• Journal of Chest Surgery
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• v.31 no.7
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• pp.643-649
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• 1998

Background: For the patient with chronic obstructive pulmonary disease requiring long-term oxygen therapy, oxygen concentrator machines are already widely available for use in home. In this study, we used mongrel dogs as test subjects to compare the functional efficiency and safety of the oxygen concentrator developed by our own research team with those of the imported FORLIFE(TM) machine made by AIRSEP Corp. Method and method: To test mechanical reliability, the concentrations of oxygen delivered were measured after 4 hours of continuous operation. Sixteen mongrel dogs were divided into two equal groups. Mongrel dogs in group A were given oxygen using the imported oxygen concentrator, and those in group B using the machine developed. 5 l/min of oxygen were given, after which vital signs were analyzed, arterial blood gases measured, and blood chemistry tests carried out. Results: After 4 hours of continuous operation, the imported model performed better, giving 98${\pm}$3% oxygen, compared to our model, which gave 91${\pm}$1%. In the animal experiments, oxygen concentrations were measured at the inlet of face mask 1, 2, 3, and 4 hours after continuous administration, and there was no statistically significant difference(repeated measures of analysis of variance p=0.70) between the values of 70.6${\pm}$2.5%, 67.1${\pm}$2.9%, 68.2${\pm}$2.6%, and 64.9${\pm}$3.9% that were measured from group A, and the values of 65.1${\pm}$4.8%, 65.2${\pm}$3.6%, 68.7${\pm}$4.3%, and 66.0${\pm}$5.0% measured from group B. Before oxygen administration, and at 1, 2, 3, and 4 hours after oxygen administration, arterial blood partial pressure of oxygen 87.2${\pm}$2.5 mmHg, 347.4${\pm}$29.3 mmHg, 353.4${\pm}$21.2 mmHg, 343.0${\pm}$28.8 mmHg, and 321.6${\pm}$24.4 mmHg, respectively, were read from group A, which were not statistically different (p=0.24) to the values of 102.5${\pm}$9.6 mmHg, 300.3${\pm}$17.1 mmHg, 321.6${\pm}$23.7 mmHg, 303.4${\pm}$27.4 mmHg, and 273.5${\pm}$25.9 mmHg read from group B. Nonetheless, the arterial blood partial pressure of oxygen values appear to be somewhat higher in dogs that were given oxygen using the imported oxygen concentrator. Conclusions: From these results the prototype oxygen concentrator developed appears to function relatively satisfactorily compared to the imported, established model, but may be criticized for the excessive noise generated and poor long-term endurance or consistency, which need improvement.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.12
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• pp.696-704
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• 2015

This study was carried out to evaluate the optimum operational condition of Semi-continuously Fed and Mixed Reactor (SCFMR) to treat the dairy cow manure and saw dust mixture. Step-wise increase in organic loading rates (OLRs) or decrease in hydraulic retention times (HRTs) were utilized until the biogas volume became significantly decreased at mesophilic temperature ($35^{\circ}C$). The optimum operating condition of the SCFMR fed with TS 13% dairy cow manure and saw dust mixture was found to be an HRTs of 25 days and its corresponding OLRs of $4.45kg\;VS/m^3-day$. At this condition the biogas and methane production rates were 1.44 v/v-d and 1.12 v/v-d (volume of biogas per volume of reactor per day), respectively and the TVS removal efficiency of 37% was achieved. The successful operation with such a high OLR was due to the high reactor alkalinity concentration of 14,500~15,600 mg/L as $CaCO_3$ as a result of the characteristic of the original substrate, dairy cow manure and saw dust mixture whose alkalinity was more than 8,000 mg/L as $CaCO_3$. The parameters for the reactor stability, the ratios of volatile acids and alkalinity concentrations (V/A) and the ratio of propionic acid and acetic acid concentrations (P/A) appeared to be 0.11 and 0.43, respectively, that were greatly stable in operation. Free ammonia toxicity was not experienced due to the long term acclimation by the reactor TS content ranged 7.2~10.4% during the entire operational period.

