• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.912-920
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• 2015

The study was designed to investigate the effects of die temperature and $CO_2$ injection on the physical and antioxidant properties of extruded rice with tomato flour. Moisture content and screw speed were fixed at 25% and 150 rpm, respectively. Die temperatures and $CO_2$ injection were adjusted to 80, 110, and $140^{\circ}C$ and 0, and 300 mL/min, respectively. Specific mechanical energy input decreased as die temperature increased from 80 to $140^{\circ}C$. The expansion index increased, while bulk density decreased with $CO_2$ injection. All extrudates showed increased water soluble index (WSI) and water absorption index through the extrusion process. WSI increased as die temperature increased. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and total phenolic compounds increased as die temperature increased from 80 to $140^{\circ}C$. Total carotenoid and lycopene contents decreased through the extrusion process. Total carotenoid and lycopene contents upon 0 mL/min $CO_2$ injection and $140^{\circ}C$ die temperature were highest at $6.65{\mu}g/g$ and 2.69 mg/kg, respectively. In conclusion, $CO_2$ injection affects expansion properties while an increased die temperature leads to increased DPPH radical scavenging activity and total phenols.

• Journal of agriculture & life science
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• v.45 no.1
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• pp.101-107
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• 2011

A Total of 48,101 performance records of sows for Yorkshire and Landrace breeds were collected from swine breeding farms in Korea from 2001 to 2008. A general ingredient analysis included the fixed effects of breed, parity, year, season, and farm. For the number of heads per 1st parity analysis by each growth traits, the data of 48,101 heads was used to analyze growth traits group. In the general ingredient analysis, the results showed high significance except for lean percentage by season (p<0.05). Average daily gain of Landrace breed ($640.48{\pm}0.749g$) was better than that of Yorkshire breed ($624.22{\pm}0.608g$), and the backfat thickness of Yorkshire breed ($13.44{\pm}0.030mm$) was thicker than that of Landrace breed ($12.50{\pm}0.037mm$). For the number of born alive and number of stillborn by growth traits for each breed, number of born decreased after test end day of 161 to 165 day, and average daily gain of 620 g to 640 g and the highest number of born appeared at the backfat thickness of 13 mm to 14 mm for yorkshire breed. In case of Landrace breed, number of born was the highest, and the number of stillborn increased together with average daily gain. The number of born was high when backfat thickness was less than 11 mm. The number of born trended to decrease when backfat thickness increased.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.473-481
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• 2023

Pinus densiflora is a fixed-growth coniferous species that elongates its shoot once a year and finishes growing in early summer. However, it may produce additional shoots in the same year in response to external stimuli, called abnormal shoot growth. This study investigated the effects of open-field summer warming and drought on the abnormal shoot growth of P. densiflora seedlings. In March 2022, two factorial combinations were constructed, including two temperature treatments (control and 4℃ increase) and two precipitation treatments (control and drought), with five replicates for each combination. The temperature treatment was performed for 87 days from May 14 to August 8, 2022, and the precipitation treatment was performed for 33 days from May 14 to June 15, blocking 100% of the ambient rainfall. The abnormal shoot occurrence rate and leaf unfolding stages were measured in November, and the shoot and root collar diameter growth rates were calculated by comparing the seedling height and root collar diameter measured in August(after the cessation of treatment) and October(after the end of growing period) with the initial values (i.e., May 2022). The abnormal shoot occurrence rate significantly increased under the warming treatment, showing a 410.6% increase in the warming plots (38.4%) compared to the control plots (7.5%). There was no significant difference in the shoot and root collar diameter growth rate regarding warming and drought treatments. Abnormal shoots may have been affected by high temperatures by inducing early transition to the next ontogenetic stage.

• Journal of Chest Surgery
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• v.37 no.2
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• pp.119-130
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• 2004

