• Geomechanics and Engineering
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• v.35 no.6
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• pp.603-615
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• 2023

Population growth and urbanization prompted engineers to propose more sophisticated and efficient transportation methods, such as underground transit systems. However, due to limited urban space, it is necessary to construct these tunnels in close proximity to existing infrastructure like high-rise buildings and bridges. Battered piles have been widely used for their higher stiffness and bearing capacity compared to vertical piles, making them effective in resisting lateral loads from winds, soil pressures, and impacts. Considerable prior research has been concerned with understanding the vertical pile response to tunnel excavation. However, the three-dimensional effects of tunnelling on adjacent battered piled foundations are still not investigated. This study investigates the response of a single battered pile to tunnelling at three critical depths along the pile: near the pile shaft (S), next to the pile (T), and below the pile toe (B). An advanced hypoplastic model capable of capturing small strain stiffness is used to simulate clay behaviour. The computed results reveal that settlement and load transfer mechanisms along the battered pile, resulting from tunnelling, depend significantly on the tunnel's location relative the length of the pile. The largest settlement of the battered pile occurs in the case of T. Conversely, the greatest pile head deflection is caused by tunnelling near the pile shaft. The battered pile experiences "dragload" due to negative skin friction mobilization resulting from tunnel excavation in the case of S. The battered pile is susceptible to induced bending moments when tunnelling occurs near the pile shaft S whereas the magnitude of induced bending moment is minimal in the case of B.

• Korean Journal of Radiology
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• v.22 no.9
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• pp.1537-1546
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• 2021

Objective: To assess the role of arterial spin-labeling (ASL) perfusion MRI in identifying cerebral perfusion changes after indirect revascularization in children with moyamoya disease. Materials and Methods: We included pre- and postoperative perfusion MRI data of 30 children with moyamoya disease (13 boys and 17 girls; mean age ± standard deviation, 6.3± 3.0 years) who underwent indirect revascularization between June 2016 and August 2017. Relative cerebral blood flow (rCBF) and qualitative perfusion scores for arterial transit time (ATT) effects were evaluated in the middle cerebral artery (MCA) territory on ASL perfusion MRI. The rCBF and relative time-to-peak (rTTP) values were also measured using dynamic susceptibility contrast (DSC) perfusion MRI. Each perfusion change on ASL and DSC perfusion MRI was analyzed using the paired t test. We analyzed the correlation between perfusion changes on ASL and DSC images using Spearman's correlation coefficient. Results: The ASL rCBF values improved at both the ganglionic and supraganglionic levels of the MCA territory after surgery (p = 0.040 and p = 0.003, respectively). The ATT perfusion scores also improved at both levels (p < 0.001 and p < 0.001, respectively). The rCBF and rTTP values on DSC MRI showed significant improvement at both levels of the MCA territory of the operated side (all p < 0.05). There was no significant correlation between the improvements in rCBF values on the two perfusion images (r = 0.195, p = 0.303); however, there was a correlation between the change in perfusion scores on ASL and rTTP on DSC MRI (r = 0.701, p < 0.001). Conclusion: Recognizing the effects of ATT on ASL perfusion MRI may help monitor cerebral perfusion changes and complement quantitative rCBF assessment using ASL perfusion MRI in patients with moyamoya disease after indirect revascularization.

• Journal of the Society of Naval Architects of Korea
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• v.61 no.2
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• pp.125-134
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• 2024

The Safe Operating Envelope (SOE) combined with Short-Take-Off and Vertical Landing (STOVL) performance is an essential consideration of a light aircraft carrier for design of hull shape with excellent seakeeping performance in terms of naval air operations as well as traditional naval ship missions such as Transit and Patrol (TAP), and Replenishment at Sea (RAS) and so on. A variety of procedures are systematically combined to determine SOE considering rather complicated missions associated with operation of aircraft onboard. The evaluation of take-off and landing safety missions onboard should consider wind effect on deck and severer seakeeping indices and standards compared with conventional naval ships. In order to support take-off and landing missions, various support activities of the crews are required. So, additional evaluation is needed for indicators such as MSI(Motion sickness Index) and MII(Motion Induced Interruptions), which are quantitative indicators of work ability that appear as a result of motion response. In this study, a standard procedure is developed including the seaworthiness performance indicators, standards, and evaluation procedures that should be considered during design of STOVL aircraft carrier. Analysis results are discussed in terns of air-wake on deck as well as seakeeping indices associated with design parameter changes in view of conceptual design of a light aircraft carrier.

