• Title/Summary/Keyword: Composition

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The synthesis of dextran from rice hydrolysates using Gluconobacter oxydans KACC 19357 bioconversion (Gluconobacter oxydans 생물전환을 통한 쌀 가수분해물 유래 dextran 합성)

  • Seung-Min Baek;Hyun Ji Lee;Legesse Shiferaw Chewaka;Chan Soon Park;Bo-Ram Park
    • Food Science and Preservation
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    • v.31 no.1
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    • pp.149-160
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    • 2024
  • Dextran is a glucose homo-polysaccharide with a predominantly α-1,6 glycosidic linkage of microbial source and is known to be produced primarily by lactic acid bacteria. However, it can also be obtained through the dextran dextrinase of acetic acid bacteria (Gluconobacter oxydans). The dextrin-based dextran was obtained from rice starch using G. oxydans fermentation of rice hydrolysate, and its properties were studied. Both dextrin- and rice hydrolysate-added media maintained the OD value of 6 after 20 h of incubation with acetic acid bacteria, and the gel permeation chromatography (GPC) analysis of the supernatant after 72 h of incubation confirmed that a polymeric material with DP of 480 and 405, which was different from the composition of the substrate in the medium, was produced. The glucose linkage pattern of the polysaccharide was confirmed using the proton nuclear magnetic resonance (1H-NMR) and the increased α-1,4:α-1,6 bond ratio from 0.23 and 0.13 to 1:2.37 and 1:4.4, respectively, indicating that the main bonds were converted to α-1,6 bonds. The treatment of dextrin with a rat-derived alpha-glucosidase digestive enzyme resulted in a slow release of glucose, suggesting that rice hydrolysate can be converted to dextran using acetic acid bacteria with glycosyltransferase activity to produce high-value bio-materials with slowly digestible properties.

Effects on antioxidant, whitening, and anti-wrinkle improvement of ethanol extracts from fermented Trigonotis radicans var. sericea by Lactobacillus brevis (Lactobacillus brevis 발효가 참꽃마리(Trigonotis radicans var. sericea) 에탄올 추출물의 항산화, 미백 및 주름 개선 활성에 미치는 영향)

  • Da-Eun Jeong;Ji-Hye Kim;Byung-Oh Kim;Young-Je Cho
    • Food Science and Preservation
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    • v.31 no.1
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    • pp.173-182
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    • 2024
  • This study was designed to compare the effects on antioxidant, whitening, and anti-wrinkle improvement of 60% ethanol extracts from Trigonotis radicans var. sericea (TR) and Lactobacillus brevis-fermented T. radicans var. sericea (FTR). The total phenolics contents of TR was 18.6 mg/g, and FTR was 18.2 mg/g. The HPLC analysis confirmed more phenolic compounds were produced in FTR by bioconversion than in TR. The FTR showed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity than TR. The results of the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation decolorization assay, FTR and TR showed higher activity than BHT (positive control). The FTR (1.21-1.29 PF) showed higher antioxidant protection factor (PF) activity than the TR (1.15-1.22 PF) and showed higher tyrosinase, collagenase and elastase inhibitory activities. This results showed L. brevis -fermentation of Trigonotis radicans var. sericea changed the composition profile and has effects on antioxidant, whitening and anti-wrinkle improvement.

A Study on the Origin of Human Governance Periods in the Hidden Stems (인원용사(人元用事)의 연원에 관한 연구)