• Journal of Animal Environmental Science
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• v.18 no.1
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• pp.1-8
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• 2012

The study was conducted to investigate the effects of climate on indoor environment of a swine house with natural. This study was tested in the beef swine stall at Young-in, Kyung-ki do. The test was experimented for the effect of interior environment by the outdoor environment and the interior-pan. The results are as follows. 1. In test 1 ($T_{out}$ : $25.7^{\circ}C$, without fan), an indoor air flow pattern was showed that entered from sidewall winch-curtain to went out of a indoor by the ridge winch-curtain. And the velocity of a section of the center was measured two times as large as the velocity of the floor. It is the acceleration of the velocity by thermal buoyancy. And, the entered air was rapidly dissipated by flow energy. So that in the swain livestock with sidewall winch-curtain is effected by thermal buoyancy. And the air temperature of the indoor was distributed more higher as compared with the outdoor temperature. This result is caused by the sensible heat from swine and the ventilation is restricted. 2. In test 2 (($T_{out}$ : $25.7^{\circ}C$, with fan), the velocity of a section of the center was measured more higher as compared with the test 1. And the variance of air velocity was distributed higher as compared with the test 1. This result is showed dead region of air flow with a fan operation. And, the variance of gas density was distributed lower as compared with the test 1.

• The Korean Journal of Physiology
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• v.1 no.2
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• pp.169-175
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• 1967

An experiment was designed to see if the hippocampus exerts any influence upon the aggressive behavior of male rats. Fighting between rats was observed for the estimation of aggressiveness. Seventeen rats in which the hippocampus was almost totally removed through a small hole with a diameter around 3 mm made in the neocortex at the boundary between the parietal and occipital lobes (hippocampal group), 8 rats with similar neocortical damage alone (operated control group), and 17 normal control rats (normal group) were prepared and subjected to the experiment 3 months after the operation. Applying electric shock of short duration to the feet in a box with grid floor, a fight was provoked between an animal belonging to the hippocampal group and one belonging to the nor-mal group, between a rat of the hippocampal group and one of the operated control group, and also between a rat of the operated control group and one of the normal group. Three observers judged the performance of each animal independently and described it as winning, defeated, tied, or non-fighting. Fifteen shocked trials were administered to each pair of animals with around 2 minutes' interval between each trial. An animal received a 'judging score' of 3 when it won more frequently than was defeated, a judging score of 2 when it won as frequently as was defeated, when all fights were tied, or when no fighting occurred, while it received a judging score of 1 when it won less frequently than was defeated. Group differences in performances were analyzed in terms of judging score using Kolmogorov-Smirnov test for one sample. The results obtained were as follows: 1. In the fights between the hippocampal and the normal groups, the hippocampal animals made significantly better judging scores than the normal animals did (Table 1). 2. There was no significant difference between the hippocampal and the operated control group as to the judging scores they made in the course of fights between the two groups. However, the hippocampal animals tended to dominate over the operated control group as judged by comparing the total 'winning' of the former (30) to that of the latter (14) (Table 2). 3. The total judging score made by the operated control group in the course of the fights against the normal group was not significantly superior to that made by the normal group (Table 3). It was inferred from the above results that, though inconspicuous, the hippocampus tended to exert an inhibitory influence upon the aggressive behavior of male rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.993-1005
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• 1996

