• Smart Structures and Systems
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• v.7 no.3
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• pp.213-222
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• 2011

The native extracellular matrix (ECM) consists of an integrated fibrous protein network and proteoglycan-based ground (hydrogel) substance. We designed a novel electrospinning technique to engineer a three dimensional fiber-hydrogel composite that mimics the native ECM structure, is injectable, and has practical macroscale dimensions for clinically relevant tissue defects. In a model system of articular cartilage tissue engineering, the fiber-hydrogel composites enhanced the biological response of adult stem cells, with dynamic mechanical stimulation resulting in near native levels of extracellular matrix. This technology platform was expanded through structural and biochemical modification of the fibers including hydrophilic fibers containing chondroitin sulfate, a significant component of endogenous tissues, and hydrophobic fibers containing ECM microparticles.

• YAKHAK HOEJI
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• v.51 no.1
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• pp.7-12
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• 2007

Hepatic cirrhosis is an important feature of chronic liver disease. Liver cirrhosis is characterized by hyperaccumulation of fibrous tissue components and is commonly observed in latter or terminal states of chronic hepatic disease. The antifibrotic effects on liver cirrhosis by oriental herbs extraction material were examined in bile duct ligated rats. Oriental herbs extraction (0.99 mg/kg rat weight/day) was administrated to cirrohotic rats for 4 weeks. Liver collagen content of bile duct ligated rats was significantly increased. And liver histology showed collagen fiber deposition was increased as well as the normal architecture was lost with large zone of necrosis being observed. Herbs extraction administrated rats showed significantly decreased liver collagen content, accumulation of collagen fiber in histological analysis, and biochemical markers of hepatic diseases. Those results demonstrate the usefulness of herbs extraction materials as an antifibrotic agent for liver cirrhosis.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.3
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• pp.188-192
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• 2012

In this study, a carbon nanotube (CNT) flexible strain sensor was fabricated with CNT based epoxy and rubber composites for tactile sensing. The flexible strain sensor can be fabricated as a long fibrous sensor and it also may be able to measure large deformation and contact information on a structure. The long and flexible sensor can be considered to be a continuous sensor like a dendrite of a neuron in the human body and we named the sensor as a biomimetic artificial neuron. For the application of the neuron in biomimetic engineering, an ANMS (Artificial Neuron Matrix System) was developed by means of the array of the neurons with a signal processing system. Moreover, a strain positioning algorithm was also developed to find localized tactile information of the ANMS with Labview for the application of an artificial e-skin.

• Journal of the Mineralogical Society of Korea
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• v.20 no.4
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• pp.255-260
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• 2007

The loess on the Chinese loess plateau is not only the accumulation of Asian dust but also the source materials of Hwangsa. The eolian carbonates of the loess were dissolved and reprecipitated to form secondary pedogenic carbonates by the post-depositional weathering during the interglacial time. Mineralogical analysis shows that the secondary calcites are composed mostly of a nanosized fibrous calcite with rather constant width ($30{\sim}50nm$) and highly variable length. The nano calcite is the major authigenic mineral, which occurs as the fine-grained matrix of the loess and paleosol. The nano calcite was recently reported in the Hwangsa, where it was originated from the source regions of Chinese loess plateau.

• Imaging Science in Dentistry
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• v.49 no.2
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• pp.79-86
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• 2019

Purpose: This study reviewed the common conditions associated with displacement of inferior alveolar nerve canal. Materials and Methods: General search engines and specialized databases including Google Scholar, Pub Med, Pub Med Central, Science Direct, and Scopus were used to find relevant studies by using keywords such as "mandibular canal", "alveolar canal", "inferior alveolar nerve canal", "inferior dental canal", "inferior mandibular canal" and "displacement". Results: About 120 articles were found, of which approximately 70 were broadly relevant to the topic. We ultimately included 37 articles that were closely related to the topic of interest. When the data were compiled, the following 8 lesions were found to have a relationship with displacement of mandibular canal: radicular/residual cysts, dentigerous cyst, odontogenic keratocyst, aneurysmal bone cyst, ameloblastoma, central giant cell granuloma, fibrous dysplasis, and cementossifying fibroma. Conclusion: When clinicians encounter a lesion associated with displaced mandibular canal, they should first consider these entities in the differential diagnosis. This review would help dentists make more accurate diagnoses and develop better treatment plans according to patients' radiographs.

• Korean journal of applied entomology
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• v.32 no.1
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• pp.90-100
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• 1993

Ultrastructure of the larval hemocytes in Sericinus montela Grey was observed with the transmission and scanning electron microscope. The 5 cell types, according to Breh lin and Zachary(1986), identified in the hemocytes of the last instar S. montela larva were; prohemocyte, plasmatocyte, granular cell, spherule cell and oenocytoid. Prohemocytes could be easily charaterized by a relatively large nucleus nd poorly developed cytoplasmic organelles. Plasmatocytes were relatively large spindle-shaped or oval cells with fibrous bundles. The spindle-shaped plasmatocytes, especially, were characterized by a well developed, elongated nucleus. Granular cells had various granules, either morphologically or in electron density, and highly developed cytoplasmic organelles in the cytoplasm. They had numerous cytoplasmic processes. Spherule cells were characterized by cytoplasmic spherules containing fine materials, which are released into the hemolymph upon maturity of the cell. Oenocytoids consisted of electron dense materials and the organelles in cytoplasm were poorly developed.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.3
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• pp.238-247
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• 2005

