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A Survey on Consumption Behaviors of the Fast-Foods in University Students (대학생의 패스트푸드 소비행태에 관한 연구)

  • Cho, Kyu-Seok;Im, Byoung-Soon;Kim, Seok-Eun;Kim, Gye-Woong
    • Korean Journal of Human Ecology
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    • v.14 no.2
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    • pp.313-319
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    • 2005
  • This survey was conducted in order to obtain the basic data for desirable consumption habits through investigation and analysis of university students' fast food consumption behaviors. Questionnaires were collected from a total of 374 male and female students living in big or small and medium-sized cities in August, 2004. The contents surveyed were utilization and expenses of fast foods, choice of fast foods, relationship between fast foods and a diet, and characteristics of fast food restaurants. The results obtained are summarized as follows: 1. The ratio of the surveyees varied according to gender, residence, and the size of a city they're living in. For example, males took up 48.66% of the surveyees, while females did 51.34%. The ratio of residents in apartments and stand-alone houses was 54.81% and 45.19% each. 47.33% of the respondents were living in big cities, while 52.67% of them in small and medium-sized cities. 2. 70.1% of the surveyees responded that they are with friends when having fast foods. There was a highly significant difference between male and female in the type of eating companions (p<0.001). The average number of days that they eat fast foods was 1 to 2 times a week, which accounted for 63.7% of the respondents. However, in the case of eating foods, there was no significant differences between two sexes. 3. 64.2% of the surveyees paid more than 20,000 won to buy fast foods for a week, which showed no significant differences between genders. They tend to split a bill, rather than one person pays all. There was a highly significant difference between genders in paying method (p<0.001). 4. 52.1 % of the respondents chose a menu themselves. Their most favored food was chickens (26.5%), which showed a statistically significant difference between genders (p<0.001). 46.8% of them preferred coke as a drink, which had no significant difference between genders. 42.2% of the surveyees had fast foods between lunch and dinner, which also had no significant difference between genders. The most important factor in choosing a menu was its taste (62.8%), which indicated a significant difference between males and females (p<0.05). 5. The preference to fast foods was due to the influence of western culture (36.4%) and eating-out habits (29.1%), which was significantly different between genders (p<0.05). Those who eat fast foods answered they have normal weight and normal body type (49.5%). 24.3% of them were relatively fat with significant difference between genders (p<0.05). 63.4% of the surveyees thought themselves not picky with foods, and there was a significant difference between genders (p<0.05). 78.3% of them mostly preferred franchise restaurants because they are convenient and cheap.

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A Study for Developing Music Therapy Activity Program for Development of Rudimentary Movement Phase of Spastic Cerebral Palsied Infant : Applying the techniques of Neurological Music Therapy (경직형 뇌성마비 유아의 초보운동단계 발달을 위한 음악치료활동 프로그램 개발 - 신경학적 음악치료의 기법을 활용하여)

  • Lee, Yoon Jin
    • Journal of Music and Human Behavior
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    • v.4 no.2
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    • pp.84-105
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    • 2007
  • Cerebral palsy is a collection of motor disorders resulting from damage to the central nervous system that arise in multiple handicaps including cognitive disorders, speech disorders, epilepsy, perception disorders, and emotion disorders. Today spastic cerebral palsy has become more prevalent because intensive care for newborns has resulted in higher survival rates for very small premature babies. Since the children grow the fastest in order for a development during one year after birth, the therapeutic intervention is provided as early as possible to the children with cerebral palsy. After seven year old, there is no effect of intervention. So, the necessity of early intervention to spastic cerebral palsied infants is increasing. The purpose of this study is to develop the music therapy activity program using the techniques of neurological music therapy(NMT), the therapeutic application of music to dysfunctions due to neurologic disease of the human nervous system, for rudimentary movement phase of spastic cerebral palsied infant. This music therapy activity program was developed on the basis of the major developmental tasks of the rudimentary movement phase, the period that children can acquire the most basic movement function at the 0 to 2. Then the developmental characteristics of spastic cerebral palsy were applied to this music therapy activity program. This music therapy activity program was classified to three domains, those are stability, locomotion, and manipulation. This study has been consisted of three steps, those are the development of the activities, the evaluation of the activities by th panels, and the adjustment and complement of the activities. Reviewing literatures and interviews were done for the development of the activities, and the evaluation the activities was done by seven music therapists. In the evaluation steps, the questionnaire was used for estimating the content validity and application efficiency. The adjustment and complement of the activities were evaluated by the panels who were participating in the music therapy for cerebral palsied children in the clinical setting, and the results of the adjustment and complement were confirmed by the panels. The evaluation was presented in a mean value with the comment of the panels. In conclusion, the music therapy activity program for the spastic cerebral palsied infants using the techniques of NMT was developed on the basis of the major developmental tasks of the rudimentary movement phase. The program is comprised of 38 activities, those are 14 activities for developing the stability, 10 activities for developing the locomotion, and 14 activities for developing the manipulation. The programed activities would bring out the answers in the affirmative for the conformance with infants' development phase, the harmony between the objective and the activity, the conformance with the cerebral palsied infants, the properness of the music and the instruments, and the utility in the clinic field. This results mean that this developed music activity program is appropriate to help spastic cerebral palsied infants progress their movement development by stages.

