• Progress in Superconductivity and Cryogenics
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• v.20 no.4
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• pp.46-49
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• 2018

To improve in-field critical current densities ($J_c$) of $GdBa_2Cu_3O_{7-{\delta}}$ (GdBCO) coated conductors(CCs) fabricated by the reactive co-evaporation by deposition and reaction (RCE-DR) process, employing the nominal composition of Gd:Ba:Cu=1:1:2.5, we tried to refine the $Gd_2O_3$ particles trapped in the GdBCO superconducting matrix. For this purpose, we carefully selected the processing conditions on the stability phase diagram of GdBCO for this composition. By lowering the growth temperature of $Gd_2O_3$ in the liquid, we could refine the average particle size of $Gd_2O_3$ particles trapped in the GdBCO matrix and also achieve the zero-resistive transition temperatures ($T_{c,zero}$) of 92.3~94.2 K. Unfortunately, however, it was unsuccessful to achieve enhanced in-field $J_c$ values from these samples because of an air-contamination of the amorphous precursor film before its conversion into crystalline GdBCO film, suggesting that any exposure of the amorphous precursor film to air is fatal in obtaining high performance GdBCO CCs via the RCE-DR process.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.5
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• pp.447-452
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• 2019

Purpose: Few studies have reported non-acute long-term morbidity rates in children with intestinal malrotation. The aim of this study was to investigate the rate of constipation in children undergoing Ladd's procedure for isolated intestinal malrotation. Methods: This retrospective study included children aged <15 years who underwent Ladd's procedure for intestinal malrotation between 2001 and 2016. Demographics, presence of volvulus perioperatively, need for bowel resection, short term (<30 days) and long-term complications, including mortality were recorded. Constipation was defined as treatment with laxatives at 1-year follow-up. Results: Of the 43 children included in the study, 49% were boys. The median age at surgery was 28 days (0-5, 293 days). Volvulus occurred in 26 children (60.5%), and bowel resection was required in 4 children (9.3%). Short-term complications categorized as grades II-V according to the Clavien-Dindo classification occurred in 13 children (30.2%). Of these, 5 children (11.6%) required re-operation. Constipation was observed in 9 children (23.7%) at the 1-year follow-up. No difference was observed in the rate of perioperative volvulus between children with and without constipation (44% vs. 65%, p=0.45). Excluding re-operations performed within 30 days after surgery, 3 children (6%) underwent surgery for intestinal obstruction during the study period. Conclusion: Many children undergoing Ladd's procedure require bowel management even at long-term follow-up, probably secondary to constipation. It is important to thoroughly evaluate bowel function at the time of follow-up to verify or exclude constipation, and if treatment of constipation is unsuccessful, these children require evaluation for dysmotility disorders and/or intestinal neuronal dysplasia.

• Journal of Korean Physical Therapy Science
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• v.25 no.3
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• pp.43-52
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• 2018

Purpose: This study aims to draw students' attention to dementia and give students the right perception of dementia patients by comparing and analyzing students' awareness of dementia and educational needs of students in Honam area. In addition, the study will provide basic data that will help people develop education programs to prevent dementia. Methods: The study was conducted from May 10, 2018 to June 14, 2018, for 957 college students of physical therapy at 11 universities in Gwangju and Jeonnam. All participants understood the purpose of the study and agreed to participate in the study. Out of a total of 957 respondents, 950 people participated in the study, except for the seven who were unsuccessful in the survey. Results: Interest in dementia was found to be moderate, and many respondents answered that they had "information about dementia". Among them, broadcasting accounted for 41 percent of the total. Dementia awareness was categorized in four areas, symptom, disease, treatment, and nursing. In general, there is a low perception in all areas and improvement is needed. The need for dementia education was also different from what we thought. 649 students(68%) answered that they did not have dementia education. This is 349(36%) more than the 300 students(32%) who answered "Yes". Conclusion: The results show that college students lack awareness of dementia. In order to improve awareness of dementia, the government and community should be more interested in managing dementia, and active efforts to develop positive thinking and attitudes towards dementia.

