• Title/Summary/Keyword: difference in difference(DID)

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A STUDY ON THE PHYSICAL PROPERTIES OF RESTORATIVE MATERIALS FOR PHOTO-POLYMERIZATION OF ARGON LASER (아르곤 레이저를 이용한 광중합 수복재의 물리적 성질에 관한 연구)

  • Ju, Sang-Ho;Choi, Hyung-Jun;Kim, Seong-Oh;Lee, Jong-Gap
    • Journal of the korean academy of Pediatric Dentistry
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    • v.25 no.2
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    • pp.368-382
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    • 1998
  • The purpose of this study is to evaluate and compare the results of argon laser for 5 seconds, argon laser for 10 seconds, and visible light for 40 seconds photo-polymerization in compressive strength, microhardness, curing depth, temperature rising during polymerization, and polymerization shrinkage. Hybrid type composite resin(Z-100) and compomer(Dyract) were used to be compared. The compressive strength was measured by an Instron(1mm/min cross head speed) in 60 specimens and the microhardness of the surface was expressed by Vickers Hardness Number(VHN) in 30 specimens. The curing depth was evaluated comparing the different values of upper and lower VHN according to irradiation time and thickness for the light source polymerization in 60 specimens. The temperature rising during photopolymerization was observed by the temperature change with thermocouple sensitizer beneath 40 specimens at the argon laser for 10 seconds and visible light 40 seconds irradiation. The polymerization shinkage was evaluated by calculating the decrease of % volume by using a dilatometer in 30 specimens. The results were as follows ; 1. In the case of compressive strength, the argon laser polymerization groups were higher than visible light group in Z-100 (p<0.05). In Dyract, the argon laser 5 seconds group did not show a significant difference with the visible light 40 seconds group. The argon laser 10 seconds group showed the markedly low value when compared with other groups (p<0.05) 2. In microhardness, Z-100 was better than Dyract when comparing by VHNs (p<0.05); however, there was not a significant difference between two materials in the visible light 40 seconds group and the argon laser 10 seconds group. 3. In the study of curing depth, Z-100 showed the consistent polymerization in argon laser irradiation because there was no difference in the VHN decrease according to the thickness change. Over the thickness control, the results did not show a significant difference between visible light and argon laser group in Z-100; however, in the case of Dyract, the visible light 40 seconds group was better than the argon laser groups(p<0.05). 4. There was a significant difference between the two materials in temperature rising during polymerization (p<0.05), but not a significant difference between irradiation times, 5. There was not a significant difference between the two materials in polymerization shrink age. The argon laser 5 seconds group was smaller than the other groups (p<0.05). It could be concluded that Z-100 polymerization was recommended to use the argon laser for reduction of the irradiation time while Dyract was recommended to use the visible light polymerization.

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Factor Affecting Mandibular Rotational Troque Movements (하악의 비틀림회전운동에 영향을 미치는 요인)

  • 이유미;한경수;허문일
    • Journal of Oral Medicine and Pain
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    • v.23 no.2
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    • pp.143-155
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    • 1998
  • This study was performed to investigate the factor that might affect mandibualr body rotation. For the study, 115 patients with temporomandibular disorders and 35 dental students without angy signs and symptoms of temporomandibular disorders were randomly selected as the patient group and the contreol group, respectively. Preferred chewing side, Angle' classification, lateral guidance pattern, and affected side were clinically recorded, and the amount of Mandibular body rotational torque movement was measured in wide opening and closure, in right and left excursion with vertical and lateral distance in frontal plane, right and left rotational angel in horizontal and in frontal plane. Masticatory muscle activity of anteriorocclusal contact pattern on maximal hard biting were also observed synchronously with BioEMG and T-Scan , respectively. The observed items were muscle activity of anterior temporalis and superficial masseter, and tooth contact status related to contact number, force, duration, and occlusal unbalance between right and left arch. The data collected were analyzed by SAS statistical program. The results of this study were as follows : 1. Mean value of vertical distance in frontal plane in wide opening and closure was more in control subjects than in patients, but there was no difference for rotational angle. In right excursion, rotational angles were greater in patient group than in control group. 2. Comparison among the subjects by preferred chewing side did not reveal any significant difference, but comparison among patients by affected side showed more rotational amount in bilaterally affected patients than in unilaterally affected patients. 3. Comparison among the subjects by Angle's classification or lateral guidance pattern revealed no difference. There was also no difference between preferred chewing side and contralateral side, and between affected side and contralateral side. 4. Positive correlation in madibular rotational torque movements were observed among vertical distance, total horizontal rotation angle, electromyographic activity of anterior temporalis, tooth contact number, and tooth contact force but total frontal rotation angle almost did not show any correlation with other variables except vertical distance.