• Korean Journal of Radiology
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• v.24 no.8
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• pp.784-794
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• 2023

Objective: To determine whether dynamic susceptibility contrast-enhanced (DSC) perfusion magnetic resonance imaging (MRI) can be used to evaluate posterior cerebral circulation in pediatric patients with moyamoya disease (MMD) who underwent anterior revascularization. Materials and Methods: This study retrospectively included 73 patients with MMD who underwent DSC perfusion MRI (age, 12.2 ± 6.1 years) between January 2016 and December 2020, owing to recent-onset clinical symptoms during the follow-up period after completion of anterior revascularization. DSC perfusion images were analyzed using a dedicated software package (NordicICE; Nordic NeuroLab) for the middle cerebral artery (MCA), posterior cerebral artery (PCA), and posterior border zone between the two regions (PCA-MCA). Patients were divided into two groups; the PCA stenosis group included 30 patients with newly confirmed PCA involvement, while the no PCA stenosis group included 43 patients without PCA involvement. The relationship between DSC perfusion parameters and PCA stenosis, as well as the performance of the parameters in discriminating between groups, were analyzed. Results: In the PCA stenosis group, the mean follow-up duration was 5.3 years after anterior revascularization, and visual disturbances were a common symptom. Normalized cerebral blood volume was increased, and both the normalized time-topeak (nTTP) and mean transit time values were significantly delayed in the PCA stenosis group compared with those in the no PCA stenosis group in the PCA and PCA-MCA border zones. TTP_PCA (odds ratio [OR] = 6.745; 95% confidence interval [CI] = 2.665-17.074; P < 0.001) and CBV_PCA-MCA (OR = 1.567; 95% CI = 1.021-2.406; P = 0.040) were independently associated with PCA stenosis. TTP_PCA showed the highest receiver operating characteristic curve area in discriminating for PCA stenosis (0.895; 95% CI = 0.803-0.986). Conclusion: nTTP can be used to effectively diagnose PCA stenosis. Therefore, DSC perfusion MRI may be a valuable tool for monitoring PCA stenosis in patients with MMD.

• Korean Journal of Radiology
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• v.20 no.5
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• pp.781-790
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• 2019

Objective: To assess the relationship between contrast-enhanced ultrasound (CEUS) parameters and perfusion CT (PCT) parameters of gastric cancers and their correlation with histologic features. Materials and Methods: This prospective study was approved by our Institutional Review Board. We included 43 patients with pathologically-proven gastric cancers undergoing CEUS using SonoVue^® (Bracco) and PCT on the same day. Correlation between the CEUS parameters (peak intensity [PI], area under the curve [AUC], rise time [RT] from 10% to 90% of PI, time to peak [TTP_US], and mean transit time [MTT_US]) and PCT parameters (blood flow, blood volume, TTP_CT, MTT_CT, and permeability surface product) of gastric cancers were analyzed using Spearman's rank correlation test. In cases of surgical resection, the CEUS and PCT parameters were compared according to histologic features using Mann-Whitney test. Results: CEUS studies were of diagnostic quality in 88.4% (38/43) of patients. Among the CEUS parameters of gastric cancers, RT and TTP_US showed significant positive correlations with TTP_CT (rho = 0.327 and 0.374, p = 0.045 and 0.021, respectively); PI and AUC were significantly higher in well-differentiated or moderately-differentiated tumors (n = 4) than poorly-differentiated tumors (n = 18) (p = 0.026 and 0.033, respectively), whereas MTT_CT showed significant differences according to histologic types (poorly cohesive carcinoma [PCC] vs. non-PCC), T-staging (≤ T2 vs. ≥ T3), N-staging (N0 vs. N-positive), and epidermal growth factor receptor expression (≤ faint vs. ≥ moderate staining) (p values < 0.05). Conclusion: In patients with gastric cancers, CEUS is technically feasible for the quantification of tumor perfusion and may provide correlative and complementary information to that of PCT, which may allow prediction of histologic features.

