• Proceedings of the KSME Conference
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• 2002.08a
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• pp.831-834
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• 2002

An analytic approach is attempted to predict the amplification of turbulence in compressible flows experiencing one-dimensional and axisymmetric bulk dilatation. The variations of vortex radius and vorticity are calculated, and then the amplification of turbulence is obtained from them by tracking three representative vortices. For a one-dimensionally compressed flow, the present analysis slightly underestimates the amplification of velocity fluctuations and turbulent kinetic energy, relative to that of rapid distortion theory in the solenoidal limit. For an axisymmetrically distorted flow, the amplification of velocity fluctuations and turbulent kinetic energy depend not only on the density ratio but also on the ratio of streamwise mean velocities, which represents streamwise vortex contraction/stretching. In all flows considered, the amplification of turbulence is dictated by the mean density ratio. In the axisymmetric flow, streamwise vortex stretching/contraction, however, alters the amplification slightly.

• Communications of the Korean Mathematical Society
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• v.35 no.4
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• pp.1299-1307
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• 2020

We show that the Liechti-Strenner's example for the closed nonorientable surface in [13] minimizes the dilatation within the class of pseudo-Anosov homeomorphisms with an orientable invariant foliation and all but the first coefficient of the characteristic polynomial of the action induced on the first cohomology nonpositive. We also show that the Liechti-Strenner's example of orientation-reversing homeomorphism for the closed orientable surface in [13] minimizes the dilatation within the class of pseudo-Anosov homeomorphisms with an orientable invariant foliation and all but the first coefficient of the characteristic polynomial p(x) of the action induced on the first cohomology nonpositive or all but the first coefficient of p(x)(x ± 1)², p(x)(x² ± 1), or p(x)(x² ± x + 1) nonpositive.

• Journal of Veterinary Clinics
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• v.10 no.1
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• pp.61-64
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• 1993

A German shepherd dog, male, seven-month-old, with gastric dilatation was examined clinicopathologically and radiographically. X-ray findings showed radiopaque linear materials, which were identified a number of pieces of commercial antiparasitic collar, $Preventic^{\circledR}$(Amitraz, Virbac) by gastrotomy. The dog became good a day after removal of the materials in the stomach. It was considered that the gastric dilatation was caused by rapid absorption of the amitraz which could induce paralysis of stomach.

• Journal of The Korean Society of Emergency Medicine
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• v.29 no.5
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• pp.551-556
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• 2018

Cases of repeated acute gastric dilatations after binge eating in one patient are rarely reported. We report here a case of repeated acute gastric dilatations in a 22-year-old woman with bulimia nervosa. Her repeated acute gastric dilatations seem to have been related to superior mesenteric artery syndrome. On her last visit due to acute gastric dilatation, she underwent emergency gastric decompression surgery because of abdominal compartment syndrome; however, she eventually died because of ischemia reperfusion injury. Emergency physicians should be aware of the need to manage acute gastric dilatation in patients with eating disorder and should pay attention to the signs and distinctive clinical features of abdominal compartment syndrome.

• Toxicological Research
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• v.2 no.1
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• pp.37-50
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• 1986

This paper describes the effects of nitrofen (Hi-TOK), a herbicide on the fetuses of rats. The results were observed as follows: The internal soft tissue anomalies were classified as diaphragmatic hernia, cardiac malformation (T.G.V., V.S.D., S.V.), dilatation of ventricle in brain, dilatation of renal pelvis, underdevelopment of fetal lung, shortening of cortex length and increasing of immatured glomeruli counts in the fetal kidney. The heart and diaphragm appear to be the target organs.

• Journal of Veterinary Clinics
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• v.19 no.2
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• pp.264-267
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• 2002

Tricuspid valve dysplasia was diagnosed in 2 month-old german shepherd dog. Radiographic and echocardiographic examination was performed and they revealed severe dilatation of the right atrium, dilatation of the right ventricle, and septal leaflet tethered to the right side of the septum. On Doppler echocardiography, tricuspid valve incompetence was detected, flow velocity ranging from 3-4 m/sec. Color Doppler examination showed large turbulent jet in the right atrium.

• Tuberculosis and Respiratory Diseases
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• v.43 no.5
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• pp.701-708
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• 1996