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Quality Characteristics of Muffins Containing Purple Colored Sweetpotato Powder (자색 고구마가루 첨가량에 따른 머핀의 품질 특성)

  • Ko, Seong-Hye;Seo, Eun-Ok
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.2
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    • pp.272-278
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    • 2010
  • Various quality attributes were determined in muffins prepared using purple-colored sweet potato flour. Height of control muffins was 5.8 cm lease clarify. Height decreased with increasing quantity of sweet potato powder. Muffin volume was not appreciably affected. Moisture of control muffins was 21.84. The moisture value decreased with increasing quantity of sweet potato powder. Scanning electron microscopy examination revealed thick cell wall and rough stoma in muffins prepared with purple-colored sweet potato powder. The amount of gluten decreased as the quantity of purple-colored sweet potato powder increased. Brightness L values significantly changed as the amount of powder increased, indicative of a progressively darker product. Red index a values decreased as the quantity of purple-colored sweet potato powder increased. Yellow index b values decreased significantly in the control group as powder quantity increased. Hardness increased with increasing addition of powder, but no significant difference was evident between 6% and 9% amended samples. There were also no significant differences in springing in samples containing 3% and 6% powder but 9% powder produced a significant difference. Cohesiveness did not differ in unamended samples and samples amended with 3% and 9% powder, however a significant difference was evident in samples prepared with 6% powder. Gumminess and chewiness increased as the quantity of purple-colored sweet potato powder increased. Color did not differ appreciably in sample prepared with 3% and 9% Sample prepared with 3% additives showed the highest What? Color score? Something else? Please clarify with 6.4. There was no significant difference of the flavor in samples prepared with 3% and 6% powder, or in taste among samples prepared 3%, 6%, and 9% powder. No significant differences in texture were evident in any sample Overall acceptability was highest (7.2) in samples prepared with 3% of purple-colored sweet potato.

Quality Characteristics of Muffins Containing Domestic Blueberry (V. corymbosum) (국내산 블루베리 첨가 머핀의 품질 특성)

  • Hwang, Seung-Hwan;Ko, Seong-Hye
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.5
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    • pp.727-734
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    • 2010
  • As the blueberry content in batter increased, the pH of batter decreased According to the measured results about specific gravity of muffin batter, there was no significant difference among each batter including 0% 10% and 15% blueberry, while each 15% 20% and 30% dough showed significant difference (p<0.001). According to the results about general quality characteristics of muffins such as volume, weight and specific gravity, as the content of blueberry juice increased, the volume decreased. In terms of measuring specific volume, it decreased as the added amount increased According to measuring the chromaticity of muffins, as the blueberry content increased in the muffins, brightness and yellowness decreased while redness increased In terms of the measurement of texture, the hardness showed significant difference among all sample muffins (p<0.001). Significant difference was not shown in the springiness (p<0.05). As the amount of blueberry juice increased, the chewiness of the muffins was grown. The result showed a significant difference between samples in the adhesiveness (p<0.001). As the amount of blueberry juice increased, the adhesiveness of muffins also increased In the organoleptic test, a significant difference was shown in the color among all sample (p<0.001). The blueberry juice content of 20% showed highest figures with $7.12{\pm}0.67$. In terms of flavor, the content of 20% also showed highest figures among all samples with $7.16{\pm}0.62$ (p<0.001). Concerning the taste all samples showed a significant difference while 20% content did the highest figure. In the overall acceptability the content of 10% showed the lowest figure while 20% displayed the highest figure with 7.16. According to the quality characteristics of blueberry muffins, the best blueberry juice content would be 20% content group.

