• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.228-235
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• 2004

The development and proliferation of the mandibular condyle can be altered by changes in the biomechanical environment of the temporomandibular joint. The biomechanical loads were varied by feeding diets of different consistencies. The purpose of the present study was to determine whether changes of masticatory forces by feeding a soft diet can alter the trabecular bone morphology of the growing mouse mandibular condyle, by means of micro-computed tomography. Thirty-six female, 21 days old, C57BL/6 mice were randomly divided into two groups. Mice in the hard-diet control group were fed standard hard rodent pellets for 8 weeks. The soft-diet group mice were given soft ground diets for 8 weeks and their lower incisors were shortened by cutting with a wire cutter twice a week to reduce incision. After 8 weeks all animals were killed after they were weighed. Following sacrifice, the right mandibular condyle was removed. High spatial resolution tomography was done with a Skyscan Micro-CT 1072. Cross-sections were scanned and three-dimensional images were reconstructed from 2D sections. Morphometric and nonmetric parameters such as bone volume(BV), bone surface(BS), total volume(TV), bone volume fraction(BV/TV), surface to volume ratio(BS/BV), trabecular thickness(Tb. Th.), structure model index(SMI) and degree of anisotropy(DA) were directly determined by means of the software package at the micro-CT system. From directly determined indices the trabecular number(Tb. N.) and trabecular separation(Tb. Sp.) were calculated according to parallel plate model of Parfitt et al.. After micro-tomographic imaging, the samples were decalcified, dehydrated, embedded and sectioned for histological observation. The results were as follow: 1. The bone volume fraction, trabecular thickness(Tb. Th.) and trabecular number(Tb. N.) were significantly decreased in the soft-diet group compared with that of the control group (p<0.05). 2. The trabecular separation(Tb. Sp.) was significantly increased in the soft-diet group(p<0.05). 3. There was no significant differences in the surface to volume ratio(BS/BV), structure model index(SMI) and degree of anisotropy(DA) between the soft-diet group and hard-diet control group (p>0.05). 4. Histological sections showed that the thickness of the proliferative layer and total cartilage thickness were significantly reduced in the soft-diet group.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.1
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• pp.73-82
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• 2009

Injectable calcium phosphate cement (CPC) has been used as bone substitute successfully due to good biocompatibility and osteoconductivity. One of the important mechanical characteristics of CPC is flowablility, which can be evaluated by measuring rheological parameters. However, there have been few studies that measured rheological properties of CPC. The purpose of this study was to evaluate the effects of temperature and concentrations of 2 kinds of setting solutions, hydroxyprophyl methylcellulose (HPMC) and polyacrylic acid (PAA), on rheological properties of CPC. The CPC used was dicalcium phosphate dihydrate (DCPD). Rheological properties of CPC paste were measured using rheometer. The effect of concentrations of each solution (2% and 1% HPMC and 35% and 17.5% PAA) was evaluated. The effect of temperature ($25^{\circ}C$ and $37^{\circ}C$) on the rheological properties of CPC was also investigated. The statistical analysis was carried out with Mann-whitney test with Bonferronis collection. CPC with both setting solutions showed shear thinning behavior. Higher concentrations of setting solution (2% HPMC and 35% PAA) produced significantly higher viscosity than lower concentrations of setting solution (1% HPMC and 17.5% PAA). CPC with HPMC showed significantly higher viscosity at $37^{\circ}C$ that at $25^{\circ}C$. CPC with PAA showed lower viscosity at $37^{\circ}C$ than at $25^{\circ}C$, although the difference was not statistically significant. The results showed that CPC with HPMC or PAA solutions are pseudoplastic and the concentrations of setting solutions and temperature may have an effect on the rheological properties of CPC paste. These results showed that the flowability of injectable CPC could be improved by use of increasing frequency of oscillation. In clinical practice, the use of ultrasonic vibration would be helpful in application of injectable CPC. CPC with HPMC could be more easily applicated at $25^{\circ}C$ than $37^{\circ}C$. The use of lower concentrations of HPMC and PAA solution would be beneficial in terms of flowability.

