• Journal of the Korean Chemical Society
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• v.32 no.6
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• pp.520-527
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• 1988

The crystal structures of $Co^{2+}\;and\;Ag^+\;exchanged\;zeolite\; A,\; Ag_6Co_3$-A(a = 12.131(5)$\AA$) and $Ag_3Co_{4.5}$-A(a = 12.145(1)$\AA$), have been determined by single crystal X-ray diffraction techniques. Both structures were solved and refined in the cubic space group Pm3m at 21(1)$^{\circ}C$. Full-matrix leastsquares refinement converged to the final error indices of R1 = 0.045 and R2 = 0.041 for $Ag_3Co_{4.5}-A,\; and\; R1 = 0.066\; and\; R2 = 0.076\; for\; Ag_6Co_3$-A using the 258 and 189 reflections, respectively, for which I > 3$\sigma$(I). Both structures indicate that CO(Ⅱ)ions are coordinated by three framework oxygens; the Co(II) to O(3) distances are 2.118(4)$\AA$ for $Ag_3Co_{4.5}$-A and 2.106(1)$\AA$ for $Ag_6Co_3-A$, respectively. In each structure, the angle substended at Co(II), O(3)-Co(II)-O(3) is ca 120°, close to the idealized trigonalplanar value. $Co^{2+}$ ions prefer to 6-ring sites and $Ag^+$ ions prefer to 8-ring site when total number of cations is more than 8. The crystals of hydrated and dehydrated $Ag_{12-2x}Co_x-A (x > 4.5)$ had no crystalline diffraction pattern, indicating the apparent exchange limit of $Co^{2+}\; into\; Ag_{12}-A\; is\; 4.5 Co^{2+}$ ions per unit cell. $Co^{2+}$ ions hydrolyze $H_2O$ molecules and $H_3O^+$ concentraction is accumulating. These $H_3O^+$ ions destroy the zeolite structures.

• Progress in Medical Physics
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• v.14 no.2
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• pp.141-148
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• 2003

The purpose of this study is to evaluate the distribution of clusters and blood flow rate in ADHD SPECT brain blood flow images of children using statistical parametric mapping (SPM99). We studied 64 ADHD children (4-15 y, $8.03{\pm}2.57$ y. male/female:52/12) and compared them with a control group of 12 children (6-l7 y, $9.42{\pm}3.37$ y, male/female:8/4). We injected blood flow tracer $^{99m}Tc$-ethylcysteinate dimer (ECD) as a rCBF agent and took blood flow images after 30 min. by SPECT camera. In the case of hyperperfusion of rCBF in the ADHD group, we found 3 clusters clearly separated at the cingulate gyrus, Rt.cerebral occipital lobe and Lt.cerebellar post. lobe, on probability level 0.05 (P<0.05). Thirty-six ADHD patients with average hyperfusion rates between 18.72-19.30% in each cluster had more increase in blood flow than the average perfusion rate at the Rt. cerebral occipital lobe. These levels were influenced by P-value. In the case of hypoperfusion in the ADHD children, 4 decreased clusters on Lt. and Rt. cerebral frontal lobe, Lt. cerebral claustrum and Rt. cerebral, sup. temporal gyrus at P<0.01 can be seen. The average hypoperfusion rates for the ADHD children were 18.41-18.69% in each cluster, which showed more hypopefusion than the average perfusion rate at the Lt. Cerebrum inf. Frontal gyrus. The perfusion rates and the number of patients were not affected by P-value. The result of this study shows significant hyperpefusion clusters at the probability level of P:0.05 and hypoperfusion clusters at P:0.01. The number of ADHD patients in each clusters and the perfusion rate were not affected by P-value.