A Study of the Fluid Balance of the Patients on Soft Diets (유동식을 섭취하는 대상자의 수분 섭취와 배설의 균형 분석)

  • 양영희;최스미;김은경;성일순
    • Journal of Korean Academy of Nursing
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    • v.26 no.3
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    • pp.688-696
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    • 1996
  • The purpose of this study was to investigate the fluid balance of the patients who were either on soft fluid diet or total parenteral nutrition. We studied 19 patients with neurologic disorders and 22 patients with oromaxillary surgery who were admitted to either D university hospital in Choognam or S general hospital in Seoul between May and November 1995. The mean age for the patients who had oromaxillary surgery was 24 years and their average hospital stay was 9 days. The mean age of the patients with neurologic disorders was 54 years and they were bedridden for average of 71 days. For the maxillary bone surgery patients we did not limit the range of their activities in the ward during data collection period. The patients with neurological disorders were bedridden and did not move around the ward. They were all either on soft fluid diet, or total parenteral nutrition. The findings of this study are as follows ; 1) The difference of the triceps skinfold thickness between the baseline and the final measurement was 0.4cm for neurologic patient group and 0.5cm for oromaxillary surgery patient group. The difference was not statistically significant in each group. 2) In the oromaxillary surgery patient group, the daily intake of fluid in the form of pure water, other beverages, fluid diet as well as IV fluid was 4581m1 while urine output was 2979ml. The difference between fluid intake and output was statistically significant, indicating that fluid intake was far more than urine output. In neurologic patient group, the daily intake of fluid including water from fluid diet and IV fluid was 2701m1 whereas urine output was 2253m1 and they were statistically significant. 3) For a more accurate assessment we adjusted the fluid balance based on weight changes during data collection period. In the oromaxillary surgery patient group. the difference between fluid intake and output was 1238m1 after weight changes being adjusted. The difference was statistically significant, suggesting fluid overload in this patient group. In neurologic patient group, the difference between fluid intake and output considering weight changes was 124ml. The difference was not statistically significant, suggesting that the fluid intake and output was well balanced in this patient group.

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Enzymatic Processing and Property of Denim by Acid Cellulase (산성 셀룰라제 이용한 데님의 효소가공 및 물성)

  • Seo, Hye-Young;Song, Wha-Soon;Kim, Hye-Rim
    • Fashion & Textile Research Journal
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    • v.11 no.3
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    • pp.465-468
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    • 2009
  • In this study, acid cellulase was used to treat denim fabrics by varying pH, temperature, enzyme concentration, treatment time and non-ionic surfactant (Triton X-100) concentration. Treatment condition was controlled based on the weight loss. The characteristics of enzyme-treated fabrics were measured in terms of tearing strength, stiffness, and color difference. The optimum conditions for cellulase treatment of denim fabric were pH 5.0, $50^{\circ}C$, 3% (o.w.f.), 90minutes. The weight loss did not change significantly with the addition of a non-ionic surfactant, but it improved when more non-ionic surfactant were used. The tearing strength of enzyme-treated denim fabrics did not deteriorate. The stiffness of the treated fabrics improved with the enzymatic treatment with and without the non-ionic surfactant. The difference in color of fabrics treated with enzyme increased.

