• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.30 no.1
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• pp.53-62
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• 2024

Molded pulp products has become more attractive than traditional materials such as expanded polystyrene foam (EPS) owing to low-priced recycled paper, environmental benefits such as biodegradability, and low production cost. In this study, various design factors regarding compression and cushioning characteristics of the molded pulp cushion with truncated pyramid-shaped structural units were analyzed using a test specimen with multiple structural units. The adopted structural factors were the geometric shape, wall thickness, and depth of the structural unit. The relative humidity was set at two levels. We derived the cushion curve model of the target molded pulp cushion using the stress-energy methodology. The coefficient of determination was approximately 0.8, which was lower than that for EPS (0.98). The cushioning performance of the molded pulp cushion was affected more by the structural factors of the structural unit than by the material characteristics. Repeated impacts, higher static stress, and drop height decreased the cushioning performance. Its compression behavior was investigated in four stages: elastic, first buckling, sub-buckling, and densification. It had greater rigidity during initial deformation stages; then, during plastic deformation, the rigidity was greatly reduced. The compression behavior was influenced by structural factors such as the geometric shape and depth of the structural unit and environmental conditions, rather than material properties. The biggest difference in the compression and cushioning characteristics of molded pulp cushion compared to EPS is that it is greatly affected by structural factors, and in addition, strength and resilience are expected to decrease due to humidity and repetitive loads, so future research is needed.

• Journal of the Korean Geotechnical Society
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• v.40 no.1
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• pp.55-63
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• 2024

In this study, a thermomechanical numerical model was developed to evaluate the stability of energy slabs. First, a wall-type energy slab was installed in a residential underground parking lot, and thermal performance tests were conducted. Based on the tests, a numerical thermohydraulics model of the energy slab was developed to accurately simulate the thermal behavior in thermal performance tests. Finally, utilizing the temperature data acquired using the developed model, a thermomechanical numerical model of the energy slab was established. The thermomechanical model was then used to simulate the thermal stresses induced by operating the energy slab. The results demonstrated a maximum thermal stress of 5,300 kPa, which highlights the need to utilize cement mortar with sufficient tensile strength to realize stable operation of the energy slab.

• Anatomy and Cell Biology
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• v.56 no.2
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• pp.200-204
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• 2023

Although in counterpart, the sphenopalatine artery (SPA), has been well described in the medical literature, the sphenopalatine vein (SPV) has received scant attention. Therefore, the present anatomical study was performed. Additionally, we discuss the variations, embryology, and clinical significance of the SPV. Adult cadaveric specimens underwent dissection of the SPV. In addition, some specimens were submitted for histological analysis of this structure. The SPV was found to drain from the sphenoidal sinus and nasal septum. Small tributaries traveled through the nasal septum with the posterior septal branches of the SPA and nasopalatine nerve. The SPA and SPV were found to travel through the sphenopalatine foramen and another tributary was found to perforate the medial plate of the pterygoid process and to connect to the pterygoid venous plexus which traveled lateral to the medial plate of the pterygoid process. The vein traveled through the posterior part of the lateral wall of the nasal cavity with the posterior lateral nasal branches of the SPA and the lateral superior posterior nasal branches of the maxillary nerve. To our knowledge, this is the first anatomical study on the SPV in humans. Data on the SPV provides an improved anatomical understanding of the vascular network of the nasal cavity. Developing a more complete picture of the nasal cavity and its venous supply might help surgeons and clinicians better manage clinical entities such as posterior epistaxis, cavernous sinus infections, and perform endoscopic surgery with fewer complications.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.27 no.4
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• pp.388-393
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• 2023

