• Research in Plant Disease
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• v.17 no.1
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• pp.78-81
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• 2011

Soft rot caused by Rhizopus oryzae occurred on unshiu orange (Citrus unshiu Marc.) sampled from commercial markets in Jinju, Korea, 2010. The first symptom of soft rot on orange is a water-soaked appearance of the affected tissue. The infected parts later disintegrated into a mushy mass of disorganized cells followed by rapid softening of the diseased tissue. The lesion on orange was rapidly softened and rotted, then became brown or dark brown. Optimum temperature for mycelial growth of the causal fungus on potato dextrose agar was $30^{\circ}C$ and growth was still apparent at $37^{\circ}C$. Sporangiophores were $6{\sim}20\;{\mu}m$ in diameter. Sporangia were globose and $40{\sim}200\;{\mu}m$ in size. The color of sporangia was brownish-grey to blackish-grey at maturity. Sporangiospores were sub-globose, brownish- black streaked and $4{\sim}10\;{\mu}m$ in size. Columella were globose to sub-globose and $85{\sim}120\;{\mu}m$ in size. On the basis of mycological characteristics, pathogenicity test, and the ITS sequence analysis, the causal fungus was identified as Rhizopus oryzae. To our knowledge, this is the first report of soft rot caused by R. oryzae on unshiu orange in Korea.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.655-668
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• 2012

Foliar diseases are major constraints to profitable organic tomato production. Especially, powdery mildew, leaf mold and gray mold of tomato occur severely on organic cultured tomatoes in Korea. This study was conducted to develop organic tomato cultivation technology using environmental-friendly disease control methods (resistance cultivar planting, air circulation fan installation, oil-egg yolk mixtures, and microbial agents). When tomatoes were cultivated in plastic film house installed with air circulation fan, daily range of temperature was decreased by $2{\sim}7^{\circ}C$, average relative humidity was decreased by 1~5% compared to those in plastic house without air circulation fan. Consequently, incidence of tomato leaf mold and tomato gray mold was reduced by 55.0% and 24.4%, respectively. Control effect of microbial agents and oil-egg yolk mixtures against major tomato diseases was examined in plastic house. As a result, the control value of microbial agents against tomato gray mold and tomato leaf mold showed at the range of 49.0~55.9 %(gray mold) and 39.2~58.2%(leaf mold), respectively. The control value of oilegg yolk mixtures against tomato powdery mildew showed 97.6%. Fifteen tomato cultivars were evaluated for disease resistance against leaf mold and powdery mildew in organically cultivated tomato field. Among 15 tomato cultivars, seven cultivars including 'Super-top' were found to be high resistant to tomato leaf mold. Also 'Powerking', one of fifteen tomato cultivars, showed to be high resistant to tomato powdery mildew.

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.627-638
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• 1992

PPG and BPA-type polyurethane prepolymers(NCO terminated) were obtained from bisphenol A and four types of PPG, having different molecular weight and numbers of functional groups. PPG and BPA-type polyurethane dimethacrylates were synthesized by reacting PPG and BPA-type polurethane prepolymer with 2-HEMA respectively. PPG-type polyurethane dimethacrylates were formulated with initiator(CHP), inhibitor(hydroquinone) and reactive diluent(TEGDMA). The effect of formulation on the torque changes was studied. Four kinds of PPG-type polyurethane dimethacrylates, having different molecular weight and numbers of functional group, were formulated with the same amount of CHP, TEGDMA and hydroquinone. The effects of the molecular weight of PPG-type polyurethane dimethacrylate and functional group numbers of PPG-type polyurethane dimethacrylates on the torque were investigated. These results showed that the torque of PPG-type polyurethane dimethacrylates, having same numbers of functional group, increased with decreasing molecular weight of dimethacrylates and torque of PPG-type polyurethane dimethacrylate, having similar molecular weight, was increased with increasing the number of fuctional group. The glass-transition temperature(Tg) of gels obtained by thermosetting cure for the four kinds of PPG-type polyurethane dimethacrylates were measured by DSC and molecular weights between cross-links(Mc) were calculated from Tg changes.

• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.211-219
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• 1997

Liquid or gas phase alkylation of isobutane with 1-butene for i-octane production was carried out over Cs- or $NH_4$-exchanged $H_3PW_{12}O_{40}$. Pretreatment temperature of the catalyst played an important role on the catalytic activity of heteropoly acids in the liquid phase alkylation. Cation-exchanged $H_3PW_{12}O_{40}$ showed a better total yield and i-octane selectivity than the mother acid in the liquid phase alkylation, and $(NH_4)_{2.5}H_{0.5}PW_{12}O_{40}$ was more efficient than $Cs_{2.5}H_{0.5}PW_{12}O_{40}$ in terms of i-octane selectivity. It was found that the acidic property (deactivation of acid sites) of the catalyst was closely related to the catalytic activity of Cs- or $NH_4$-exchanged $H_3PW_{12}O_{40}$ in the gas phase alkylation. $C_5-C_7$ were mainly formed in the early stage of gas phase alkylation due to the strong acidic property of the catalyst, whereas $C_8$ and $+C_9$ were mainly produced as the reaction proceeded due to the deactivation of acid sites. $Cs_{2.5}H_{0.5}PW_{12}O_{40}$ showed the highest total yield in the gas phase alkylation among the catalysts examined.

• Journal of Life Science
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• v.14 no.1
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• pp.131-140
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• 2004

T7 bacteriophage gp4 is the replicative DNA helicase that unwinds double-stranded DNA by utilizing dTTP hydrolysis energy. The quaternary structure of the active form of T7 helicase is a hexameric ring with a central channel. Single-stranded DNA passes through the central channel of the hexameric ring as the helicase translocates $5'\rightarrow3'$ along the single-stranded DNA. The DNA unwinding was measured by rapid kinetic methods and showed a lag before the single-stranded DNA started to accumulate exponentially. This behavior was analyzed by a kinetic stepping model for the unwinding process. The observed lag phase increased as predicted by the model with increasing double-stranded DNA length. Trap DNA added in the reaction had no effect on the amplitudes of double-stranded DNA unwound, indicating that the $\tau7$ helicase is a highly processive helicase. Global fitting of the kinetic data to the stepping model provided a kinetic step size of 10-11 bp/step with a rate of $3.7 s^{-1}$ per step. Both the mechanism of DNA unwinding and dTTP hydrolysis and the coupling between the two are unaffected by temperature from $4∼37^{\circ}C$. Thus, the kinetic stepping for dsDNA unwinding is an inherent property of tile replicative DNA helicase.

• Journal of Chest Surgery
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• v.26 no.7
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• pp.513-520
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• 1993

Surgical treatment of aneurysm or dissection involving the ascending aorta and aortic arch still poses one of the most complicated technical and tactical challenges in surgery. The use of total circulatory arrest[TCA] with profound hypothermia in the surgical treatment of aneurysmal dissection involving the ascending aorta and aortic arch has been reported as popular surgical methods. However, the safe period of prolonged circulatory arrest with hypothermia remains controversial and ischemic damage to the central nervous system and uncontrollable perioperative bleeding have been the major problem. We have found profound hypothermic circulatory arrest with retrograde cerebral perfusion via the superior vena cava to achieve cerebral protection. We experiment the aortic anastomosis in 7 adult mongrel dogs, using profound hypothermic circulatory arrest with continuous retrograde cerebral perfusion[RGCP] via superior vena cava. We also studied the extent of cerebral protection using above surgical methods, by gas analysis of retrograde cerebral perfusion blood and returned blood of aortic arch, preoperative, intraoperative and postoperative electroencephalography and microscopic findings of brain tissue. The results were as follows: 1. The cooling time ranged from 15 minutes to 24 minutes[19.71$\pm$ 3.20 minutes] ; Aorta cross clamp time ranged from 70 minutes to 89 minutes[79.86 $\pm$ 7.54 minutes] ; Rewarming time ranged from 35 minutes to 47 minutes[42.86$\pm$ 4.30 minutes] ; The extracorporeal circulation time ranged from 118 minutes to 140 minutes[128.43$\pm$ 8.98 minutes] [Table 2]. 2. The oxygen content in the oxygenated blood after RGCP was 12.66$\pm$ 1.25 ml/dl. At 5 minutes after the initiation of RGCP, the oxygen content of returnedlood was 7.58$\pm$ 0.21 ml/dl, and at 15 minutes 7.35$\pm$ 0.17 ml/dl, at 30 minutes 7.20$\pm$ 0.19 ml/dl, at 60 minutes 6.63$\pm$ 0.14 ml/dl [Table 3]. 3. Intraoperative electroencephalographic finding revealed low amplitude potential during hypothermia, and no electrical impulse throughout the period of circulatory arrest and RGCP. Electrical activity appeared after reperfusion, and the electroencephalographic reading also recovered rapidly as body temperature returned to normal [Fig. 2]. 4. The microscopic finding of brain tissue showed widening of the interfibrillar spaces. But there was no evidence of tissue necrosis or hemorrhage [Fig. 3]. We concluded the retrograde cerebral perfusion during hypothermic circulatory arrest is a simplified technique that may have a excellent brain protection.

