on the gross findings at necropsy which is not helpful to reduce the economic loss because of lateness of diagnosis. Therefore, we need early diagnosis and diagnostic methods before chickens were affected by FLHS. In this study we tried to evaluate the effectiveness of clinical pathology including blood chemistry as an early diagnostic method for FLHS in commercial chickens. Profiles of blood biochemistry were compared between two flocks selected in the same commercial layer farm based on the presence of FLHS clinical sings. A flock with clinical signs of FLHS was designated as FLHS and other flock without clinical signs of FLHS as Non-FLHS. Several parameters of blood biochemistry were selected and compared between FLHS and Non-FLHS to evaluate the possibility of early diagnosis. Average concentrations of serum cholesterol, serum calcium, aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and creatine kinase (CK) were $139.4\;{\pm}\;87.2$ (mg/dL), $24.5\;{\pm}\;5.4$ (mg/dL), $153.6\;{\pm}\;23.1$ (IU/L), $1238.3\;{\pm}\;475.2$ (IU/L) and $1107.3\;{\pm}\;422.8$ (IU/L) in Non-FLHS flock, respectively, and $210.2\;{\pm}\;173.2$ (mg/dL), $25.2\;{\pm}\;4.1$ (mg/dL), $174.3\;{\pm}\;53.5$ (IU/L), $1694.9\;{\pm}\;691.3$ (IU/L) and $1104.9\;{\pm}\;472.9$ (IU/L) in FLHS flock, respectively. The activities of serum cholesterol, AST and LDH except CK, were significantly higher in FLHS than those in Non-FLHS flock (p<0.05). Some birds of FLHS flock showed 2~17 times greater than in Non-FLHS flock. For the definitive diagnosis of FLHS in the flocks tested for blood chemistry, we analyzed fat content and histological lesion score in the liver sampled from both FLHS and Non-FLHS flock. Average liver fat contents based on dry weight were $16.1\;{\pm}\;0.4$ (%) in Non-FLHS flock and were $21.6\;{\pm}\;16.0$ (%) in FLHS flock. These result confirmed that FLHS flock was definitely affected by FLHS. The above results suggest that selected parameters of blood biochemistry, particularly AST, could be useful to diagnose FLHS before significant liver damage occurred in commercial layers.

• Journal of Korean Society of Disaster and Security
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• v.12 no.2
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• pp.73-82
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• 2019

Recently, as the occurrence frequency of sudden floods due to climate change increased, the flood damage on riverside social infrastructures was extended so that there has been a threat of overflow. Therefore, a rapid prediction of potential flooding in riverside social infrastructure is necessary for administrators. However, most current flood forecasting models including hydraulic model have limitations which are the high accuracy of numerical results but longer simulation time. To alleviate such limitation, data driven models using artificial neural network have been widely used. However, there is a limitation that the existing models can not consider the time-series parameters. In this study the water surface elevation of the Hangang River bridge was predicted using the NARX model considering the time-series parameter. And the results of the ANN and RNN models are compared with the NARX model to determine the suitability of NARX model. Using the 10-year hydrological data from 2009 to 2018, 70% of the hydrological data were used for learning and 15% was used for testing and evaluation respectively. As a result of predicting the water surface elevation after 3 hours from the Hangang River bridge in 2018, the ANN, RNN and NARX models for RMSE were 0.20 m, 0.11 m, and 0.09 m, respectively, and 0.12 m, 0.06 m, and 0.05 m for MAE, and 1.56 m, 0.55 m and 0.10 m for peak errors respectively. By analyzing the error of the prediction results considering the time-series parameters, the NARX model is most suitable for predicting water surface elevation. This is because the NARX model can learn the trend of the time series data and also can derive the accurate prediction value even in the high water surface elevation prediction by using the hyperbolic tangent and Rectified Linear Unit function as an activation function. However, the NARX model has a limit to generate a vanishing gradient as the sequence length becomes longer. In the future, the accuracy of the water surface elevation prediction will be examined by using the LSTM model.

