• Journal of the Korean Arthroscopy Society
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• v.3 no.1
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• pp.40-43
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• 1999

Arthroscopic anterior cruciate ligament(ACL) reconstruction using four-strand hamstring tendon with looping around transfixing screw in femoral tunnel requires osteointegration between the grafted tendon and bone for stability of the knee. Authors have experienced a histologic finding of osteointegration between the grafted autogenous hamstring tendon and bone in femoral tunnel after arthroscopic ACL reconstruction. A patient received arthroscopic ACL reconstruction with autogenous four strand hamstring tendon for the ACL injury. Traumatic re-rupture of mid-substance of ACL graft was developed at thirteenth week after operation. During the procedures of arthroscopic revision at fifteenth week after initial ACL reconstruction, biopsy was performed at the site of interface between grafted tendon and bone in femoral tunnel. Integration between the grafted tendon and bone was evident by demonstrating the continuity of collagen fiber between bond and tendon. This histologic finding and the low incidence of early graft failure suggest that free tendon autograft attached to bone by looping around a transfixing screw in femoral tunnel undergoes adequate osteointegration between 12 and 15 weeks after surgery and authors thought that insertion of bone chip into the femoral tunnel would accelerate osteointegration procedure.

• The Korean Journal of Malacology
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• v.19 no.1
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• pp.9-17
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• 2003

The gonad index (GI), reproductive cycle with gonad developmental phases, first sexual maturity and the sex ratio of the jedo venus, Protothaca jedensis, on the coastal waters of Boryeong, Korea were investigated by histological study. Samples were collected from the subtidal zone of Boryeong, Korea from January to December, 1999. Monthly changes in the gonad index in femal and male clams gradually increased from February and reached the maximum in May, and then the values rapidly decreased from June and reached the minimum in November as seen in variations of the reproductive cycle. The spawning period of this species was once a year between May and July, there was a spawning peak between June and July when seawater temperature was over 20$^{\circ}C$. The reproductive cycle of this species in female and male clams can be classified into five successive stages: early active stage (December to March), late active stage (February to June), ripe stage (April to July), partially spawned stage (May to July) and spent/inactive stage (July to January). Percentages of first sexual maturity of female and male clams of 30.1-35.0 mm in shell length were 52.6% and 60.0%, respectively, and 100% for the clams over 45.1 mm in shell length. The sex ratio of individuals > 30.1 mm in shell length was 1:1 (X$^2$ = 0.40, p > 0.05).

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.3
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• pp.281-288
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• 2001

Lymphangiomas are relatively rare benign tumors of the lymphatic system, characterized by congenital lymphatic malformation such as anastomosis or obstuction of the lymphatic channels. There are most frequently diagnosed in children younger than 3years. In contrast to that of the hemangioma, the sex distribution of the lymphangioma is nearly evenly divided. The head and neck lymphangioma represents about $70{\sim}75%$ of all lymphangiomas, and they are difficult to manage. Spontaneous regression is rare, and rapid intermittent enlargement occurs secondary to infection or trauma. Enlargement may cause serious sequelae such as airway obstruction, feeding difficulties, and cosmetic problems. Treatments previously used for lymphangiomas include surgical excision and intralesional injection of sclerosants. Problems associated with surgical excision include the risk of cosmetically unacceptable scarring and the risk of damage to surrounding vital stricture and the high risk of incomplete excision. The sclerosants previously used have numerous other local and systemic side effects. This report describes a case that was successfully treated using OK-432 as a new sclerosant drug and secondary surgical excision for congential cavenous lymphangioma extensively enlarged to tongue, mouth floor and submandibular region.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.1
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• pp.19-31
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• 1982

The purpose of the research is to investigate the applicability of the filter activated sludge process for the treatment of toxic phenolic wastewaters. The experiment for the research was carried out by continuously feeding synthetic phenol wastewater for four periods, and the results show that a synthetic fiber filter is an adequate material for filter activated sludge process when taking consideration of durability, SS removal efficiency and wastewater permeability. The permeability of the filter sharply decreases when the temperature of the reactor is below $10{\sim}15^{\circ}C$ for a long period. In filter activated sludge process, even under high volumetric loading conditions, high phenol removal efficiencies can be attained due to the high microbial sludge concentration in the reactor and consequently low F/M ratio. In this research, the effluent phenol concentration were checked to be below $0.1mg/{\ell}$ at the influent phenol concentrations of $63{\sim}468mg/{\ell}$. During the research very low microbial yield coefficients, 0.035~0.160 kg SS/kg COD removed, were observed and the temperature coefficient for aerobic sludge digestion was measured to be 1.021.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.3
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• pp.33-44
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• 1987

To improve the ability of oxygen transfer in Biological Fluidised Bed(BFB) processes, air lift aeration system was introduced, experimental investigations were performed for the oxygen transfer in reactor, the fluidisation as to Biomass Volatile Solids variation and the relationship between substrate removal rate and oxygen utilization. The experiments for this purpose were executed for the synthetic wastewater by continuous type reactor at $20^{\circ}C$ using reticulated polypropylene sheets as media. The obtained results showed that the oxygen transfer by air lift aeration would be more effective than any other aeration systems used in BFB reactor. Also, it has observed that the critical biomass concentration in reactor took a range of 20 to 23g/l. Applying cages to BFB reactor, biomass would be maintained uniformly in the bed and the fluidisation characteristics of media could be improved. Varying F/M ratio from 0.36 to 0.73, BOD removals were 91% or more. Therefore, this process was suited to the treatment of which F/M ratios are variable and specific oxygen uptake rates ($K_r$) were 0.23 to 0.26g $O_2/g\;VSS{\cdot}day$ at range of 15 to 20g BVS/l.

