• KSBB Journal
• /
• 제13권4호
• /
• pp.411-417
• /
• 1998

The possibility of application of membrane type immobilized adsorbent to the fed-batch or perfusion culture system with anchorage-independent cells as well as batch system was investigated. The improvement in cell density and cell viability due to the combination of immobilized adsorbent with each culture system was evaluated for the investigation, and the optimum culture system employing immobilized adsorbent system was suggested based on the results. It was observed that the system with immobilized adsorbent showed better cell growth and cell viability than that without immobilized adsorbent in every operation system of batch, fed-batch, and perfusion. In case of batch system, 200% improvement of maximum cell density was observed in the system where ammonium chloride was added on purpose. And 50% improvement of maximum cell density was observed in the fed-batch system where ammonium ion accumulates significantly, while small increase in maximum cell density was observed in the perfusion system where dilution of waste byproducts exists. Especially, the fed-batch system showed the most significant improvement on cell growth because both compensation of nutrient and removal of ammonium ion occurred simultaneously in the system. Therefore a combined system of immobilized adsorbent and fed-batch operation could be suggested as an optimum system with in situ removal of ammonium ion.

• Advances in pediatric surgery
• /
• 제4권2호
• /
• pp.100-109
• /
• 1998

The anomalous pancreaticobiliary duct union (APBDU) might cause the formation of choledochal cyst and malignancies of hepatopancreaticobiliary system. The purpose of this study is to make an experimental animal model of APBDU similar to that of human. One to two-month-old Mongrel dogs (n=12) were divided into two groups; the control group (n=2) had a sham operation performed, and in the experimental group (n=10) the end of distal ' common bile duct (CBD) was anastomosed to the side of the dorsal pancreatic duct making APBDD. Serum was obtained for chemical analysis on the 10th postoperative day. The dogs were sacrificed at the 5th week (n=3), the 6th week (n=3), the 7th week (n=2), the 8th week (n=2) and the 6th month (n=2) after the experimental surgery. With sacrifice, operative cholangiogram was taken, and bile juice was obtained for chemistry and bacterial culture. The en-bloc specimens of the hepatopancreaticobiliary system were removed for microscopic examination. Serum and bile juice amylase levels were elevated in the experimental group(n=10), but not in the control group(n=2). Operative cholangiograms of control group revealed no evidence of bile duct dilatation.. On the other hand, the bile duct in the experimental group was markedly dilated without any evidence of stenosis at the anastomosis site (n=10). Histologic examination of the hepatopancreaticobiliary system in the experimental group resembled the findings of choledochal cyst in human. The APBDU of this animal model can produce bile duct dilatation by pancreaticobiliary reflux. We think that this animal model can be potentially promising for the research about the APBDU associated hepatopancreaticobiliary diseases.

• Asian-Australasian Journal of Animal Sciences
• /
• 제6권1호
• /
• pp.139-145
• /
• 1993

Biogas created from animal waste is a precious energy source. A practical and successful utilization of the biogas is not easy, because there lie some difficulties in biogas production and facilities investment. In this study, the requisites for a successful biogas utilization were discussed. The production results obtained in the previous operation of anaerobic digestion plant were used for the simulation. When the slurry heating was designed for constant biogas generation, depreciation costs of the facilities amounted 1,175,000 yen per year, and biogas productions at $24.5^{\circ}C$, $30.0^{\circ}C$ and $35.5^{\circ}C$ were $16.8m^3$, $17.6m^3$ and $25.1m^3$, respectively. Removal ratios of organic matters were not so high. At $35.5^{\circ}C$, energy value of the biogas produced was estimated 125.5 Mcal per day, and the following heat loss (y Mcal/day) was brought about by the temperature difference ($X^{\circ}C$) between the digester and atmosphere; y = 0.769X - 5.375. The costs of biogas production per cow were assumed to decrease according to enlargement of feeding scale, especially on scales of more than 30 cows. On recent levels of costs and prices of energy in Japan, they were nearly equal to 2 to 3 fold of the price of municipal mixed gas when a anaerobic digester was compulsorily heated and kept at $30.0^{\circ}C$ or $35.5^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
• /
• 제28권7호
• /
• pp.1053-1060
• /
• 2015

