• Advances in concrete construction
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• v.7 no.3
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• pp.175-181
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• 2019

Low-calcium fly ash (LCFA) were used to prepare cement/LCFA specimens in this study. The basic physical properties including water demand, fluidity, setting time, soundness and drying shrinkage of cement/LCFA paste were investigated. The effects of curing time, immersion time and wet-dry cycles in 3% $Na_2SO_4$ solution on the compressive strength and the microstructures of specimens were also discussed. The results show that LCFA increases the water demand, setting time, soundness of cement paste samples. 50% and 60% LCFA replacement ratio decrease the drying shrinkage of hardened cement paste. The compressive strength of plain cement specimens decreases at the later immersion stage in 3% $Na_2SO_4$ solution. The addition of LCFA can decrease this strength reduction of cement specimens. For all specimens with LCFA, the compressive strength increases with increasing immersion time. During the wet-dry cycles, the compressive strength of plain cement specimens decreases with increasing wet-dry cycles. However, the pores in the specimens with 30% and 40% LCFA at early ages could be large enough for the crystal of sodium sulfate, which leads to the compressive strength increase with the increase of wet-dry cycles in 3% $Na_2SO_4$ solution. The microstructures of cement/LCFA specimens are in good agreement with the compressive strength.

• Archives of Plastic Surgery
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• v.49 no.3
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• pp.444-447
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• 2022

Reconstruction of soft tissue defects around the knee is challenging, and the most common solution is to use various locoregional flaps or, in some difficult cases, a free flap. The distally based anterolateral thigh (dALT) flap is a commonly used flap that relies on reverse blood flow from the descending branch of the lateral circumflex femoral artery (d-LCFA). Here, we present the case of an anteromedial knee reconstruction using a dALT flap after resection of a pleomorphic undifferentiated sarcoma. The tumor resection resulted in a 14 × 7 cm defect, and a dALT flap, measuring 20 × 8 cm was elevated. During the surgery, we found a robust oblique branch of the LCFA (o-LCFA) sending off two sizable perforators to the anterolateral thigh region, whereas the d-LCFA was relatively small with no usable perforators. Therefore, we harvested a dALT flap relying on reverse flow from the o-LCFA. The patient's postoperative course was uneventful, and the flap survived without complications. This report demonstrates that reverse flow from the o-LCFA may be an alternative to nourish a dALT flap in cases where the d-LCFA is hypoplastic or suitable perforators from the d-LCFA are unavailable.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.3
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• pp.395-400
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• 1993

Four sheep per treatment were fed either control or 3% calcium salts of long-chain fatty acids (Ca-LCFA) in a total mixed ration (TMR). Feed and free water intakes were not different, but digestibilities of crude protein and crude fiber were lower (p<0.05) and that of crude fat was higher (p<0.05) for sheep fed Ca-LCFA than for control sheep. Dry matter digestibility, ruminal pH and microbial protein yield were not different between treatments and ammonia-N concentration in the rumen was higher for sheep fed Ca-LCFA than for control sheep. A 60-day milk production trial was conducted with thirty lactation Holstein cows. Fifteen cows per treatment were fed TMR containing either control or 3% Ca-LCFA ad libitum. Feed intake was not different between treatments, but milk yield was significantly higher (p<0.05) for cows fed Ca-LCFA than for control cows. Milk fat percentage was slightly higher and milk protein was lower for cows fed Ca-LCFA than for control cows. Lactose and total solid contents in milk were not different between treatments.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.23-30
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• 2000

The effects of grass lipids and long chain fatty acids (LCFA; palmitic, stearic and oleic acids), at low concentrations (0.001~0.02%), on the growth and enzyme activity of two strains of anaerobic fungi, monocentric strain Piromyces rhizinflata B157 and polycentric strain Orpinomyces joyonii SG4, were investigated. The addition of grass lipids to the medium significantly (p<0.05) decreased filter paper (FP) cellulose digestion, cellulase activity and fungal growth compared to control treatment. However, LCFA did not have any significant inhibitory effects on fungal growth and enzyme activity, which, however, were significantly (p<0.05) stimulated by the addition of oleic acid as have been observed in rumen bacteria and protozoa. This is the first report to our knowledge on the effects of LCFA on the rumen anaerobic fungi. Continued work is needed to identify the mode of action of LCFA in different fungal strains and to verify whether these microorganisms have ability to hydrogenate unsaturated fatty acids to saturated fatty acids.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.8
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• pp.1110-1117
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• 2001

