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Monitoring of Heavy Metals in Fruits in Korea (유통 중인 과일류의 중금속 모니터링)

  • Lee, Jin-Ha;Seo, Ji-Woo;An, Eun-Sook;Kuk, Ju-Hee;Park, Ji-Won;Bae, Min-Seok;Park, Sang-Wook;Yoo, Myung-Sang
    • Korean Journal of Food Science and Technology
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    • v.43 no.2
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    • pp.230-234
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    • 2011
  • According to the Codex committee, the maximum allowable level for lead in fruits is 0.1 mg/kg. This survey was conducted as a surveillance program following the establishment of safety guideline for fruits in Korea. Concentrations of lead (Pb), cadmium (Cd), arsenic (As) and mercury (Hg) were measured in 927 samples using a ICP-MS and a mercury analyzer. The recoveries of microwave digestion method were 86.0-110.4% for Pb, 81.0-104.0% for Cd and 82.0-104.7% for As by standard addition method. The recovery of direct mercury analyzer was 106.5% for Hg. The average levels of Pb in ${\mu}g/kg$ were $10.0{\pm}12.8$ for apple, $8.8{\pm}10.9$ for pear, $4.1{\pm}4.4$ for persimmons, $14.9{\pm}12.3$ for mandarin, $7.1{\pm}6.5$ for orange, $3.1{\pm}3.3$ for banana, $8.8{\pm}8.9$ for kiwi, and $9.3{\pm}9.7$ for mango. The average levels of Cd in ${\mu}g/kg$ were $0.4{\pm}0.3$ for apple, $2.0{\pm}1.6$ for pear, $0.3{\pm}0.3$ for persimmon, $0.1{\pm}0.1$ for mandarin, $0.1{\pm}0.1$ for orange, $1.3{\pm}1.8$ for banana, $0.5{\pm}0.5$ for kiwi, and $0.7{\pm}0.6$ for mango. The average levels of As in ${\mu}g/kg$ were $2.0{\pm}2.1$ for apple, $1.2{\pm}1.3$ for pear, $1.5{\pm}1.2$ for persimmon, $0.8{\pm}0.3$ for mandarin, $1.5{\pm}0.5$ for orange, $1.8{\pm}1.2$ for banana, $1.6{\pm}1.5$ for kiwi, and $1.2{\pm}1.5$ for mango. The average levels of Hg in ${\mu}g/kg$ were $0.5{\pm}0.4$ for apple, $0.3{\pm}0.2$ for pear, $0.2{\pm}0.1$ for persimmon, $0.2{\pm}0.1$ for mandarin, $0.2{\pm}0.1$ for orange, $0.2{\pm}0.0$ for banana, $0.2{\pm}0.2$ for kiwi, and $0.6{\pm}0.2$ for mango. Based on the Korean public nutrition report 2005, these levels (or amounts) are calculated only at 0.17% for Pb, 0.013% for Cd and 0.006% for Hg of those presented in provisional tolerable weekly Intake (PTWI) which has been established by FAO/WHO. Therefore, the levels presented here are presumed to be adequately safe.

Survey on Sodium Contents in Meals of School Foodservice and Sodium Intakes of Students in Busan and Gyeongsangbuk-do (부산.경북지역 초.중학교 급식메뉴의 나트륨 함량 및 학생들의 나트륨 섭취 실태 조사)

  • Lee, Hwee-Jae;Lee, Chang-Hee;Lee, Kwang-Su;Jung, Young-Ji;Ha, Sook-Hee;Jung, Yoo-Young;Kim, Dong-Sul
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.1
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    • pp.85-91
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    • 2010
  • Sodium is a major component that maintains homeostasis and physiological state in body. It is an essential mineral that the body cannot produce for itself, so it must be supplied from food. On the other hand, overindulgence is one cause of hypertension, stroke, stomach cancer, osteoporosis and kidney disease. The purpose of this study was to monitor sodium content in meals of school foodservice. In this study, 801 samples (main/side dishes) were collected from 8 school foodservice in Busan and Gyeongsangbuk-do, Korea. Samples were classified into 21 food items, which were cooked rices, cooked rice with seasoning, noodles, cooked gruels, soups, stews, tang and chon-gol, stir-fried foods, fried foods, pan-fried foods, hard-boiled foods, roasted foods, steamed foods, seasoned vegetables, preserved foods, kimchis, sauces, fruits, breads and snacks, beverages, and dairy products. The samples were analyzed by AAS (atomic absorption spectrometry) after microwave digestion. The sodium content of sauces (1459 mg/100 g) and preserved foods (1165 mg/100 g) was higher than those of other dishes. Aside from them, sodium contents of roasted foods (894 mg/100 g), hard-boiled foods (786 mg/100 g) and kimchis (737 mg/100 g) were relatively higher than the others. Sodium intakes from meals of school foodservice were calculated by multiplying food intakes by sodium contents. The average sodium intakes from one serving of school foodservice were 605 mg for younger boys, 572 mg for younger girls, 774 mg for older boys, 730 mg for older girls in elementary school. Boys in middle school took in 1423 mg Na whereas girls consumed 1063 mg Na in middle school. Results from this study can be useful for establishing database of sodium contents and intake in meals of school foodservice. The database will be helpful for providing information on managing food for children.