• Journal of Microbiology and Biotechnology
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• v.34 no.2
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• pp.367-378
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• 2024

In this study we sought to elucidate the therapeutic effects of fenchone on constipation-predominant irritable bowel syndrome (IBS-C) and the underlying mechanisms. An IBS-C model was established in rats by administration of ice water by gavage for 14 days. Fenchone increased the reduced body weight, number of fecal pellets, fecal moisture, and intestinal transit rate, and decreased the enhanced visceral hypersensitivity in the rat model of IBS-C. In addition, fenchone increased the serum content of excitatory neurotransmitters and decreased the serum content of inhibitory neurotransmitters in the IBS-C rat model. Meanwhile, western blot and immunofluorescence experiments indicated that fenchone increased the expressions of SCF and c-Kit. Furthermore, compared with the IBS-C model group, fenchone increased the relative abundance of Lactobacillus, Blautia, Allobaculum, Subdoligranulum, and Ruminococcaceae_UCG-008, and reduced the relative abundance of Bacteroides, Enterococcus, Alistipes, and Escherichia-Shigella on the genus level. Overall, fenchone ameliorates IBS-C via modulation of the SCF/c-Kit pathway and gut microbiota, and could therefore serve as a novel drug candidate against IBS-C.

• International Journal of Computer Science & Network Security
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• v.24 no.7
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• pp.87-100
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• 2024

Modern logistics significantly influences the globalization and internationalization processes. Logistics systems are becoming increasingly important in today's rapidly changing environment. On the other hand, the development of global economic integration, business globalization contributes to the creation and development of international logistics systems and global supply chains towards the international market. The aim of the article was to investigate the national logistics systems of developing countries in the context of their integration capabilities. The main methods used in this study are statistical analysis, index, graphical and analytical methods, methods for estimating structural dynamic shifts, comparisons. Commonly used methods of economic research, as well as statistical analysis and interstate comparisons, economic modelling (trend analysis to determine the forecast level of LPI for Ukraine), etc. were also involved. It is noted that the problem of development of logistics systems in developing countries was insufficiently covered in scientific research. The study suggests that the integration capabilities of national logistics systems are determined by the logistics performance of each country and the favourable logistics environment for integration transformations. This allowed analysing the state of the logistics systems of Poland, Bulgaria, India and Ukraine, and identifying the factors that determine it. The logistics environment of Poland, Bulgaria, India and Ukraine, as well as the factors of its formation are evaluated. The components of the logistic portrait of the country in the context of integration capabilities of the logistic system are offered. Trend analysis of LPI was carried out on the example of Ukraine, which showed positive trends in the logistics system and allowed drawing conclusions about increasing integration into international logistics channels based on its geopolitical location, improving the characteristics of the logistics environment, including customs regulation, and improving the efficiency of the national logistics system. Prospects for further research involve studies of the impact of pandemics, globalization, digitalization on logistics systems, including that of developing countries.

• Journal of Chest Surgery
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• v.36 no.9
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• pp.659-665
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• 2003

