• BMB Reports
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• v.42 no.12
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• pp.769-775
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• 2009

Periplasmic glucans (PGs) are general constituents in the periplasmic space of Proteobacteria. PGs from bacterial strains are found in larger amounts during growth on medium with low osmolarity and thus are often been specified as osmoregulated periplasmic glucans (OPGs). Furthermore, they appear to play crucial roles in pathogenesis and symbiosis. PGs have been classified into four families based on the structural features of their backbones, and they can be modified by a variety of non-sugar substituents. It has also recently been confirmed that novel PGs with various degrees of polymerization (DPs) and/or different substituents are produced under different growth conditions among Proteobacteria. In addition to their biological functions as regulators of low osmolarity, PGs have a variety of physico-chemical properties due to their inherent three-dimensional structures, hydrogen-bonding and complex-forming abilities. Thus, much attention has recently been focused on their physico-chemical applications. In this review, we provide an updated classification of PGs, as well as a description of the occurrences of novel PGs with substituents under various bacterial growth environments, the genes involved in PG biosynthesis and the various physico-chemical properties of PGs.

• BMB Reports
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• v.53 no.2
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• pp.65-73
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• 2020

Life expectancy has dramatically increased around the world over the last few decades, and staying healthier longer, without chronic disease, has become an important issue. Although understanding aging is a grand challenge, our understanding of the mechanisms underlying the degeneration of cell and tissue functions with age and its contribution to chronic disease has greatly advanced during the past decade. As our immune system alters with aging, abnormal activation of immune cells leads to imbalance of innate and adaptive immunity and develops a persistent and mild systemic inflammation, inflammaging. With their unique therapeutic properties, such as immunomodulation and tissue regeneration, mesenchymal stem cells (MSCs) have been considered to be a promising source for treating autoimmune disease or as anti-aging therapy. Although direct evidence of the role of MSCs in inflammaging has not been thoroughly studied, features reported in senescent MSCs or the aging process of MSCs are associated with inflammaging; MSC niche-driven skewing of hematopoiesis toward the myeloid lineage or oncogenesis, production of pro-inflammatory cytokines, and weakening their modulative property on macrophage polarization, which plays a central role on inflammaging development. This review explores the role of senescent MSCs as an important regulator for onset and progression of inflammaging and as an effective target for anti-aging strategies.

• Composites Research
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• v.24 no.2
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• pp.46-50
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• 2011

This paper describes the state of the art for the development of metallic armor materials which are mainly used as armor plates of the combat vehicles. Several important micro-structural features affecting ballistic properties of the metallic armor are discussed. Optimization of the strength and toughness balance of the metallic armor is necessary for the improvement of the ballistic performance resulting from maximizing the resistance to the penetration of the bullet and also to brittle failure of the plates. Understanding and control of the adiabatic shearing phenomenon developed remarkably during high strain rate deformation is needed to prevent brittle failure of the metallic armor materials.

• The Korean Journal of Cytopathology
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• v.3 no.2
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• pp.37-51
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• 1992

The fine needle aspiration (FNA) cytology findings in 19 cases of primary neoplasia of the pancreas are reported. The aspirates were obtained under ultrasound guidance in 16 cases and under direct vision intraoperatively in three cases. These cases represented 79% of 24 diagnoses in a series of 30 pancreatic FNAs. Of these 30 cases no cytologic diagnoses were made in six cases (20%) because of insufficient or inadequate samples The cytologic diagnoses were confirmed by histologic examination following resection or biopsy of the tumors. The diagnoses included 9 duct ceil adenocarcinomas, 1 mucinous adenocarcinoma, 2 mucinous cystadenocarcinomas, 1 acinar cell carcinoma, 1 papillary cystic tumor 3 islet ceil tumors, 1 neuroendocrine carcinoma and 1 leiomyosarcoma. The cytologic features of the neoplasia were detailed and the differential diagnosis was discussed. The important criteria for the cytodiagnosis of pancreatic tumors were reviewed. This review leads us to think that nonoperative (percutaneous) cytologic approaches to the diagnosis of pancreatic tumor are advantageous for the management of patients, and that correct cytologic diagnosis with pancreatic FNAs can easily be made, if adequate samples are obtained.

• The Korean Journal of Cytopathology
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• v.3 no.2
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• pp.52-59
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• 1992

A number of studies have shown the value of fine needle aspiration cytology for the diagnosis of breast lesions, but reports on the comparison of cytologic and histologic variations of breast cancers are few. We reviewed histologically proven 106 breast aspirates with an emphasis on the cytology of ductal carcinomas and of an area of uncertain atypia. Positive and negative predictive values of breast aspiration cytology were 100% On review of the cases originally diagnosed as atypia of uncertain nature (19 %), features more suggestive of malignancy or benignancy were recognizable in most underdiagnosed cases and a half of overdiagnosed cases, respectively. However, indistinguishable atypism also remained. Thirty seven cases out of 53 infiltrating duct carcinomas revealed malignant cytology, with variations in background, cellularity, morphology of cell groups, and extent of isolated tumor cells. When classifying the infiltrating duct carcinomas into scirrhous, solid-tubular, and papillotubular types, scirrhous type frequently appeared as irregularly shaped tight or loose cell clusters, and solid-tubular type as round-margined cell balls.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.5
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• pp.713-723
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• 2003