• Tuberculosis and Respiratory Diseases
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• v.46 no.1
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• pp.36-43
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• 1999

Background : Tumor growth is the net result of intrinsic proliferation and escape from active cell death. bcl-2 is a member of a new category of oncogenes that is not involved in influencing cell proliferation but is involved in regulating cell death(apoptosis). Based on this information, it seems to be reasonable to expect that there may be clinical prognostic significance of bcl-2 expression in non-small cell lung cancer. But its prognostic significance is not established. Methods: To investigate the role of bcl-2 in lung cancer, we performed immunohistochemical stain of bcl-2 on 57 biopsy specimens from resected primary non-small cell lung cancer. Thereafter, flow cytometric cell cycle analysis was done. And we analyzed the correlation between bcl-2 expression, clinical parameters, S-, $G_1$-phase fraction and survival. Results: bcl-2 were detected in 43.8% of total 57 patients(according to histology, squamous cancer 47%, adenocarcinoma 32%, according to TNM stage, I 28.6%, II 52.3%, III 45.5%. both differences were insignificant). By using the flow cytometric analysis, mean S-phase fraction of bcl-2(+) and (-) group were 14.1($\pm7.8$)%, 24.7($\pm10.5$)% (p<0.005), mean $G_1$-phase fraction of bcl-2(+) and bcl-2(-) group were 75.5($\pm10.8$)%, 65.5($\pm11.4$)%(p<0.05). 2yr, 3yr and 5yr survival and median survival time of bcl-2(+) group were 65%, 54%, 41%, 53 months, and those of bcl-2(-) group were 71%, 52%, 46%, 37 months. (p>0.05, Kaplan-Meier, log rank) Conclusion: bcl-2 was detected in 43.8% of primary non-small cell lung cancer. The S-phase fraction of bcl-2(+) group was less than bcl-2(-) group, and G1-phase fraction of bcl-2(+) group was more than bcl-2(-) group. But, expression of bcl-2 could not be a prognostic factor.

• Korean Chemical Engineering Research
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• v.40 no.6
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• pp.746-751
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• 2002

Fluidized bed combustion is a coal combustion technology that can reduce both SOx and NOx emission; SOx is removed by limestone that is fed into the combustion chamber and the NOx is reduced by low temperature combustion in a fluidized bed combustor and air stepping, but $N_2O$ generation is quite high. $N_2O$ is not only a greenhouse gas but also an agent of ozone destruction in the stratosphere. The calcium oxide(CaO) is known to be a catalyst of $N_2O$ decomposition. This study of $N_2O$ decomposition reaction in fixed bed reactor packed over CaO bed has been conducted. Effects of parameters such as concentration of inlet $N_2O$ gas, reaction temperature, CaO bed height and effect of $CO_2$, NO, $O_2$ gas on the decomposition reaction have been investigated. As a result of the experiment, it has been shown that $N_2O$ decomposition reaction increased with the increasing fixed bed temperature. While conversion of the reaction was decreased with increasing $CO_2$ concentration. Also, under the present of NO, the conversion of $N_2O$ decomposition is decreased. From the result of kinetic study gained the heterogeneous reaction rate on $N_2O$ decomposition. In the case of $N_2O$ decomposition over CaO, heterogeneous reaction rate is. $\frac{d[N_2O]}{dt}=\frac{3.86{\times}10^9{\exp}(-15841/R)K_{N_2O}[N_2O]}{(1+K_{N_2O}[N_2O]+K_{CO_2}[CO_2])}$. In this study, it is found that the calcium oxide is a good catalyst of $N_2O$ decomposition.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.1
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• pp.72-79
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• 2008

This study investigated the changes in textural characteristics that occurred by adding maltose syrup, dextrin, and sucrose to whole egg gels, by assessing coagulation after cooling. It also examined the optimal NaCl and sucrose concentrations for whole egg gels sensory evaluations, and then studied how the addition of sucrose effected gel formation and textural characteristics under optimal NaCl concentration. The additions of maltose syrup, dextrin, and sucrose, presented some color changes. The greater the addition of maltose syrup or dextrin, the lower the L, a, and b values of the whole egg gel and whole egg liquid, and ultimately the color turned dark bluish green. With increasing additions of sucrose, maltose syrup, and dextrin, the viscosity of the whole egg liquid increased slightly. In terms of the mechanical texture characteristic of the gel, the texture was most elastic with the 0.8% addition of sucrose, and hardness decreased by increasing the ratio of added sucrose. Increasing amounts of maltose syrup resulted in less hardness and SF. And for dextrin, the SF increased up to 2.5 and then decreased, and hardness decreased with increasing amounts of dextrin. Based on sensory evaluations, the 0.8% addition of NaCl was significantly preferred(p<0.05), in terms of salty taste. The overall preference scores indicated that the whole egg gel made with 0.3% sucrose and the optimal NaCl concentration(0.8%) was most preferred, and each sample was significant(p<0.05). Under the optimal 0.8% NaCl concentration increasing the sucrose concentration resulted in a darker egg gel color, in terms the L value. SF, NF, and hardness, which are mechanical texture parameters, were when 0.8% sucrose and the optimal NaCl concentration of 0.8% were added to whole egg liquid, in preparing the whole egg gel.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.3
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• pp.345-352
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• 2011