• Food Science and Preservation
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• v.22 no.3
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• pp.428-436
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• 2015

Five extraction conditions (AE, autoclave extraction; OE, oven extraction; HWSE, hot water and sonication extraction; HWASE, hot water acidified with 0.5% (v/v) acetic acid and sonication extraction; and BE, boiling extraction) were examined to compare the effects of different hot water extraction methods on the antioxidant properties of blueberries. The extraction yields of the AE, OE, HWSE, HWASE, and BE were 7.94%, 8.35%, 8.55% 9.15%, and 8.50%, respectively. The polyphenol and flavonoid contents of AE were 3.47 mg GAE/g and 1.59 mg RE/g, respectively, which were highest centents among others. Those of OE were ranked second to the highest. The total anthocyanin content of HWSE (5.29 mg/g) was significantly higher than that of others whereas that of AE showed the lowest content (0.96 mg/g). The order of ABTS radical and alkyl radical scavenging activities was as follows: AE > BE > OE > HWSE > HWASE. The antioxidant properties were considerably correspondent with the total polyphenol and flavonoid content. DPPH radical scavenging activity was quite high in HWSE, AE, and BE extraction, however, there were no significant differences among the five extraction methods in the aspect of $Fe^{2+}$ ion chelating activities. Moreover, AE showed the highest SOD activity, and protected the dermal fibroblast the best against $H_2O_2$-induced cytotoxicity. In conclusion, it was suggested that the autoclave extraction (AE) would be the most effective method for preparing blueberry hot water extracts with relatively high antioxidant activities.

• Clinical and Experimental Pediatrics
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• v.45 no.5
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• pp.646-653
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• 2002

Purpose : The incidence of type 2 diabetes mellitus in children has been increasing worldwide recently, which is thought to be related to the increasing prevalence of obesity. We investigated to evaluate the incidence and the characteristics of type 2 diabetes mellitus in children and also analysed the relationship between intrauterine growth retardation and type 2 diabetes mellitus. Methods : We investigated 25 children diagnosed as type 2 diabetes mellitus between March 1990 and December 2000. The analysis was performed retrospectively with medical records based on the clinical characteristics and laborotory findings. Results : Incidence of type 1 and type 2 diabetes mellitus in children has been increasing since 1990. We demonstrated an increase in the percentage of type 2 diabetes mellitus children from 5.3% in 1990 to 21.0% in 2000. Sixty eight percent of patients(17/25) were classified as obese group. Initial symptoms at first visit were polyuria, polydipsia and polyphagia 48%(12/25), asymptomatic glycosuria 40% (10/25), weight loss 8%(2/25) and obesity 4%(1/25). The mean age at diagnosis was $12.9{\pm}1.8$ years. 64%(16/25) of patients had positive family history of type 2 diabetes mellitus. Autoanti-bodies were positive in 18.1%(4/22) of patients. Twenty eight percent (7/25) of patients had an associated disease and two patients had fatty liver in association with obesity. Treatment consisted of diet, exercise, education and oral hypoglycemic agents. Three patients were treated with insulin as well as oral hypoglycemic agents because of poor blood glucose control. Long-term diabetic complications occurred in 4 patients. Intrauterine growth retardtion was found in 34.6%(9/25); 88.9% (8/9) of these patients were non-obese group. Conclusion : The increase in the incidence of type 2 diabetes mellitus in children is thought to be related to the increasing prevalence of obesity. The non-obese group of patients might be associated with intrauterine growth retardation.

• Journal of Oral Medicine and Pain
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• v.32 no.2
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• pp.177-185
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• 2007

Iatrogenic injury following dental treatments and the use of local anesthetics may cause taste disorders. The aims of this study were to investigate quantitative and qualitative changes of taste due to unilateral inferior alveolar nerve block anesthesia and further to evaluate potential effects on taste function related to anesthesia or hypoesthesia of inferior alveolar nerve, possibly occurring after dental procedure. 30 healthy volunteers in their twenties participated in this study (male to female = 1:1, mean age of $24.0{\pm}1.8$ years). Each subject received inferior alveolar nerve block anesthesia on his or her right side with 2% lidocaine HCl containing 1:100,000 epinephrine. Before and after anesthesia, electrogustometric test and chemical localized test for salty, sweet, sour and bitter tastes were performed on the eight sites in the oral cavity; right and left anterior and lateral tongue and circumvallate papilla of the tongue and soft palate. Unilateral inferior alveolar nerve anesthesia produced elevation of electrical taste threshold and reduction of intensity ratings for all 4 tastes (salty, sweet, sour and bitter) over anterior and lateral tongue and circumvallate papilla on the ipsilateral side (p<0.05). Contralateral sides exhibited decreased intensity ratings for salty and sweet taste (p<0.05) on anterior and lateral tongue while there was no significant difference in electrogustometric testing. Based on the results of this study, it is assumed that unilateral local anesthesia on inferior alveolar nerve can affect chorda tympani and glossopharyngeal nerves on the same side, leading to taste deficits. Taste intensity on the contralateral side may, in part, be deteriorated as well.