  • Won-Ho Choi;Na-Hyun Kim;Ki-Seung Kim
    • Industry Promotion Research
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    • v.9 no.1
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    • pp.203-212
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    • 2024
  • The purpose of this study is to examine the validity of Hidden Stems (支藏干) in the Four Pillars of Destiny with regard to the use of human governance periods in the hidden stems (人元用事). First, there is a theory of assigning period of governance for designated constituents (司令論) in the Hidden Stems of the Earthly Branch. Second, there is a theory that determines the structure of the Four Pillars by the Exposed Constituent from the Hidden Stems (透出論) in the Month Earthly Branch. Since these two theories conflict with each other and cause confusions, this study examined the theory of Hidden Stems in the Four Pillars Classics and examined the historical development of governance period for constituent hidden stems and their validity. The results of the study are as follows: Firstly, the number of dates assigned to respective constituents does not correspond to the calendarical principle, and the assignment of the governance dates for each constituent does not correspond to the principles proposed in ancient books of Four Pillars. Second, though it is said in the Classics that 72 days are equally assigned to each of the Five Elements, actual distributed days for the five elements was 65 days for Wood, 55 days for Fire, 100 days for Earth, 65 days for Metal, and 65 days for Water. Third, though it is said that 7 days should be designated to Yang Earth Mu for the months of Tiger 寅, Monkey, Snake, and Pig, it is logically more legitimate to assign those days to Yin Earth Ki since the month before Tiger is Ox, and the month before Monkey is Goat. Lastly, rationale behind assigning Ki Earth only to Horse Oh as constituting Hidden Stem while disregarding months of Rat, Rabbit, and Rooster is considered not reasonable. Looking at these results comprehensively, it is concluded that the Exposed Constituent theory is logically more appropriate than Assigned Governance theory.

Hydrochemistry, Isotopic Characteristics, and Formation Model Geothermal Waters in Dongrae, Busan, South Korea (부산 동래 온천수의 수리화학 및 동위원소 특성, 생성모델 연구)

  • Yujin Lee;Chanho Jeong;Yongcheon Lee
    • The Journal of Engineering Geology
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    • v.34 no.2
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    • pp.229-248
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    • 2024
  • This investigated the hydrogeochemical and isotopic characteristics of geothermal waters, groundwaters, and surface waters in Dongrae-gu, Busan, South Korea, in order to determine the origins of the salinity components in the geothermal waters, and their formation mechanisms and heat sources The geothermal waters are Na-Cl-type, distinct from surrounding groundwaters (Na-HCO3- and, Ca-HCO3- (SO4, Cl)-type) and surface waters (Ca-HCO3(SO4, Cl)-type). This indicates the geothermal waters formed at depth as compared with the groundwaters. δ18O and δD values of the geothermal waters are relatively depleted as compared with the groundwaters, due to altitude effects and deep circulation of the geothermal waters. Helium and neon isotope ratios (3 He/4He and, 4He/20Ne) of the geothermal waters plot on a single mixing line between mantle (3He = 3.76~4.01%) and crust (4He = 95.99~96.24 %), indirectly suggesting that the heat source is due to the decay of radioactive elements in rocks. The geothermal reservoir temperatures were calculated using the silica-enthalpy and Giggenbach models, yielding values of 82~130℃, and the depth of the geothermal reservoir is estimated to be 1.7~2.9 km below the surface. The correlation between Cl/Na and Cl/HCO3 for the Dongrae geothermal waters requires the input of salty water. The supply of saline composition is interpreted due to the dissolution of residual paleo-seawater.

A study on improving self-inference performance through iterative retraining of false positives of deep-learning object detection in tunnels (터널 내 딥러닝 객체인식 오탐지 데이터의 반복 재학습을 통한 자가 추론 성능 향상 방법에 관한 연구)