• Journal of Chest Surgery
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• v.12 no.3
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• pp.281-288
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• 1979

For years, physicians and anatomists have been interested in the heart that has one functioning ventricle. Various terms have been suggested for this entity including single ventricle, common ventricle, double-inlet left ventricle, cor biatriatum triloculare, and primitive ventricle. In this report, the term "single ventricle" is utilized as suggested by Van Praagh, and is defined as that congenital cardiac anomaly in which a common or separate atrioventricular valves open into a ventricular chamber from which both great arterial trunks emerge. An outlet chamber, or infundibulum, may or may not be present and give rise to the origin of either of the great arteries. This definition excludes the entity of mitral and tricuspid atresia. An 11 year old cyanotic boy was admitted chief complaints of exertional dyspnea and frequent upper respiratory infection since 2 weeks after birth. He was diagnosed as inoperable cyanotic congenital heart disease, and remained without any corrective treatment up to his age of 11 year when he suffered from aggravation of symptoms and signs of congestive heart failure for 2 months before this admission. On 22nd of May 1979, he was admitted for total corrective operation under the impression of tricuspid atresia suggested by a pediatrician. Physical check revealed deep cyanosis with finger and toe clubbing, and grade V systolic ejection murmur with single second heart sound was audible at the left 3rd intercostal space. Development was moderate in height [135 cm] and weight[28Kg]. Routine lab findings were normal except increased hemoglobin [21.1gm%], hematocrit [64 %], and left axis deviation with left ventricular hypertrophy on EKG. Cardiac catheterization and angiography revealed 1-transposition of aorta, pulmonic valvular stenosis, double inlet of a single ventricle with d-loop, and normal atriovisceral relationship [Type III C solitus according to the classification of Van Praagh]. At operation, longitudinal incision at the outflow tract of right ventricle in between the right coronary artery and its branch [LAD from RCA] revealed high far anterior aortic valve which had fibrous continuity with mitral annulus, and pulmonic valve was stenotic up to 4 mm in diameter positioned posterolaterally to the aorta. Ventricular septum was totally defective, and one markedly hypertrophied moderator band originated from crista supraventricularis was connected down to the imaginary septum of the ventricular cavity as a pseudoseptum of the ventricle. Size of the defect was 3X3 cm2 in total. Patch closure of the defect with a Teflon felt of 3.5 x 4 cm2 was done with interrupted multiple sutures after cut off of the moderator band, which was resutured to the artificial septum after reconstruction of the ventricular septum. Pulmonic valvotomy was done from 4 mm to 11 mm in diameter thru another pulmonary arteriotomy incision, and right ventriculotomy wound was closed reconstructing the right ventricular outflow tract with pericardial autograft of 3 x 4 cm2. Atrial septal defect of 2 cm in diameter was closed with 3-0 Erdeck suture, and atrial wall was sutured also when rectal temperature reached from 24`C to 35.5`C. Complete A-V block was managed with temporary external pacemaker with a pacing rate of 110/min. thru myocardial wire, and arterial blood pressure of 80/50 mmHg was maintained with Isuprel or Dopamine dripping under the CVP of 25-cm saline. Consciousness was recovered one hour after the operation when his blood pressure reached 100 /70 mmHg, but vital signs were not stable, and bleeding from the pericardial drainage and complete anuria were persisted until his heart could not capture the pacemaker impulse, and patient died of low output syndrome 320 min after the operation.