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Estimation of Genetic Variations and Selection of Superior Lines from Diallel Crosses in Layer Chicken (산란계종의 잡종강세 이용을 위한 유전학적 기초연구와 우량교배조합 선발에 관한 연구)

  • 오봉국;한재용;손시환;박태진
    • Korean Journal of Poultry Science
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    • v.13 no.1
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    • pp.1-14
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    • 1986
  • The subject of this study was to obtain some genetic information for developing superior layer chickens. Heterosis and combining ability effects were estimated with 5,759 progenies of full diallel crosses of 6 strains in White Leghorn. Fertility, hatchability, brooder-house viability, rearing- house viability, laying-house viability, age at 1st egg laying, body weight at 1st egg laying, average egg weight, hen-day egg production, hen-housed egg production, and feed conversion were investigated and analyzed into heterosis effect, general combining ability, specific combining ability and reciprocal effect by Grilling's model I. The results obtained were summarized as follows; 1. The general performance of each traits was 94.76% in fertility, 74.05% in hatchability, 97.47% in brooder-house viability, 99.72% in rearing-house viability, 93.81% in laying-house viability, 150 day in the age at 1st egg laying, 1,505g in the body weight at 1st egg laying, 60.08g in average egg weight, 77.11% in hen-day egg production, 269.8 eggs in hen-housed egg Production, and 2.44 in feed conversion. 2. The heterosis effects were estimated to -0.66%, 9.58%, 0.26%, 1.83%, -3.87%, 3.63%, 0.96%, 4.23%, 6.4%, and -0.8%, in fertility, hatchability, brooder-house viability, laying-house viability, the age at 1st egg laying, the body weight at 1st egg laying, average egg weight, hen-day egg Production, hen-housed egg production and feed conversion, respectively. 3. The results obtained from analysis of combining ability were as follows ; 1) Estimates of general combining ability, specific combining ability and reciprocal effects were not high in fertility. It was considered that fertility was mainly affected by environmental factors. In the hatchability, the general combining ability was more important than specific combining ability and reciprocal effects, and the superior strains were K and V which the additive genetic effects were very high. 2) In the brooder-house viability and laying-house viability, specific combining ability and reciprocal effects appeared to be important and the combinations of K${\times}$A and A${\times}$K were very superior. 3) In the feed conversion and average egg weight, general combining ability was more important compared with specific combining ability and reciprocal effects. On the basis of combining ability the superior strains were F, K and B in feed conversion, F and B in the average egg weight. 4) General combining ability, specific combining ability and reciprocal effects were important in the age at 1st egg laying and the combination of V ${\times}$F, F${\times}$K and B${\times}$F were very useful on the basis of these effects. In the body weight at 1st egg laying, general combining ability was more important than specific combining ability and reciprocal effects, relatively. The K, F and E strains were recommended to develop the light strain in the body weight at 1st egg laying. 5) General combining ability, specific combining ability and reciprocal effects were important in the hen-day egg production and hen-housed egg production. The combinations of F${\times}$K, A${\times}$K, and K${\times}$A were proper for developing these traits. 4. In general, high general combining ability effects were estimated for hatchability, body weight at 1st egg laying, average egg weight, hen-day egg production, hen-housed egg production, and feed conversion and high specific combining ability effects for brooder-house viability, laying house viability, age at 1st egg laying, hen-day egg production and hen-housed egg production, and high reciprocal effects for the age at 1st egg laying.