In this study, the optimal operation factors for struvite crystallization for removing and recovering nitrogen and phosphorus from anaerobic digestive fluid of swine manure containing highly concentrated nitrogen was determined. Every experiment for the struvite crystallization reaction was conducted by placing 1,000 mL of digestion fluid in a 2,000 mL Erlenmeyer flask at various temperatures, pH, and mixing speed. Except for special circumstances, the digestion fluid was centrifuged (10,000 rpm, 10 min) and then the supernatant was used for the experiment at room temperature and 100 rpm. The optimal mole ratio of $PO_4{^{3-}}:Mg^{2+}$ was 1:1.5, and the pH effect ranging from 9 to 11 was similar, when mixed for 1 hour. Under this condition, the removal efficiency of $NH_4{^+}-N$ and $PO_4{^{3-}}-P$ was 40% and 88.6%, respectively. X-shaped crystal was observed by light and scanning electron microscopy. In addition, struvite crystal structure was confirmed through X-ray diffraction analysis.

• Asian-Australasian Journal of Animal Sciences
• /
• 제13권3호
• /
• pp.307-312
• /
• 2000

Fasting heat production (FHP) of growing buffalo calves (Bubalus bubalis) in the body weight range of 76 to 236 kg was determined using open circuit respiration chamber. The details of the chambers, calibration of gas analysers and operation of the systems are described. Animals were fasted for 96 hrs during which only water was provided. FHP was determined during next 24 hrs. The mean oxygen consumed, carbon dioxide and methane produced and urinary N excretion per 24 h was $17.03{\ell}$, $11.70{\ell}$, and $0.12{\ell}$ and 0.35 g respectively. The mean respiratory quotient ranged from 0.68 to 0.71, which indicated that post absorptive stage is reached after 96 hrs in growing buffalo calves previously fed ammoniated straw-based ration. Mean FHP of calves was $331.4kJ/kg\;W^{0.75}$. FHP of calves with range of mean body weights of 167 to 235 kg, although nonsignificant but, was almost 12% higher than of calves having mean body weight of 101 kg. Suitable exponent to body weight to describe FHP of buffalo calves was 0.87.

• 한국동물위생학회지
• /
• 제35권1호
• /
• pp.77-82
• /
• 2012

Inflammatory pseudotumor (IPT) is a term defining a mass characterized microscopically by a proliferation of bland mesenchymal spindle cells infiltrated by diffuse mixed inflammatory cells with a predominance of plasma cells and lymphocytes. Here, we show the primo vessel-like structure of the primo-vascular system (PVS) in a dog with IPT. A 6-years old male Mongrel dog was diagnosed with an abnormal mass (diameter 5.5 cm, weight 22 g) near left preputial area. The dog was submitted to the surgical detectomy of the mass. During the surgical operation, we observed primo vessel-like material. After fixations, the masses appeared macroscopically as lipoid-like, firm, white to grey masses, measuring $5{\times}8cm$. Histologically, cellular infiltration into the muscular layers was frequently seen. The mesenchymal proliferation remained the main component of the mass and was composed of myofibroblastic-like spindle cells characterized by globular, irregular nuclei containing open chromatin and a prominent nucleolus. On the basis of the histopathologic lesions, the subcutaneous mass was diagnosed as IPT. Also, we detected a primo vessel-like structures in some areas of the IPT tissues. These were observed as novel thread-like structures and bundle of tubular structures. To our knowledge, this report is the first case of primo vessel-like structure in a dog with IPT.

• Journal of Chest Surgery
• /
• 제20권3호
• /
• pp.458-472
• /
• 1987

A heart supplies bloods of about 15, 000 liters to each human organ in a day. A normal function of heart valves is necessary to this act of heart. The disease of heart valve develops to a narrowness of a closure, resulting in an abnormal circulation of bloods. In an attempt to eliminate the affliction of heart valves, the operation method to repair with artificial heart valves has been developed and saved numerous patients over past 30 years. This replacement operation has been performed since early 1960`s in Korea, but all the artificial heart valves used are imported from abroad with very high costs until recent years. The artificial heart valve using pyrolytic carbon has been developed at KAIST, which was proved to be stable in the mechanical performance and durability. Therefore, the in viva performance of this valve was examined through animal tests. The artificial heart valves used in this study are tilting disc type valves, in which the disc were made of graphite coated with pyrolytic carbon and the cages were made of titanium. In viva testings of these valves were performed in 12 dogs, in which right ventriculo-pulmonary arterial [Croup I] or inter-aortic [Croup IV] valved conduit was implanted using polytetrafluoroethylene conduits containing KAIST valve and aortic valve [Group II] or pulmonary valve [Croup III] was replaced by a KAIST valve with a 21mm or 19mm tissue annulus diameter. In group I and II, pre-and post-operative transvalvular pressure gradient was measured and compared with other prosthetic valves. During post operative period laboratory examination was performed including hemoglobin, hematocrit, red cell count, white cell, lactic acid dehydrogenase and platelet. The eight surviving dogs were sacrificed and autopsy was performed at 2, 6, and 8 weeks. KAIST valve has low transvalvular gradient and relatively high orifice area. Average ventriculo-aortic peak systolic transvalvular gradient was 14 mmHg in 21 mm valve and 19 mmHg in 19 mm valve. The valve has slight intravascular hemolysis effect. Thrombogenic effect of low polishing quality and eddy currents around small orifice is high. The valve has vulnerability of disc movement. These animal tests suggest that the improvement of the heart valve design, surface polishing state and prescription methods.