Physicochemical Characteristics and Varietal Improvement Related to Palatability of Cooked Rice or Suitability to Food Processing in Rice (쌀 식미 및 가공적성에 관련된 이화학적 특성)

  • 최해춘
    • Proceedings of the Korean Journal of Food and Nutrition Conference
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    • 2001.12a
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    • pp.39-74
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    • 2001
  • The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s∼1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great, progress and success was obtained in development of high-quality japonica cultivars and qualify evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice caltivars and special rices adaptable for food processing such as large kernel, chalky endosperm aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and torture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak. hot paste and consistency viscosities of viscogram with year difference. The high-quality rice variety “Ilpumbyeo” showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic mcroscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high Probability of determination. The ${\alpha}$ -amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, shelved the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogiadation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice bread. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large gram rices showed better suitability for fermentation and brewing. Our breeding efforts on rice quality improvement for the future should focus on enhancement of palatability of cooked rice and marketing qualify as well as the diversification in morphological and physicochemical characteristics of rice grain for various value-added rice food processings.

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A Study of Home Care Needs of Patients at Discharge and Effects of Home Care -Centered on Patients Discharged from a Rural General Hospilal- (퇴원환자의 가정간호요구와 가정간호사업의 효과 분석 - 일 종합병원을 중심으로)

  • Choi, Yun Soon;Kim, Dai Hyun;Storey, Margaret;Kim, Cho Ja;Kang, Kyu Sook
    • The Korean Nurse
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    • v.31 no.4
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    • pp.77-99
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    • 1992
  • The study was carried out at W. hospital, an affiliated hospital of Y university, involved a total of 163 patients who were discharged from the hospital between May 1990 und March 199J. Data collection was twice, just prior to discharge and a minimum of three months post discharge. Thirty patients who lived within a hour travel time of the hospital received home care during the three months post discharge. Nursing diagnoses and nursing interventions For these patients were analyzed in this study. The results of the study are summarized as follows : 1. Discharge needs for the subjects of the study were analyzed using Gordon's eleven Functional categories and it was found that 48.3% of the total sample had identified nursing needs. Of these, the needs most frequently identified were in the categories of sexuality, 79.3 %, health perception, 68.2 % self concept, 62.5 %, and sleep and rest 62.5 %. Looking ut j he nursing diagnosis that were made for the 30 patients receiving home care, the following diagnoses were the most frequently given; alteration in sexual pattern 79.3%, alterations in health maintenance, 72.6%, alteration in comfort, 68.0%, depression, 64.0%, noncompliance with diet therapy, 6.3.7%, alteration in self concept, 55.6%, and alteration in sleep pattern, 53%. 2. In looking at the effects of home nursing care as demonstrated by changes in the functional categories over the three month period, it was Found that of the 11 functional categories, the need level for health perception, nutrition, activity and self concept decreased slightly over the three month period. On the average sleep patterns improved, but restfulness was slightly less and bowel elimination patterns improved but satisfaction with urinary elimination was slightly less. On the other hand, role enactment, sexuality, stress management and spirituality decreased slightly. The only results that were statistically significant at the 0.05 level were improvement. in digestion and decrease in pain. No statistically significant changes were found in ability related to ADL, the total ADL Score at discharge was $19.78{\pm}8.234, and after 3 months $19.01{\pm}8.12$. Considering that a majority of the patients were over 60 years of age and that many had brain or spinal cord injuries, the fact that their ADL ability did nor deteriorate after discharge can be interpreted as related to a positive impact by the home health care nurses. Similarly there was a slight be not statistically significant decrease in the quality of life scores between the two lest times(l47.83 at discharge and 113.02 at the three month period). Again, when the chronic nature of thee problems facing these patients is considered this maintenance of quality of life can be interpreted as a positive impact by the home health care nurses. 3. One of the home care nursing activities was diagnosis. For this activity it was found that for nine functional health categories(sexuality and spirituality excepted) there were 20 nursing diagnoses. The most frequent were noncompliance, alteration in skin integrity both actual and potential, and impaired physical mobility in that order. 4. Delivery of home health care by the home health nurses included the following nursing activities; assessment, patient education, demonstration of care activities, counselling, direct care to the patient and referrals. Direct care included changing dressings, bladder irrigations, changing Foley catheters, measurement of residual urine, perineal care, position change, back care, oral hygiene, exercise and massage of motion exercises, cleansing enemas, tracheostomy suctioning and tracheostomy care, care of dentures, applications of heat and other similar nursing activities. In conclusion almost 50% of (he sample indicated a need for continued nursing care at the time of discharge and for the patients in the sample who received home care there was a slight decrease in nursing needs but while the patients had chronic and debilitation problems there was ill decrease in ADL abilities or in quality of life. Further study needs Lo be done La increase the reliability and validity of the tool that was used to measure home health care needs. It is also recommended that study by done using a randomized sampling with a control group to compare patients who receive home care with those who do not.

