• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.1
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• pp.11-24
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• 1979

To characterize elastic and plastic chilling injury, rice seedlings grown at 28/$16^{\circ}C$ day/night temp. under 20K lux (13hrs.) in a phytotron were subjected to a 11/$6^{\circ}C$, 20K lux condition for 2, 4, 6 or 8 days at 1, 2, 3, 4 or 5th leaf-stage, respectively, followed by further growth under 28/$16^{\circ}C$condition till 30th day after seeding. Japonica variety Jinheung and Chulwon No.1 survived almost 100% without any significant , discoloration and death of leaves due to chilling even under the chilling of 8 days at all seedling ages tested. Tongil and Yushin, varieties from Indica x Japonica cross, showed increasing discoloration of leaves and death of plants with increase in chilling intensity. The longest chilling duration shown seedling death less than 5% was 4, 6, 1, 4, 8 days for Tongil, and 6, 6, 1, 2, 2, days for Yushin at 1, 2, 3, 5th leaf-stage, respectively. The degree of discoloration and death of leaves or suppression of height growth was not explicitly related to seedling death or the dry weight reduction. The degree of seedling death or dry weight reduction could differentiate chilling tolerance of varieties and seedling ages, but somewhat differently. Reduction in dry weight due to chilling occurred even without any visible injury or seedling death. These suggest that both the degree of seedling death and reduction in dry weight should be considered in the test of varieties for chilling tolerance. Combined evaluation of seedling death and dry weight reduction indicated the most susceptible seedling age to chilling injury to be 1 to 2nd leaf-stage for Jinheung, 2 to 3rd leaf-stage for Chulwon No.1, 3rd leaf- stage for Tongil and Yushin, respectively.

• Radiation Oncology Journal
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• v.18 no.4
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• pp.257-264
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• 2000

Purpose: For early stage non-small-cell lung cancer, surgical resection is the treatment of choice. But when the patients are not able to tolerate it because of medical problem and when refuse surgery, radiation therapy is considered an acceptable alternative. We report on the treatment results and the effect of achieving local control of primary tumors on survival end points, and analyze factors that may influence survival and local control. Materials and Method : We reviewed the medical records of 32 patients with medically inoperable non-small cell lung cancer treated at our institution from June, 1987 through June, 1997. All patients had a pathologic diagnosis of non-small cell lung cancer and were not candidate for surgical resection because of either patients refusal (4), old age (2), lung problem (21), chest wail invasion (3) and heart problems (3). In 8 patients, there were more than 2 problems. The median age of the patients was 68 years (ranging from 60 to 86 years). Histologic cell type included souamous (24), adenocarcinoma (6) and unclassiried squamous cell (2). The clinical stages of the patients were 71 in 5, 72 in 25, 73 in 2 patients. Initial tumor size was 3.0 cm in 11, between 3.0 cm and 5.0 cm in 13 and more than 5.0 cm in 8 patients. Ail patients had taken chest x-rays, chest CT, abdomen USG and bone scan. Radiotherapy was delivered using 6 MV or 10 MV linear accelerators. The doses of primary tumor were the ranging from 54.0 Gy to 68.8 Gy (median; 61.2 Gy). The duration of treatment was from 37 days through 64 days (median; 0.5 days) and there was no treatment interruption except 1 patient due to poor general status. In 12 patients, concomitant boost technique was used. There were no neoadjuvant or adjuvant treatments such as surgery or chemotherapy. The period of follow-up was ranging from 2 months through 93 months (median; 23 months). Survival was measured from the date radiation therapy was initiated. Results : The overall survival rate was 44.6$\%$ at 2 years and 24.5$\%$ at 5 years, with the median survival time of 23 months. of the 25 deaths, 7 patients died of intercurrent illness, and cause-specific survival rate was 61.0$\%$ at 2 years and 33.5$\%$ at 5 years. The disease-free survival rate was 38.9$\%$ at 2 years and 28.3$\%$ at 5 years. The local-relapse-free survival rate was 35.1$\%$, 28.1$\%$, respectively. On univariate analysis, tumor size was significant variable of overall survival (p=0.0015, 95$\%$ C.1.; 1.4814-5.2815), disease-free survival (P=0.0022, 95$\%$ C.1., 1.4707-5.7780) and local-relapse-free survival (p=0.0015, 95$\%$ C.1., 1.2910- 4.1197). 7 stage was significant variable of overall survival (p=0.0395, 95$\%$ C.1.; 1.1084-55.9112) and had borderline significance on disease-free survival (p=0.0649, 95$\%$ C.1.; 0.8888-50.7123) and local-relapse-free survival (p=0.0582, 95$\%$ C,1.; 0.9342-52.7755). On multivariate analysis, tumor size had borderline significance on overall survival (p=0.6919, 955 C.1., 0.9610-5.1277) and local-relapse-free survival ( p=0.0585, 95$\%$ C.1.; 0.9720-4.9657). Tumor size was also significant variable of disease-free survival (p=0.0317, 95% C.1.; 1.1028-8.4968). Conclusion : Radical radiotherapy is an effective treatment for small (71 or f3 cm) tumors and can be offered as alternative to surgery in elderly or infirmed patients. But when the size of tumor is larger than 5 cm, there were few long-term survivors treated with radiotherapy alone. The use of hypefractionated radiotherapy, endobronchial boost, radisensitizer and conformal or IMRT should be consider to improve the local control rate and disease-specific survival rate.

