• Applied Chemistry for Engineering
• /
• v.4 no.4
• /
• pp.814-822
• /
• 1993

To improve the solubility and adhesion strength of diamine-quinone polymers, urethane group was introduced into the polymer backbone. Urethane group containing polymeric diamines(UDA) were prepared firstly by the decarboxylation of the NCO group in NCO terminated prepolymer obtained from the reaction of MDI and 1.6-hexandiol. The reaction mole ratio of NCO/OH was changed from 1.2 to 2.1 to increase the molecular weight of diamine. From the addition reaction of UDA and p-benzoquinone in THF or DMSO solvent, five kinds of urethane group containing diamine/quinone polymers(PUAQ) were prepared according to the diamine used. IR, NMR, UV-visible spectroscopy and GPC were used to characterize the molecular structure and molecular weight of UDAs and PUAQs. Thermal analysis of polymer by DSC and TGA were carried out according to the molecular weight differency. Also solubility test of UDA and PUAQ with 10 different solvents were carried out to predict the coacting property of the polymers.

• Journal of the Korea Furniture Society
• /
• v.21 no.3
• /
• pp.237-247
• /
• 2010

This research was carried out to examine the properties of black charcoal board, in order to find the proper manufacturing condition for the black charcoal-board made of the charcoal. The charcoal in this study was distillated from domestic wood waste, and it were also the purpose of this study to see if the black charcoal-board has the advantageous properties of charcoal as a well-being building material against the sick house problem. Domestic wood waste was consisted of MDF 40%, PB 30%, plywood 15% and wood 15%, respectively. Black charcoal board was produced by hot pressing with following conditions; temperature $170^{\circ}C$, three stage pressing cycle of $40-10-40\;kgf/cm^2$(1min.-2.5min.-5min.) and non formaldehyde adhesives [P15%+M5%:MDI(M), poly vinyl acetate emulsion(P). Fine mixed particle size [#6-12(16.9%), #12-18(16.7%), #12-40(47.2%), #40-60(9.5%), #60-100(5.9%), less than #100(3.8%)] gave better results than larger particle size [over #6(33.8%), #12-18(17.7%), #12-40(37.7%), #40-60(6.4%), #60-100(2.6%), less than #100(1.8%)]. Final moisture content of the mat was best at 36%. Black charcoal-board showed less MOR and IB(internal bond), more WA(water absorption) than that of white charcoal-board. Black charcoal board showed not only the same gas adsorption and dimensional stability as white charcoal board but also good cutting, nailing and drilling for indoor environment systems.

• Tuberculosis and Respiratory Diseases
• /
• v.44 no.5
• /
• pp.1063-1071
• /
• 1997

Backgroung : The efficacy of oral corticosteroids in the treatment of chronic asthma is undisputed, but their long-term use is associated with adverse side-effects, including supression of the hypothalamic-pituitary adrenal axis function, osteoporosis, weight gain, hypertension and impaired glucose tolerance. The introduction of inhaled corticosteroids in the early 1970's represented a significant therapeutic advance in the management of asthma, since these compounds combined high topical potency with low systemic activity. Fluticasone propionate is a new topically active synthetic glucocorticosteroid that combinds a high degree of efficacy with negligible systemic bioavailability. This study was perfomed to determine the effect of inhaled fluticasone propionate on the adreocortical supression in patients with bronchial asthma or chronic obstructive pulmonary disease. Method : The adrenocortical function was assessed by measurement of plasma cortisol concentration at 8 o'clock in morning and free cortisol in 24 hour urine collection at interval. Absolutely, no steroid was taken during pretreatment period of 10days. There after each subject inhaled fluticasone aerosol, in daily doses of 500 or 1000micrograms for 12days. The dose was delivered by metered dose inhaler(MDI). Results : The serum cortisol and 24hour urinary free cortisol were not decreased during the treatment period in patients with inhaled fluticasone propionate in daily doses of 500 micrograms. In contrast, serum cortisol was significantly decreased on 9th and 12th day(p less than 0.05). And, 24hour urinary free cortisol was also significantly decreased on 3rd and 12th day of treatement period(p less than 0.05) in patients with inhaled fluticasone in daily doses of 1000 micrograms. Conclusion : These results suggested that endogenous cortisol secretion was not supressed after short-term inhalation of fluticasone in daily dose of 500 micrograms, but in daily dose of 1000 micrograms, the endogenous cortisol secretion was supressed.

• Clinical and Experimental Pediatrics
• /
• v.48 no.8
• /
• pp.826-831
• /
• 2005

Purpose : This study is directed to evaluate standardized developmental test performances of infants and children who, as fetuses, had mild isolated cerebral ventriculomegaly diagnosed by ultrasound. Methods : All prenatal sonographic findings from 2001 to 2002 were evaluated. Live isolated mild ventriculomegaly(IMVM) of 10-15 mm were observed in 95 cases(1.1 percent). Standardized developmental testing of 40 cases of IMVM and 36 cases in a comparison group were offered to parents Both groups of children were adjusted to normal antepatum subjects with respect to sex, race, indication for ultrasound and gestational age at the time of ultrasound. Test of cognitive and motor development(Bayley Scales of Infant Development, Second Edition; BSID-II) were administered by developmental examiners. Results : Forty cases and 34 comparison sujects completed the testing. The IMVM and comparison groups were similar with respect to parental age, gestational age, birth weight, familial socioeconomic status. The IMVM subjects scored lower than the comparison group on both the BSID-II, but there was not statistically significant. differences; metal development index(MDI)($92.7{\pm}12.9$ vs $94.7{\pm}14.1$, P=0.47) and psychomotor development index(PDI)($100.3{\pm}14.1$ vs $101.3{\pm}10.7$, P=0.75). Eleven cases(27.5 percent) of IMVM group and five cases(14.7 percent) of the comparison group were developmentally delayed, but most cases in both groups showed mild delays. Resolution or lack of progression, lateral ventricle diameter ${\leq}12mm$ and females were associated with better scores, but there were not statistically significant. Polarity, and head circumference were not related to later development. Conclusion : This study show children with MIVM did not delay performance in the developmental test, but we might suggest a tendency to increase the risk of mild developmental delay.

