• Title/Summary/Keyword: water index

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Physical Properties of the Hydrogel Using Alginate (Alginate가 포함된 하이드로겔의 물리적 특성)

  • Woo, Chul-min;Heo, Seongin;Lee, Hyun Mee
    • Journal of Korean Ophthalmic Optics Society
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    • v.20 no.4
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    • pp.463-469
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    • 2015
  • Purpose: A hydrogel including alginate and $CaCl_2$ extracted from seaweed was manufactured, and their physical properties were investigated. Also, its applicability as contact lenses was examined. Methods: A film-type sample used in this experiment was manufactured using 2-hydroxyethyl methacrylate (HEMA), which is the raw material of hydrogel contact lenses; azobisiobutyonitile (AIBN), which is an initiator and ethylenglycoldimethacrylate (EGDMA), which is a cross-linking agent. It was hydrated in a PBS solution for 24 hours, and an interpenetrating polymer network (IPN) was formed in 1% and 2% alginate and 1%, 3%, and 5% $CaCl_2$ solutions for 24 hours, respectively. Results: The measurement of the physical properties of the film after the IPN showed that the moisture content was 30.89~36.89%, the refractive index was 1.431~1.441, the contact angle was $62.98{\sim}80.45^{\circ}$, and the tensile strength was 2.378~4.215 ($gf/mm^2$). Also, the physical properties hardly changed as the content of alginate increased, and the moisture content decreased as the content of $CaCl_2$ increased. As a result of the IPN, the moisture content and contact angle decreased compared to those of basic HEMA, but the tensile strength increased. The tensile strength of the second IPN was higher than that of the first IPN. In the case of $CaCl_2$, for the sample polymerized for 24 hours and the second IPN sample with 2% alginate, the contact angle decreased as the content of $CaCl_2$ increased. Conclusions: In this study, the tensile strength increased as the content of $CaCl_2$ increased, and the wettability increased as a result of IPN of alginate and $CaCl_2$. The hydrogel containing the alginate and $CaCl_2$ was confirmed possible utilization as contact lens material.

A Study on Development of Evaluation Indicator for Golf Course User's Preference (골프장 이용자 선호도 평가지표 개발)

  • Seok, Young-Han;Moon, Seok-Ki;Lee, Eun-Yeob
    • Journal of the Korean Institute of Landscape Architecture
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    • v.38 no.4
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    • pp.25-34
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    • 2010
  • This study was conducted to develop evaluation indicators to improve athletic performance and operational management of golf courses and the results of the research are as follows. Through theoretical research and a preliminary professional survey, 15 on-going evaluations of golf course composition and operational management and 55 sub-evaluation indices were rejected while 10 on-going evaluations and 52 sub-evaluation indicators were reconfigured as final for environmental-friendliness, level of member services, level of human service of game personnel, difficulties of course, management level of the course, fairness of operational management, accessibility and location characteristic, traditions and ambiance of the golf club, quality of course, and course layout. When analyzing the important decision factors in golf course user preference evaluation indicators, the following contributed in the order of higher to lower contributions: the management level of the course, excellence of the course, level of human services for personnel, course layout and environmental-friendliness. When identifying the path coefficient of golf course evaluation indicators, the curvature of a hole and the length of the course had a causal effect on the 'course layout' section. Tournament facilities and various shot values had a causal relationship with 'excellence of the course', in the order of higher to lower, and convenience of waiting and fair allocation of reservations for 'fairness of operational management'. The history of the golf course and its environmental characteristics, history and culture of the region have relatively higher causal effects on 'traditions of the golf club' and geographical conditions on 'accessibility and location characteristics', pesticide and fertilizer usage and water pollution on 'environmental-friendliness', and member benefit and kindness of employees on 'level of member services'. The kindness and expertise of the game personnel had a relatively higher causal effect on the 'level of human services of game personnel', the location of tenning area, and location of OB and hazards on 'difficulties of course', and rough conditions and obstacles management on 'management level of the course'. There is a need to complete a systematic evaluation index system for golf course user preferences through future studies for a more detailed assessment, as well as a process to verify these evaluation indicators by application to domestic and international golf courses.