• Journal of Food Hygiene and Safety
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• v.21 no.4
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• pp.231-237
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• 2006

Nowadays the teabag is worldwide used for various products including green tea, tea, coffee, etc. since it is convenient for use. In case of outer packaging printed, however, there is a possibility that the plasticizers which is used for improvement in adhesiveness of printing ink may shift to inner tea bag. In this study, in order to monitor residual levels of plasticizers in teabags, we have established the simultaneous analysis method of 9 phthalates and 7 adipates plasticizers using gas chromatography (GC). These compounds were also confirmed using gas chromatography-mass spectrometry (GC-MSD). The recoveries of plasticizers analyzed by GC ranged from 82.7% to 104.6% with coefficient of variation of $0.6\sim2.7%$ and the correlation coefficients of each plasticizer was $0.9991\sim0.9999$. Therefore this simultaneous analysis method was showed excellent reproducibility and linearity. And limit of detection (LOD) and limit of quantitation (LOQ) on individual plasticizer were $0.1\sim3.5\;ppm\;and\;0.3\sim11.5\;ppm$ respectively. When 143 commercial products of teabag were monitored, no plasticizers analysed were detected in filter of teabag products. The migration into $95^{\circ}C$ water as food was also examined and the 16 plasticizers are not detected. In addition we carried out analysis of heavy metals, lead (Pb), cadmium (Cd), arsenic (As) and aluminum (Al) in teabag filters using ICP/AES. $Trace\sim23{\mu}g$ Pb per teabag and $0.6\sim1718{\mu}g$ Al per teabag were detected in materials of samples and Cd and As are detected less than LOQ (0.05 ppm). The migration levels of Pb and Al from teabag filter to $95^{\circ}C$ water were upto $11.5{\mu}g\;and\;20.8{\mu}g$ per teabag, respectively and Cd and As were not detected in exudate water of all samples. Collectively, these results suggest that there is no safety concern from using teabag filter.

• Journal of Technologic Dentistry
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• v.10 no.1
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• pp.159-169
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• 1988