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Digestibility of Infant Food and its Nutritional Meaning (유아식품(乳兒食品)의 소화율(消化率)과 영양적(營養的) 의의(意義))

  • Hong, Ki-Wook;Yoo, Jai-Ja
    • Journal of Nutrition and Health
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    • v.7 no.1
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    • pp.17-23
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    • 1974
  • Digestibilities of flour of white wheat, barley, potato, sweet potato, are $5{\sim}11$ percent (3hrs.) in unripe starch state and in gelatinization, digestibilities are up to $20{\sim}30$ percent (3hrs.). And in two states, digestibilities of flour of potato and sweet potato are lower than barley and white wheat flour. If it is not gelatinization, digestibilities of biscuit and cracker are much lower than popped cake (29%). In gelatinization, digestibilities of biscuit and cracker $(19{\sim}29%,\;3hrs.)$ are similar to gelatinized flour of materials. Digestibilities of bread and castern is $21{\sim}32$ percent, it is similar to gelatinized flour of materials. And bread is higher than castera. Digestibility of on the marketing weaning food (II) (15%, 3hrs.) is much lower than food (I) (24.1%, 3hrs.) When the date of manufacturing passed $1{\sim}2$ months, digestibility of some cookies have a tendency to low. When mothers choice the infant weaning food, they consider metritional value (42%) and digestibility (27%). Also when they make weaning food at home, they generally use flour of rice (41%) and white wheat (23%). And they think, the rate of digestion is 49% in the rice flour and white wheat (23%). It was sort of cooked of rice (16%) and weaning food on the marketing(13%), which accepts to good digest. Also it was sort of biscuits (44%) which comparatively high choice snack food.

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Identification of Novel Single Nucleotide Polymorphisms on ADSL Gene Using Economic Traits in Korean Native Chicken (한국재래닭의 ADSL 유전자 내 단일염기변이를 이용한 경제형질과의 연관성 분석)

  • Lee, J.A.;Jeon, S.A.;Oh, J.D.;Park, K.D.;Choi, K.D.;Jeon, G.J.;Lee, H.K.;Kong, H.S.
    • Korean Journal of Poultry Science
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    • v.36 no.3
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    • pp.207-213
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    • 2009
  • Adenylosuccinate lyase (ADSL) deficiency is a disease of purine metabolism which affects patients both biochemicall and behaviorally. An obstacle of this purine nucleotide cycle(PNC) can be caused brain functional disorder and growth disorder. So ADSL deficiency, which is associated with sever mental retardation, autistic features and energy metabolism. This study was performed to identify SNP on ADSL gene in chicken. The nucleotides were observed as T to C ($7724^{th}$ nucleotide), C to T ($7732^{nd}$ nucleotide), G to T ($10108^{th}$ nucleotide), A to T ($10356^{th}$ nucleotide), G to A($10375^{th}$ nucleotide), A to C ($10402^{nd}$ nucleotide), A to T ($12716^{th}$ nucleotide), T to A ($12717^{th}$ nucleotide), C to T ($15491^{st}$ nucleotide), C to T ($15542^{nd}$ nucleotide) and C to T ($15550^{th}$ nucleotide). The nucleotide substitutions at $15542^{nd}$ and $15550^{th}$ (GeneBank accession no. AY665559) were found as missense mutation (alanine$\rightarrow$valine, proline$\rightarrow$serine, respectively). This study will be useful for farther researches for identifying association between these SNPs and energy metabolism in chicken. The C15550T SNP showed three genotypes, CC, CT, TT by digestion with the genotype TT had significantly faster the first lay day (150.0) than CT (162.0, P<0.05) and genotype TT (150.0, P<0.05) had significantly higher the egg production rate than CT (172.4, P<0.05). According to result of this study, a C15550T was found to have a significantly effect first lay day and mean egg production. It will be possible to use SNP marker on selecting chicken to improve important economic traits, which is the first lay day and mean egg production.