• Journal of Chest Surgery
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• v.12 no.3
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• pp.289-296
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• 1979

For years, physicians and anatomists have been interested in the heart that has one functioning ventricle. Various terms have been suggested for this entity including single ventricle, common ventricle, double-inlet left ventricle, cor biatriatum triloculare, and primitive ventricle. In this report, the term "single ventricle" is utilized as suggested by Van Praagh, and is defined as that congenital cardiac anomaly in which a common or separate atrioventricular valves open into a ventricular chamber from which both great arterial trunks emerge. An outlet chamber, or infundibulum, may or may not be present and give rise to the origin of either of the great arteries. This definition excludes the entity of mitral and tricuspid atresia. An 11 year old cyanotic boy was admitted chief complaints of exertional dyspnea and frequent upper respiratory infection since 2 weeks after birth. He was diagnosed as inoperable cyanotic congenital heart disease, and remained without any corrective treatment up to his age of 11 year when he suffered from aggravation of symptoms and signs of congestive heart failure for 2 months before this admission. On 22nd of May 1979, he was admitted for total corrective operation under the impression of tricuspid atresia suggested by a pediatrician. Physical check revealed deep cyanosis with finger and toe clubbing, and grade V systolic ejection murmur with single second heart sound was audible at the left 3rd intercostal space. Development was moderate in height [135 cm] and weight[28Kg]. Routine lab findings were normal except increased hemoglobin [21.1gm%], hematocrit [64 %], and left axis deviation with left ventricular hypertrophy on EKG. Cardiac catheterization and angiography revealed 1-transposition of aorta, pulmonic valvular stenosis, double inlet of a single ventricle with d-loop, and normal atriovisceral relationship [Type III C solitus according to the classification of Van Praagh]. At operation, longitudinal incision at the outflow tract of right ventricle in between the right coronary artery and its branch [LAD from RCA] revealed high far anterior aortic valve which had fibrous continuity with mitral annulus, and pulmonic valve was stenotic up to 4 mm in diameter positioned posterolaterally to the aorta. Ventricular septum was totally defective, and one markedly hypertrophied moderator band originated from crista supraventricularis was connected down to the imaginary septum of the ventricular cavity as a pseudoseptum of the ventricle. Size of the defect was 3X3 cm2 in total. Patch closure of the defect with a Teflon felt of 3.5 x 4 cm2 was done with interrupted multiple sutures after cut off of the moderator band, which was resutured to the artificial septum after reconstruction of the ventricular septum. Pulmonic valvotomy was done from 4 mm to 11 mm in diameter thru another pulmonary arteriotomy incision, and right ventriculotomy wound was closed reconstructing the right ventricular outflow tract with pericardial autograft of 3 x 4 cm2. Atrial septal defect of 2 cm in diameter was closed with 3-0 Erdeck suture, and atrial wall was sutured also when rectal temperature reached from 24`C to 35.5`C. Complete A-V block was managed with temporary external pacemaker with a pacing rate of 110/min. thru myocardial wire, and arterial blood pressure of 80/50 mmHg was maintained with Isuprel or Dopamine dripping under the CVP of 25-cm saline. Consciousness was recovered one hour after the operation when his blood pressure reached 100 /70 mmHg, but vital signs were not stable, and bleeding from the pericardial drainage and complete anuria were persisted until his heart could not capture the pacemaker impulse, and patient died of low output syndrome 320 min after the operation.