• Composites Research
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• v.31 no.4
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• pp.139-144
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• 2018

Long Fiber-reinforced composites have advantages of excellent production efficiency and formability of complex shapes compared to conventional continuous fiber reinforced composite materials. However, if we need to make complicated composite shapes or to assemble parts made of different materials, a variety of joining methods are needed. In general, long fiber prepreg sheet (LFPS) contains mold release agent to facilitate demolding after thermoforming. Therefore, mechanical fastening is required in addition to the adhesive bonding to get proper joining strength. In this study, we proposed a stainless steel insert for co-cure bonding which cures LFPS and bonds the stainless steel insert through thermoforming process. The wing of the insert which is spread during the thermoforming process induces adhesion and mechanical wedging effect and serves as a hook to resist the pulling force. The burn-out method was used to confirm the unfolded state of the stainless steel insert wings inserted into the composite material. The static pull-out test was performed to quantitatively evaluate the joining strength. From these experimental results, the condition which guarantees the most appropriate joining strength was derived.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.559-568
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• 2020

Epidermal growth factor (EGF) is a hormone protein that affects cell growth and proliferation, and has various medical applications. In the present study, the gene of human EGF was codon-optimized with E. coli and the expression vector was constructed by cloning into pRSET. In order to obtain the recombinant human EGF in an active form rather than an inclusion body, chaperone co-expression was attempted along with codon optimization, for the first time. The expressed human EGF was isolated in the pure form by performing Ion Exchange Chromatography in two consecutive runs. ELISA analysis showed that the activity of purified EGF was greater than 99%, which is similar to commercially available EGF. Cell proliferation test confirmed that the recombinant human EGF has the ability to promote cell proliferation of human skin fibroblasts. The human EGF expression system of this study gives a significant amount of protein, and does not require the renaturation step and the additional chromatographic system to remove a fusion contaminant, thereby providing a very useful alternative to conventional expression systems for the preparation of recombinant human EGF.

• Applied Chemistry for Engineering
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• v.20 no.2
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• pp.145-153
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• 2009

The acute oral and genetic toxicity of ASCO EAQ80 was established in this study. ASCO EAQ80, a novel cationic surfactant produced by Aekyung Speciality Chemicals Co. LTD. is currently commercialized as a clear fabric softener. In acute oral toxicity study, the 50% lethal dose $(LD_{50})$ of ASCO EAQ80 was determined to be higher than 5000 mg/kg and this product could be classified as Category 5 or Unclassified by Globally Harmonized Classification System. Also, to establish the gene-toxicity of ASCO EAQ80, we performed bacterial reversion assay against Salmonella typhimurium TA98, TA100, TA1535, TA1537, Escherichia coli WP2uvrA, and in vitro chromosomal aberration assay against Chinese hamster lung cells in the presence and absence of S-9 metabolic activation system. From these experiments, ASCO EAQ80 revealed nonmutagenic potential in S. typhimurium TA98, TA100, TA1535, TA1537, and Escherichia coli WP2uvrA both in the absence and presence of metabolic activation system. No clastogenicity of ASCO EAQ80 was observed in chromosomal aberration assay in vitro.

• Applied Microscopy
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• v.41 no.4
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• pp.229-234
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• 2011

The occurrence of nuclear inclusions has been reported in various plant groups from primitive ferns to higher flowering plants. Their presence within a group seems to be randomly distributed without any phylogenetic relationships among species. According to the current survey, nuclear inclusions have been widely documented in more than several hundreds of species from various families of plants. The morphology and internal structures of nuclear inclusions are diverse and at least five types of inclusions develop within plant nuclei; amorphous, crystalline, fibrous, lamellar, and tubular form. Among these types, crystalline inclusions are the ones that are the most frequently reported. The inclusions are not bound by membranes and appear to be related to the nucleoli, either spatially by a close association or by an inverse relationship in size during development. The idea that nuclear inclusions are of a proteinaceous nature has been widely accepted. Further link to nucleolar activity as a protein storing site has also been suggested based on the association between the nucleolus and nuclear inclusions. Various investigations of nuclear inclusions have revealed more information about their structural features, but characterizing their precise function and subunit complexity employing molecular analysis and 3-D reconstruction remains to be elucidated. Tilting and tomography of serial sections with appropriate image processing can provide valuable information on their subunit(s). The present review summarizes discussion about different nuclear inclusions in plants from previous works, giving special attention to their fine, ultrastructural morphology, function, and origin.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.6
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• pp.501-508
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• 1987

Gonadal development, the annual reproductive cycle and the first sexual maturity of hen clam, Mactra chinensis were studied histologically. Sexuality of the species was dioecious. The gonads were irregularly arranged from the subregion of mid-intestinal 91an4 in visceral cavity to the reticular connective tissue of the foot. The ripe eggs were about $50-60\;{\mu}m$ in diameter, and they were surrounded by gelatinous membrane. The spawning period was from May to September when the water temperature ranged $18.5-27.0^{\circ}C$, with the peak in June and July. The annual reproductive cycle of Mactra chinensis could be classified into five successive stages; multiplicative, growing, mature, spent, and degenerative and resting. The monthly changes of the fatness coefficient closely correlated with the annual reproductive cycle. Percentages of the first sexual maturity of female and male clams were over $50\%$ among those individuals ranging from 3.5 to 3.9cm, and $100\%$ in those over 5.0cm in shell length.