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Studies on the Post-hatching Development of the Testis in Korean Native Chickens (한국 재래 닭 부화 후 고환 발달에 관한 연구)

  • Jang, B.G.;Tae, H.J.;Choi, C.H.;Park, Y.J.;Park, B.Y.;Park, S.Y.;Kang, H.S.;Kim, N.S.;Lee, Y.H.;Yang, H.H.;Ahn, D.C.;Kim, I.S.
    • Korean Journal of Poultry Science
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    • v.33 no.3
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    • pp.171-179
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    • 2006
  • Changes in the chicken testis from hatching to adulthood were studied in Korean native chickens of 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 21, 24, 28, 32, 44, 52 and 64 weeks (n=13 chickens per group) of age. The present study was to investigate in more detail the post-hatching development of testis in Korean native chickens. Testes of chickens were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in Epon-araldite. Using $1{\mu}m$ sections stained with methylene blue-azure II, qualitative and quantitative(stereological) morphological studies were performed. Sperm production was measured by routine technique. The average volume of a testis of 1 week old Korean native chickens was determined as 0.015 g and the parameter increased linearly from 1 week to 21 weeks days (28.9 g), and did not change from 21 weeks to 64 weeks. The volume density of the seminiferous tubules increased with age from 32.6% at week 1 to 92.89% at week 64. The volume density of the interstitium represents 67.4% of the testicular parenchyma at week 1. This proportion progressively diminished during development to reach a value of 7.11% at week 64. Total sperm production per testis increased significantly from 18 weeks to 28 weeks and remained unchanged. Sperm production per 1 g testis increased significantly from 18 weeks to 28 weeks, did not change significantly from 28 weeks to 52 weeks, and declined significantly at 64 weeks of age. The average diameter of the seminiferous tubules gradually increased with age from 1 week $(42.4{\mu}m)$ to 21 weeks $(412.8{\mu}m)$. The length of the seminiferous tubules was 0.34 m at 1 week, increased significantly in subsequent age groups and reached 72.2 m by weeks 64. The stage of germ cell development in seminiferous tubules was classified as 1) spermatogonia $(1\sim8\;weeks)$, 2) spermatogonia and spermatocytes $(10\sim12\;weeks)$, 3) spermatogonia, spermatocytes and round spermatids $(14\sim16\;weeks)$, and 4) speramatogonia, spermatocytes, spermatids and spermatozoa $(18\sim64\;weeks)$. These results clarified the pattern of changes in the testicular development in Korean native chickens from hatching to adulthood as 1) neonatal-prepubertal $(1\sim12\;weeks)$, 2) puberty$(14\sim18\;weeks)$, and adult$(21\sim64\;weeks)$.

Effect of Dietary Energy, Protein on Growth and Blood Composition of Cross Bred Chicks (유색육용계의 성장과 혈액성상에 사료단백질 및 에너지가 미치는 영향)