A Study on the Influences of Stressful Events and Coping Behavior on Mental Health (스트레스 사건과 적응행동이 정신건강에 미치는 경향에 대한 연구)

  • 이평숙;임현빈
    • Journal of Korean Academy of Nursing
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    • v.10 no.1
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    • pp.57-64
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    • 1980
  • The purpose of the study was to find out the relationship between experienced stressful events and its coping behavior within mentally wellness and illness, and to define the effective coping method under the stressful situation. By doing so, during the period of April, 1978- to March, 1979 the objects of this study were 100 persons who were under the psychiatric facilities in their first hospitalization, and who were registered in psychiatric out patient department in the form general hospitals located at Seoul selected as a experimental group. As a control group 100 persons who never experienced psychiatric treatment who were not under the current medical treatment, and who were tarring appropriate social roles in their community were selected, and in both groups utilized questimaires for Social Readjustment Pating Scale and Coping Scale. This study was tested by X$^2$ examinationand by F-ratio(analysis of variance). Results were as follows : Hypothesis 1. The actually experienced life events were expected to be higher in the experimental group than in the control group, but they did not show the significant difference between the groups.( p >0.05) Thus hypothesis 1 was rejected. Hypothesis : 2. The stress scores were expected to be higher in the experimental group than in the control group, and also did show the significant difference between the groups ( p< 0.05). Therefore hypothesis 2 was supported. Hypothesis 3. The non-effective coping behavior were expected to be higher in the experimental group than in the control group, and also did show the significant difference between the two groups(p < 0.001). Also hypothesis 3 was supported. Hypothesis 4 . The higher stress score groups (above 250 LCU ) were expected to utilize non.effective coping method more frequently than in the lower stress score groups (below 249 LCU ), and not only they showed high in utilizing non-effective coping method but also showed high in utililzing effective coping method. Thus hyphothesis 4 was partially supported. (p < 0.001) The following are drawn out based on the result of this study that the stress scores were higher, and more utilized non-effective coping method in the emotionally disturbances than in the emtionally healthies.

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Masking Level Difference: Performance of School Children Aged 7-12 Years

  • de Carvalho, Nadia Giulian;do Amaral, Maria Isabel Ramos;de Barros, Vinicius Zuffo;dos Santos, Maria Francisca Colella
    • Journal of Audiology & Otology
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    • v.25 no.2
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    • pp.65-71
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    • 2021
  • Background and Objectives: In masking level difference (MLD), the masked detection threshold for a signal is determined as a function of the relative interaural differences between the signal and the masker. Study 1 analyzed the results of school-aged children with good school performance in the MLD test, and study 2 compared their results with those of a group of children with poor academic performance. Subjects and Methods: Study 1 was conducted with 47 school-aged children with good academic performance (GI) and study 2 was carried out with 32 school-aged children with poor academic performance (GII). The inclusion criteria adopted for both studies were hearing thresholds within normal limits in basic audiological evaluation. Study 1 also considered normal performance in the central auditory processing test battery and absence of auditory complaints and/or of attention, language or speech issues. The MLD test was administered with a pure pulsatile tone of 500 Hz, in a binaural mode and intensity of 50 dBSL, using a CD player and audiometer. Results: In study 1, no significant correlation was observed, considering the influence of the variables age and sex in relation to the results obtained in homophase (SoNo), antiphase (SπNo) and MLD threshold conditions. The final mean MLD threshold was 13.66 dB. In study 2, the variables did not influence the test performance either. There was a significant difference between test results in SπNo conditions of the two groups, while no differences were found both in SoNo conditions and the final result of MLD. Conclusions: In study 1, the cut-off criterion of school-aged children in the MLD test was 9.3 dB. The variables (sex and age) did not interfere with the MLD results. In study 2, school performance did not differ in the MLD results. GII group showed inferior results than GI group, only in SπNo condition.