  • Kyu Beom Lee;Hyu-Soung Shin
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.26 no.2
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    • pp.129-152
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    • 2024
  • In the application of deep learning object detection via CCTV in tunnels, a large number of false positive detections occur due to the poor environmental conditions of tunnels, such as low illumination and severe perspective effect. This problem directly impacts the reliability of the tunnel CCTV-based accident detection system reliant on object detection performance. Hence, it is necessary to reduce the number of false positive detections while also enhancing the number of true positive detections. Based on a deep learning object detection model, this paper proposes a false positive data training method that not only reduces false positives but also improves true positive detection performance through retraining of false positive data. This paper's false positive data training method is based on the following steps: initial training of a training dataset - inference of a validation dataset - correction of false positive data and dataset composition - addition to the training dataset and retraining. In this paper, experiments were conducted to verify the performance of this method. First, the optimal hyperparameters of the deep learning object detection model to be applied in this experiment were determined through previous experiments. Then, in this experiment, training image format was determined, and experiments were conducted sequentially to check the long-term performance improvement through retraining of repeated false detection datasets. As a result, in the first experiment, it was found that the inclusion of the background in the inferred image was more advantageous for object detection performance than the removal of the background excluding the object. In the second experiment, it was found that retraining by accumulating false positives from each level of retraining was more advantageous than retraining independently for each level of retraining in terms of continuous improvement of object detection performance. After retraining the false positive data with the method determined in the two experiments, the car object class showed excellent inference performance with an AP value of 0.95 or higher after the first retraining, and by the fifth retraining, the inference performance was improved by about 1.06 times compared to the initial inference. And the person object class continued to improve its inference performance as retraining progressed, and by the 18th retraining, it showed that it could self-improve its inference performance by more than 2.3 times compared to the initial inference.

Effects of drumming exercise on the autonomic nervous system in overweight women (드러밍 운동이 과체중 여성의 자율신경계에 미치는 영향)

  • Jeong In Kwon;Jae Hoon Lee;Joon Yong Cho;Yoo Sung Oh
    • Journal of the Korean Applied Science and Technology
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    • v.41 no.2
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    • pp.219-232
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    • 2024
  • The aim of this study was to explore the impact of body mass index (BMI) and drumming exercise on autonomic nervous system function in adult women. Ten adult women (aged 30-50) were divided into two groups based on their BMI: a normal BMI group (Low BMI, LBMI < 23 kg/m2) and an overweight BMI group (High BMI, HBMI > 23 kg/m2). Both groups participated in a drumming exercise program, consisting of 50-minute sessions, three times a week, for a duration of 8 weeks. Body composition and heart rate variability were assessed before and after the 8-week exercise period. Heart rate variability was evaluated using linear analysis in the time domain and frequency domain. Additionally, non-linear analysis was conducted using a Poincaré plot. The autonomic nervous system index was determined by measuring parasympathetic nervous system index and sympathetic nervous system index. Following the 8-week intervention, the HBMI group exhibited a significant decrease in weight (p=0.034), BMI (p=0.044), body fat mass (p=0.032), and waist circumference (p=0.013) compared to the LBMI group. Furthermore, the HBMI group demonstrated significant increases in RMSSD (p=0.018) and TP (p=0.033) in linear analysis, as well as SD1 (p=0.018) in non-linear analysis and PNS Index (p=0.040) compared to the LBMI group. RMSSD, SD1, and PNS Index serve as indicators of parasympathetic nervous system activity in linear and non-linear analyses, respectively. These findings indicate that drumming exercise significantly enhances autonomic nervous system function in overweight women.

Analysis of Amino Acids, Fatty Acids, and Antioxidant Activities of Prunus yedoensis Matsum. Bark Extracts (왕벚나무 수피 추출물의 아미노산, 지방산 분석 및 항산화 활성)

  • Sung-Hwan Park;Ye-Eun Choi;Jung-Mo Yang;Chae-Won Jeong;Hyun-Duck Jo;Ju-Hyun Cho
    • Journal of Food Hygiene and Safety
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    • v.39 no.3
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    • pp.288-298
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    • 2024
  • This study aimed to investigate the amino acid content, fatty acid composition, total flavonoid and phenol contents, and antioxidant activities of Prunus yedoensis Matsum. bark extracts using various extraction solvents. Through amino acid analysis, 13 amino acids were detected in extracts obtained using hot water, 30% ethanol, and 70% ethanol. The major amino acids were identified as aspartic acid, arginine, and proline, and the total amino acid content was 0.17%, 0.16%, and 0.09%, respectively. Fatty acid analysis showed a saturated fatty acid (SFA) ratio of 62.7-66.7% in extracts obtained using hot water, 30% ethanol, and 70% ethanol, with the primary fatty acid identified as palmitic acid. The total flavonoid and polyphenol contents were 727.70-769.87 mg quercetin equivalent (QE)/ g and 309.24-348.09 mg gallic acid equivalent (GAE)/g, respectively, in extracts obtained using hot water, 30% ethanol, and 70% ethanol extracts. Measurements of antioxidant activity confirmed that extracts obtained using hot water, 30% ethanol, and 70% ethanol extracts increased the antioxidant effect in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, and ferric reducing antioxidant power (FRAP) in a concentration-dependent manner. A high correlation was observed between the total flavonoid content, total polyphenol content, and antioxidant activities of the extracts. This study provides data and novel insights for the development of functional food materials using P. yedoensis Matsum. bark extracts.