  • Jeong, Y.D.;Ryu, K.S.
    • Korean Journal of Poultry Science
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    • v.35 no.3
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    • pp.291-302
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    • 2008
  • To acquire essentially necessary basic data to establish feeding system by verifying appropriate dietary energy and protein level for the growth of commercial slow growing broiler chicks within the country, two experiments were conducted for 5 weeks. One day old, 1,404 male and female broiler chicks were used for the experiments, and 26 chicks were placed at each pen. The energy level of feed was maintained about 3,000 or 3,100 kg/kcal for whole breeding period of 5 weeks, and protein content was adjusted about 20, 21, and 22% during the first two weeks and the content was adjusted to 18, 19, 20, 21, and 22% from the 3 to 5 weeks old of the experiment. The categories of body weight and feed intake amount were monitored to calculate the productivity and blood sampling was conducted for the analysis at the end of each experiment. Experiment 1:Although the productivity by the ME content difference during $0{\sim}2$ weeks did not have significant difference and the body weight increase by the difference of CP content and feed intake amount did not have much difference, the feed requirement rate was statistically improved in CP 21 and 22% treatment groups compared to the CP 20% group (P<0.05). The feed ME 3,100 kcal/kg treated group during $3{\sim}5$ weeks after starting the experiment revealed to show improved feed requirement rate (P<0.05). Within the period of experiment, the CP 22% treated group resulted to show significant body weight increase compared to the groups treated with low levels of CP (P<0.05) and the feed requirement rate was improved in high CP treated group compared to low CP treated groups, but the feed intake amount did not show significant difference between treated groups. During the experiment period, the body weight increase and feed requirement rate revealed to interact between ME and CP (P<0.05). During the whole experiment period of the 5 weeks, the feed requirement rate was improved in ME 3,100 kcal/kg treated group than the groups treated with ME 3,000 kcal/kg, and the CP (20) 18% treatment groups resulted to show higher values than other treatment groups (P<0.05). Body weight increase was high in CP (22) 22% treated groups than those of CP (21) 21% and (20) 18% treated groups, and the interaction between ME and CP was found at body weight increase and feed requirement rate (P<0.05). Although blood albumin and total cholesterol levels were elevated in ME 3,100 kcal/kg treated group than ME 3,000 kcal/kg treated group, but neutral fat content was reduced (P<0.05). On the other hand, the total cholesterol content was increased in CP (22) 21% treated group than CP (22) 20% and CP (20) 18% treated groups (P<0.05). Experiment 2: The body weight increase in 0-2 weeks was higher in ME 3,100 kcal/kg treated group than ME 3,000 kcal/kg treated group, and it was highly improved in CP 22% treated group than CP 20% treated group by showing the interaction between CP and ME (P<0.05). The significant improvement of feed requirement rate was observed in CP 21% and 22% treated groups compared to CP 20% treated group (P<0.05). The productivity between the growth period from 3 to 5 weeks of age and whole growth period resulted to show no significant difference. Although no difference was observed in blood composition between treated groups, the interaction of ME and CP on cholesterol content was accepted at the range of P<0.05). Therefore, it is considered that the appropriate dietary protein level within feed for the physiology of growing broiler chicks was 22% or more for the first two weeks and protein level of 21% or 20% from 3 to 5 weeks old for the maximization of productivity. Even if the energy level within feed had some partial effects on the productivity, but did not show consistency. So, further experiments needto be conducted by differentiating the energy level.

Synthesis of a Dopamine Transporter Imaging Agent, N-(3-[$^{18}F$]fluoropropyl)-$2{\beta}$-carbomethoxy-$3{\beta}$-(4-iodophenyl)nortropane (도파민운반체 방사성추적자 N-(3-[$^{18}F$Fluoropropyl)-$2{\beta}$-carbomethoxy-$3{\beta}$-(4-iodophenyl)nortropane의 합성)