Decrease in cardiac function after open heart surgery is due to an ischemia induced myocardial damage during surgery, and ischemic preconditioning, a condition in which the myocardial damage does not accumulate after repeated episodes of ischemia but protects itself from damage after prolonged ischemia due to myocytes tolerating the ischemia, is known to diminish myocardial damage, which also helps the recovery of myocardium after reperfusion, and decreases incidences of arrythmia. Our study is performed to display the ischemic preconditioning and show the myocardial protective effect by applying cardioplegic solution to the heart removed from rat. Material and Method: Sprague-Dawley male rats were used, They were fixed on a modified isolated working heart model after cannulation. The reperfusion process was according to non-working and working heart methods and the working method was executed for 20 minutes in which the heart rate, aortic pressure, aortic flow and coronary flow were measured and recorded. The control group is the group which the extracted heart was fixed on the isolated working heart model, recovered by reperfusion 60 minutes after infusion and preserved in the cardioplegic solution 20 minutes after the working heart perfusion and aortic cross clamp, The thesis groups were divided into group I, which ischemic hearts that were hypoxia induced were perfused by cardioplegic solution and preserved for 60 minutes; group II, the cardioplegic solution was infused 45 seconds (II-1), 1 minutes (II-2), 3 minutes (II-3), after the ischemia induction, 20 minutes after working heart perfusion and aortic cross clamp; and group III, hearts were executed on working heart perfusion for 20 minutes and aortic cross clamp was performed for 45 seconds (III-1), 1minute (III-2), 3 minutes (III-3), reperfused for 2 minutes to recover the heart, and then aortic cross clamping was repeated for reperfusion, all the groups were compared based on hemodynamic performance after reperfusion of the heart after preservation for 60 minutes. Result: The recovery time until spontaneous heart beat was longer in groups I, II-3, III-2 and III-3 to control group (p<0.01). Group III-1 (p<0.05) had better results in terms of recovery in number of heart rates compared to control group, and recovered better compared to II-1 (p<0.05). The recovery of aortic blood pressure favored group III-1 (p<0.05) and had better outcomes compared with II-1 (p<0.01). Group III-1 also showed best results in terms of cardiac output (p<0.05) and group III-2 was better compared to II-2 (p<0.05). Group I (p<0.01) and II-3 (p<0.05) showed more cardiac edema than control group. Conclusion: When the effects of other organs are dismissed, protecting the heart by infusion of cardioplegic solution after enforcing ischemia for a short period of time before the onset of abnormal heart beats for preconditioning has a better recovery effect in the cardioplegic group with preconditioning compared to the cardioplegic solution itself. we believe that further study is needed to find a more effective method of preconditioning.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.207-221
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• 2012

Air temperature in Korea has increased by $1.5^{\circ}C$ over the last 100 years, which is nearly twice the global average rate during the same period. Moreover, it is projected that such change in temperature will continue in the 21st century. The objective of this study was to evaluate the potential impacts of future climate change on the rice production and adaptation methods in Korea. Climate data for the baseline (1971~2000) and the three future climate (2011~2040, 2041~2070, and 2071~2100) at fifty six sites in South Korea under IPCC SRES A1B scenario were used as the input to the rice crop model ORYZA2000. Six experimental schemes were carried out to evaluate the combined effects of climatic warming, $CO_2$ fertilization, and cropping season on rice production. We found that the average production in 2071~2100 would decrease by 23%, 27%, and 29% for early, middle, and middle-late rice maturing type, respectively, when cropping seasons were fixed. In contrast, predicted yield reduction was ~0%, 6%, and 7%, for early, middle, and middle-late rice maturing type, respectively, when cropping seasons were changed. Analysis of variation suggested that climatic warming, $CO_2$ fertilization, cropping season, and rice maturing type contributed 60, 10, 12, and 2% of rice yield, respectively. In addition, regression analysis suggested 14~46 and 53~86% of variations in rice yield were explained by grain number and filled grain ratio, respectively, when cropping season was fixed. On the other hand, 46~78 and 22~53% of variations were explained respectively with changing cropping season. It was projected that sterility caused by high temperature would have no effect on rice yield. As a result, rice yield reduction in the future climate in Korea would resulted from low filled grain ratio due to high growing temperature during grain-filling period because the $CO_2$ fertilization was insufficient to negate the negative effect of climatic warming. However, adjusting cropping seasons to future climate change may alleviate the rice production reduction by minimizing negative effect of climatic warming without altering positive effect of $CO_2$ fertilization, which improves weather condition during the grain-filling period.

