• Journal of Korean Neurosurgical Society
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• v.64 no.4
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• pp.575-584
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• 2021

Objective : Cervical expansive laminoplasty is an effective surgical method to address multilevel cervical spinal stenosis. During surgery, the spinous processes of C2 and C7 are usually preserved to keep the insertion points of the cervical musculature and nuchal ligament intact. In this regard, dome-like laminectomy (undercutting of C7 lamina) instead of laminoplasty is performed on C7 in selected cases. However, resection of the lamina can weaken the C7 lamina, and stress fractures may occur, but this complication has not been characterized in the literature. The objective of the present study was to investigate the incidence and risk factors for C7 laminar fracture after C7 dome-like laminectomy and its impact on clinical and radiological outcomes. Methods : Patients who underwent cervical open-door laminoplasty combined with C7 dome-like laminectomy (n=123) were classified according to the presence of C7 laminar fracture. Clinical parameters (neck/arm pain score and neck disability index) and radiologic parameters (C2-7 angle, C2-7 sagittal vertical axis, and C7-T1 angle) were compared between the groups preoperatively and at postoperatively at 3, 6, 12, and 24 months. Risk factors for complications were evaluated, and a formula estimating C7 fracture risk was suggested. Results : C7 lamina fracture occurred in 32/123 (26%) patients and occurred at the bilateral isthmus in 29 patients and at the spinolaminar junction in three patients. All fractures appeared on X-ray within 3 months postoperatively, but patients did not present any neurological deterioration. The fracture spontaneously healed in 27/32 (84%) patients at 1 year and in 29/32 (91%) at 2 years. During follow-up, clinical outcomes were not significantly different between the groups. However, patients with C7 fractures showed a more lordotic C2-7 angle and kyphotic C7-T1 angle than patients without C7 fractures. C7 fracture was significantly associated with the extent of bone removal. By incorporating significant factors, the probability of C7 laminar fracture could be assessed with the formula 'Risk score = 1.08 × depth (%) + 1.03 × length (%, of the posterior height of C7 vertebral body)', and a cut-off value of 167.9% demonstrated a sensitivity of 90.3% and a specificity of 65.1% (area under the curve, 0.81). Conclusion : C7 laminar fracture can occur after C7 dome-like laminectomy when a substantial amount of lamina is resected. Although C7 fractures may not cause deleterious clinical outcomes, they can lead to an unharmonized cervical curvature. The chance of C7 fracture should be discussed in the shared decision-making process.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.199-204
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• 1977

The patterns of fatty acid composition of lipid extracted from eight species of edible marine benthic algae; i. e. two species of green, five of brown and one of red algae, were investigated quantitatively by using gas liquid chromatography. The total lipid contents in average of the algae were $1.51\%$ in the green algae, $2.81\%$ in brown algae and $1.02\%$ in red algae respectively. Upon analyzing fatty acid composition, green algae contained the highest proportion of $C_{16:0}$ acid and comparatively higher content of $C_{18:1},\;C_{18:2}\;and\;C_{18:3}$ acids than the other algae. In brown angae, $C_{16:0}$ acid content was highest, but not more than that of green algae, and $C_{14:0},\;C_{18:1}$ acids were higher than other $C_{16:1},\;C_{18:2}\;and\;C_{18:3}$ acids while the content of $C_{18:0}$ acid was very low. Red algae showed low content of $C_{14:0},\;C_{18:1},\;C_{18:2}\;and\;C_{18:3}$ acids, but the content of $C_{16:0}$ acid was high as a major component. In regard to the composing patterns of carbon number of fatty acid of algae; i. e. $C_{14},\;C_{15},\;C_{16},\;C_{18}\;and\;C_{22}$ and $C_{22}$ acids, the green algae contained $C_{16}$ and $C_{18}$ acids, the brown algae $C_{16},\;C_{18},\;and\;C_{22}$ and $C_{22}$ acids, and the red algae $C_{15},\;C_{16}$, and $C_{18}$ acids as the major component.

• The Journal of Natural Sciences
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• v.15 no.1
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• pp.79-88
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• 2005

There are five isoforms of thiol peroxidase in yeast. Each isoform was named after its subcellular localization such as cytoplasmic TPx I, cTPx II, cTPx III, mitochondrial TPx (mTPx), and nuclear TPx (nTPx). Recently, we reported that unlike other TPx null mutants, cTPx IInull mutant showed a slow-growth phenotype. This observation suggests that cTPx II might be involved in yeast cell growth. In this study, for a first step toward to investigate the physiological function of cTPx II in yeast, we have identified a novel interaction between cTPx II and various proteins by using the yeast two-hybrid system.

• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.189-195
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• 2023

As a PEMFC (Polymer Exchange Membrane Fuel Cell) cathode catalyst, Pt-Co/C has recently been widely used because of its improved durability. In a fuel cell, electrodes and electrolytes have a close influence on each other in terms of performance and durability. The effect on the electrochemical durability of the electrolyte membrane when Pt-Co/C was replaced in the Pt/C electrode catalyst was studied. The durability of Pt-Co/C MEA (Membrane Electrode Assembly) was higher than that of Pt/C MEA in the electrochemical accelerated degradation process of PEMFC membrane. As a result of analyzing the FER (Fluorine Emission Rate) and hydrogen permeability, it was shown that the degradation rate of the membrane of Pt-Co/C MEA was lower than that of Pt/C MEA. In the OCV (Open Circuit Voltage) holding process, the rate of decrease of the active area of the Pt-Co/C electrode was lower than that of the Pt/C electrode, and the amount of Pt deposited on the membrane was smaller in Pt-Co/C MEA than in Pt/C MEA. Pt inside the polymer membrane deteriorates the membrane by generating radicals, so the degradation rate of the membrane of Pt/C MEA with a high Pt deposition rate was higher than Pt-Co/C MEA. When the Pt-Co/C catalyst was used, the electrode durability was improved, and the amount of Pt deposited on the membrane was also reduced, thereby improving the electrochemical durability of the membrane.

• Research in Plant Disease
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• v.29 no.4
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• pp.345-362
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• 2023

Anthracnose, caused by the Colletotrichum genus, comprises a significant number of plant pathogens and poses a major threat to fruit production worldwide, including South Korea. Colletotrichum species were identified associated with anthracnose in fruits such as apple, persimmon, plum, peach, jujube, walnut, and grape. A polyphasic approach, including morphology, multigene phylogenetics, and pathogenicity testing, was used. Additionally, the in-vitro sensitivity of identified Colletotrichum species to common fungicides was also evaluated. A total of nine Colletotrichum species within two complexes, namely gloeosporioides and acutatum, have been identified as the causal agents of anthracnose in common fruits in South Korea. In the gloeosporioides complex, we found Colletotrichumaenigma, C. fructicola, C. gloeosporioides, C. horii, C. siamense, and C. viniferum. Meanwhile, in the acutatum complex, C. fioriniae, C. nymphaeae, and C. orientalis were identified. Notably, C. fructicola, C. siamense, C. fioriniae, and C. nymphaeae were reported for the first time from apple, C. siamense, C. fioriniae and C. nymphaeae from plum, C. siamense, C. fructicola, and C. fioriniae frompeach, C. siamense and C. horii from persimmon, C. fioriniae from Omija (Schisandra), C. orientalis from walnut, C. nymphaeae from jujube, and C. aenigma, C. fructicola, and C. siamense fromgrape. Fungicide sensitivity tests revealed significant variation in the EC₅₀ values among specific Colletotrichum species when exposed to different fungicides. Moreover, the same Colletotrichum species isolated from different host plants displayed varying sensitivity to the same fungicide.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.624-632
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• 1989

Lipids of Liza carinata roe were extracted and separated into detailed lipid classes by column chromatography. About 57-62% of the total lipids consisted of wax esters in which saturated and unsaturated fatty alcohols combined with fatty acids with up to six double bonds. Between the even-numbered wax ester peaks in gas-liquid chromatography, ones with odd chain lengths such as C31, C33 and C35 were eluted in appreciable amounts. Isomers composed of different fatty acids and alcohols at a given chain length were not resolved on 1.5% OV-17 column. The principal component of wax esters in sample A were C32, C34 and C30 (45.0%, 19.2%, and 12.2%), followed by C36 and C38 length (9.5% and 4.7%), while those in sample B were mainly occupied by C34, C32 and C36 length (36.3%, 31.4% and 14.5%) with minor components C30 and C38 length (5.2%, and 3.4%). The wax esters were not a random combination of constituent fatty acids and alcohols. With increase in boiling temperature the wax esters increased slightly in viscosity over the unboiled, showing a tendency toward randomness, and finally were completely randomized at $360^{\circ}C$ for 40 minutes. The enzymes involved in wax ester biosynthesis seemed to have high selectivity for chain length of fatty acids and alcohols.

• Korean Journal of Mathematics
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• v.14 no.2
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• pp.169-183
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• 2006

In this paper, we define and study the C-integral and the strong C-integral of functions mapping an interval [a,b] into a Banach space X. We prove that the C-integral and the strong C-integral are equivalent if and only if the Banach space is finite dimensional, We also consider the property of primitives corresponding to Banach-valued functions with respect to the C-integral and the strong C-integral.