A Study on the Development of Educational Smart App. for Home Economics Classes(1st): Focusing on 'Clothing Preparation Planning and Selection' (가정과수업을 위한 교육용 스마트 앱(App) 개발연구(제1보): 중1 기술·가정 '의복 마련 계획과 선택'단원을 중심으로)

  • Kim, Gyuri;Wee, Eunhah
    • Journal of Korean Home Economics Education Association
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    • v.35 no.3
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    • pp.47-66
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    • 2023
  • The purpose of this study was to develop an educational smart app for classes by reconstructing some of the teaching-learning contents of the clothing preparation planning within the 'clothing preparation planning and selection' curriculum unit. To this end, a teaching-learning process plan was planned for the classes, a smart app was developed for classes, and feedback from home economics teachers and app development experts was received for the developed app. The main composition of the developed app consists of five steps. The first step is to set up a profile using a real photo, ZEPETO or Galaxy emoji, or iPhone Memoji. In the second step, students make a list of clothes by figuring out the types, quantities and conditions of their exisitng wardrobe items. Each piece of clothing is assigned an individual registration number, and stduents can take pictures of the front and back, along with describing key attributes such as type, color, season-appropriateness, purchase date, and current status. Step three guides students in deciding which garments to retain and which to discard. Building on the clothing inventory from the previous step, students classify items to keep and items to dispose of. In Step 4, Deciding How to Arrange Clothing, students decide how to arrange clothing by filling out an alternative scorecard. Through this process, students can learn in advance the subsection of resource management and self-reliance, laying the foundationa for future learning in 'Practice of Rational Consumption Life'. Lastly, in the fifth stage of determining the disposal method, this stage is to develop practical problem-oriented classes on how to dispose of the clothes to be discarded in the thirrd stage by exploring various disposal methods, engaging in group discussions, and sharing opinions. This study is meaningful as a case study as an attempt to develop a smart app for education by an instructor to align teaching plans and educational content with achievement standards for the class. In the future, upgrades will have to be made through user application.

A Study Concerning Health Needs in Rural Korea (농촌(農村) 주민(住民)들의 의료필요도(醫療必要度)에 관(關)한 연구(硏究))