The Influence of Environmental Characteristics on the Fatness of Pacific Oyster, Crassostrea gigas, in Hansan-Koje Bay (한산${\cdot}$거제만의 환경특성이 양식 굴의 비만에 미치는 영향)

  • CHOI Woo-Jeung;CHUN Yong-Yull;PARK Jeung-Hum;PARK Yeong-Chull
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.5
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    • pp.794-803
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    • 1997
  • Long line suspended culture of oysters has been started commercially in Hansan-Koje Bay since 1969. However, its Annual production has been decreased and culturing periods extended in recent years. So, we investigated environmental parameters and food organisms to identity the causes of poor fatness of oysters in Hansan-Koje Bay from February to November, 1994. As the result, the Water quality of Hansan-Koje Bay was found to be good for culture. For example, the mean concentration of COD was $1.35mg/\ell$, phosphate phosphorus was $0.30{\mu}g-at/\ell$ and dissolved inorganic nitrogen was $4.68{\mu}g-at/\ell$. However, the Hwado island and the inner part of the Hansan-Koje Bay were found to be eutrophicated due to various contaminants transported by land-based activities. But in the central pan of the Hansan-Koje Bay where the oyster farms Have been developed densely, the level of nutrient concentration was very low. During the study period, the dominant species of phytoplankton was Chaetoceros spp. with the percentage of $72.6\%\~87.8\%$ and the mean values of Chlorophyll-a concentration and phytoplankton standing crops were $2.05mg/m^3\;and\;188ind./m\ell$, respectively. The distribution of these parameters also showed similar trends those of nutrients. Especially, chlorophyll-a contents was very low with the concentration of below $0.5mg/m^3$ at central part of the Bay, Juklimpo. The fatness of oysters and the eutrophic index in this area were $18.1\%$ and 0.54, respectively. These values were lower than those of other culturing farms in the southern coastal areas in Korea. Therefore, we estimated that the insufficient food supply due to the low level of nutritional status was the major factors affecting the poor fatness of the Pacific oysters in Hansan-Koje Bay.

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Effects of Supplementary Herbs and Plant Extracts on the Performance of Broiler Chicks (생약제(Herbs, Plant Extracts)의 급여가 육계의 생산성에 미치는 영향)

  • Woo, K.C.;Kim, C.H.;NamGung, Y.;Paik, I.K.
    • Korean Journal of Poultry Science
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    • v.34 no.1
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    • pp.43-52
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    • 2007
  • Experiments were conducted to investigate the effects of dietary botanicals (herbs and plant extracts) on the performance, nutrient metabolizability, small intestinal microflora, IgG level and blood parameters in broiler chickens. In Exp. 1, 1,000 (500 each sex) broiler chicks($Ross^{(R)}$) were divided into 20 groups of 50 chickens each(25 birds each sex). Four groups were assigned to each of five dietary treatments:control and diets containing antibiotics($Avillamix^{(R)}$, avillamycin-premix), Herb M(Herb $mix^{(R)}$), Plant extract B(BIOSTRONG $510^{(R)}$) and Plant extract A($APEX^{(R)}$). In Exp. 2, 240(120 each sex) broiler chicks($Ross^{(R)}$) were devided into six treatment groups:control and diets containing antibiotics($Avillamix^{(R)}$, avillamycin-premix), Plant extract D($Digestarom^{(R)}$), Plant extract P($Phellozyme^{(R)}$), Plant extract G($Galicin^{(R)}$) and Plant extract C(CRINA $POULTRY^{(R)}$). Each treatment consisted of four replicates of 10 birds each. In both experiments, birds had free access to diets and water for 5 wk on floor pens(Exp. 1) and cages(Exp. 2). In Exp.1, production index of groups fed diets supplemented with herbs and plant extracts was slightly higher than the control and those fed Herb M was highest. In Exp. 2, groups fed diets supplemented with herbs and plant extracts consumed more feed than the control during the period between 4 and 5 wk(P<0.05). Feed conversion(feed/gain) was lower in antibiotics group than other groups. The values of RBC, Hb and HCT were higher(P<0.05) in chicken fed diets supplemented with the additives than in the control in Exp. 1. BA value was lower(P<0.05) in groups fed diets supplemented with the additives than in the control in Exp. 2. Serum IgG were higher(P<0.05) in groups fed diets supplemented with the additives than in the control in both experiments. The cfu of intestinal microflora and metabolizability of nutrients were not significantly different among treatments in both experiments. It was concluded that the botanical supplements can be used as an alternative to antibiotics in broiler diets.