• The Korean Journal of Physiology
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• v.1 no.1
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• pp.103-120
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• 1967

As pointed out by many previous investigators, the cardio-pulmonary system of well trained athletes is so adapted that they can perform a given physical exercise more efficiently as compared to non-trained persons. However, the time course of the development of these cardio-pulmonary adaptations has not been extensively studied in the past. Although the development of these training effects is undoubtedly related to the magnitude of an exercise load which is repeatedly given, it would be practical if one could maintain a good physical fitness with a minimal daily exercise. Hence, the present investigation was undertaken to study the time course of the development of cardio-pulmonary adaptations while a group of non-athletes was subjected to a daily 6 to 10 minutes running exercise for a period of 4 weeks. Six healthy male medical students (22 to 24 years old) were randomly selected as experimental subjects, and were equally divided into two groups (A and B). Both groups were subjected to the same daily running exercise (approximately 1,000 kg-m). 6 days a week for 4 weeks, but the rate of exercise was such that the group A ran on treadmill with 8.6% grade for 10 min daily at a speed of 127 m/min while the group B ran for 6 min at a speed of 200 m/min. In order to assess the effects of these physical trainings on the cardio-pulmonary system, the minute volume, the $O_2$ consumption, the $CO_2$ output and the heart rate were determined weekly while the subject was engaged in a given running exercise on treadmill (8.6% grade and 127 m/min) for a period of 5 min. In addition, the arterial blood pressure, the cardiac output, the acid-base state of arterial blood and the gas composition of arterial blood were also determined every other week in 4 subjects (2 from each group) while they were engaged in exercise on a bicycle ergometer at a rate of approximately 900 kg m/min until exhaustion. The maximal work capacity was also determined by asking the subject to engage in exercise on treadmill and ergometer until exhaustion. For the measurement of minute volume, the expired gas was collected in a Douglas bag. The $O_2$ consumption and the $CO_2$ output were subsequently computed by analysing the expired gas with a Scholander micro gas analyzer. The heart rate was calculated from the R-R interval of ECG tracings recorded by an Offner RS Dynograph. A 19 gauge Cournand needle was inserted into a brachial artery, through which arterial blood samples were taken. A Statham $P_{23}AA$ pressure transducer and a PR-7 Research Recorder were used for recording instantaneous arterial pressure. The cardiac output was measured by indicator (Cardiogreen) dilution method. The results may be summarized as follows: (1) The maximal running time on treadmill increased linearly during the 4 week training period at the end of which it increased by 2.8 to 4.6 times. In general, an increase in the maximal running time was greater when the speed was fixed at a level at which the subject was trained. The mammal exercise time on bicycle ergometer also increased linearly during the training period. (2) In carrying out a given running exercise on treadmill (8.6%grade, 127 m/min), the following changes in cardio·pulmonary functions were observed during the training period: (a) The minute volume as well as the $O_2$ consumption during steady state exercise tended to decrease progressively and showed significant reductions after 3 weeks of training. (b) The $CO_2$ production during steady state exercise showed a significant reduction within 1 week of training. (c) The heart rate during steady state exercise tended to decrease progressively and showed a significant reduction after 2 weeks of training. The reduction of heart rate following a given exercise tended to become faster by training and showed a significant change after 3 weeks. Although the resting heart rate also tended to decrease by training, no significant change was observed. (3) In rallying out a given exercise (900 kg-m/min) on a bicycle ergometer, the following change in cardio-vascular functions were observed during the training period: (3) The systolic blood pressure during steady state exercise was not affected while the diastolic blood Pressure was significantly lowered after 4 weeks of training. The resting diastolic pressure was also significantly lowered by the end of 4 weeks. (b) The cardiac output and the stroke volume during steady state exercise increased maximally within 2 weeks of training. However, the resting cardiac output was not altered while the resting stroke volume tended to increase somewhat by training. (c) The total peripheral resistance during steady state exercise was greatly lowered within 2 weeks of training. The mean circulation time during exorcise was also considerably shortened while the left heart work output during exercise increased significantly within 2 weeks. However, these functions_at rest were not altered by training. (d) Although both pH, $P_{co2}\;and\;(HCO_3-)$ of arterial plasma decreased during exercise, the magnitude of reductions became less by training. On the other hand, the $O_2$ content of arterial blood decreased during exercise before training while it tended to increase slightly after training. There was no significant alteration in these values at rest. These results indicate that cardio-pulmonary adaptations to physical training can be acquired by subjecting non-athletes to brief daily exercise routine for certain period of time. Although the time of appearance of various adaptive phenomena is not identical, it may be stated that one has to engage in daily exercise routine for at least 2 weeks for the development of significant adaptive changes.