• Journal of Chest Surgery
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• v.39 no.12 s.269
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• pp.879-890
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• 2006

Background: The dysfunction of multiple organs is found to be caused by reactive oxygen species as a major modulator of microvascular injury after hemorrhagic shock. Hemorrhagic shock, one of many causes inducing acute lung injury, is associated with increase in alveolocapillary permeability and characterized by edema, neutrophil infiltration, and hemorrhage in the interstitial and alveolar space. Aggressive and rapid fluid resuscitation potentially might increased the risk of pulmonary dysfunction by the interstitial edema. Therefore, in order to improve the pulmonary dysfunction induced by hemorrhagic shock, the present study was attempted to investigate how to reduce the inflammatory responses and edema in lung. Material and Method: Male Sprague-Dawley rats, weight 300 to 350 gm were anesthetized with ketamine(7 mg/kg) intramuscular Hemorrhagic Shock(HS) was induced by withdrawal of 3 mL/100 g over 10 min. through right jugular vein. Mean arterial pressure was then maintained at $35{\sim}40$ mmHg by further blood withdrawal. At 60 min. after HS, the shed blood and Ringer's solution or 5% albumin was infused to restore mean carotid arterial pressure over 80 mmHg. Rats were divided into three groups according to rectal temperature level($37^{\circ}C$[normothermia] vs $33^{\circ}C$[mild hypothermia]) and resuscitation fluid(lactate Ringer's solution vs 5% albumin solution). Group I consisted of rats with the normothermia and lactate Ringer's solution infusion. Group II consisted of rats with the systemic hypothermia and lactate Ringer's solution infusion. Group III consisted of rats with the systemic hypothermia and 5% albumin solution infusion. Hemodynamic parameters(heart rate, mean carotid arterial pressure), metabolism, and pulmonary tissue damage were observed for 4 hours. Result: In all experimental groups including 6 rats in group I, totally 26 rats were alive in 3rd stage. However, bleeding volume of group I in first stage was $3.2{\pm}0.5$ mL/100 g less than those of group II($3.9{\pm}0.8$ mL/100 g) and group III($4.1{\pm}0.7$ mL/100 g). Fluid volume infused in 2nd stage was $28.6{\pm}6.0$ mL(group I), $20.6{\pm}4.0$ mL(group II) and $14.7{\pm}2.7$ mL(group III), retrospectively in which there was statistically a significance between all groups(p<0.05). Plasma potassium level was markedly elevated in comparison with other groups(II and III), whereas glucose level was obviously reduced in 2nd stage of group I. Level of interleukine-8 in group I was obviously higher than that of group II or III(p<0.05). They were $1.834{\pm}437$ pg/mL(group I), $1,006{\pm}532$ pg/mL(group II), and $764{\pm}302$ pg/mL(group III), retrospectively. In histologic score, the score of group III($1.6{\pm}0.6$) was significantly lower than that of group I($2.8{\pm}1.2$)(p<0.05). Conclusion: In pressure-controlled hemorrhagic shock model, it is suggested that hypothermia might inhibit the direct damage of ischemic tissue through reduction of basic metabolic rate in shock state compared to normothermia. It seems that hypothermia should be benefit to recovery pulmonary function by reducing replaced fluid volume, inhibiting anti-inflammatory agent(IL-8) and leukocyte infiltration in state of ischemia-reperfusion injury. However, if is considered that other changes in pulmonary damage and inflammatory responses might induce by not only kinds of fluid solutions but also hypothermia, and that the detailed evaluation should be study.

• Biomedical Science Letters
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• v.2 no.2
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• pp.133-151
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• 1996

After cardiac surgery, it has been recognized that various complications were associated with injured humoral and cellular immunity by cardiopulmonary bypass(CPB). Especially, in postoperative pulmonary dysfunction, transpulmonary leukostasis followed complement activation and inflammatory responses are major pathogen. Some studies have showed that pretreated-corticosteroids before CPB protected postoperative pulmonary dysfunction. Corticosteroids may inhibit complement and leukocyte activation. On based previous studies, present investigator determined changes of leukocyte counts and transpulmonary leukostasis during cardiac surgery and postoperative periods. For the evaluation of postoperative pulmonary function and edema, $PaO_2$ and chest X-ray were compared between pre-CPB and post-CPB. Fever and other parameters were also observed postoperatively. The aim of this study was to define for the prophylactic effects of corticosteroid(Solu-Medrol: 30mg/kg) on all the researched parameters. This study was prospectively designed with randomized-blind fashion for 50 patients undergoing cardiac surgery. According to the purpose of study, all patients were divided into placebo and steroid group. : Placebo group was 25 patients received normal saline(not corticosteroid), and steroid group was 25patients received corticosteroid(Solu-Medrol: 30mg/kg) before initiation of CPB. The results of study were summarized as follows. 1. Total peripheral leukocyte counts decreased significantly at 5 minutes of CPB in all patients(P<0.01), and began to increase progressively at later periods of CPB with neutrophilia. The significant rise remained at postoperative 7th day(P<0.05). 2. During partial CPB, transpulmonary leukostasis occurred in placebo group(P<0.001), whereas it was prevented in steroid group. 3. In both groups, peripheral lymphocyte counts were stable during CPB, but began to reduce at time of intensive care unit(ICU) and the lymphocytopenia remained until postoperative 3rd day. The lymphocyte counts recovered on postoperative 7th day. 4. In both groups, peripheral counts of monocyte were relatively stable in the early peroid of CPB, and increased gradually in the later periods of CPB. This significant monocytosis remained throughout postoperlative periods(P<0.05). 5. The mean value of postoperative $paO)_2$ was lower than that of pre-CPB in placebo group(P=0.01) but didn't significant in steroid group(P=0.90). In the incidence of pulmonary edema signs and fever, placebo group was higher than steroid group(P=0.001, p=0.01, respectively). However mechanical respiratory supporting and care periods at intensive care unit were not significant difference between two groups(P>.0.05).With the above results, the investigator concluded that leukocyte activation and pulmonary sequestration were caused by cardiac surgery with CPB and demonstrated that high dose corticosteroid will provide prophylactic effect for pulmonary leukostasis and higher neutrophilia. These effects may ameliorate postoperative pulmonary dysfunction and contribute to postoperative less morbidity. However, further study should be performed because postoperative lymphocytopenia continued for 3 days in both groups, which may suspected damage or suppression of cell-mediated immunity with used corticosteroid.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.220-227
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• 2016