Changes of Benthic Macroinvertebrate Communities after a Small Dam Removal from the Gyeongan Stream in Gyeonggi-do, Korea (경기도 경안천에서 소형 보(洑)의 철거 이후에 변화된 저서성 대형무척추동물 군집)

  • Kil, Hye-Kyung;Kim, Dong-Gun;Jung, Sang-Woo;Shin, Il-Kwon;Cho, Kang-Hyun;Woo, Hyo-Seop;Bae, Yeon-Jae
    • Korean Journal of Environmental Biology
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    • v.25 no.4
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    • pp.385-393
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    • 2007
  • Benthic macroinvertebrate communities were studied after a small dam removal from the mid-section of the Gyeongan stream in Gyeonggi-do, Korea. Quantitative sampling was conducted at immediately upstream (upper) and downstream (lower) sites from the dam as well as at the site where the dam was located (dam site: middle) using a Surber sampler (50$\times$50 cm, mesh 0.25 mm), four times (November 2004, May 2005, January 2006, and May 2006) after the dam removal. As a result, 46 species of benthic macroinvertebtates, belonged in 35 genera, 27 families, 11 orders, 5 classes, and 4 phyla, were sampled from the stream sites, but the number of species that occurred at each sampling trial was different (ranged 3$\sim$17 spp.) according to the seasons and sites. Approximately one year after the dam removal, the species number has in-creased and taxa composition has changed as the microhabitat became more heterogeneously due to a riffle formation in the upstream site. Chironomid larvae and tubificid worms, which are common in Korean urban streams, were the dominant species, while Hydropsyche kozhantschikovi was the 2nd dominant species at some sampling trials. In general, McNaughton's dominance indices decreased and Shannon species diversity indices increased approximately one year after the dam removal. Compositions of collector-filterers, clingers, and swimmers increased as hydropsychid caddisflies, heptageniid mayflies, and baetid mayflies increased, respectively, in the upstream site. The group pollution index and the ecological score using benthic macroinvertebrates both indicated that water environment has been improved in the upstream site after the dam removal.

Feeding Effect of Whole Crop Rice based TMR on Meat Quality of Hanwoo Steers (사료용 벼 위주 TMR 급여가 거세 한우의 육질 특성에 미치는 영향)

  • Kim, Jong Geun;Jo, Cheroun;Zhao, Guo Qiang;Liu, Chang;Nan, Wei Sheng;Kim, Hak Jin;Ahn, Eok Geun;Min, Hyung-Gyu
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.39 no.4
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    • pp.264-271
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    • 2019
  • This study was conducted to investigate the effect of whole crop rice based TMR on the meat quality of Korean Native Cattle (Hanwoo). Sixteen Hanwoo steers (average 8 months old) were divided into the control group (commercially marketed TMR) and the WCR-TMR group (whole crop rice based TMR). Feeding trials were carried out up to 30 months of age, and after slaughter, the strip loin were collected and analyzed for meat quality. There were no significant differences in proximate compositions of Hanwoo (P>0.05), and crude protein, crude fat and crude ash were 19.51~20.23 %, 11.53~11.35 % and 1.10~1.12 %, respectively. There was no significant difference in water holding capacity and cooking loss between treatments (P>0.05), but it was slightly lower in the control group. Among the various functional components in meat, β-carotene was not detected, but α-tocopherol was significantly higher in WCR-TMR group and vitamin A content in control (P<0.05). The a-value in the meat color index decreased significantly with longer storage period in the control group, whereas the WCR-TMR fed group showed no significant difference (P>0.05) according to the storage period. There were no difference between the treatments in the TBARS (2-Thiobarbituric acid reactive substances) value used as an indicator of lipid oxidation and in fatty acid content. But the control group had high myristic acid content, whereas the WCR-TMR supplemented group showed higher oleic acid and linoleic acid content. In conclusion, feeding of WCR based-TMR increased the α-tocopherol content, which is a functional ingredient in meat, and the other components were not significantly different from the control. Therefore, it was judged that there was no significant difference between WCR based and conventional TMR in meat quality characteristics.