• Journal of Yeungnam Medical Science
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• v.35 no.2
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• pp.179-186
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• 2018

Background: To evaluate the success rate of balloon dilation and the factors possibly influencing the outcomes of balloon dilation for the ureteric strictured portion of ureteroureterostomy (UUS) site in patients with post-gynecologic surgeries. Methods: A single institution data base was screened for the patients who received balloon dilation for a treatment of ureteral stricture diagnosed after gynecologic surgery. Overall 114 patients underwent primary intra-operative UUS due to ureteral injury during gynecologic surgery. Among them, 102 patients received balloon dilation, and their medical records were retrospectively reviewed. Success of balloon dilation was defined as the condition that requires no further clinical interventions after 6 months from balloon dilation. Results: The ureter injury rate of women treated with open radical abdominal hysterectomy was highest (32 cases, 31.4%). 60 patients (60.8%) showed successful outcomes regarding dilation. All patients underwent technically successful dilation with a full expansion of balloon during the procedure, but 40 patients (39.2%) were clinically unsuccessful as they showed a recurrence of ureteral stricture on the previous balloon dilation site after the first dilation procedure. Univariate logistic regression analyses showed that stricture length >2 cm was a significant predictor of successful dilation (odds ratio, 0.751; 95% confidence interval, 0.634-0.901; p-value, 0.030), but it failed to achieve independent predictor status in multivariate analysis. Conclusion: Balloon dilation can an effective alternative treatment option for strictured portion of the primary UUS in post-gynecologic surgery patients when its length is <2 cm.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3236-3246
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• 2021

Lessons learned from the Fukushima Daiichi nuclear power plant accident directed that multiple failures should be considered more seriously rather than single failure in the licensing bases and safety cases because attempts to take accident management measures could be unsuccessful under the high radiation environment aggravated by multiple failures, such as complete loss of electric power, uncontrollable loss of coolant inventory, failure of essential safety function recovery. In the case of the complete loss of electric power called station blackout (SBO), if there is no mitigation action for recovering safety functions, the reactor core would be overheated, and severe fuel damage could be anticipated due to the failure of the active heat sink. In such a transient condition at CANDU-6 plants, the seal failure of the primary heat transport (PHT) pumps can facilitate a consequent increase in the fuel sheath temperature and eventually lead to degradation of the fuel integrity. Therefore, it is necessary to specify the regulatory guidelines for multiple failures on a licensing basis so that licensees should prepare the accident management measures to prevent or mitigate accident conditions. In order to explore the efficiency of implementing accident management strategies for CANDU-6 plants, this study proposed a realistic accident analysis approach on the SBO transient with multiple-failure sequences such as seal failure of PHT pumps without operator's recovery actions. In this regard, a comparative study for two PHT pump seal failure modes with and without coolant seal leakage was conducted using a best-estimate code to precisely investigate the behaviors of thermal-hydraulic parameters during transient conditions. Moreover, a sensitivity analysis for different PHT pump seal leakage rates was also carried out to examine the effect of leakage rate on the system responses. This study is expected to provide the technical bases to the accident management strategy for unmitigated transient conditions with multiple failures.

• The Korean Journal of Pain
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• v.35 no.1
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• pp.43-58
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• 2022

Background: Current therapies are quite unsuccessful in the management of neuropathic pain. Therefore, considering the inhibitory characteristics of GABA mediators, the present systematic review and meta-analysis aimed to determine the efficacy of GABAergic neural precursor cells on neuropathic pain management. Methods: Search was conducted on Medline, Embase, Scopus, and Web of Science databases. A search strategy was designed based on the keywords related to GABAergic cells combined with neuropathic pain. The outcomes were allodynia and hyperalgesia. The results were reported as a pooled standardized mean difference (SMD) with a 95% confidence interval (95% CI). Results: Data of 13 studies were analyzed in the present meta-analysis. The results showed that administration of GABAergic cells improved allodynia (SMD = 1.79; 95% CI: 0.87, 271; P < 0.001) and hyperalgesia (SMD = 1.29; 95% CI: 0.26, 2.32; P = 0.019). Moreover, the analyses demonstrated that the efficacy of GABAergic cells in the management of allodynia and hyperalgesia is only observed in rats. Also, only genetically modified cells are effective in improving both of allodynia, and hyperalgesia. Conclusions: A moderate level of pre-clinical evidence showed that transplantation of genetically-modified GABAergic cells is effective in the management of neuropathic pain. However, it seems that the transplantation efficacy of these cells is only statistically significant in improving pain symptoms in rats. Hence, caution should be exercised regarding the generalizability and the translation of the findings from rats and mice studies to large animal studies and clinical trials.