• Bulletin of the Korean Mathematical Society
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• v.47 no.2
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• pp.319-339
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• 2010

In this paper, we prove that if $f^nf'\;-\;P$ and $g^ng'\;-\;P$ share 0 CM, where f and g are two distinct transcendental meromorphic functions, $n\;{\geq}\;11$ is a positive integer, and P is a nonzero polynomial such that its degree ${\gamma}p\;{\leq}\;11$, then either $f\;=\;c_1e^{cQ}$ and $g\;=\;c_2e^{-cQ}$, where $c_1$, $c_2$ and c are three nonzero complex numbers satisfying $(c_1c_2)^{n+1}c^2\;=\;-1$, Q is a polynomial such that $Q\;=\;\int_o^z\;P(\eta)d{\eta}$, or f = tg for a complex number t such that $t^{n+1}\;=\;1$. The results in this paper improve those given by M. L. Fang and H. L. Qiu, C. C. Yang and X. H. Hua, and other authors.

• Transactions on Electrical and Electronic Materials
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• v.10 no.4
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• pp.131-134
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• 2009

The electrical properties and the microstructure of nitrogen-doped poly 3C-SiC films used for micro thermal sensors were studied according to different thicknesses. Poly 3C-SiC films were deposited by LPCVD (low pressure chemical vapor deposition) at $900^{\circ}C$ with a pressure of 4 torr using $SiH_2Cl_2$ (100%, 35 sccm) and $C_2H_2$ (5% in $H_2$, 180 sccm) as the Si and C precursors, and $NH_3$ (5% in $H_2$, 64 sccm) as the dopant source gas. The resistivity of the poly SiC films with a 1,530 ${\AA}$ thickness was 32.7 ${\Omega}-cm$ and decreased to 0.0129 ${\Omega}-cm$ at 16,963 ${\AA}$. The measurement of the resistance variations at different thicknesses were carried out within the $25^{\circ}C$ to $350^{\circ}C$ temperature range. While the size of the resistance variation decreased when the films thickness increased, the linearity of the resistance variation improved. Micro heaters and RTD sensors were fabricated on a $Si_3N_4$ membrane by using poly 3C-SiC with a 1um thickness using a surface MEMS process. The heating temperature of the SiC micro heater, fabricated on 250 ${\mu}m$${\times}$250 ${\mu}m$ $Si_3N_4$ membrane was $410^{\circ}C$ at an 80 mW input power. These 3C-SiC heaters and RTD sensors, fabricated by surface MEMS, have a low power consumption and deliver a good long term stability for the various thermal sensors requiring thermal stability.

• Journal of Korean Neurosurgical Society
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• v.64 no.6
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• pp.913-921
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• 2021

Objective : Accurate measurement of T1 slope (a component of T1s minus cervical lordosis [CL]) is often constrained by anatomical limitations. In this situation, efforts should be made to find the exact meaning of T1s-CL and whether there are any alternatives to it. Methods : We enrolled 117 patients who received two-level anterior cervical discectomy and fusion (ACDF). Occipital slope, C2 slope (C2s), C7 slope (C7s), T1, O-C2 angle (O-C2A), C2-7 angle (C2-7A), O-C7 angle (O-C7A), T1s-CL, C7-T1 angle (C7-T1A), and C2-7 sagittal vertical axis were measured. We determined 16° (T1s-CL) as the reference point for dividing subjects into the mismatch group and the balance group, and a comparative analysis was performed. Results : The mean value of C7-T1A was constantly maintained within 2.6° peri-operatively. In addition, C2s and T1s-CL showed the same absolute change (Δ|0.8|°). The mean values of T1s-CL of the mismatch and balance groups were 23.0° and 7.6°, respectively. The five factors with the largest differences between the two groups were as follows : C2s (Δ13.3°), T1s-CL (Δ15.4°), O-C2A (Δ8.7°), C2-7A (Δ14.7°), and segmental angle (Δ7.9°) before surgery. Only four factors showed statistically significant change between the two groups after ACDF : T1s-CL (Δ4.0° vs. Δ0.2°), C2s (Δ3.2° vs. Δ0.7°), O-C2A (Δ2.6° vs. Δ1.3°), C2-7A (Δ6.3° vs. Δ1.3°). A very strong correlation between T1s-CL and C2s was also found (r=|0.88-0.96|). Conclusion : C2s itself may be the essential key to represent T1s-CL. The amounts and directions of change of these two factors (T1s-CL and C2s) were also almost identical. The above phenomenon was re-confirmed once again through the correlation analysis.