• Journal of Oral Medicine and Pain
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• v.32 no.2
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• pp.211-218
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• 2007

The purpose of this study was to compare the maximum bite forces between pre- and post-treatment related to specific diagnostic groups of TMD including masticatory muscle disorder (MMD), disc derangement (DD), joint inflammation (JI) and osteoarthritis (OA). Bite force between pre- and post-treatment was compared in 36 patients with unilateral TMD, successfully-managed in the Department of Oral Medicine, Dankook University Dental Hospital, for this study. The ratio of men to women was 7:29 and their mean age of $28.1{\pm}13.7$ years. The patients were categorized, through clinical and radiographic examination, into aforementioned 4 groups; MMD (N=18), DD (N=6), JI (N=5) and OA (N=7). The maximum bite force measurements were done at the antagonizing canines and 1st molars using a bite force recorder. Paired t-test, ANOVA, Multiple Comparison t-tests were used for statistical analysis. The results of this study showed that the maximum bite force before treatment increased after TMD treatment, which was noticeable at the canines (p=0.001 and p=0.000 for the affected and unaffected sides, respectively). In comparison related to the diagnostic groups of TMD, patients with osteoarthritis of TMJ exhibited the lowest strength while those with inflammatory disorder of TMJ had the highest strength on the affected sides. Increase of bite force after treatment was also found in each group. Significant difference between pre- and post-treatment was found at canines on the affected sides in MMD (p=0.045) and DD groups (p=0.009) while on the unaffected sides in OA group (p=0.003). Conclusively, the reduced bite force due to TMD could be recovered by conservative TMD treatment and that the difference of bite forces between pre- and post-treatment was noticeable at the canines.

• Journal of Oral Medicine and Pain
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• v.32 no.3
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• pp.283-292
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• 2007

In several treatment modalities for snoring and obstructive sleep apnea (OSA), oral appliances mainly including mandibular advancement appliance (MAA) and tongue retaining device (TRD) are recognized as a non-invasive, reversible alternative with favorable results. Tongue bulb is a major component of TRD which prevents the tongue from approaching the posterior wall of the pharynx and can be combined with MAA. Determination of tongue bulb size for the patient is important for therapeutic effect, but frequently needs time-consuming work. For effective fabrication and standardization of tongue bulbs, this study aimed to categorize tongue bulb size for healthy young men and to examine its relation with maximum retention force and with physical parameters including tongue-related variables. 36 non-snoring, asymptomatic young men with normal occlusion were voluntarily participated in this study (mean age: $24.47{\pm}2.58$ years). Experimental procedures consisted of prefabrication of tongue bulb set (20 types with a width of 27-36mm and thickness of 8 and 10 mm), determination of tongue bulb size and the maximum retention force for each subject, and measurement of physical parameters including body mass index (BMI), neck circumference and width, thickness and length of tongue. This study showed that there was significant difference of retention force among the bulb size-related groups both in upright and supine position (p<0.05) and that retention force increased with bulb size. Correlation of tongue bulb size with physical parameters was not clearly verified and there was no significant difference in retention force between upright and supine positions. Based on our results, it can be suggested that retention force relates with tongue bulb size, ultimately with tongue volume. A further study needs to be performed in the patients with snoring and OSA.

• Culinary science and hospitality research
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• v.21 no.4
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• pp.284-293
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• 2015

This study was intended to investigate food, exercise habits, perception of health status and the effects of nutrient intake of female college students. Food habits such as regularity of meal time, repast of breakfast, numbers of night snack per week and duration of meal were assessed via a self reporting questionnaire, and 24hrs recall method for nutrient intake was obtained from 155 female college students in Yangju-si. The mean height and weight of the subjects were $161.25{\pm}3.52cm$ and $52.26{\pm}4.52kg$, respectively. The average intakes of energy and nutrients were below the Korea recommended dietary allowance(RDA). Especially, The nutrient intakes(energy, protein, fat, fiber, calcium, iron, phosphorus, zinc, sodium, potassium, vitamin B6, niacin, vitamin C, folate, vitamin E, cholesterol) of the group in which the regularity of meal time per week was 5~7 days was significantly higher than the group in which the regularity of meal time was < 3 days (p<0.005). The nutrient intakes influenced by the food habit such as the regularity of meal time, skipping breakfast, and the numbers of night snack per week but did not differ in accordance with the regular exercise habits and perception of health status. These findings suggest that nutritional education based on female college students' food habits(regularity of meal time, skipping breakfast and night snacks per week, and duration of meal) may be required to improve dietary variety. It is considered that the improvement in dietary habits will contribute to the improvement of nutrition.