  • Choe, Yearn-Seong;Oh, Seung-Jun;Chi, Dae-Yoon;Kim, Sang-Eun;Choi, Yong;Lee, Kyung-Han;Kim, Byung-Tae
    • The Korean Journal of Nuclear Medicine
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    • v.33 no.3
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    • pp.298-305
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    • 1999
  • Purpose: N-(3-[$^{18}F$]Fluoropropyl)-$2{\beta}$-carbomethoxy-$3{\beta}$-(4-iodophenyl)nortropane [$^{18}F$]FP-CIT) has been shown to be very useful for imaging the dopamine transporter. However, synthesis of this radiotracer is somewhat troublesome. In this study, we used a new method for the preparation of [$^{18}F$]FP-CIT to increase radiochemical yield and effective specific activity. Materials and Methods: [$^{18}F$]FP-CIT was prepared by N-alkylation of nor-${\beta}$-CIT (2 mg) with 3-bromo-1-[$^{18}F$]fluoropropane in the presence of $Et_3N$ (5-6 drops of $DMF/CH_3CN$, $140^{\circ}C$, 20 min). 3-Bromo-1-[$^{18}F$]fluoropropane was synthesized from $5{\mu}L$ of 3-bromo-1-trifluoromethanesulfonyloxypropane (3-bromopropyl-1-triflate) and $nBu_4N^{18}F$ at $80^{\circ}C$. The final compound was purified by reverse phase HPLC and formulated in 13% ethanol in saline. Results: 3-Bromo-1-[$^{18}F$]fluoropropane was obtained from 3-bromopropyl-1-triflate and $nBu_4N^{18}F$ in 77-80% yield. N-Alkylation of nor-${\beta}$-CIT with 3-bromo-1-[$^{18}F$]fluoropropane was carried out at $140^{\circ}C$ using acetonitrile containing a small volume of DMF as the solvents. The overall yield of [$^{18}F$]FP-CIT was 5-10% (decay-corrected) with a radiochemical purity higher than 99% and effective specific activity higher than the one reported in the literature based on their HPLC data. The final [$^{18}F$]FP-CIT solution had the optimal pH (7.0) and it was pyrogen-free. Conclusion: In this study, 3-bromopropyl-1-triflate was used as the precursor for the [$^{18}F$]fluorination reaction and new conditions were developed for purification of [$^{18}F$]FP-CIT by HPLC. We established this new method for the preparation of [$^{18}F$]FP-CIT, which gave high effective specific activity and relatively good yield.

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Diving patterns and diving related disease of diving fishermen in Korea (수산물채취 잠수부의 작업특성과 잠수관련질환의 양상)

  • SaKong, Joon
    • Journal of Preventive Medicine and Public Health
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    • v.31 no.1 s.60
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    • pp.139-156
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    • 1998
  • Diving related disease including decompression sickness is an important occupational health problem and diving fishermen remain a fairly hazardous occupation in Korea. To prevent diving related disease, we investigate diving patterns, incidence of diving related diseases, and contributing factors of 433 diving fishermen of three coast interviewing and mailing questionnaire in 1996. Mean age of divers was 39.7 years, ranged from 24 to 58 years, 92.8% of these were male, and 58.4% of divers were high school graduates. Mean duration of work as a diver was 12.9 years, ranged from 2 to 40 years. It was found that 70.4% of divers were using hookah system, 22.2% of helmet, and only 2.5% SCUBA. About half of them have learned diving skills from other divers. The peak season of diving was from April to June and mean working days were 20.3 days per month during the peak season. On the average, the divers dived 5-6 times, ranged from 1 to 10 times a day with 51.1 minutes of diving time, ranged from 20 to 120 minutes, at 30 m or 40 m in depth, and 35.5 minute of interval on surface. Most divers ascended slowly making decompression stop, yet the decompression profile used was not based on any scientific knowledge except for their own experiences. It appeared that each diving system had slightly different diving patterns. There were 282(65.0%) divers that suffered from DCS in 1995 and 31.2% of divers were given recompression therapy at a medical facility since they worked as diving fishermen. Skin and musculoskeletal complaints were common symptoms of DCS and 39% of divers experienced a voiding difficulty. In univariate analysis, females have an increased frequency of DCS(93% vs 66% for males). Old age, long duration of work, helmet diving, diving time, diving depth, repetitive diving, and blow up were all contributing factors to DCS. It was found that most diving patterns exceed no decompression limit and did not use the standard decompression table. This suggests that most of divers are at high risk of developing diving related disease with prolonged dives and lengthy repetitive diving in deep depth. Considering the diving patterns and economic aspect of professional diving, the incidence of DCS among diving fishermen in Korea will not decrease in the near future. These findings suggest that periodical health surveillance for divers, and education of health and safety are important for reducing the risk of diving related disease in the population of diving fishermen.