Backgrounds/Aims: Acute cholecystitis is a rare condition in pregnant women, potentially affecting the maternal and fetal prognosis. Our aim was to report the main clinical and paraclinical features of acute cholecystitis during pregnancy and therapeutic modalities. Methods: We conducted a case series analysis recording pregnant patients with acute cholecystitis admitted to our surgery department over a period of 11 years. We collected clinical data, paraclinical features, and management modalities related to cholecystitis. Results: There were 47 patients. Twenty-eight percent was in the first trimester of pregnancy, 40% in the second, and 32% in the third trimester. Abdominal pain was located in the right hypochondrium in 75% of cases. Fever was noted in 21% of cases. C-reactive protein was elevated in 39% of patients. Cholestasis markers were high in four patients. Abdominal ultrasound showed a distended gallbladder in 39 patients, with thickened wall in 34 patients, and gallbladder lithiasis in all cases. No patient had a dilated main bile duct. All patients received intravenous antibiotic therapy. Tocolysis was indicated in 32 patients. Laparoscopic cholecystectomy was performed in 32 cases (68%), and open cholecystectomy in 15 cases (32%). Postoperative course was uneventful in 42 patients, and complicated in 5 patients. Rate of complications was statistically higher after open cholecystectomy (p = 0.003). Morbidity rate was higher in the third trimester (p = 0.003). Conclusions: Delay in the diagnosis of acute cholecystitis during pregnancy can lead to serious complications. Management is based on antibiotic therapy and cholecystectomy. Laparoscopic cholecystectomy appears to be less morbid than open cholecystectomy.

• The Journal of the Convergence on Culture Technology
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• v.10 no.2
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• pp.91-97
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• 2024

Recently, with the rapid development of digital media technology, Realistic content that stimulates users' five senses is being used in various fields. This study focused on the case of the development of the Korea Industrial Complex Corporation's public relations center as the subject of the study to study the realistic content development process of public enterprises. First, the realistic content development process was divided into 10 stages and practical guidelines were presented to help develop realistic content in the future by presenting important development points and methods at each stage. Second, among the realistic content development processes, the importance of storytelling was analyzed at the scenario stage. Third, various methods of displaying content were analyzed. In the case of the Korea Industrial Complex Corporation's public relations center, it was proposed in three ways: story video, experience video, and media wall. It is suggested that the role of branding, promotion, and PR can be performed in one public relations center through an effective development process.

• Korean Journal of Radiology
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• v.1 no.4
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• pp.198-207
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• 2000

Uterine cervical carcinoma is one of the most common malignant tumors occurring in females. After primary treatment, patients are usually followed up with CT or MRI and the findings of these modalities may be the first sign of recurrent disease. Because earlier additional treatment by chemotherapy or radiation therapy may improve the prognosis, the early detection of recurrent cervical carcinoma is clinically important. In this article, we review the CT and MR imaging findings of recurrent uterine cervical carcinoma, and assign them to one of four groups: a) recurrence at the primary site, involving the intrapelvic organs, b) extension to the pelvic side-wall, c) metastases to pelvic and extrapelvic lymph nodes, or d) metastases to distant organs. A further contribution of CT and MR imaging is the detection of hydronephrosis due to ureteral obstruction. The cases in each group are illustrated and discussed, and since an awareness of the spectrum of imaging findings of recurrent cervical carcinoma is likely to lead to its early detection, radiologists should be familiar with the information presented.

• Molecules and Cells
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• v.46 no.12
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• pp.746-756
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• 2023

A recent study revealed that the loss of Deup1 expression does not affect either centriole amplification or multicilia formation. Therefore, the deuterosome per se is not a platform for amplification of centrioles. In this study, we examine whether gain-of-function of Deup1 affects the development of multiciliated ependymal cells. Our time-lapse study reveals that deuterosomes with an average diameter of 300 nm have two different fates during ependymal differentiation. In the first instance, deuterosomes are scattered and gradually disappear as cells become multiciliated. In the second instance, deuterosomes self-organize into a larger aggregate, called a deuterosome cluster (DC). Unlike scattered deuterosomes, DCs possess centriole components primarily within their large structure. A characteristic of DC-containing cells is that they tend to become primary ciliated rather than multiciliated. Our in utero electroporation study shows that DCs in ependymal tissue are mostly observed at early postnatal stages, but are scarce at late postnatal stages, suggesting the presence of DC antagonists within the differentiating cells. Importantly, from our bead flow assay, ectopic expression of Deup1 significantly impairs cerebrospinal fluid flow. Furthermore, we show that expression of mouse Deup1 in Xenopus embryos has an inhibitory effect on differentiation of multiciliated cells in the epidermis. Taken together, we conclude that the DC formation of Deup1 in multiciliated cells inhibits production of multiple centrioles.