The placement of different graft materials and/or the use of occlusive membranes to cover the extraction socket entrance are techniques aimed at reducing alveolar ridge resorption and enhancing bone formation. However, in spite of its clinical advantage, the use of graft materials in fresh extraction socket has been questioned because particles of the grafted material have been found in alveolar sockets with fibrous union. The purposes of this study were to evaluate whether alveolar ridge resorption following tooth extraction could be reduced and bone formation could be enhanced by the application of absorbable gelatin spongy or gelatin spongy soaked with platelet rich plasma(PRP) used as a space filler in clinical and radiographic aspects. Eighty patients who were scheduled for extraction of both third molars were participated and carried out by one experienced surgeon. Following extraction of teeth, one extracted socket were treated with gelatin spongy as an experimental group A and the other were treated with gelatin spongy and PRP as an experimental group B. The routine extracted socket were healed without any treatment as a control group. From the period of extraction to 12 weeks postoperatively, we examined the clinical course and radiographic evaluation on socket at regular interval. Both experimental groups showed faster wound healing process than control clinically. Vertical gingival height of the extraction socket were less changed statistically in both experimental groups than control. The horizontal width change of the extraction socket were not significant statistically in any group. Radiographic changes of the alveolar bone height were less changed in both experimental groups and bone density were showed higher than control. There were a little difference between experimental group A and B. In conclusion, absorbable gelatin sponge and with PRP were considered as having preservation effects of extraction socket and stimulation of bone formation process after extraction.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.11
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• pp.1767-1778
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• 2010

This study investigates applying $TiO_2$ (titanium dioxide) nanoparticles to polypropylene nonwoven fabrics via electrospinning for the development of UV-protective materials. To fabricate uniform nanocomposite fibers, three types of $TiO_2$ nanoparticles were applied: powder, colloid, and $TiO_2$ coated polymer pellets. $TiO_2$/polyurethane (PU) and $TiO_2$/poly(vinyl alcohol) (PVA) nanocomposite fibers were electrospun and the morphology was examined using a field-emission scanning electron microscope and a transmission electron microscope. Layered fabric systems with electrospun $TiO_2$ nanocomposite fiber webs were developed at various concentrations of $TiO_2$ in a range of the web area density. The effects of $TiO_2$ concentration and web area density on UV-protective properties were examined. When $TiO_2$ colloid was added into a PVA polymer solution, uniform nanocomposite fiber webs in which $TiO_2$ particles were evenly dispersed were produced. Water-soluble PVA nanofiber webs were given a heat treatment to stabilize the electrospun PVA fibrous structure against dissolution in water. $TiO_2$/PVA nanoeomposite fiber webs with 2wt% $TiO_2$ and 3.0g/$m^2$ web area density exhibited an ultraviolet protection factor of greater than 50, indicating excellent UV protection.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.1
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• pp.75-82
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• 2013

The traditional Hanji-making was confronted with lots of industrial disadvantages and economic problems, due to the original hand-made process. Recently, the studies on the automation of overall Hanji manufacturing process is carried out by applying the commercial chemical pulping method in order to expand industrial application or efficiency of non-wood fibrous materials. However, the application of commercial pulping methods to the bast tissues of paper mulberry leads to the chemical and mechanical deterioration of cellulosic fibers. In this study, the optimal cooking method using the bast parts of paper mulberry produced by an auto-scraping device was applied to minimize the damage of fiber strength for the paper yarn manufacture. The pre-steaming treatment and alkaline pulping systems were evaluated in removal efficiency of lignin and pectin materials within the bast tissue of paper mulberry. With the application of pre-steaming treatment and 2 stage pulping system using potassium carbonate and then sodium hydroxide, kappa values were decreased two times more in lignin removal than the single stage of pulping method. It was also identified from SEM images and ATR-FTIR spectra that the pectin components within cellular structure of bast tissue were easily removed and the debarked bast parts by a auto-scraping device were easily defiberized by 2-stage pulping sequence using potassium carbonate/sodium hydroxide pulping system.

• The Journal of the Korean bone and joint tumor society
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• v.5 no.1
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• pp.56-62
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• 1999

Purpose : This study was conducted to analyze the clinical materials and treatment results of 13 cases of subungual exostosis. Materials and Methods : Thirteen subungual exostoses of the foot treated from January 1991 to December 1997 were studied. We analyzed the clinical data and results of treatment to identify the clinical characteristics of this disease. We investigated the location, shape and relation of exostosis to phalanx with simple x-ray of the foot to identify the radiological characteristics. All the cases were sent to pathologic examination after resection to determine the pathological characteristics. Results : The results of physical examination on presentation were various. Most cases were located at the dorsomedial side of the distal phalanx and were involved in the toe nail. Eleven cases were located at great toes and one each at the 2nd and 3rd toe. Causes of exostosis were not clear, but 2 cases were related to trauma. For the type of exostosis, 7 cases were sessile and 6 were stalk type. On histologic examination, 9 cases showed a cartilaginous portion with overlying proliferating fibrous tissue and underlying bone formation. There was a gradual maturation of spindle cell proliferation from cartilage to cancellous bone. The cartilage was moderately cellular with some pleomorphism, but true anaplasia was not present. Conclusion : The clinical presentation and findings of simple x-rays were most helpful in diagnosing subungual exostosis. Complete excision of the mass achieved complete relief of symptoms and recovery without recurrence in all cases.