In this study, a state of art review of existing residual stress analysis techniques and representative solutions is presented in order to develope the residual stress analysis procedure for fitness-for-service (FFS) assessment of welded structure. Critical issues associated with existing residual stress solutions and their treatments in performing FFS are discussed. It should be recognized that detailed residual stress evolution is an extremely complicated phenomenon that typically involves material-specific ther-momechanical/metallurgical response, welding process physics, and structural interactions within a component being welded. As a result, computational procedures can vary significantly from highly complicated numerical techniques intended only to elucidate a small part of the process physics to cost-effective procedures that are deemed adequate for capturing some of the important features in a final residual stress distribution. Residual stress analysis procedure for FFS purposes belongs to the latter category. With this in mind, both residual stress analysis techniques and their adequacy for FFS are assessed based on both literature data and analyses performed in this investigation.

• Investigative Magnetic Resonance Imaging
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• v.21 no.2
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• pp.109-113
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• 2017

A 55-year-old male presented with dysesthesia of the right anteromedial thigh. A magnetic resonance image revealed a globular mass at the right extraforaminal area of the L3/4 level. Based on the diagnosis of neurogenic tumor, surgical excision was performed. The surgical impression and pathology confirmed extrusion of intervertebral disc. In a retrospective review of the magnetic resonance image, we noticed a fibrillary pattern directed from the intervertebral disc space to the lesion, and disrupted annulus fibrosus and indentation caused by the ring apophysis. We suggest aforementioned features, indicative of intervertebral disc lesions, to be checked when interpreting mass lesions around the intervertebral foramen.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.5
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• pp.489-500
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• 2012

This work surveys the trend and dissolution characteristics in headdress that appear in Jean Paul Gaultier's collection. Along with a related literature review, a total of 903 headdress pieces shown in collections 40 times (excluding the common caps and hats) were analyzed, covering from 2001S/S to 2010 F/W of Jean Paul Gaultier's Haute Couture and Pret-a-Porter. The headdress trend indicated in his collections was divided into such subgroup forms of folklore, usage of natural things, usage of artificial things, religion, retro, scarf, variations in headgear, mask and veil, atypical type and abstract. Such an expression tendency was so unique and mixed characteristic that it was hard to define its form and structure thanks to enlargement and exaggeration, extremity in ornaments, and use of foreign materials, which led to creative dynamics. Gaultier's headdress also reflected the following characteristics: first, expression of difference indicative of time deconstruction; second, uncertainty of meanings via deconstruction; third, text interactivity via deconstruction of gender and material adopted; fourth, decentralization through dissolution of the Orient and the Occident.

• Korean System Dynamics Review
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• v.16 no.2
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• pp.75-100
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• 2015

The purpose of this study is to analyze causation of Ecosystem service's trade-off(ES trade-off) and to establish baseline data for wise spatial planning and management. In order to understand why and how ES trade-off occurs, systems thinking and causal loops were employed. The causal loop of ecosystem service creation cycle includes profits quantification process, decision making process, spatial planning and management process, and ecosystem services creation process. The profits quantification process has a limitation that all ecosystem service categories were not included in profits quantification, because quantification method for cultural services is insufficient. These problems led to unequal discussion opportunity in decision making process. ES trade-off occurs through transition of ecosystem function in spatial scale and temporal scale. In spatial scale, land-use variation and resource-use variation contribute to change an ecosystem function for different ES category by spatial planning and management. In temporal scale, a change of an ecosystem function for different ES category is influenced by ecological succession, seasonal change and land cover variation, which are parameter from environmental features. This study presented that spatial planning and management should ecosystem service assessment in order to enhance balanced ecosystem services.

• Korean Journal of Head & Neck Oncology
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• v.28 no.2
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• pp.125-128
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• 2012

Salivary duct carcinoma(SDC) is a highly malignant tumor of the salivary gland. The tumor is clinically characterized by a rapid onset and progression, the neoplasm is often associated with pain and facial paralysis. The nodal recurrence rate is high, and distant metastasis is common. SDC resembles high-grade breast ductal carcinoma. Curative surgical resection and postoperative radiation were the mainstay of the treatment. If facial paralysis is present, a radical parotidectomy is mandatory. Regardless of the primary location of SDC, ipsilateral functional neck dissection is indicated, because regional lymphatic spread has to be expected in the majority of patients already at time of diagnosis. If there is minor gland involvement, a bilateral neck dissection should be performed, because lymphatic drainage may occur to the contralateral side. The survival of SDC patient is poor, with most dying within three years. We experienced a unique case of SDC in parotid deep lobe. We report the clinicopathologic features of this tumor with a review of literature.