Responses of the rumen fungus, Neocallimastix frontalis RE1, to long chain fatty acid (LCFA) were evaluated by measuring gas production, filter paper (FP) cellulose digestion and polysaccharidase enzyme activities. LCFA (stearic acid, $C_{18:0}$; oleic acid, $C_{18:1}$; linoleic acid, $C_{18:2}$ and linolenic acid, $C_{18:3}$) were emulsitied by ultrasonication under anaerobic condition, and added to the medium. When N frontalis RE1 was grown in culture with stearic, oleic and linoleic acid, the cumulative gas production, gas pool size, FP cellulose digestion and enzymes activities significantly (p<0.05) increased at some incubation times(especially, exponential phases of fungal growth, 48~120 h of incubation) relative to that for control cultures. However, the addition of linolenic acid strongly inhibited all of the investigated parameters up to 120 h incubation, but not after 168 and 216 h of incubation. These results indicated that stearic, oleic and linoleic acids tended to have great stimulatory effects on fungal cellulolysis, whereas linolenic acid caused a significant (p<0.05) inhibitory effects on the cellulolysis by the rumen fungus. These results are the first report of the effect of LCFAs on the ruminal fungi. Further research is needed to identify the mode of action of LCFAs on fungal strains and to verify whether or not ruminal fungi have ability to hydrate unsaturated LCFAs to saturated FAs. There was high correlation between cumulative in vitro gas production and fungal growth (94.78%), FP cellulose degradation (96.34%), CMCase activity(90.86%) or xylanase activity (87.67%). Thus measuring of cumulative gas production could be a useful tool for evaluating fungal growth and/or enzyme production by ruminal fungi.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.3
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• pp.414-421
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• 2014

This study was conducted to determine the effects of saturated long-chain fatty acids (LCFA) on cell proliferation and triacylglycerol (TAG) content, as well as mRNA expression of ${\alpha}s1$-casein (CSN1S1) and genes associated with lipid and protein synthesis in bovine mammary epithelial cells (BMECs). Primary cells were isolated from the mammary glands of Holstein dairy cows, and were passaged twice. Then cells were cultured with different levels of palmitate or stearate (0, 200, 300, 400, 500, and 600 ${\mu}M$) for 48 h and fetal bovine serum in the culture solution was replaced with fatty acid-free BSA (1 g/L). The results showed that cell proliferation tended to be increased quadratically with increasing addition of stearate. Treatments with palmitate or stearate induced an increase in TAG contents at 0 to 600 ${\mu}M$ in a concentration-dependent manner, and the addition of 600 ${\mu}M$ was less effective in improving TAG accumulation. The expression of acetyl-coenzyme A carboxylase alpha, fatty acid synthase and fatty acid-binding protein 3 was inhibited when palmitate or stearate were added in culture medium, whereas cluster of differentiation 36 and CSN1S1 mRNA abundance was increased in a concentration-dependent manner. The mRNA expressions of peroxisome proliferator-activated receptor gamma, mammalian target of rapamycin and signal transducer and activator of transcription 5 with palmitate or stearate had no significant differences relative to the control. These results implied that certain concentrations of saturated LCFA could stimulate cell proliferation and the accumulation of TAG, whereas a reduction may occur with the addition of an overdose of saturated LCFA. Saturated LCFA could up-regulate CSN1S1 mRNA abundance, but further studies are necessary to elucidate the mechanism for regulating milk fat and protein synthesis.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05a
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• pp.323-326
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• 2001

• Journal of Korean Society of Environmental Engineers
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• v.31 no.12
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• pp.1075-1080
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• 2009

The partial lipid degradation with the saturation of double-bond at the acidogenesis stage is known to help subsequent methanogenesis during anaerobic digestion. Acidogenic reactions in an anaerobic sequencing batch reactor (ASBR) and a continuously stirred tank reactor (CSTR) were carried out to compare their performances. A mixture of two unsaturated (oleate and linoleate) and two saturated (palmitate and stearate) long-chain fatty acids (LCFAs) was used as a model substrate. Biomass retention in the ASBR contributed to the enhanced performance at hydraulic retention time (HRT) below 15 hr. Biomass retention in the ASBR contributed to the enhanced performance compared to CSTR even at shorter HRT. ASBR would be a proper reactor configuration for the acidogenesis of lipid-containing wastewater.