• 한국농공학회논문집
• /
• 제60권2호
• /
• pp.75-84
• /
• 2018

Thermal stress of livestock has been issued due to recent climate change trends and this causes reproductive disorders, decreased feed consumption, immunosuppression, and increased mortality of animals. Concept of THI has been widely used to quantitatively evaluate the degree of thermal stress for animals, however use of this concept is restricted for animals living in the enclosed facilities such as mechanically ventilated broiler houses. In this study, time-based internal energy flow and variation trends of temperature and humidity were analyzed based on BES technique. Local weather data, insulation characteristics of building materials, heat and moisture generation rate from broilers according to age, algorithm of ventilation operation were adopted for boundary condition of the model to accurately compute THI values inside the mechanically ventilated broiler house. From the BES computation, excess frequency of THI threshold in Jeju city was highest on the assumption that air conditioning equipments were not installed. When general raising density ($39kg\;m^{-2}$) was adopted, total 2,191 hours were exceeded. Excess hours of THI threshold were strongly related to the cumulative air temperature ($R^2=0.87$).

• Asian-Australasian Journal of Animal Sciences
• /
• 제33권9호
• /
• pp.1520-1532
• /
• 2020

Objective: Due to rapid economic return, mixed crop-swine farming systems in Korea have become more intensive. Intensive farming practices often cause nutrient surpluses and lead to environmental pollution. Nutrient budgets can be used to evaluate the environmental impact and as a regulatory policy instrument for nutrient management. This study was conducted to select a nutrient budgeting approach applicable to the mixed crop-swine farms in Korea and suggest an effective manure treatment method to reduce on-farm nutrient production. Methods: In this study, we compared current and ideal gross nutrient balance (GNB) approaches of Organisation for Economic Co-operation and Development and soil system budget (SSB) approach with reference to on-farm manure treatment processes. Data obtained from farm census and published literature were used to develop the farm nutrient budgets. Results: The average nitrogen (N) and phosphorus (P) surpluses were approximately 11 times and over 7 times respectively higher in the GNB approaches than the SSB. After solid-liquid separation of manure, during liquid composting a change in aeration method from intermittent to continuous reduced the N and P loading about 50% and 47%, respectively. Although changing in solid composting method from turning only to turning+aeration improved the N removal efficiency by 30.5%, not much improvement in P removal efficiency was observed. Conclusion: Although the GNB approaches depict the impact of nutrients produced in the mixed crop-swine farms on the overall agricultural environment, the SSB approach shows the partitioning among different nutrient loss pathways and storage of nutrients within the soil system; thus, can help design sustainable nutrient management plans for the mixed cropswine farms. The study also suggests that continuous aeration for liquid composting and turning+aeration for solid composting can reduce nutrient loading to the soil.

• 한국축산시설환경학회지
• /
• 제6권2호
• /
• pp.105-112
• /
• 2000

본 연구는 로봇착유기 개발을 위한 기초연구로서 유두위치 측정장치와 로봇제어 시스템을 구성하고 그 성능을 분석하고자 수행되었으며 그 결과는 다음과 같다. 1. 유두인식은 스테레오 측량법에 기초한 이미지 장치로 처리했으며 유두인식오차는 (x, y, z) = (0.83, 1.95, 0.81)mm이다. RCS로 좌표값을 변환했을 때 시스템 전체의 오차는 x = 0.9mm, y = 2.0mm, z = 0.9mm였다. 2. 로봇 유두컵 착탈 시스템의 로봇 착탈 성공률은 평균 91.5%로 나타났다. 작업시간은 27.8sec였으며, 이미지 처리를 포함한 전체 작업시간은 86.1sec로 나타났다.