Modulation of Immune Parameters by Aging Process (노화에 따른 면역지표의 변화에 관한 연구)

  • Lee, Ji-Hye;Jung, Ji-Hye;Kim, Hyun-Sook
    • Journal of Nutrition and Health
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    • v.43 no.2
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    • pp.152-160
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    • 2010
  • The purpose of this study was to investigate the effects of aging process on the immunity in human subjects. In this investigation, nineteen families of three generations (daughters on college age, their mothers, and grandmothers) participated to avoid genetic variation among individuals. Dietary food records, anthropometric measurements and biochemical assessments of serum nutrients were used to evaluate the nutritional status of subjects. The immune parameters of subjects were assessed by the total and differential WBC count. Total B and T lymphocytes, and T cell subsets were quantified by flowcytometer. Serum immunoglobulin G, A, M concentrations were also measured as an index of humoral immunity. The result of this study can be summarized as follows: 1. Along with the aging process, body fat was found to be increased whereas lean body mass and total body water were diminished. Since there were no significant difference in serum vitamin E levels in all age groups, serum retinal concentrations tended to decrease as one gets old. 2. Although total number of T lymphocytes seemed to be unchanged, B lymphocytes and NK cell numbers were increased by aging. The Percentage of CD8 + lymphocytes was lower in the elderly subjects compared with the younger, resulting in higher ratio of CD4 +/CD8 + lymphocytes in the elderly. Serum Ig G and Ig A levels remained unchanged, but IgM levels were significantly decreased as the age processes continue. Taking all together, it could be suggested that the alteration of immune cell population by aging is selective and possibly nonage factors such as nutrition may be attributable to the change of immunity in the elderly. The nutritional status and aging process may selectively affect both the cell-mediated (CD8 +, CD4 + CD8 + ratio, NK cell) and humoral (B lymphocyte, Immunoglobulin M, G) immune parameters in human subjects.

Assessment of Particle Size Distribution and Pollution Impact of Heavy metalsin Road-deposited Sediments(RDS) from Shihwa Industrial Complex (시화산업단지 도로축적퇴적물의 입도분포 및 중금속 오염영향 평가)

  • Lee, Jihyun;Jeong, Hyeryeong;Ra, Kongtae;Choi, Jin Young
    • Journal of Environmental Impact Assessment
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    • v.29 no.1
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    • pp.8-25
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    • 2020
  • Industrialization has increased the production of road-deposited sediments (RDS) and the level of heavy metals in those RDS, which can have a significant impact on the surrounding aquatic environments through non-point pollution. Although the relationship between contamination characteristics and particle size of RDS is important for pollution control, there is very little information on this. In this study, we investigated the characteristics of grain size distribution and heavy metal concentrations in the road-deposited sediments (RDS) collected from 25 stations in Shihwa Industrial Complex. The environmental impact of RDS with particle size is also studied. Igeo, the contamination assessment index of each metal concentration, represents the RDS from Shihwa Industrial Complex are very highly polluted with Cu, Zn, Pb and Sb, and the levels of those metals were 633~3605, 130~1483, 120~1997, 5.5~50 mg/kg, respectively. The concentrations of heavy metals in RDS increased with the decrease in particle size. The particle size fraction below 250 ㎛ was very dominant with mass and contamination loads, 78.6 and 70.4%, respectively. Particles less than 125 ㎛ of RDS were highly contaminated and toxic to benthic organisms in rivers. RDS particles larger than 250 ㎛ and smaller than 250 ㎛ were contaminated by the surrounding industrial facility and vehicle activities, respectively. As a result of this study, the clean-up of fine particles of RDS, smaller than 125-250 ㎛, is very important for the control and reduction of non-point pollution to nearby water in Shihwa Industrial Complex.