Masking Level Difference: Performance of School Children Aged 7-12 Years

  • de Carvalho, Nadia Giulian;do Amaral, Maria Isabel Ramos;de Barros, Vinicius Zuffo;dos Santos, Maria Francisca Colella
    • Korean Journal of Audiology
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    • v.25 no.2
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    • pp.65-71
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    • 2021
  • Background and Objectives: In masking level difference (MLD), the masked detection threshold for a signal is determined as a function of the relative interaural differences between the signal and the masker. Study 1 analyzed the results of school-aged children with good school performance in the MLD test, and study 2 compared their results with those of a group of children with poor academic performance. Subjects and Methods: Study 1 was conducted with 47 school-aged children with good academic performance (GI) and study 2 was carried out with 32 school-aged children with poor academic performance (GII). The inclusion criteria adopted for both studies were hearing thresholds within normal limits in basic audiological evaluation. Study 1 also considered normal performance in the central auditory processing test battery and absence of auditory complaints and/or of attention, language or speech issues. The MLD test was administered with a pure pulsatile tone of 500 Hz, in a binaural mode and intensity of 50 dBSL, using a CD player and audiometer. Results: In study 1, no significant correlation was observed, considering the influence of the variables age and sex in relation to the results obtained in homophase (SoNo), antiphase (SπNo) and MLD threshold conditions. The final mean MLD threshold was 13.66 dB. In study 2, the variables did not influence the test performance either. There was a significant difference between test results in SπNo conditions of the two groups, while no differences were found both in SoNo conditions and the final result of MLD. Conclusions: In study 1, the cut-off criterion of school-aged children in the MLD test was 9.3 dB. The variables (sex and age) did not interfere with the MLD results. In study 2, school performance did not differ in the MLD results. GII group showed inferior results than GI group, only in SπNo condition.

The Influence on Ambulation of the Difference in Muscle Strength on Lower Extremity of Hemiplegic Patients (편마비 환자의 하지의 근력 차이가 보행에 미치는 영향)

  • Yoon, Jang-Soon
    • Journal of Korean Physical Therapy Science
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    • v.12 no.3
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    • pp.47-58
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    • 2005
  • The purpose of this study is to estimate how much the motility of affected and unaffected lower limb respectively would have effects on their ambulation through comparing the difference between their affected and unaffected lower limb and studying the correlation between such difference and their ambulation. In addition, the study also intends to find out remedial measures suitable for improving their ambulation with relevant physical treatment. To do this, a quantitative electromyogram(QEMG) test was done to both quadriceps and hamstring of affected and unaffected lower limb so as to yield IP values. Based on such IP values, RMS(root mean square) values as the total sum of IP values were found with QEMG analysis system (made by Medelec Co.) and then the ambulation depending on the difference in muscular strength were analyzed by ink-foot print method as well as the corresponding statistics were processed by T-test through SPSS. The effect of differences in muscular strength of quadriceps in affected and unaffected limb of hemiplegic patients on their ambulation was also different in each element of ambulation. However, there was not any statistically significant difference (p>.05). The differences in muscular strength of hamstring in unaffected limbs of hemiplegic patients only affect stride length. It was statistically significant. The effect of difference in muscular strength of the hamstring in affected limb of hemiplegic patients on their ambulation was very different between strong and weak group in terms of walking velocity, step per minute, stride and step length, showing statistically significant difference(p<.05). Although there was a difference in the step length of the affected limb, it was not statistically significant(p>.05). For the unaffected hamstring, there were significant differences of stride length between in unaffected limb and in affected limb. For the affected hamstring, there were also significant differences in walking velocity, step per minute, stride and step length. Besides, it was found that the difference of the muscular strength between strong and weak group was at the highest. Thus, the effect of difference in muscular strength on ambulatory factors such as walking velocity, step per minute, stride and step length did not show any statistical significance but differences in affected and unaffected quadriceps. However, it was found that both the difference of stride in unaffected hamstring and the difference of all ambulatory factors except from step length with affected limb had effects on ambulation depending upon muscular strength.

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