• Advances in concrete construction
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• v.6 no.2
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• pp.199-220
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• 2018

In this study, the effects of sulphuric acid on the mechanical performance and the durability of Engineered Cementitious Composites (ECC) specimens were investigated. The carbon fiber reinforced polymer (CFRP) and basalt fiber reinforced polymer (BFRP) fabrics were used to evaluate the performances of the confined and unconfined ECC specimens under static and cyclic loading in the acidic environment. In addition, the use of CFRP and BFRP fabrics as a rehabilitation technique was also studied for the specimens exposed to the sulphuric acid environment. The polyvinyl alcohol (PVA) fiber with a fraction of 2% was used in the research. Two different PVA-ECC concretes were produced using low lime fly ash (LCFA) and high lime fly ash (HCFA) with the fly ash-to-OPC ratio of 1.2. Unwrapped PVA-ECC specimens were also produced as a reference concrete and all concrete specimens were continuously immersed in 5% sulphuric acid solution ($H_2SO_4$). The mechanical performance and the durability of specimens were evaluated by means of the visual inspection, weight change, static and cyclic loading, and failure mode. In addition, microscopic changes of the PVA-ECC specimens due to sulphuric acid attack were also assessed using scanning electron microscopy (SEM) to understand the macroscale behavior of the specimens. Results indicated that PVA-ECC specimens produced with low lime fly ash (LCFA) showed superior performance than the specimens produced with high lime fly ash (HCFA) in the acidic environment. In addition, confinement of ECC specimens with BFRP and CFRP fabrics significantly improved compressive strength, ductility, and durability of the specimens. PVA-ECC specimens wrapped with carbon FRP fabric showed better mechanical performance and durability properties than the specimens wrapped with basalt FRP fabric. Both FRP materials can be used as a rehabilitation material in the acidic environment.

• Archives of Reconstructive Microsurgery
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• v.16 no.1
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• pp.39-47
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• 2007

With the advent of microsurgery, perforator free flap is nowadays considered the first choice for reconstruction of the extensive defect of the extremities because of their moderate thickness. Among them, anterior (anterolateral and anteromedial) thigh perforator free flaps provide the first choice for reconstruction of various soft tissue defects of the extremities with many advantage such as its large, uniform thickness, long vascular pedicle with proper vessel size and minimal donor site morbidity. But, it has still some criticism of unreliable perforators which makes us very careful in elevating the flap. Between March of 2006 and February of 2007, we treated 7 patients of soft tissue defects in the hand and lower extremities with anterior thigh perforator free flap at Hallym and DongGuk University Hospital. We performed 6 anterolateral thigh perforator free flaps based on the descending branch of lateral circumflex femoral artery (LCFA) and 1 anteromedial thigh perforator free flap based on the innominate branch of the LCFA. While approaching for the anterolateral thigh free flap, we happen to meet the cases which we should change into the anteromedial thigh free flap uneventfully on the operating field. In contrast to the original design of anterolateral thigh free flap, we had to harvest the anteromedial thigh perforator free flap in 1 case. All the anterior thigh perforator free flaps survived completely except 1 case of partial necrosis due to venous congestion. Donor sites were closed primarily and healed uneventfully within 2 weeks. Patients were satisfied with the functionally and aesthetically acceptable results. Although doppler sonography is strongly recommended preoperatively in planning the anterior thigh perforator free flaps, we should always remember the variation in vascular anatomy and be ready to change the flap choice from the anterolateral to anteromedial intraoperatively. we provide a review of the literature and present our series of anterior thigh perforator free flaps for reconstruction of the extremities.