  • Lee, Sung-Kwan;Kim, Doo-Hie;Jung, Jong-Hak;Chunge, Keuk-Soo;Park, Sang-Bin;Choy, Chung-Hun;Heng, Sun-Ho;Rah, Jin-Hoon
    • Journal of Preventive Medicine and Public Health
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    • v.7 no.1
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    • pp.29-94
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    • 1974
  • Today most developed countries provide modern medical care for most of the population. The rural area is the more neglected area in the medical and health field. In public health, the philosophy is that medical care for in maintenance of health is a basic right of man; it should not be discriminated against racial, environmental or financial situations. The deficiency of the medical care system, cultural bias, economic development, and ignorance of the residents about health care brought about the shortage of medical personnel and facilities on the rural areas. Moreover, medical students and physicians have been taught less about rural health care than about urban health care. Medical care, therefore, is insufficient in terms of health care personnel/and facilities in rural areas. Under such a situation, there is growing concern about the health problems among the rural population. The findings presented in this report are useful measures of the major health problems and even more important, as a guide to planning for improved medical care systems. It is hoped that findings from this study will be useful to those responsible for improving the delivery of health service for the rural population. Objectives: -to determine the health status of the residents in the rural areas. -to assess the rural population's needs in terms of health and medical care. -to make recommendations concerning improvement in the delivery of health and medical care for the rural population. Procedures: For the sampling design, the ideal would be to sample according to the proportion of the composition age-groups. As the health problems would be different by group, the sample was divided into 10 different age-groups. If the sample were allocated by proportion of composition of each age group, some age groups would be too small to estimate the health problem. The sample size of each age-group population was 100 people/age-groups. Personal interviews were conducted by specially trained medical students. The interviews dealt at length with current health status, medical care problems, utilization of medical services, medical cost paid for medical care and attitudes toward health. In addition, more information was gained from the public health field, including environmental sanitation, maternal and child health, family planning, tuberculosis control, and dental health. The sample Sample size was one fourth of total population: 1,438 The aged 10-14 years showed the largest number of 254 and the aged under one year was the smallest number of 81. Participation in examination Examination sessions usually were held in the morning every Tuesday, Wenesday, and Thursday for 3 hours at each session at the Namchun Health station. In general, the rate of participation in medical examination was low especially in ages between 10-19 years old. The highest rate of participation among are groups was the under one year age-group by 100 percent. The lowest use rate as low as 3% of those in the age-groups 10-19 years who are attending junior and senior high school in Taegu city so the time was not convenient for them to recieve examinations. Among the over 20 years old group, the rate of participation of female was higher than that of males. The results are as follows: A. Publie health problems Population: The number of pre-school age group who required child health was 724, among them infants numbered 96. Number of eligible women aged 15-44 years was 1,279, and women with husband who need maternal health numbered 700. The age-group of 65 years or older was 201 needed more health care and 65 of them had disabilities. (Table 2). Environmental sanitation: Seventy-nine percent of the residents relied upon well water as a primary source of dringking water. Ninety-three percent of the drinking water supply was rated as unfited quality for drinking. More than 90% of latrines were unhygienic, in structure design and sanitation (Table 15). Maternal and child health: Maternal health Average number of pregnancies of eligible women was 4 times. There was almost no pre- and post-natal care. Pregnancy wastage Still births was 33 per 1,000 live births. Spontaneous abortion was 156 per 1,000 live births. Induced abortion was 137 per 1,000 live births. Delivery condition More than 90 percent of deliveries were conducted at home. Attendants at last delivery were laymen by 76% and delivery without attendants was 14%. The rate of non-sterilized scissors as an instrument used to cut the umbilical cord was as high as 54% and of sickles was 14%. The rate of difficult delivery counted for 3%. Maternal death rate estimates about 35 per 10,000 live births. Child health Consultation rate for child health was almost non existant. In general, vaccination rate of children was low; vaccination rates for children aged 0-5 years with BCG and small pox were 34 and 28 percent respectively. The rate of vaccination with DPT and Polio were 23 and 25% respectively but the rate of the complete three injections were as low as 5 and 3% respectively. The number of dead children was 280 per 1,000 living children. Infants death rate was 45 per 1,000 live births (Table 16), Family planning: Approval rate of married women for family planning was as high as 