Studies on the Reproductive Cycle of Damselfish, Chromis notatus (Temminck et Schlegel) (자리돔의 생식주기에 관한 연구)

  • LEE Young Don;LEE Taek Yuil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.20 no.6
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    • pp.509-519
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    • 1987
  • Annual reproductive cycle of the Damselfish, Chromis notatus collected monthly at the four coastal areas around Chejudo, Korea are studied on the bases of histological observations of gonadal tissue and various quantitative variables including gonadosomatic index (GSI), fatness, egg diameter composition and the first maturity. The ovary consisted of a pair of saccular structure with many ovarian sacs. Oogonia proliferated along the germinal epithelium of the ovarian sac. Young oocytes with basophilic cytoplasm showed several nucleoli along the nuclear membrane. When the oocytes reached about $450{\mu}m$ in diameter, nucleus migrate toward the animal pole, nuclear membrane disappeared and most of cytoplasm were filled with yolk materials and oil drops. After ovulation, residual follicle and growing oocytes remaining in the ovarian sacs degenerated. But early young oocytes without follicle layer were not degenerated, and growing continuously till the next year. The testis consisted of a pair of lobular structures in the right and left were united in the posterior seminal vesicle. Cortex of testis was composed of many sperm ducts connected with lobuli. GSI began to increase from March, starting season of longer day length and higher water temperature, and reached the maximum value between June and August. It began to decrease from September with the lowest value appearing between October and February without any evident variation. The annual reproductive cycle could be devided into five successive stage : growing(April to Many), mature(May to August), ripe and spent (June to August) and recovery and resting stage(September to March). The spawning peak occurred from June to August. According to the frequency distribution of egg diameter, Chromis notatus was a polycyclic species to spawn twice or more in a spawning season. Fatness, correlated with gonadal phases, was remarkably decreased by spawning. Percentage of the first maturity . in femate and male fish ranging from 7.0 to 7.9 cm were $50\%$ and from 9.0 to 9.9 cm in total length $100\%$.

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Analgesic Effect of Hippophae rhamnoides Extract in Orofacial Pain in Rats (구강안면통증모델에서 산자나무 추출물의 진통효과)

  • Kim, Yun-Kyung;Choi, Ja-Hyeong;Kim, Hee-Jin;Yoon, Hyun-Seo;Hyun, Kyung-Yae;Lee, Min-Kyung
    • Journal of dental hygiene science
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    • v.17 no.6
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    • pp.495-500
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    • 2017
  • Hippophae rhamnoides L. (sea buckthorn) is a shrub wood that belongs to the bamboo tree family, and is rich in vitamin C, D, and E; it is referred to as a vitamin tree. It is mainly grown in the high mountains of Europe and Central Asia, and has been widely used in China and Russia as natural medicine. Recent studies have shown that it is effective in the treatment of cancer, liver diseases, cardiovascular diseases, and gastrointestinal diseases. However, results of studies on its effect on the regulation of pain are insufficient. In this study, we investigated the effect of sea buckthorn on the development and control of pain in two facial areas. The experimental animals included 7- to 8-week-old Sprague-Dawley rats (240~260 g). Formalin (5%), which is known as an inflammation inducer, was injected into the vibrissa pad or temporomandibular joints to induce orofacial acute pain. Rubbing or scraping of the region injected with formalin was regarded as a pain index, and the behavioral response was observed for 45 minutes after the injection. Sea buckthorn extract diluted to 150, 300 mg/kg (in 1 ml of distilled water) was orally administered 30 minutes prior to the acute pain. The facial pain behavior was effectively reduced in the 300 mg/kg group when compared to the control group (vehicle). Likewise, in an experiment in which formalin was injected into the temporomandibular joints, effective pain alleviation was confirmed at the same drug concentration. These results suggest that sea buckthorn extract may be useful in the development of therapeutic agents for acute inflammatory pain in the orofacial area and for controlling temporomandibular joint pain.