Effect of Substrate to Inoculum Ratio on Biochemical Methane Potential in the Thermal Pretreatment of Piggery Sludge (양돈분뇨의 열전처리에서 기질과 접종액의 비율이 메탄생산 퍼텐셜에 미치는 영향)

  • Kim, Seung-Hwan;Kim, Ho;Oh, Seong-Yong;Kim, Chang-Hyun;Yoon, Young-Man
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.4
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    • pp.532-539
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    • 2012
  • This study was carried out to investigate the effect of substrate to inoculum ratio on ultimate methane potential ($B_u$) from piggery wastes. BMP(Biochemical methane potential) assays were executed for the three samples that have different organic characteristics (Filtrate of pig slurry, LF; Thermal hydrolysate of piggery sludge cake, TH; Mixture of LF and TH at the ratio of 4 to 1, Mix), and $B_u$ values obtained from BMP assays were compared with the theoretical methane potential ($B_{th}$) of each samples. While $B_u$ values (0.27, 0.44, and $0.46Nm^3\;Kg^{-1}-VS_{added}$) of TH sample that was pretreated with thermal hydrolysis were below the $B_{th}$ at all S/I ratios (0.1, 0.3, and 0.5), and $B_u$ values of LF (0.64 and $0.53Nm^3\;Kg^{-1}-VS_{added}$ for the S/I ratios of 0.1 and 0.3, respectively) at the lower S/I ratios of 0.1 and 0.3 exceeded the $B_{th}$ values ($0.418Nm^3\;Kg^{-1}-VS_{added}$). And also biodegradability ($B_u/B_{th}$) of LF sample were obtained as 152.07%, 122.67%, and 95.71% at the S/I ratios of 0.1, 0.3, and 0.5, respectively, and unreasonable $B_u/B_{th}$ values were presented at lower S/I ratios of 0.1 and 0.3. $B_u$ and $B_u/B_{th}$ of Mix sample showed a similar tendency with those of LF sample. Therefore, TH sample by thermal hydrolysis pretreatment showed lower anaerobic biodegradability than those of other samples (LF and Mix) and ultimate methane potentials of LF and Mix samples were overestimated in the lower S/I ratio of 0.1 and 0.3.

Effect of the Pretreatment by Thermal Hydrolysis on Biochemical Methane Potential of Piggery Sludge (열가수분해 전처리가 양돈 슬러지의 메탄생산퍼텐셜에 미치는 영향)

  • Kim, Seung-Hwan;Kim, Ho;Kim, Chang-Hyun;Yoon, Young-Man
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.4
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    • pp.524-531
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    • 2012
  • The objective of this study was to investigate the organic solubilization (SCOD) and improvement of methane production for pig slurry by thermal hydrolysis. A sludge cake was pretreated by thermal hydrolysis at different reaction temperatures (200, 220, 250, $270^{\circ}C$). Ultimate methane potential (Bu) was determined at several substrate and inoculum (S/I) ratios (1:9, 3:7, 5:5, 7:3 in volume ratio) by biochemical methane potential (BMP) assay for 73 days. Pig slurry SCOD were obtained with 98.4~98.9% at the reaction temperature of $200{\sim}270^{\circ}C$. Theoretical methane potentials ($B_{th}$) of thermal hydrolysates at the reaction temperature of $200^{\circ}C$, $220^{\circ}C$, $250^{\circ}C$, $270^{\circ}C$ were 0.631, 0.634, 0.705, $0.748Nm^3\;kg^{-1}-VS_{added}$, respectively. $B_u$ of $200^{\circ}C$ thermal hydrolysate were decreased from $0.197Nm^3\;kg^{-1}-VS_{added}$ to $0.111Nm^3\;kg^{-1}-VS_{added}$ with the changes of S/I ratio from 1:9 to 7:3, and also $B_u$ of different thermal hydrolysates ($220^{\circ}C$, $250^{\circ}C$, $270^{\circ}C$) showed same tendency to $B_u$ of $200^{\circ}C$ thermal hydrolysate according to the changes of S/I ratio. Anaerobic biodegradability ($B_u/B_{th}$) of $200^{\circ}C$ thermal hydrolysate at different S/I ratios was decreased from 32.2% for S/I ratio of 1:9 to 17.6% for S/I ratio of 7:3. $B_u/B_{th}$ of $220^{\circ}C$, $250^{\circ}C$, and $270^{\circ}C$ thermal hydrolysat were decreased from 36.4% to 9.6%, from 31.3% to 0.8%, and from 26.6% to 0.8%, respectively, with the S/I ratio change, respectively. In this study, the rise of thermal reaction temperature caused the decrease of anaerobic digestibility and methane production while organic materials of pig slurry were more solubilized.