Background : To evaluate the effect of the balloon dilatation in tuberculous bronchial stenosis, we performed balloon dilatation in 13 cases which had airway obstruction in main bronchus with the impairment of pulmonary function. Material and Methods: Thirteen women with tuberculous bronchial stenosis(9cases : left main bronchus, 4 cases: right main bronchus) underwent fluoroscopically guided balloon dilatation under the local anesthesia. Among the these patient, 9 cases were active endobronchial tuberculosis, and 4 cases were inactive. Immediate and long term follow-up(average 15.6months) assessments were done focused on change on PIT. The increase of FVC or FEV1 more than 15% after the procedure was considered effective. Complications after dilatation were evaluated in all patients. Result : 1) There were an decrease of self-audible wheezing in 75%(6/8), improvement of dyspnea in 62.5%(5/8), improvement of cough and expectoration in 50%(3/6), and improvement of chest discomfort in 50%(1/2). 2) Significant improvement of PFT was noted in 42.9%(3/7) of which respiratory symptoms duration was below 6 months. 8m, significant improvement of PFT was noted in only 25%(1/4) of which respiratory symptoms duration was above 12 months. 3) Active stage was 69.2%(9/13) and inactive was 30.8%(4/13). There was an significant improvement of PFT in 44.4%(4/9) of active stage, but, only 25%(1/4) of inactive stage was improved. 4) In 61.5%(8/13), FVC and FEV1 were increased to 35.5%, and 22.2% at post-dilatation 7 days. After 1 month later, FVC and FEV1 were increased to 54.7%, and 31.8% in 5 cases(38.5%). 4 cases in which long-term follow-up(average 19.8months) was possible the improvement of FVC, and FEV1 were 30.5%, and 10.1%. 5) Just after balloon dilatation therapy, transient leukocytosis or fever was noted in 30.8%(4/13), and blood-tinged sputum was noted in 30.8%(4/13). However, serious complication, such as pneumothorax, pneumomediastinum or mediastinitis, was not noted. Conclusion : We conclude that tuberculous bronchial stenosis, which is on active stage, and short dulation of respiratory symptoms was more effective on balloon dilatation than inactive stage or long duration of respiratory symptoms. Furthermore, balloon dilatation is easier, much less invasive and expensive than open surgery. and cryotherapy or photoresection. Because of these advantage, we think that balloon dilatation could be the first choice for treating bronchial stenosis and could be done at first in early stage if unresponsiveness with steroid therapy is observed.

• Journal of Veterinary Clinics
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• v.25 no.4
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• pp.314-316
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• 2008

Acute gastric dilatation (AGD), one of the common causes of emergency occurs in macaca monkeys that are accommodated as laboratory-housed nonhuman primates. This report introduces some cases of occurrence in raising primates. The primates revealed an acute gastric dilatation, including the histories that were trained by monkey chair, anesthetized for the study or intact case. The clinical signs were comatose condition with sever abdominal distension, dehydration, cyanosis and apnea. One case died by deterioration of systemic body condition and performed necropsy. The other cases recovered from the AGD by the emergency treatment using the gastric tube and fluid therapy. Necropsy revealed the huge stomach filled with water, gas and ingesta. This report suggests that etiologic factors of AGD may include non-specific factors like these cases, with special emphasis on the incidence and management of AGD in nonhuman primates.

• Journal of Chest Surgery
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• v.45 no.3
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• pp.141-147
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• 2012

Background: Although the aortic valve-sparing procedure has gained popularity in recent years, it still remains challenging in patients with advanced aortic regurgitation (AR). We compared the long-term outcomes of the aortic valve-sparing procedure with the Bentall operation in patients with advanced aortic regurgitation secondary to aortic root dilatation. Materials and Methods: A retrospective review of 120 patients who underwent surgery for aortic root dilatation with moderate to severe AR between January 1999 and June 2009 was performed. Forty-eight patients underwent valve-sparing procedures (valve-sparing group), and 72 patients underwent the Bentall procedure (Bentall group). The two groups' overall survival, valve-related complications, and aortic valve function were compared. Results: The mean follow-up duration was $4.9{\pm}3.1$ years. After adjustment, the valve-sparing group had similar risks of death (hazard ratio [HR], 0.61; p=0.45), and valve related complications (HR, 1.27; p=0.66). However, a significant number of patients developed moderate to severe AR in the valve-sparing group at a mean of $4.4{\pm}2.5$ years of echocardiographic follow-up (p<0.001). Conclusion: Both the Bentall operation and aortic valve-sparing procedure showed comparable long-term clinical results in patients with advanced aortic regurgitation with aortic root dilatation. However, recurrent advanced aortic regurgitation was more frequently observed following valve-sparing procedures.

• Childhood Kidney Diseases
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• v.12 no.1
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• pp.105-110
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• 2008

Renovascular hypertension results from a lesion that impairs blood flow to a part of or all, of one or both kidneys. Renal artery stenosis is the major cause of renovascular hypertension and the most common cause of treatable secondary hypertension. Recently, percutaneous transluminal renal angioplasty(PTRA) with or without stent placement, has become the preferred choice for correcting symptomatic renal artery stenosis since it is less invasive than surgical reconstruction. PTRA with balloons designed for the dilatation for the dilatation of the coronary artery can be tried in small sized renal artery stenosis. We report a case of renovascular hypertension in a 13-year-old male who had small sized renal artery stenosis. Hypertension was controlled by PTRA with balloon dilatation.