• Sleep Medicine and Psychophysiology
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• v.8 no.2
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• pp.129-137
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• 2001

Objectives: The purpose of this study is to investigate the effects of 38-hour sleep deprivation on fine motor performance. The Motor Performance Series (MPS) in the Vienna Test System (computerized neurocognitive function tests) was used in this study. Methods: Twenty four subjects participated in this study. Subjects had no past history of psychiatric disorders and physical illness. Subjects had normal sleep-waking cycle without current sleep disturbances and were all right-handed (Annett's Hand Preference Questionnaire: above +9 points). To minimize the learning effects, familiarization with the Vienna Test System was performed one day before the study. Subjects were to get up at 6:00 in the morning after getting enough sleep according to his or her usual sleep-wake cycle. After awakening, subjects remained awake for 38 hours under continuous surveillance. During two consecutive study days, the subjects tested MPS at 7 AM and 7 PM each day, which means the MPS was done four times in total. During the experiment, anything that could affect the subjects' sleep such as coffee, tea, alcohol, a nap, tiring sports, and all medications were prohibited. Results: In MPS, the fine motor functions of both hands decreased after 38 hours of sleep deprivation. The decrement in motor performance was prominent in the dominant right hand. In the right hand, the total number of tapping was reduced (p<.005), and the number of misses (p<.05) and the length of misses (p<.05) of line tracking, the total length of inserting a short pin (p<.01), the total length of inserting a long pin (p<.05), and the number of misses in aiming (p<.05) increased. Such performance decrement was distinct in the morning sessions. Conclusions: These results suggest that fine motor performance decrement during sleep deprivation is predominant in the right hand, which exerts maximal motor function. The finding of decrement in motor function in tapping during sleep deprivation also suggested that the time required for exhaustion of muscles is shortened during sleep deprivation. More deterioration of motor performance was shown in the morning, which could be explained as circadian rhythm effects.

• Tuberculosis and Respiratory Diseases
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• v.57 no.1
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• pp.19-24
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• 2004

Background : It is difficult to differentiate between tuberculous pneumonia and Community Acquired Pneumonia, so the diagnosis and treatment of tuberculous pneumonia can be delayed frequently. In this study, we attempted to retrospectively evaluate the clinical and radiologic characteristics of tuberculous pneumonia. Methods : We conducted a retrospective analysis of clinical characteristics of 58 patients diagnosed with tuberculous pneumonia from Nov. 1997 to May 2001 at Korea university kuro hospital. Result : The male to female ratio was 1:1 and the mean age at diagnosis was $54.5{\pm}18.6$ years. Fifty five patients were confirmed microbiologically and three patients pathologically. There were 20 patients(34.5%) who had diabetes mellitus(8cases), chronic obstructive pulmonary disease(3cases), malignancy(3cases), bronchiectasis(2cases), chronic renal failure(1cases) or long term history of corticosteroid treatment(3cases). Many patients had multilobar infiltration in chest X-ray, dominantly in the lower lobe. thirty two patients(55.2%) had infiltration in more than 2 lobes and 5 patients in more than 4 lobes. The significant correlation between the diabetes mellitus and the infiltrated Rt lower lobe(RLL) was found on the borders of confidence limit.(P=0.07<0.1). There was significant correlation between woman and infiltrated lobe(RML, RLL, LLL) excluding the both upper lobe(P=0.029). Conclusion : We must consider tuberculous pneumonia when lobar pneumonia with consolidation resistant to antibiotics, especially in the patients who have diabetes mellitus, chronic obstructive pulmonary disease, malignancy, bronchiectsis, chronic renal failure or long term history of corticosteroid treatment.