Fixed prosthetic appliance is the restorations of damaged teeth with cast metal or porcelain, and of replacing missing teeth with fixed, or cemented prosthesis. Successfully treating a patient by means of fixed prosthodontics requires the thoughtful combination of dentist and dental laboratory technician. In order to know the satisfaction of dentisits about fixed prosthetic appliances-porcelain, precious and non precious metal-, this study was conducted for 69 practicing dentisis in Pusan during Fed. to Mar. 1988 using a questionnaire method and was analyzed by the use of percentage, $X^2$-test The results are obtained as follow: 1. General characteristics of the respondents, The rate of age distribution of practcing dentists responded was as follow : 31$\sim$35 age group is 29.0%, 51$\sim$55age group 18.8%, 41$\sim$45 age group and 46$\sim$50 group each 11.6%, 36$\sim$40 age group and 56$\sim$60 age group 8.7%, over 60 age group 7.3%, below 30 age group 4.3% respectively. The tate of term of practice experience distribution of dentists responded was as follow : 6$\sim$10 year group 26.1%, 25$\sim$25year group 18.8%, 11$\sim$15 years group and 16~20 years group each 13.0%, below 5 years group and over 30 years group each 10.2%, 26$\sim$30 years group 8.7% in order. The rate of respondents’ degree was follow : bachelor group 81.2%, doctor group 13.0%, master group 5.8% in order. The rate of respondents’completed medical specialist course was as follow : non-complete group 75.4%, complete group 24.6%. The rate of having own laboratory in respondents’clinic was as follow : no having own laboratory group 58.0%, having own labiratory group 42.0% The rate of being lab. technician in respondent;s clinic was as follow: non-being lab. technician group 91.3%, being lab. technician group 8.7%. The rate of transactional commercial dental lab. numbers was as follow : I dental lab. group 40.6%, 2 dental lab. group 30.4%, 3 dental lab. group 20.3%, production at own lab. group 8.7% 2. Cognitions about the respondent's job, About cognition of patient numvers, there were neither many nor few group 62.3%, few group 17.4%, many group 15.9%, too many group 4.4% in order.(P<.01) As compared with the ratio of dentists to patient prothetic treatment, there were moderate level group 46.4%, high level group 33.6%, low level group 18.8% in order.(P<.01) By job satisfaction of respondents, the highest percentage group was satisfied group 44.9%, neither astisfied nor disstified group 33.3%, dissatisfied group 14.5%, much satisfied group 7.3%(P<.01). As compared with the level of prosthetics price, the were moderate level group 71.0%, low level group 23.2%, high level group 5.8%(P<.01) 3. Satisfaction and assessment of dissatisfied factor of the fixed prosthetic appliance, As compared with the satisfaction of al prosthetic appliance, there were neither satisfied nor dissatisfied group 59.4%, satisfied group 20.3% dissatisfied group 18.8%, much satisfied group 1.5% in order.(P<.01). About precious and non precious metal crown and bridge, there were neither satisfied nor dissatisfied group 60.9%, satisfied group 24.6%, dissatisfied group 11.6%, much satisfied group 2.9% in order.(P<.01) The reat of respondent;s satisfaction about porcelain crown and bridge was as follow : neither satisfied nor dissatisfied group 43.5%, dissatisfied group 33.3%, satisfied group 21.7%, much satisfied group 1.5%(P<.01). The rate of respondent's dissatisfied factor item of precious and non precious metal crown and bridge was as follow : inadequate margin fit item 39.1% respondent, inadequate occlusion item 24.6%, inadequate adaptation item 23.2%, poor anat omic form item 15.9%, inadequate contact item 31.9%, improper polishing item 4.4%, the rest item 11.6% respectively. The rate of respondent's dissatisfied factor item of porcelain crown and bridge was as follow : inadequate margin fit item 52.2%, inadequate occlusion item 2.9%, inadequate adaptation item 10.1%, poor anatomic form item 11.6%, improper polishing item 1.5%, shade mismatching item 71%, the rest item 7.2% respectively. The rate of cognition of respondents’ about cause of dissatisfied factor on fixed prosthetic appliance by item was as follow : deficiency of sincerity item 55.1%, deficiency of knowledge about work item 47.8%, deficiency of experience item 15.9%, poor quality of using material item 5.8%, the rest item 2.9% respectively.

• Journal of Chest Surgery
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• v.36 no.7
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• pp.497-503
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• 2003