TMR feed was developed by adding mugwort (Artemisia capillaris), and was fed to Hanwoo cattle to investigate the effects of feeding mugwort on the physicochemical and sensory characteristics of rump meat, and to determine the feasibility of producing Hanwoo beef with high quality and functionality. The experimental samples consisted of the Hanwoo rump from cattle fed with fattening TMR feed without mugwort (T0), and those fed with fattening cattle TMR feed supplemented with mugwort (T1). T1 was significantly higher than T0 for Hanwoo rump characteristics of Hunter's $L^*$, $a^*$, $b^*$ values (p<0.05). VBN content for T0 was significantly higher than for T1, and EDA for T1 was significantly higher than for T0 (p<0.05). There was no significant difference between T0 and T1 in terms of pH, TBARS, and total bacterial numbers. Water holding capacity for T1 was significantly higher than for T0 (p<0.05), but there was no significant difference between T0 and T1 in terms of freezing loss, thawing loss, and cooking loss. Springiness for T1 was significantly higher than for T0 (p<0.05), and there was no significant difference between T0 and T1 in terms of hardness, cohesiveness, gumminess, chewiness, and shear force. There was no significant difference between T0 and T1 in terms of acid value, peroxide value, and iodine value. However, the melting point for T1 was significantly lower than for T0 (p<0.05). Aroma of raw meat for T1 was significantly superior to aroma for T0 (p<0.05). Taste, palatability of boiled meat, and juiciness of roasted meat for T1 were significantly superior to those parameters for T0 (p<0.05). These results suggest that the feed containing mugwort can be used to improve color and sensory characteristics, inhibit VBN formation, and also to increase antioxidant ability as a functional feed.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.253-261
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• 2016

Egg quality is a very important factor for both consumers and producers. Factors affecting egg quality include strain and age of hens; egg storage temperature, time, and humidity; laying season; and feeding. This study aimed to determine the effect of hen age and egg storage time on egg quality. A total of 700 eggs obtained from Hyline Brown commercial layers were used for this experiment, and they were separated into two hen age groups (30 vs. 60 weeks) with eight treatments and four storage times (day 0, 10, 20, and 30). The egg weight; shell color, thickness, and density; albumen height; Haugh unit (HU); yolk color; and the yolk and albumen pH and viscosity were measured for the egg quality assessment. The results showed that the age of the hen and egg storage time significantly affected almost all parameters of the internal and external egg quality. The shell thickness, albumen height, HU, yolk color, pH of yolk and albumen, and yolk viscosity significantly decreased with increasing hen age. The egg shell color was significantly lighter in eggs from 60-week-old hens than in those from 30 weeks-old hens. The egg weight; shell weight, thickness, and density; albumen height, HU; and albumen viscosity significantly decreased, but the yolk color and pH of the yolk and albumen increased with increasing egg storage time. The interaction effects between the storage time and hen age were significant in shell thickness, albumen height, yolk color, and yolk and albumen pH and viscosity. The eggs obtained from 60-week-old hens showed significantly lower shell thickness, albumen height, and HU values, which are considered typical egg quality measurements, than values of eggs from 30-week-old hens. Therefore, increasing hen age and egg storage time caused the deterioration of egg quality. In conclusion, this study demonstrated that hen age is the major factor affecting the quality of fresh eggs, whereas the storage time is the determinant factor affecting the quality of stored eggs.