• Journal of the Korean Society of Radiology
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• v.7 no.2
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• pp.113-120
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• 2013

Nowadays, the medical system towards patients changes into the medical services. As the human rights are improved and the capitalism is enlarged, the rights and needs of patients are gradually increasing. Also, based on this change, several systems in hospitals are revised according to the convenience and needs of patients. Thus, the cases of mobile portable among examinations are getting augmented. Because the number of mobile portable examinations in patient's room, intensive care unit, operating room and recovery room increases, neighboring patients are unnecessarily exposed to radiation so that the examination is legally regulated. Hospitals have to specify that "In case that the examination is taken out of the operating room, emergency room or intensive care units, the portable medical X-ray protective blocks should be set" in accordance with the standards of radiation protective facility in diagnostic radiological system. Some keep this regulation well, but mostly they do not keep. In this study, we shielded around the Collimator where the radiation is detected and then checked the change of dose regarding that of angles in portable tube and collimator before and after shielding. Moreover, we tried to figure out the effects of shielding on dose according to the distance change between patients' beds. As a result, the neighboring areas around the collimator are affected by the shielding. After shielding, the radiation is blocked 20% more than doing nothing. When doing the portable examination, the exposure doses are increased $0^{\circ}C$, $90^{\circ}C$ and $45^{\circ}C$ in order. At the time when the angle is set, the change of doses around the collimator decline after shielding. In addition, the exposure doses related to the distance of beds are less at 1m than 0.5m. In consideration of the shielding effects, putting the beds as far as possible is the best way to block the radiation, which is close to 100%. Next thing is shielding the collimator and its effect is about 20%, and it is more or less 10% by controlling the angles. When taking the portable examination, it is better to keep the patients and guardians far enough away to reduce the exposure doses. However, in case that the bed is fixed and the patient cannot move, it is suggested to shield around the collimator. Furthermore, $90^{\circ}C$ of collimator and tube is recommended. If it is not possible, the examination should be taken at $0^{\circ}C$ and $45^{\circ}C$ is better to be disallowed. The radiation-related workers should be aware of above results, and apply them to themselves in practice. Also, it is recommended to carry out researches and try hard to figure out the ways of reducing the exposure doses and shielding the radiation effectively.

• Journal of Distribution Science
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• v.10 no.4
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• pp.13-20
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• 2012

The "flextime" system, which was initially designed to maintain a balance between work and personal life, has recently received much attention as an alternative form of work, enabling employees to fully exert their creativity. Most studies show that the effects of flextime on performance, productivity, attitude toward the organization, absenteeism, and turnover differ between managerial and non-managerial workers. This suggests that workers' personal characteristics affect their preference for flextime by directly or indirectly influencing its result variables. As most Korean companies have not adopted the flextime system, little research has been conducted on it in Korea. Recently, Korean companies have been discussing flextime as one of several measures for enhancing international competitiveness. Therefore, this study aims to offer a theoretical framework for the introduction of the system by analyzing the effects of the precedent factors on the preference for flextime. Though not statistically significant, a higher preference for flextime is noted among workers over the age of 36. Older workers usually are more conservative and less adaptable to change but here the older Korean workers may be anxious and resistant. Additional research on workers in different types of businesses using improved research methods will lead to more meaningful results. Married workers display a lower preference to flextime than single workers. In Korea, the current atmosphere focused on a happy home encourages married workers to prefer regular work hours, enabling them to go to and from work on a regular schedule. This means that normal working hours, from morning to evening, are preferred as it is the most suitable system for families. However, this is not so in the case of single workers. Unmarried singles tend to prefer flextime for investing in self-development toward future prosperity, over the benefits of regular working-hours. Flextime is designed to meet their needs to some extent as it is helpful in maintaining a balance between work life and self-development. If flextime is selected, workers can spend mornings on self-development and work in the afternoons. Therefore, when flextime is introduced in Korea, it would be desirable to start with unmarried workers, to increase corporate creativity and productivity and develop individual potential. In particular, when the five-day workweek, the main concern for companies and labor unions, is adopted, synergy with flextime could be expected and a gradual implementation of flextime will be effective. Gender difference shows similar results to marital status with male workers displaying a higher preference for flextime. It is inferred that male workers' attitudes toward flextime are more favorable than female workers' because flextime enables self-development and work life to coexist. A relatively weak, though statistically significant, correlation exists between control position and flextime preference with inner-control-oriented workers displaying favorable attitudes toward flextime. Generally, inner-control-oriented workers tend to attribute the consequences caused by any person or partner relationship to themselves. Thus, when a new system is introduced they are likely to have less reluctance and fear than outer-control-oriented workers, because they think it is important to deal with the new system. A weak but slight correlation exists between the desire for achievement and flextime preference. People who have a higher desire for achievement are willing to consider the new system, especially if significant success is reasonably expected. This result is derived from a reasonable judgment that flextime offers an individual the time for self-development while the organization benefits from the resulting creativity and performance enhancements. Although not the primary analysis, a high correlation is found between control position and the desire for achievement, which is consistent with the results of previous research. The regression analysis not only supports the preceding ANOVA and correlation analysis but also shows the existence of a causal relationship. Married workers have a weak preference for flextime, which is consistent with the results of the preceding ANOVA. Relative to men, women have a weak preference for flextime. No statistically significant correlation was noticed for age. Inner-control-oriented workers prefer flextime more than outer-control-oriented workers as the former view the consequences of change to be their own responsibility. However, the preference for flextime seems to be weak. As expected, people with a higher desire for achievement have a stronger preference for flextime, presumably because the greater the desire for achievement, the stronger the spirit of challenging an uncertain future. No significant correlation exists between job satisfaction and flextime preference.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2A
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• pp.129-136
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• 2011