Pulmonary aspergillosis usually results from the colonization of the existing lung lesions by chronic pulmonary diseases, such as tuberculosis. Most cases of pulmonary aspergilloma have been treated surgically for many years because it is a potentially life-threatening disease causing massive hemoptysis. Here we reviewed our results from the last 10 years. Material and Method: We reviewed 31 cases surgically treated from Aug. 1992 to Jul. 2002. retrospectively. This investigation is designed to illustrate the peak age incidence, sex ratio, chief complaints, preoperative study, anatomic location of operative site, postoperative pathologic finding and postoperative complications. Result: The peak age Incidence laid in the 3rd and 4th decade of 20 cases (64.5%). The most common complaint was hemoptysis in 27 cases (87.1%). The 31 cases had a history of treatment with anti-tuberculous drugs under impression of pulmonary tuberculosis. The 19 cases (61.3%) showed the so-called “Air-meniscus sign” on the preoperative chest X-ray. In the 31 cases (100%) on the chest computed tomography. as a preoperative diagnostic modality, positivity was shown in 37.9%, 83.3% was shown on the fungus culture of sputum for Aspergillus, serum immunodiffusion test for A. fumigatus, respectively. The anatomical location of aspergilloma was mainly in the upper lobe in 19 cases (61.3%) and the majority of cases were managed by lobectomy. The postoperative pathologic findings showed that 31 cases (100%) were combined with tuberculosis. The postoperative complications include empyema, prolonged air leakage, remained dead space, postoperative bleeding and these numbers of cases is 3 cases (9.7%), 2 cases (6.45%), 2 cases (6.45%), 1 case (3.23%), respectively. one case was died postoperatively due to massive beeding, and asphyxia. Conclusion: Compared with the previous study, there is no significant difference in results. Preoperative chest computed tomography and immunodiffusion test were more commonly available and showed high positivity. Operations often became technically difficult because of pleural space obliteration, indurated hilar structures, and poor expansion of the remaining lung, which were more prominent in the patients with complex aspergillosis. In such cases, medical treatments and interventional procedures like bronchial artery embolization are preferred. However, cavernostomy is also recommanded with few additional morbidity because of its relatively less invassiveness. Early surgical intervention is the recommended management for patients with simple aspergilloma considering the Row surgical mortality and morbidity in recent days.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.4
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• pp.409-415
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• 2011

Purpose: To design applied anamorphic lens that focal length ratio is 3:1 optical system to improve detecting distance. Methods: We defined a boundary condition as $50^{\circ}{\sim}60^{\circ}$ for viewing angle, horizontal direction 36mm, vertical direction 12 mm for focal length, f-number 4, $15{\mu}m{\times}15{\mu}m$ for pixel size and limit resolution 25% in 33l p/mm. Si, ZnS and ZnSe as a materials were used and 4.8 ${\mu}m$, 4.2 ${\mu}m$, 3.7 ${\mu}m$ as a wavelength were set. optical performance with detection distance, narcissus and athermalization in designed camera were analyzed. Results: F-number 4, y direction 12 mm and x direction 36 mm for focal length of the thermal optical system were satisfied. Total length of the system was 76 mm so that an overall volume of the system was reduced. Astigmatism and spherical aberration was within ${\pm}$0.10 which was less than 2 pixel size. Distortion was within 10% so there was no matter to use as a thermal optical camera. MTF performance for the system was over 25% from 33l p/mm to full field so it was satisfied with the boundary condition. Designed optical system was able to detect up to 2.9 km and reduce a diffused image by decreasing a narcissus value from all surfaces except the 4th surface. From sensitivity analysis, MTF resolution was increased on changing temperature with the 5th lens which was assumed as compensation. Conclusions: Designed optical system which used anamorphic lens was satisfied with boundary condition. an increasing resolution with temperature, longer detecting distance and decreasing of narcissus were verified.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.1-9
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• 1983

This study was conducted to obtain basic information on the rice anther culture. Materials used were (Inabawase X YR 2404-14-2-1) $F_1$ hybrid. Callus growth rate on various media, induction frequency of callus in spikelet and panicle, and the effect of treatment on anther and callus were evaluated. The results obtained were summarized as follows ; The growth rate of callus on N-6, M-S, P.E.agar media was 19.8, 13.1, 4.1 times respectively after 30 days inoculated, and on liquid media was 3.8, 5.1, 1.4 times, respectively. Organ differentiation on N-6, M-S, P.E.agar media was 37.5%, 12.5%, 17.5% respectively. The difference of induction frequency of callus per panicle was 0.14%-6.25% and per spikelet was 0-19.05%. Almost callus was induced 30-35 days after inoculation. Organ differentiation of induced callus was decreased by culture. Callus cultured for 13 days after induction did not make shoot. Anthers cold shocked at $8^{\circ}C$ for 5 days obtained 3.32% efficiencys of callus induction per number of anthers plated, and compared with 2.41% of no treated anthers. But anther treated at $8^{\circ}C$ for 7 days decreased 2.24%. Callus induction periods were shortened by cold treatment for about 5 days. Callus cultured on medium containing 2 mg/l of 2, 4-D showed 5% on root formation but medium containing 5 mg/l of 2, 4-D showed 30% of root formation after transfered on the medium without 2, 4-D. Callus cold shocked at $15-18^{\circ}C$ revealed poor efficiency for root formation, but 5 days treatment was good for shoot formation.