• Journal of Chest Surgery
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• v.36 no.11
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• pp.799-811
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• 2003

Background: The aim of this study is to define the cardioprotective effects (hemodynamic, cytochemical and ultrastructural of the newly developed Histidine-Tryptophan-Ketoglutarate (HTK) cardioplegia compared to DelNido cardioplegia. Material and Method: Seventy-nine isolated rat hearts were divided into three groups on the basis of techniques of cardioplegia infusion. Twenty-eight hearts (Group 1) were flushed with cold DelNido cardioplegia with every 40 minutes for 2 hours. Twenty-seven hearts (Group 2) were flushed with cold HTK cardioplegia for once during the 2 hours. Twenty-four hearts (Group 3) were flushed with cold HTK cardioplegia with every 40 minutes for 2 hours. Heart rate, left ventricular developed pressure (LVDP), changes of + dp/dt max, coronary flow, and rate-pressure product value were measured at pre-ischemic, post-reperfusion 15 minutes, 30 minutes, and 45 minutes for hemodynamic study. Aspartate aminotransferase (AST), lactate dehydrogenase (LD), creatine kinase (CK), CK-MB, troponin-I, myoglobin, and lactate were measured at pre-ischemic and post-reperfusion 45 minutes for cytochemical parameters. Mitochondrial scores were counted in 3 cases from each group for ultrastructural assessment. Result: In hemodynamic study, there were no significant differences among group 1, group 2, and group 3. However, the decrease values of heart rate in group 2 and 3 exhibited significantly lower values than in group 1. In cytochemical study, there were no significant differences among group 1, group 2, and group 3. However, the increase values of lactate in group 2 and 3 exhibited significantly lower values than in group 1. In ultrastructural assessment, the mean myocardial mitochondria scores in group 1, group 2, and group 3 were 2.14$\pm$0.10, 1.52$\pm$0.57, and 2.10$\pm$0.16. Conclusion: HTK solution provides adequate myocardial protection with some advantages over DelNido solution in isolated rat hearts.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.101-107
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• 1985

Since most farmers breeding livestocks in Korea is depended on imported feeds, the rate of self-supplying feeds is very important for a stable development of farmers. Therefore, it is considered necessary to increase the rate of self-supplying feeds. In this study, performance tests were carried out with barley and forage to find the design's parameters of hammer for a small size hammer mill which can be driven by 3.7-7.5 kW power tiller being used by most farmers. The revolution speed of hammer mill was 3000 rpm, widths of hammer were 20mm, 30mm, 40mm, and the levels of thickness of hammer were 2mm, 4mm and 6mm. Experimental materials used were barley and forage and screen openings for barley was 4.76mm, and 3.18mm for forage. The study results can be summarized as follows; 1. Results of grinding tests showed that particle sizes were 478-774 microns for barley and 350-434 microns for forage. They were decreased according to the increasing thickness and width of hammer. 2. Fineness modulus of grinded materials were 3.07-3.62 for barley and 2.69-2.93 for forage. They were inversely proportional to thickness and width of hammer. 3. The required power for grinding was 3.8-5.0 kW for barley and 0.9-1.4 kW for forage. The thickness of hammer was more important for less power requirement than width of hammer. 4. Grinding performance of a small size hammer mill was 99-170kg/kWh for barley and 11-21 kg/kWh for forage. The thickness of hammer was an important factor for grinding performance, and inversely proportional to grinding performance. For about 3.2 of fineness modulus, 4 mm thickness was the best, and an optimum width of hammer was 30mm for a small size hammer mill.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.522-532
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• 2010

The aims of the present study were to characterize the effect of glucocorticosteroids (GCs) on the normal canine skin and to evaluate the effect of a lipid mixture (LM), containing cholesterol, pseudoceramide, and free fatty acid, on the steroid-induced damaged skin of dogs. Five beagles were involved and the skin of the back of each dog was topically applied with four kinds of GCs twice daily for 28 days. LM was applied after that period of GCs application. Transepidermal water loss (TEWL), skin hydration, and skin pH were assessed during experimental periods and histopathological evaluation was performed. TEWL was significantly increased, with a maximum increase obtained on day 28 (p < 0.01). Skin pH was significantly decreased, with a maximum decrease obtained on day 28 (p < 0.01). Skin surface hydration was significantly increased on day 3, but values of skin hydration were progressively decreased and finally reached those of baseline. In histology, as results of steroid application, losses of keratin layers in the stratum corneum and edematous changes in the upper parts of dermis, and consequently, thickness of the epidermis and the stratum corneum were decreased. In addition, the numbers of hair follicles were markedly decreased in steroid control as compared to intact control. However, these skin atrophic changes were markedly inhibited by treatment of LM as compared with steroid control in the present study. Moreover, all biophysical parameters were reached to the baseline after LM treatment. These results showed that the topically applied GCs induced skin barrier impairment and a LM should be effective on repair of disturbed skin barrier function in dogs. Therefore, it is concluded that a LM tested in the present study is expected to treat the steroid-induced skin damages.