86%. The rate of experiences of contraception in the past was 51%. The current rate of contraception was 37%. Willingness to use contraception in the future was as high as 86% (Table 17). Tuberculosis control: Number of registration patients at the health center currently was 25. The number indicates one eighth of estimate number of tuberculosis in the area. Number of discharged cases in the past accounted for 79 which showed 50% of active cases when discharged time. Rate of complete treatment among reasons of discharge in the past as low as 28%. There needs to be a follow up observation of the discharged cases (Table 18). Dental problems: More than 50% of the total population have at least one or more dental problems. (Table 19) B. Medical care problems Incidence rate: 1. In one month Incidence rate of medical care problems during one month was 19.6 percent. Among these health problems which required rest at home were 11.8 percent. The estimated number of patients in the total population is 1,206. The health problems reported most frequently in interviews during one month are: GI trouble, respiratory disease, neuralgia, skin disease, and communicable disease-in that order, The rate of health problems by age groups was highest in the 1-4 age group and in the 60 years or over age group, the lowest rate was the 10-14 year age group. In general, 0-29 year age group except the 1-4 year age group was low incidence rate. After 30 years old the rate of health problems increases gradually with aging. Eighty-three percent of health problems that occured during one month were solved by primary medical care procedures. Seventeen percent of health problems needed secondary care. Days rested at home because of illness during one month were 0.7 days per interviewee and 8days per patient and it accounts for 2,161 days for the total productive population in the area. (Table 20) 2. In a year The incidence rate of medical care problems during a year was 74.8%, among them health problems which required rest at home was 37 percent. Estimated number of patients in the total population during a year was 4,600. The health problems that occured most frequently among the interviewees during a year were: Cold (30%), GI trouble (18), respiratory disease (11), anemia (10), diarrhea (10), neuralgia (10), parasite disease (9), ENT (7), skin (7), headache (7), trauma (4), communicable disease (3), and circulatory disease (3) -in that order. The rate of health problems by age groups was highest in the infants group, thereafter the rate decreased gradually until the age 15-19 year age group which showed the lowest, and then the rate increased gradually with aging. Eighty-seven percent of health problems during a year were solved by primary medical care. Thirteen percent of them needed secondary medical care procedures. Days rested at home because of illness during a year were 16 days per interviewee and 44 days per patient and it accounted for 57,335 days lost among productive age group in the area (Table 21). Among those given medical examination, the conditions observed most frequently were respiratory disease, GI trouble, parasite disease, neuralgia, skin disease, trauma, tuberculosis, anemia, chronic obstructive lung disease, eye disorders-in that order (Table 22). The main health problems required secondary medical care are as fellows: (previous page). Utilization of medical care (treatment) The rate of treatment by various medical facilities for all health problems during one month was 73 percent. The rate of receiving of medical care of those who have health problems which required rest at home was 52% while the rate of those who have health problems which did not required rest was 61 percent (Table 23). The rate of receiving of medical care for all health problems during a year was 67 percent. The rate of receiving of medical care of those who have health problems which required rest at home was 82 percent while the rate of those who have health problems which did not required rest was as low as 53 percent (Table 24). Types of medical facilitied used were as follows: Hospital and clinics: 32-35% Herb clinics: 9-10% Drugstore: 53-58% Hospitalization Rate of hospitalization was 1.7% and the estimate number of hospitalizations among the total population during a year will be 107 persons (Table 25). Medical cost: Average medical cost per person during one month and a year were 171 and 2,800 won respectively. Average medical cost per patient during one month and a year were 1,109 and 3,740 won respectively. Average cost per household during a year was 15,800 won (Table 26, 27). Solution measures for health and medical care problems in rural area: A. Health problems which could be solved by paramedical workers such as nurses, midwives and aid nurses etc. are as follows: 1. Improvement of environmental sanitation 2. MCH except medical care problems 3. Family planning except surgical intervention 4. Tuberculosis control except diagnosis and prescription 5. Dental care except operational intervention 6. Health education for residents for improvement of utilization of medical facilities and early diagnosis etc. B. Medical care problems 1. Eighty-five percent of health problems could be solved by primary care procedures by general practitioners. 2. Fifteen percent of health problems need secondary medical procedures by a specialist. C. Medical cost Concidering the economic situation in rural area the amount of 2,062 won per residents during a year will be burdensome, so financial assistance is needed gorvernment to solve health and medical care problems for rural people.