The objective of this research was to investigate the influence of application rates of dolomitic lime in the acid substrate on the mitigation of high bicarbonate damage in 'Seolhyang' strawberry. For this purpose, an acid substrate was formulated by mixing of sphagnum peat moss and pine bark with the ratio of 5:5 (v/v). The pH, EC and CEC of the substrate analyzed before application of dolomite were 4.07, $0.46dS{\cdot}m^{-1}$, and $91.3cmol+/kg^{-1}$, respectively. To adjust the pH of substrate, various amounts of dolomitic lime [$CaMg(CO_3)_2$] such as 0 (control), 1, 2, 3, and $4g{\cdot}L^{-1}$ were added during substrate formulation. Then, seedlings with 3 leaf stage were transplanted as mother plants and those were fed with Hoagland solution containing $240mg{\cdot}L^{-1}$ of the $HCO_3{^-}$. The growth parameters of mother plants 140 days after transplanting, such as plant height, chlorophyll content, and fresh weight were the highest in the treatments of 2 and $3g{\cdot}L^{-1}$ of dolomitic lime. The physiological disorders in mother plants were not observed in the 1, 2 and $3g{\cdot}L^{-1}$ treatments, but the symptoms of Ca, K and B deficiencies were observed in the 0 and $4g{\cdot}L^{-1}$ treatments. During the propagation period, the number of daughter plants derived from each mother plant were 21.0, 29.5, 35.8, 27.3 and 16.0 in the treatments of 0, 1, 2, 3 and $4g{\cdot}L^{-1}$, respectively. The substrate pH during cultivation of mother plants were maintained at appropriate levels for the 1 and $2g{\cdot}L^{-1}$ treatments, whereas it was the highest in $4g{\cdot}L^{-1}$ treatment. The contents of macro- and micro-elements in the above ground tissue were the highest in $2g{\cdot}L^{-1}$ and the lowest in $4g{\cdot}L^{-1}$ lime treatments. Above results suggest that the bicarbonate injury originated from ground water can be mitigated by adjusting the amount of dolomitic lime incorporated into the acid substrate.

• Journal of Chest Surgery
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• v.37 no.9
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• pp.735-741
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• 2004

Blood cardioplegia is known as an established cardioplegic solution during open heart surgery. Recently, the Histidine-Tryptophan-Ketoglutarate (HTK) solution has been introduced as a cardioplegia in Korea. This study was designed to compare the myocardial protective effect between the cold blood cardioplegia (CBC) and HTK solution. Material and Method: Forty patients who underwent valve surgery or coronary artery bypass surgery were randomly divided into CBC group (n=20) and HTK group (n=20). The perioperative hemodynamic and clinical data were analyzed. The concentration of CK-MB, Troponin 1 and Lactate from coronary sinus and radial arterial blood were compared for the evaluation of the myocardial damage. The postoperative serial CK-MB levels were measured. Result: The characteristics of preoperative patients were similar in two groups. The hemodynamic parameters and postoperative clinical data were also similar between the two groups. There were no statistical significances between the CBC and HTK group in the difference of biochemical markers: Δ CK-MB (15.3$\pm$26.0 vs 19.3$\pm$14.3), ΔTro-1 (2.4$\pm$4.9 vs 2.0$\pm$2.20), ΔLac (1.6$\pm$1.0 vs 1.9$\pm$2.5). The serial CK-MB levels were not significantly different between the two groups. Conclusion: These results suggested that the myocardial protective effect of HTK solution was similar to cold blood cardioplegia during open heart surgery.