• Journal of Chest Surgery
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• v.43 no.6
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• pp.681-686
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• 2010

Background: A chest computed-tomography has become more prevalent so that it is more common to detect small sized pulmonary nodules that have not been found in previous simple chest x-ray. If those detected nodules are undersized or located in pulmonary parenchyma, it is difficult to accomplish a biopsy since it is vulnerable to explore them either grossly or digitally. Thus, in our hospital, a thoracoscopic pulmonary wedge resection was performed after locating a lesion by means of hook wire with CT-guided. Material and Method: 31 patients (17 males and 14 female patients) from December in 2006 to June in 2010 became our subjects; their 34 pulmonary nodules were subjected to the thoracoscopic pulmonary wedge resection after locating a lesion by means of hook wire with CT-guided. Also we analyzed a possibility of hook wire dislocation, a frequency of conversion to open thoracotomy, time consumed to operation after location of a lesion, operation time, post operation complication, and histological diagnosis of the lesion. Result: 12 of 34 cases were ground glass lesion, whereas 22 cases of them were solitary pulmonary lesion. The median value of the lesion was 8mm in size (range: 3 to 23 mm), while the median value was 12.5 mm in depth (range: 1 to 34 mm). The median value of time consumed from location of the lesion to anesthetic induction was 86.5 minutes (41~473 minutes); furthermore the mean value of operation time was 103 minutes (25~345 minutes). Intrathoracic wire dislocation was found in one case, but a target lesion was successfully excised. Open thoracotomy was performed in four cases due to pleural adhesion. However, there was no case of conversion to open thoracotomy due to failure to detect a target lesion. In histological diagnosis, metastatic cancer were found in 15 cases, which were the most common, primary lung cancer were in 9 cases, non-specific inflammation were in 3 cases, tuberculosis inflammation were in 2 cases, lymph nodes were in 2 cases, active tuberculosis were in 1 case, atypical adenomatous hyperplasia was in 1 case and normal lung parenchymal finding was in 1 case, respectively. Conclusion: In our hospital, in order to accomplish a precise histological diagnosis of ground-glass lesion and pulmonary nodules in lung parenchyma, location of pulmonary nodules were exactly located with hook wire under chest computed-tomography, which was followed by lung biopsy. We concluded that this was an accurate, minimally invasive and valuable method to minimize the complications and increase of cost of medical service provided.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1727-1734
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• 2005

The fermentation characteristics and mono- and di-saccharides compositions during the early stage of ensiling were studied with a temperate grass, Italian ryegrass (Lolium multiflorum Lam.) and a tropical grass, guineagrass (Panicum maximum Jacq.). The laboratory silos were kept in the room set at 25$^{\circ}C$, and then were opened on 0.5, 1, 2, 3, 5 and 7 days (14 days in Italian ryegrass) after ensiling, respectively. The Italian ryegrass silage showed a fast and large pH decrease caused by a fast and large production of lactic acid during the first 5 days of ensiling and succeeded to achieve lactic acid type fermentation; high lactic acid/acetic acid and lactic acid content at the end of ensiling (14 days), low values of pH (3.74), acetic acid, ethanol and ammonia-N/total nitrogen, none or only small amounts of Butyric acid, valeric acid and propionic acid. The guineagrass silage showed a slow decrease in pH and a slow increase in lactic acid content during the full ensiling period, causing a high final pH value, low contents of lactic acid, acetic acid, total volatile fatty acids and total organic acids. In Italian ryegrass silage, mono- and di-saccharides compositions decreased largely within the initial 0.5 day (12 h) of ensiling. Sucrose disappeared rapidly within the initial 0.5 day of ensiling, but fructose and glucose contents showed an initial rise by the activity of enzymes in plant tissues, and then decreased gradually. On the other hand, the contents of monoand di-saccharides in guineagrass showed the largest decreases due mainly to plant respiration within the initial 0.5 day of ensiling, and no initial rises in fructose and glucose contents during the early stage of ensiling because of the absence of fructans which are hydrolyzed into fructose and glucose in temperate grasses. In both silages, the rate of reduction in mono- and di-saccharides compositions within the initial 5 days of ensiling was ranked in the order of glucose>fructose>sucrose, suggesting that glucose and fructose might be more favorably utilized than sucrose by microorganisms and glucose is the first fermentation substrate. It was concluded that the silage made from Italian ryegrass with high moisture content had a good fermentation quality owing to the dominance of lactic acid bacteria and active lactic acid fermentation during the initial stage of ensiling. These results can be explained by rapid plant sap liberation and the high activity of plant enzyme hydrolyzed fructans into fructose and glucose within the initial 2 days of ensiling, which stimulate the homofermentative lactic acid bacteria growth. In ensiling a temperate grass, the physical characteristics may ensure the rapid onset of fermentation phase, which results from the smaller losses of water-soluble carbohydrates during the initial stage of ensiling and providing sufficient water-soluble carbohydrates for lactic acid bacteria. The silage made from guineagrass with intermediate dry matter and high initial mono- and di-saccharides content was stable silage. This could be explained by the higher incorporation of air during the very early stage of ensiling and the restriction of cell breakdown and juice release due to the properties of a tropical grass with coarse porosity and stemmy structures. These physical characteristics delayed the onset of lactic acid bacteria fermentation phase by extending the phases of respiration and aerobic microorganisms activity, causing the higher loss of water-soluble carbohydrates and the shortage of lactic acid bacteria fermentation substrates.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.1
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• pp.82-89
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• 2009