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Occurrence and Chemical Composition of White Mica from Zhenzigou Pb-Zn Deposit, China (중국 Zhenzigou 연-아연 광상의 백색운모 산상과 화학조성)

  • Yoo, Bong Chul
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.2
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    • pp.83-100
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    • 2022
  • The Zhenzigou Pb-Zn deposit, which is one of the largest Pb-Zn deposit in the northeast of China, is located at the Qingchengzi mineral field in Jiao Liao Ji belt. The geology of this deposit consists of Archean granulite, Paleoproterozoinc migmatitic granite, Paleo-Mesoproterozoic sodic granite, Paleoproterozoic Liaohe group, Mesozoic diorite and Mesozoic monzoritic granite. The Zhenzigou deposit which is a strata bound SEDEX or SEDEX type deposit occurs as layer ore and vein ore in Langzishan formation and Dashiqiao formation of the Paleoproterozoic Liaohe group. White mica from this deposit are occured only in layer ore and are classified four type (Type I : weak alteration (clastic dolomitic marble), Type II : strong alteration (dolomitic clastic rock), Type III : layer ore (dolomitic clastic rock), Type IV : layer ore (clastic dolomitic marble)). Type I white mica in weak alteration zone is associated with dolomite that is formed by dolomitization of hydrothermal metasomatism. Type II white mica in strong alteration zone is associated with dolomite, ankerite, quartz and alteration of K-feldspar by hydrothermal metasomatism. Type III white mica in layer ore is associated with dolomite, ankerite, calcite, quartz and alteration of K-feldspar by hydrothermal metasomatism. And type IV white mica in layer ore is associated with dolomite, quartz and alteration of K-feldspar by hydrothermal metasomatism. The structural formulars of white micas are determined to be (K0.92-0.80Na0.01-0.00Ca0.02-0.01Ba0.00Sr0.01-0.00)0.95-0.83(Al1.72-1.57Mg0.33-0.20Fe0.01-0.00Mn0.00Ti0.02-0.00Cr0.01-0.00V0.00Sb0.02-0.00Ni0.00Co0.02-0.00)1.99-1.90(Si3.40-3.29Al0.71-0.60)4.00O10(OH2.00-1.83F0.17-0.00)2.00, (K1.03-0.84Na0.03-0.00Ca0.08-0.00Ba0.00Sr0.01-0.00)1.08-0.85(Al1.85-1.65Mg0.20-0.06Fe0.10-0.03Mn0.00Ti0.05-0.00Cr0.03-0.00V0.01-0.00Sb0.02-0.00Ni0.00Co0.03-0.00)1.99-1.93(Si3.28-2.99Al1.01-0.72)4.00O10(OH1.96-1.90F0.10-0.04)2.00, (K1.06-0.90Na0.01-0.00Ca0.01-0.00Ba0.00Sr0.02-0.01)1.10-0.93(Al1.93-1.64Mg0.19-0.00Fe0.12-0.01Mn0.00Ti0.01-0.00Cr0.01-0.00V0.00Sb0.00Ni0.00Co0.05-0.01)2.01-1.94(Si3.32-2.96Al1.04-0.68)4.00O10(OH2.00-1.91F0.09-0.00)2.00 and (K0.91-0.83Na0.02-0.01Ca0.02-0.00Ba0.01-0.00Sr0.00)0.93-0.83(Al1.84-1.67Mg0.15-0.08Fe0.07-0.02Mn0.00Ti0.04-0.00Cr0.06-0.00V0.02-0.00Sb0.02-0.01Ni0.00Co0.00)2.00-1.92(Si3.27-3.16Al0.84-0.73)4.00O10(OH1.97-1.88F0.12-0.03)2.00, respectively. It indicated that white mica of from the Zhenzigou deposit has less K, Na and Ca, and more Si than theoretical dioctahedral mica. Compositional variations in white mica from the Zhenzigou deposit are caused by phengitic or Tschermark substitution [(Al3+)VI+(Al3+)IV <-> (Fe2+ or Mg2+)VI+(Si4+)IV] substitution. It means that the Fe in white mica exists as Fe2+ and Fe3+, but mainly as Fe2+. Therefore, white mica from layer ore of the Zhenzigou deposit was formed in the process of remelting and re-precipitation of pre-existed minerals by hydrothermal metasomatism origined metamorphism (greenschist facies) associated with Paleoproterozoic intrusion. And compositional variations in white mica from the Zhenzigou deposit are caused by phengitic or Tschermark substitution [(Al3+)VI+(Al3+)IV <-> (Fe2+ or Mg2+)VI+(Si4+)IV] substitution during hydrothermal metasomatism depending on wallrock type, alteration degree and ore/gangue mineral occurrence frequency.