• Neonatal Medicine
• /
• v.17 no.1
• /
• pp.64-74
• /
• 2010

Purpose : The aim of this study was to determine the risk factors, clinical characteristics and prognosis for the development of periventricular leukomalacia (PVL) in preterm infants according to the extent and site of the PVL. Methods : The medical records of infants (under 36 weeks of gestational age) delivered from January 1999 to December 2008 were reviewed. Twenty-five preterm infants with were PVL were diagnosed by brain magnetic resonance imaging (MRI) and an addition 50preterm infants with no brain lesions were enrolled in this study. The perinatal and neonatal risk factors for the development of PVL was determine in these infants. Mental and Psychomotor Developmental Indices (MDI, PDI) were assessed by a clinical psychologist using the Bayley Scales of Infant Development II. We compared the differences of the clinical characteristics and prognosis according to brain MRI findings. Results : Maternal fever, young maternal age, extended oxygen use, hypotension within the first week of birth, use of inotropics within the first week of birth, and respiratory distress syndrome were the risk factors associated with PVL (P <0.05). In the multivariate analysis, maternal fever and extended oxygen use were statistically significant independent risk factors (P <0.05). The mean MDI and PDI scores of the PVL group (74.4$\pm$ 27.8 and 58.0$\pm$17.7) were significantly lower than those of the control group (103.5$\pm$8.9 and 101.7$\pm$16.1, P <0.05). Conclusion : Maternal fever and extended oxygen use were independent risk factors for PVL. We should pay attention to infants who had the risk factors and follow them up closely by brain imaging study and Bayley Scales of Infant Development II.

• Transactions of the KSME C: Technology and Education
• /
• v.2 no.2
• /
• pp.73-80
• /
• 2014

Drug delivery in human upper airway was studied by the numerical simulation of oral airflow. We created an anatomically accurate upper airway model from CT scan data by using a medical image processing software (Mimics). The upper airway was composed of oral cavity, pharynx, larynx, trachea, and second generations of branches. Thin sliced CT data and meticulous refinement of model surface under the ENT doctor's advice provided more sophisticated nasal cavity models. With this 3D upper airway models, numerical simulation was conducted by ANSYS/FLUENT. The steady inspiratory airflows in that model was solved numerically for the case of flow rate of 250 mL/s with drug-laden spray(Q= 20, 40, 60 mL/s). Optimal parameters for mechanical drug aerosol targeting of predetermined areas was to be computed, for a given representative upper airways. From numerical flow visualization results, as flow-rate of drug-laden spray increases, the drag spray residue in oral cavity was increased and the distribution of drug spray in trachea and branches became more homogeneous.

• Tuberculosis and Respiratory Diseases
• /
• v.52 no.5
• /
• pp.529-538
• /
• 2002

Background : Many clinicians are reluctant to prescribe systemic corticosteroids to manage an asthmatic attack because of many complications such as osteoporosis, cushing's syndrome, diabetes, hypertension and bleeding tendency. The use of nebulized budesonide may be of value in some infants, old men, and in particular adult asthmatic patients who complain of severe dyspnea. A clinical validation and steroid-sparing effect of nebulized budesonide in asthmatic adults and COPD were evaluated, and the short-term effects of budesonide use on the HPA axis were assessed. Materials and Methods : Study A was prospectively done with 41 patients diagnosed with pure asthma and 30 patients diagnosed with COPD (including asthmatic component) in Soonchunhyang Hospital, Chunan from June. 2000 to Sep. 2001. They were treated with nebulized budesonide including systemic steroids (Group 1), a budesonide tubuhaler including a systemic steroid (Group 2), or only the systemic steroid(Group 3). The peak flow rate, arterial blood gas in room air, pulmonary function test, symptom scoring, steroid amount and hospital stay were analyzed. Study B was conducted with 19 patients to evaluate the short-term effects on the HPA axis of treatment with nebulized budesonide 1mg twice daily and a budesonide turbuhaler 5 puffs twice daily. The adrenal function was assessed prior to budesonide inhalation and after 7 days of budesonide inhalation. Results : In the pure asthmatic patients, the mean value of the symptoms (dyspnea, wheezing, cough, night asthma) or the arterial BGAs, total amounts of steroid or hospital stay and the difference in the results of the pulmonary function tests or peak expiratory flow rate were similar in the three groups. In COPD with an asthmatic component, there were no significant differences among the three groups. Although nebulized budesonide suppressed HPA function,(p=0.006) the HPA responses from the nebulized budesonide and turbuhaler budesonide were similar (p=0.288) Conclusion : This result suggests that systemic steroid should only be made available for acute asthmatic patients irrespective of the inhaled budesonides. Nebulized budesonide at the therapeutic dose has similar effects on the HPA axis compared to that of turbuhaler budesonide.