Recently studies on functional concrete with a photocatalytic material such as $TiO_2$ have actively been carried out in order to remove air pollutants. The absorbtion of $TiO_2$ from those studies is applied by it being directly mixed into concrete or by suspension coated on the surface. When it comes to the effectiveness, the former process is less than that of the latter compared with the $TiO_2$ use. As a result, the direct coating of $TiO_2$ on materials' surface is more used for effectiveness. The Surface spread of it needs to have a more than $400^{\circ}C$ heat treat done to stimulate the activation and adhesion of photocatalysis. Heat treat consequently leads hydration products in concrete to be dehydrated and shrunk and is the cause of cracking. The study produces $TiO_2$ used Sol-gel method which enables it to be coated with a low temperature treat, applies it to pearlite using Lightweight Aggregate Concrete fixed with a low temperature treat and evaluates the spread performance of it. In addition to this, the size of pearlite is divided into two types: One is 2.5 mm to 5.0 mm and the other is more than 5.0 mm for the benefit of finding out the removal characteristics of $CH_3CHO$ whether they are affected by pearlite size, mixing method and ratio with $TiO_2$ and elapsed time. The result of this experiment shows that although $TiO_2$ produced by Sol-gel method is treated with 120 temperature, it maintains a high spread rate on the XRF(X ray Florescence) quantitative analysis which ranks $TiO_2$ 38 percent, $SiO_2$ 29 percent and CaO 18 percent. In the size of perlite from 2.5 mm to 5.0 mm, the removal characteristic of $CH_3CHO$ from a low temperature heated Lightweight concrete appears 20 percent higher when $TiO_2$ with Sol-gel method is spreaded on the 7 percent of surface. In other words, the removal rate is 94 percent compared with the 72 percent where $TiO_2$ is mixed in 10 percent surface. In more than 5.0 mm sized perlite, the removal rate of $CH_3CHO$, when $TiO_2$ is mixed with 10 percent, is 69 percent, which is similar with that of the previous case. It suggests that the size of pearlite has little effects on the removal rate of $CH_3CHO$. In terms of Elapsed time, the removal characteristic seems apparent at the early stage, where the average removal rate for the first 10 hours takes up 84 percent compared with that of 20 hours.

• Journal of Animal Science and Technology
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• v.54 no.2
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• pp.89-94
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• 2012

The objective of this study was to estimate the genetic parameters and breeding value of swine using their economic traits. The traits considered were age at 90 kilograms body weight (D90 kg), backfat thickness (BF) and eye muscle area (EMA). Estimation of genetic parameters and breeding value from 18,668 heads considering the economic traits were based on farm performance data from May 2007 to April 2011. Estimation of genetic parameters based on economic traits revealed that the single best model was fitted after finding source of variance on fixed and random effects and estimated by a multiple trait model using DF-REML (Derivative-FREE Restricted Maximum Likelihood). In this study, the estimated heritabilities of Duroc, Berkshire, Landrace and Yorkshire were about 0.22-0.59 for the D90 kg, 0.47-0.62 for the BF and 0.23-0.37 for the EMA. Genetic correlation of D90 kg with BF and EMA of the four breeds were -0.01-0.24 and -0.35--0.23, respectively. Moreover, the genetic correlation of BF with EMA was -0.68--0.17. On the other hand, the phenotypic correlation of D90 kg with BF and EMA of the four breeds were about 0.01-0.11 and -0.37--0.21, respectively, while the phenotypic correlation of BF with EMA was -0.68--0.17. Results showed that the genetic trends of breeding value every year were decreasing for D90 kg, increasing for BF while for EMA inconsistent values were obtained.