Two in vitro experiments were conducted to examine the effects of propionate precursors in the dicarboxylic acid pathway on ruminal fermentatation characteristics, $CH_4$ production and degradation of feed by rumen microbes. Fumarate or malate as sodium salts (Exp. 1) or acid type (Exp. 2) were added to the culture solution (150 ml, 50% strained rumen fluid and 50% artificial saliva) to achieve final concentrations of 0, 8, 16 and 24 mM, and incubated anaerobically for 0, 1, 3, 6, 9 and 12 h at $39^{\circ}C$. For both experiments, two grams of feed consisting of 70% concentrate and 30% ground alfalfa (DM basis) were prepared in a nylon bag, and were placed in a bottle containing the culture solution. Addition of fumarate or malate in both sodium salt and acid form increased (p<0.0001) pH of culture solution at 3, 6, 9 and 12 h incubations. The pH (p<0.0001) and total volatile fatty acids (VFA, p<0.05) were enhanced by these precursors as sodium salt at 3, 6 and 9 h incubations, and pH (p<0.001) and total VFA (p<0.01) from fumarate or malate in acid form were enhanced at a late stage of fermentation (9 h and 12 h) as the addition level increased. pH was higher (p<0.001) for fumarate than for malate as sodium salt at 3 h and 6 h incubations. Propionate ($C_3$) proportion was increased (p<0.0001) but those of $C_2$ (p<0.05) and $C_4$ (p<0.01 - p<0.001) were reduced by the addition of sodium salt precursors from 3 h to 12 incubation times while both precursors in acid form enhanced (p<0.011 - p<0.0001) proportion of $C_3$ from 6h but reduced (p<0.018 - p<0.0005) $C_4$ proportion at incubation times of 1, 3, 9 and 12 h. Proportion of $C_3$ was increased (p<0.05 - p<0.0001) at all incubation times by both precursors as sodium salt while that of $C_3$ was increased (p<0.001) from 6h but $C_4$ proportion was decreased by both precursors in acid form as the addition level increased. Proportion of $C_3$ was higher (p<0.01 - p<0.001) for fumarate than malate as sodium salt from 6 h incubation but was higher for malate than fumarate in acid form at 9 h (p<0.05) and 12 h (p<0.01) incubation times. Increased levels (16 and 24 mM) of fumarate or malate as sodium salt (p<0.017) and both precursors in acid form (p<0.028) increased the total gas production, but no differences were found between precursors in both chemical types. Propionate precursors in both chemical types clearly reduced (p<0.0001 - p<0.0002) $CH_4$ production, and the reduction (p<0.001 - p<0.0001) was dose dependent as the addition level of precursors increased. The $CH_4$ generated was smaller (p<0.01 - p<0.0001) for fumarate than for malate in both chemical types. Addition of fumarate or malate as sodium type reduced (p<0.004) dry matter degradation while both precursors in both chemical types slightly increased neutral detergent fiber degradability of feed in the nylon bag.