• Journal of Aerospace System Engineering
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• v.16 no.6
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• pp.24-34
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• 2022

This paper investigates the capture of a 12U-sized CubeSat space object using a spider-web structure-based space net. The structural dynamics analysis program ABAQUS is used to simulate the shock-absorbing capability of the space net with a diagonal length of 2.828 m. The space object is modelled as a rigid body, and the space net is modelled using non-linear elastic beam elements. The simulations reveal that the spider-web structure-based space net outperforms the squared space net of the same structural weight in capturing the space object. The numerical simulations are conducted to examine the successful or unsuccessful captures of the space object in various cooperative and non-cooperative motions.

• Asia-Pacific Journal of Business
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• v.12 no.3
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• pp.1-36
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• 2021

Purpose - This empirical study, aims to identify the determinants of adoption and acceptance of mobile payment as to understand why it is successful in some countries in Sub-Saharan Africa but failing in others. A comparative study of a successful mobile payment service and a purported failed one was done as to have some insights to the factors affecting acceptance of the technology. Design/methodology/approach - The strength of three notable theories: theory of diffusion of innovation (DOI), the extended unified theory of user acceptance of information technology (UTAUT2) and self-efficacy theory were use. The self-efficacy of government support inclusion as, a moderating variable in the form of infrastructure, securing transaction and price value revealed the relevance of government in the success of mobile payment service. By means of a field survey of 705 subjects in two separate regions of Africa (East and West), the data was collected and use to test the research model. Findings - The study result shows the importance of the moderating factor of government support to the success of mobile payment of any nation. The result also shows the importance of the perception of relative advantage, compatibility, complexity, social influence as already revealed by other studies. Research implications or Originality - Mobile payment success in some part of Sub-Saharan Africa is well known but also suggested to fail in some Sub-Saharan African countries. Buttressing the need for understanding of the factors affecting mobile payment acceptance. This article empirically examined the factors influencing the success of mobile payment, and we implicated that if the implementation of mobile payment is to be successful for mobile commerce in any nation, adoption, acceptance and use by its citizen is imperative.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.239-243
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• 2023

Due to recent small unmanned aircraft threats by North Korea and unsuccessful reponses, severe concerns about future national security have been being increasingly surged. Especially it is notable and unaccpetable to see that North Korea's small drones flying over capical areas over 7 hours were not efficiently detected and identified even though South Korea already recognized the threats since early 2010s. Meanwhile a US military troop operating THAAD system on Seung-Joo, South Korea successfully shot down unidentified small drone on Jan 2023. The threats caused by small unmanned aircraft is worrisome not only to South Korea, but also to international nations. This paper surveyed US DoD Strategy for countering small aircraft systems and suggest how to improve our current anti-dron systems so that small unmanned aircraft threats will be dynamically diminished or neutralized as fast as we can.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• v.25 no.1
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• pp.13-18
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• 2023

Objective: Mechanical thrombectomy (MT) is an effective treatment for patients suffering from acute ischemic stroke secondary to large vessel occlusion. However, recanalization failure rates of interventions were about 20% in literature studies. We report our experience of unsuccessful MT with a focus on technical reasons. Methods: From December 2010 to June 2021, six hundred eight patients with acute ischemic stroke due to large artery occlusion received MT using a stent retriever with or without an aspiration catheter in our institution. We divided the reasons for failure into six categories. We analyzed the reasons for failure by dividing our experience time into 3 periods. Results: A total of 608 cases of thrombectomy for large vessel occlusion were identified in the study period. The successful recanalization rate was 90.4%. In most of the cases (20/57, 35%), the thrombus persisted despite several passes, and the second most common cause was termination of the procedure even after partial recanalization (10/57, 18%). Similar proportions of in-stent occlusion, distal embolization, and termination due to vessel rupture were observed. On analysis of three periods, the successful recanalization rate improved over time. Conclusions: MT fails due to various reasons, and intracranial artery stenosis is the main cause of MT failure. With the development of rescue techniques, the failure rate has gradually decreased. Further development of new devices and techniques could improve the recanalization rates.