• Journal of Chest Surgery
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• v.44 no.3
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• pp.215-219
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• 2011

Background: Selective antegrade perfusion via axillary artery cannulation along with circulatory arrest under deep hypothermia has became a recent trend for performing surgery on the ascending aorta and aortic arch and when direct aortic cannulation is not feasible. The authors of this study tried using moderate hypothermia with right brachial and femoral artery perfusion to complement the pitfalls of single axillary artery cannulation and deep hypothermia. Materials and Methods: A retrospective analysis was performed on 36 patients who received ascending aorta or aortic arch replacement between July 2005 and May 2010. The adverse outcomes included operative mortality, permanent neurologic dysfunction and temporary neurologic dysfunction. Results: Of these 36 patients, 32 (88%) were treated as emergencies. The mean age of the patients was 61.9 years (ranging from 29 to 79 years) and there were 19 males and 17 females. The principal diagnoses for the operation were acute type A aortic dissection (31, 86%) and aneurysmal disease without aortic dissection (5, 14%). The performed operations were ascending aorta replacement (9, 25%), ascending aorta and hemiarch replacement (13, 36%), ascending aorta and total arch replacement (13, 36%) and total arch replacement only (1, 3%). The mean cardiopulmonary bypass time was $209.4{\pm}85.1$ minutes, and the circulatory arrest with selective antegrade perfusion time was $36.1{\pm}24.2$ minutes. The lowest core temperature was $24{\pm}2.1^{\circ}C$. There were five deaths within 30 post-op days (mortality: 13.8%). Two patients (5.5%) had minor neurologic dysfunction and six patients, including three patients who had preoperative cerebral infarction or unconsciousness, had major neurologic dysfunction (16.6%). Conclusion: When direct aortic cannulation is not feasible for ascending aorta and aortic arch replacement, the right brachial and femoral artery can be used as arterial perfusion routes with the patient under moderate hypothermia. This technique resulted in acceptable outcomes.

• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.120-120
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• 1998

Boron nitride (BN) films have attracted a growing interest for a variety of t technological applications due to their excellent characteristics, namely hardness, c chemical inertness, and dielectrical behavior, etc. There are two crystalline phases 1551; of BN that are analogous to phases of carbon. Hexagonal boron nitride (h-BN) has a a layered s$\sigma$ucture which is spz-bonded structure similar to that of graphite, and is t the stable ordered phase at ambient conditions. Cubic boron nitride (c-BN) has a z zinc blende structure with sp3-bonding like as diamond, 따ld is the metastable phase a at ambient conditions. Among of their prototypes, especially 삼Ie c-BN is an i interesting material because it has almost the same hardness and thermal c conductivity as di없nond. C Conventionally, significant progress has been made in the experimental t techniques for synthesizing BN films using various of the physical vapor deposition 밍ld chemical vapor deposition. But, the major disadvantage of c-BN films is that t they are much more difficult to synthesize than h-BN films due to its narrow s stability phase region, high compression stress, and problem of nitrogen source c control. Recent studies of the metalorganic chemical vapor deposition (MOCVD) of I III - V compound have established that a molecular level understanding of the d deposition process is mandatory in controlling the selectivity parameters. This led t to the concept of using a single source organometallic precursor, having the c constituent elements in stoichiometric ratio, for MOCVD growth of 삼Ie required b binary compound. I In this study, therefore, we have been carried out the growth of h-BN thin f films on silicon substrates using a single source precursors. Polycrystalline h-BN t thin films were deposited on silicon in the temperature range of $\alpha$)() - 900 $^{\circ}$C from t the organometallic precursors of Boron-Triethylamine complex, (CZHs)3N:BRJ, and T Tris(dimethylamino)Borane, [CH3}zNhB, by supersonic molecular jet and remote p plasma assisted MOCVD. Hydrogen was used as carrier gas, and additional nitrogen w was supplied by either aDlIDonia through a nozzle, or nitrogen via a remote plasma. T The as-grown films were characterized by Fourier transform infrared spectroscopy, x x-ray pthotoelectron spectroscopy, Auger electron spectroscopy, x-ray diffraction, t transmission electron diffraction, optical transmission, and atomic force microscopy.roscopy.