The aim of this study was to evaluate the early and midterm results of off-pump total arterial revascularization using the skeletonized right gastroepiploic artery (RGEA) as a third arterial conduit. Material and Method: We prospectively analyzed 103 patients who underwent off-pump total arterial revascularization using bilateral internal thoracic arteries (ITAS) and RGEA. The RGEA was used as in situ graft in 88 patients, composite graft in 10 patients, and free graft in 5 patients. Postoperative coronary angiographies were performed before discharge in 100 patients, and at postoperative one year in 88 patients. Result: The RGEA showed a significantly higher free flow (130$\pm$95 ml/min) than that of right ITA(113$\pm$57 ml/min) or left ITA (107$\pm$55 ml/min), which was measured before anastomosis (p < 0.05). The total number of distal anastomoses was 3.8$\pm$0.7. The number of distal anastomoses per bilateral ITAs was 2.8$\pm$0.7 and the number of distal anastomosis per RGEA was 1.0. There were two morialities including one operative mortality. The late mortality was not related to cardiac events. Early postoperative morbidities were atrial fibrillation in 15 patients, bleeding reoperation in 4 patients, mediastinitis in 1 patients, perioperative myocardial infarction in 2 patient, and transient ARF in 3 patients. Postoperative coronary angiographies showed the early patency rate of 98.6％ (272/276) for ITAs and 97.0％ (97/100) for RGEA, respectively (p=ns), and the one-year patency rate of 95.9％ (234/244) for ITAs and 88.6％ (78/88) for RGEA, respectively (p=0.07). Flow competition between the RGEA and NCA (native coronary artery) was seen in 5 of the 100 patients (5.0％) immediate postoperatively and 7 of the 88 patients (8.0％) 1 year after surgery. Since July, 2000, we measured transit time flow intraoperatively and could reduce flow competition significantly Conclusion: The skeletonized RGEA demonstrated excellent early and midterm patency rates and could be used as a third arterial graft following the bilateral ITAs.

• Food Science and Preservation
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• v.15 no.2
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• pp.280-287
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• 2008

We investigated the effect of dietary mulberry leaf powder (MP) on loperamide-induced constipation in rats. Male Sprague-Dawley rats were given MP in their diets at a concentration of 0% 5% and 10% for 33 days. Rats were divided into 4 groups: normal diet group (NOR), normal diet and loperamide treated group (MPL0), 5% MP and loperamide treated group (MPL5), and 10% MP and loperamide treated group (MPL10). Constipation was induced by subcutaneous injection of loperamide (1.5 mg/kg body weight/day) for the final 5 days of the experiment Supplemental MP had no effect on the food efficiency ratio, but it reduced body weight gain and food intake in a concentration dependent manner. Administration of loperamide decreased food intake. MP had a concentration-dependent effect on decreasing total cholesterol, LDL-cholesterol, and triglycerides and on increasing HDL-cholesterol. Loperamide had no significant effect on serum lipid profiles. Loperamide decreased the number and wet weight of fecal pellets and fecal water content MP increased the number and wet weight of fecal pellets and fecal water content in a dose-dependent manner. In addition, MP increased gut transit time and transit speed, and the guts of mts treated with MP plus loperamide were longer than those of mts treated with loperamide alone. These results indicate that MP is an effective treatment for constipation.

• Radiation Oncology Journal
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• v.8 no.1
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• pp.7-15
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• 1990

The ultimate objective of our experiment is to obtain the precise distribution of temperature in malignant tumors occurring in cerebral parenchyme of human beings when we will carry out interstitial hyperthermia in the near future. To achieve this purpose, first of all, it is necessary to make an attempt at performing interstitial hyperthermia in vivo under the similar condition of human beings. Therefore, we chose cats as materials much alike tissue characteristics of human beings. Moreover, it is also necessary to get the basic data from dynamic phantom in order to standardize and compare results obtained from interstitial hyperthermia carried out in cats. By having performed these experiments we got the following results. 1) On doing interstitial hyperthermia with 915 MHz microwave, the possible treated volume was 2 cm by 2 cm by 6 cm according to $50\%$ specific absorption rate (SAR). 2) The distribution of temperature within non-circulated static phantom was much the same as power density in air, but we observed that the temperature, within $5\~10$ minutes, rose to more higher than $55^{\circ}C$ not measured with Ga-As fiberoptic thermistor which was not impeded by microwave after performing interstitial hyperthermia. 3) Within dynamic phantom in which normal saline was circulating, temperature reached steady state which was maintained for more than 45 minutes through transit period in 5 minutes after starting interstitial hyperthermia. 4) When we interrupted circulation in the dynamic phantom, we observed that temperature rose to the same level as in the static phantom. 5) We could carry out interstitial hyperthermia safely when we used the generating power below 5 watts. Abrupt interruption of circulation caused a rapid increase in temperature. Times taking to rise to maximum $55^{\circ}C$ were 15.2 minutes (SE 0.4),9.7 minutes (SE 0.3), and 6.3 min-utes (SE 0.4) respectively with generating powers of 5,10, and 15 watts.