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The relationships between lead exposure indicies and urinary δ-ALA by HPLC and colorimetric method in lead exposure workers (연노출근로자에 있어서 흡광광도법과 HPLC법에 의한 요중 δ-ALA 배설량과 연노출지표들 간의 관련성)

  • Ahn, Kyu-Dong;Lee, Sung-Soo;Hwangbo, Young;Lee, Gab-Soo;Yeon, You-Yong;Kim, Yong-Bae;Lee, Byung-Kook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.6 no.1
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    • pp.77-87
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    • 1996
  • In order to compare the difference of the measurement of delta aminolevulinic acid(${\delta}$-ALA) in urine between HPLC method(HALA) and colorimetric method(CALA), and also to provide useful information for the new diagnostic criteria of ${\delta}$-ALA in urine in lead poisoning, if at all possible in the future, authors studied 234 male lead workers who were selected from 7 storage battery factories, 3 secondary smelting industries, and 2 litharge making industries. Study subjects were selected on the basis of blood Zinc protoporphyrin(ZPP) level from low to high concentration to cover wide range of lead exposure. Study variables for this study were ${\delta}$-ALA measured by two different methods, blood lead(PbB), and blood ZPP. The results were as follows: 1. There was very high correlation between ${\delta}$-ALA measured by two method(r = 0.989 : HALA = -0.8194 + 0.8110 ${\times}$ CALA), but the value of CALA was measured about 2mg/L greater than HALA. 2. While the correlations of ${\delta}$-ALA by two method with blood lead and blood ZPP were 0.46 and 0.37 respectively, they were increased to 0.63 and 0.57 if ${\delta}$-ALA values were log-transformed. 3. Simple linear regression of ${\delta}$-ALA measured by two method on ZPP were as follows: CALA = 2.0421 + 0.0341 ${\times}$ ZPP ($R^2=0.1385$ p = 0.0001) HALA = 0.8006 + 0.0280 ${\times}$ ZPP ($R^2=0.1389$ p = 0.0001) 4. Simple linear regression of ${\delta}$-ALA measured by two method on PbB were as follows: CALA = - 0.4134 + 0.1545 ${\times}$ PbB ($R^2=0.2085$ p = 0.0001) HALA = -1.2893 + 0.1287 PbB ($R^2=0.2154$ p = 0.0001), 5. Simple linear regression of log-transformed ${\delta}$-ALA by two method on ZPP and PbB were as follows: logHALA = 0.3078 + 0.0060 ZPP ($R^2=0.3329$ p = 0.0001) logCALA = 1.0189 + 0.0044 ZPP ($R^2=0.3290$ p = 0.0001) logHALA = -0.0221 + 0.0246 PbB ($R^2=0.4046$ p = 0.0001) logCALA = 0.7662 + 0.0184 PbB ($R^2=0.4108$ p = 0.0001) 6. The cumulative percent of colorimetric method to detect lead workers whose value of PbS and ZPP were over screening level such as $40{\mu}/dl$ and $100{\mu}/dl$ respectively was higher than HPLC method if cut-off level of ${\delta}$-ALA for screening of lead poisoning was 5 mg/L. But if cut-off level of ${\delta}$-ALA measured by HPLC was reduced to 3 mg/L which is compatible to 5 mg/L of ${\delta}$-ALA measured by colorimetric method, there were good agreement between two methods and showed dose-response relationship with other lead exposure indices such as PbB and ZPP.

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Comparison between phosphorus absorption coefficient and Langmuir adsorption maximum (전토양(田土壤) 인산(燐酸)의 흡수계수(吸收係數)와 Langmuir 최대흡착량(最大吸着量)과의 비교연구(比較硏究))