• Archives of Plastic Surgery
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• v.50 no.6
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• pp.615-620
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• 2023

Massive localized lymphedema (MLL) is a rare disease caused by the obstruction of lymphatic vessels with specific clinical morphological and radiological characteristics. People with morbid obesity are mainly affected by MLL. Lymphedema is easily confused with soft tissue sarcoma and requires differential diagnosis, both the possibility of an MLL and also carcinoma manifestations in the soft tissues. The possible causes of massive lymphedema include trauma, surgery, and hypothyroidism. This report is the first case of MLL treated surgically in the Russian Federation. Detailed computed tomography (CT) characteristics and an electron microscope picture of MLL are discussed. A 50-year-old woman (body mass index of 43 kg/m²) with MLL arising from the anterior abdominal wall was admitted to the hospital for surgical treatment. Its mass was 22.16 kg. A morphological study of the resected mass confirmed the diagnosis of MLL. We review etiology, clinical presentation, diagnosis, and treatment of MLL. We also performed an electron-microscopic study that revealed interstitial Cajal-like cells telocytes not previously described in MLL cases. We did not find similar findings in the literature. It is possible that the conduction of an ultrastructural examination of MLL tissue samples will further contribute to the understanding of MLL pathogenesis.

• Steel and Composite Structures
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• v.51 no.4
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• pp.441-456
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• 2024

This paper aims to develop Machine Learning (ML) algorithms to predict the buckling resistance of cold-formed steel (CFS) channels with restrained flanges, widely used in typical CFS sheathed wall panels, and provide practical design tools for engineers. The effects of cross-sectional restraints were first evaluated on the elastic buckling behaviour of CFS channels subjected to pure axial compressive load or bending moment. Feedforward multi-layer Artificial Neural Networks (ANNs) were then trained on different datasets comprising CFS channels with various dimensions and properties, plate thicknesses, and restraining conditions on one or two flanges, while the elastic distortional buckling resistance of the elements were determined according to the Finite Strip Method (FSM). To develop less biased networks and ensure that every observation from the original dataset has the chance of appearing in the training and test set, a K-fold cross-validation technique was implemented. In addition, the hyperparameters of the ANNs were tuned using a grid search technique to provide ANNs with optimum performances. The results demonstrated that the trained ANNs were able to predict the elastic distortional buckling resistance of CFS flange-restrained elements with an average accuracy of 99% in terms of coefficient of determination. The developed models were then used to propose a simple ANN-based design formula for the prediction of the elastic distortional buckling stress of CFS flange-restrained elements. Finally, the proposed formula was further evaluated on a separate set of unseen data to ensure its accuracy for practical applications.

• Journal of the Korean Society of Radiology
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• v.84 no.1
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• pp.34-50
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• 2023

In 2019, the American College of Radiology announced Lung CT Screening Reporting & Data System (Lung-RADS) 1.1 to reduce lung cancer false positivity compared to that of Lung-RADS 1.0 for effective national lung cancer screening, and in December 2022, announced the new Lung-RADS 1.1, Lung-RADS^Ⓡ 2022 improvement. The Lung-RADS^Ⓡ 2022 measures the nodule size to the first decimal place compared to that of the Lung-RADS 1.0, to category 2 until the juxtapleural nodule size is < 10 mm, increases the size criterion of the ground glass nodule to 30 mm in category 2, and changes categories 4B and 4X to extremely suspicious. The category was divided according to the airway nodules location and shape or wall thickness of atypical pulmonary cysts. Herein, to help radiologists understand the Lung-RADS^Ⓡ 2022, this review will describe its advantages, disadvantages, and future improvements.