Correction Method of Anaerobic Organic Biodegradability by Batch Anaerobic Digestion (회분식 혐기소화에 의한 혐기적 유기물 분해율의 보정 방법)

  • Kim, Seung-Hwan;Oh, Seung-Yong;Kim, Chang-Hyun;Yoon, Young-Man
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.1086-1093
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    • 2012
  • This research was carried out to develop the correction method of VDI4630 method improving accuracy, and investigated the effects of carbonate ion ($CO_3{^{2-}}$) and reactant water ($H_2O$) on anaerobic organic biodegradability in VDI4630 method. Pig blood, pig intestine residue, pig digestive tract content, and cattle rumen content were experimented as waste biomasses. Chemical formulas of pig blood, pig intestine residue, pig digestive tract content, and cattle rumen content were $C_{3.78}H_{8.39}O_{1.46}N_1S_{0.01}$, $C_{9.69}H_{15.42}O_{2.85}N_1S_{0.03}$, $C_{25.17}H_{43.32}O_{15.04}N_1$, $C_{27.23}H_{42.38}O_{15.93}N_1S_{0.11}$, respectively. And amount of reactant moisture for the anaerobic degradation of organic materials were 0.336, 0.485, 0.227, 0.266 mol, respectively. In pig blood, pig intestine residue, pig digestive tract content, and cattle rumen content, anaerobic organic biodegradability presented as $B_u/B_{th}$ were 82.3, 81.5, 70.8, and 66.1%, and anaerobic organic biodegradability (AB) by VDI4630 method were 72.2, 87.8, 74.2, 62.0%, and that were significantly different with anaerobic organic biodegradability presented as $B_u/B_{th}$. The effects of carbonate ion and reactant water on anaerobic organic biodegradability were not significant, But Accuracy of anaerobic organic degradability was expected to able to be improved by the correction method of VDI4630 considering the carbonate ion at digestate and the reactant water quantified.

Seasonal Variations of Metacercarial DEnsity of Clonorchis sinensis in Fish Intermediate Host, Pseudorasbora parva (간흡충 유행지역에서 참붕어내 피낭유충 감염밀도의 계절적 변동)

  • Gang, Sin-Yeong;Kim, Seok-Il;Jo, Seung-Yeol
    • Parasites, Hosts and Diseases
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    • v.23 no.1
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    • pp.87-94
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    • 1985
  • The seasonal variations of the rate and intensity of metacercarial infection of C. sinensis in P. parva were observed. The fish were collected at Sun-Am River which located in Kim-Hae City, Kyong-Sang Nam Do (=Province), Korea, from March 1983, to February 1984 every month. A total of 788 fish was examined. The number of metacercariae in each fish was individually counted after the individual digestion by artificial gastric juice. The results were as follows: 1. During one year, 513 (65.1%) out of 788 fish were infected with metacercariae. In May, June, July and September, the infection rates ranged from 82.0% to 98.6% whereas the rates was relatively low in March, April, November and February ranging from 11.4% to 64.7%. 2. The intensity of infection was similar with those of infection rates. The mean intensity per infected fish was 103.0 and standard deviation was 118.9 throughout one year. The highest mean intensity was in June (294.8) and the lowest in November (11.1). 3. The observed frequency of fish with certain intensities of metacercariae were fitted to theoretical equations derived from negative binomial distribution in March, April, November and February (p>0.05). Meanwhile, the equation of lognormal distribution were fitted with the observed frequencies in May, June, July and September (p>0.05, p>O. 75). The variance/mean ratio varied by month. The value was the highest in July (814.3) and the lowest in November (158.8). Unlike our hypothesis, the metacercarial density of Clonorchis sinensis in its the most favorable fish host, Pseudorasbora parva showed considerable seasonal variations in the hyperendemic area. The possible factors were discussed.

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