  • Ryu, In Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.8 no.1
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    • pp.1-17
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    • 1975
  • Laboratory experiments on the phosphorus adsorption by soil were conducted to evaluate the parameters for determination of phosphorus adsorption capacity of soil, which serve as a basis for establishing the amount of phosphorus required to improve newly reclaimed soil and volcanic ash soil. The calculated Langmuir adsorption maxima varied from 6.2-32.9, 74.7-90.4 and 720-915mg p/100g soil for cultivated soils, non-cultivated soils, and volcanic ash soils respectively. The phosphorus absorption coefficient ranged from 116-179, 161-259 and 1,098-1,205mg p/100g soil for cultivated soils, non-cultivated soils, and volcanic ash soils respectively. The ratio of the phosphorus absorption coefficient to Langmuir adsorption maximum was low in soils of high phosphorus adsorption capacity (1.3-1.5) and high in soils of low phosphorus adsorption capacity (2.2-18.7). Changes in the amount of phosphurus adsorption induced by liming and preaddition of phosphorus were hadly detected by the phosphorus absorption coefficient, which is measured using a test solution with a relatively high phosphorus concentration. The Langmuir adsorption maximum was a more sensitive index of the phosphorus adsorption capacity. The Langmuir adsorption maxima of the non-cultivated soils, which were treated with an amount of calcium hydroxide equivalent to the exchangeable Al and incubated ($25-30^{\circ}C$) for 40 days at field capacity, were lower than the original soils. The change in the adorption maximum on incubation following the liming of soils was insignificant for other soils. The secondary adsorption maximum of soils, which received phosphorus equivalent to the Langmuir adsorption maximum of the limed soils incubated ($25-30^{\circ}C$) for 50 days at held capacity, was 74.5, 5.6 and 23.8% of the primary adsorption maximum for volcanic ash soils, non-cultivated soils, and cultivated soils respectively. The amount of phosphorus adsorbed by soils increased quadratically with the concentration of phosphorus solution added to the soils. The amount of phosphorus adsorbed by 5-g soil samples from 100ml of 100- and 1,000mg p/l solution for the mineral soils and volcanic ash soils respectively was found to be close to the Langmuir adsorption maximum. The amount of the phosphorus adsorbed at these concentrations is defined as a saturation adsorption maximum and proposed as a new parameter for the phosphorus adsorption capacity of the soil. The evaluation of the phosphorus adsorption capacity by the saturation adsorption maximum is regarded as a more practical method in that it obviates the need for the various concentrations used for the determination of the Langmuir adsorption maximum.

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A Statistical model to Predict soil Temperature by Combining the Yearly Oscillation Fourier Expansion and Meteorological Factors (연주기(年週期) Fourier 함수(函數)와 기상요소(氣象要素)에 의(依)한 지온예측(地溫豫測) 통계(統計) 모형(模型))

  • Jung, Yeong-Sang;Lee, Byun-Woo;Kim, Byung-Chang;Lee, Yang-Soo;Um, Ki-Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.23 no.2
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    • pp.87-93
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    • 1990
  • A statistical model to predict soil temperature from the ambient meteorological factors including mean, maximum and minimum air temperatures, precipitation, wind speed and snow depth combined with Fourier time series expansion was developed with the data measured at the Suwon Meteorolical Service from 1979 to 1988. The stepwise elimination technique was used for statistical analysis. For the yearly oscillation model for soil temperature with 8 terms of Fourier expansion, the mean square error was decreased with soil depth showing 2.30 for the surface temperature, and 1.34-0.42 for 5 to 500-cm soil temperatures. The $r^2$ ranged from 0.913 to 0.988. The number of lag days of air temperature by remainder analysis was 0 day for the soil surface temperature, -1 day for 5 to 30-cm soil temperature, and -2 days for 50-cm soil temperature. The number of lag days for precipitaion, snow depth and wind speed was -1 day for the 0 to 10-cm soil temperatures, and -2 to -3 days for the 30 to 50-cm soil teperatures. For the statistical soil temperature prediction model combined with the yearly oscillation terms and meteorological factors as remainder terms considering the lag days obtained above, the mean square error was 1.64 for the soil surfac temperature, and ranged 1.34-0.42 for 5 to 500cm soil temperatures. The model test with 1978 data independent to model development resulted in good agreement with $r^2$ ranged 0.976 to 0.996. The magnitudes of coeffcicients implied that the soil depth where daily meteorological variables night affect soil temperature was 30 to 50 cm. In the models, solar radiation was not included as a independent variable ; however, in a seperated analysis on relationship between the difference(${\Delta}Tmxs$) of the maximum soil temperature and the maximum air temperature and solar radiation(Rs ; $J\;m^{-2}$) under a corn canopy showed linear relationship as $${\Delta}Tmxs=0.902+1.924{\times}10^{-3}$$ Rs for leaf area index lower than 2 $${\Delta}Tmxs=0.274+8.881{\times}10^{-4}$$ Rs for leaf area index higher than 2.

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