This study was implemented in order to investigate the effects of dietary calcium-salt, estrogentreatment, and estrogen/calcium treatment on bone metabolism. Ovariectomized rats were used as animal models. Female Sprague-Dawley rats with a body weight of 250~280g were underwent ovariectomy or sham-operation. The ovariectomized rats were divided into 9 different experimental groups including the saline-treated group, the estrogen-treated group, the high calcium salt-treated group, and the estrogen/calcium treated groups and fed for 6 weeks. Creatinine and hydroxyproline in urine were analyzed. Creatinine, calcitonin, osteocalcin, alkaline phosphatase and parathyroid hormone in plasma were also determined. The results of the experiment are as follows : The ovariectomy caused a significant increase in the level of food intake, food effciency ratio and body weight gain in comparison with sham-operation. The overall food intake, food effciency ratio and body weight gain were significantly decreased by estrogen. The ovariectomized animals developed obesity as a result of increased food intake. In addition, estradiol injections suppressed food intake with a concomitant loss in body weight. The level or urinary hydroxyproline, as an indicator or bone resorntion, was higher in the ovariectomized rats compared to sham-opertion, while these decresed in the estrogen/calcium treated group. Parathyroid hormone and calcitonin in the plasma, that were used as the indicator of calcium homeostasis, parathyroid hormone higher in the ovariectomized rats compared to sham-operation. It was lowered by estrogen and high calcium treated groups; thus, estrogen and estrogen/calcium treated groups were decreased by 32% compared to saline treated group. Osteocalcin and alkaline phosphatase which are indicators of bone formation, were significantly higher in ovariectomized group, while this showed to be decreased in the estrogen and the ostrogenicalcium treated groups. Estrogen and estrogen/calcium in ovariectomized rats resulted in lower bone loss. However, estrogen treated group its gradual reduction showed little effect on bone loss, while the gradual reduction of estrogen had a preventive effect on bone loss when the treatment was combined with calcium intensification.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.283-294
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• 2004

Air quality in the livestock waste compost pilot plant at the Colligate Livestock Station was assessed to quantity the emissions of aerial contaminants and evaluate the degree of correlation between them for different operation strategies; with the ventilation types and agitation of compost pile, in this study. The parameters analyzed to reflect the level of air quality in the livestock waste compost pilot plant were the gaseous contaminants; ammonia, hydrogen sulfide, and odor concentration, the particulate contaminants; inhalable dust and respirable dust, and the biological contaminants; total airborne bacteria and fungi. The mean concentrations of ammonia, hydrogen sulfide, and odor concentration in the compost pilot plant without agitation were 2.45ppm, 19.96ppb, and 15.8 when it was naturally ventilated, and 7.61ppm, 31.36ppb, and 30.2 when mechanically ventilated. Those with agitation were 5.50ppm, 14.69ppb, and 46.4 when naturally ventilated, and 30.12ppm, 39.91ppb, and 205.5 when mechanically ventilated. The mean concentrations of inhalable and respirable dust in the compost pilot plant without agitation were 368.6${\mu}g$/$m^3$ and 96.0${\mu}g$/$m^3$ with natural ventilation, and 283.9${\mu}g$/$m^3$ and 119.5${\mu}g$/$m^3$ with mechanical ventilation. They were also observed with agitation to 208.7${\mu}g$/$m^3$ and 139.8${\mu}g$/$m^3$ with natural ventilation, and 209.2${\mu}g$/$m^3$ and 131.7${\mu}g$/$m^3$ with mechanical ventilation. Averaged concentrations of total airborne bacteria and fungi in the compost pilot plant without agitation were observed to 28,673cfu/$m^3$ and 22,507cfu/$m^3$ with natural ventilation, and 7,462cfu/$m^3$ and 3,228cfu/$m^3$ with mechanical ventilation. They were also observed with agitation to 19,592cfu/$m^3$ and 26,376cfu/$m^3$ with the natural ventilation, and 18,645cfu/$m^3$ and 24,581cfu/$m^3$ with the mechanical ventilation. It showed that the emission rates of gaseous pollutants, such as ammonia, hydrogen sulfide, and odor concentration, in the compost pilot plant operated with the mechanical ventilation and with the agitation of compost pile were higher than those with the natural ventilation and without the agitation. While the concentrations of inhalable dust and total airborne bacteria in the compost pilot plant with the natural ventilation and with the agitation, the concentrations of respirable dust and total airborne fungi in the compost pilot plant with the mechanical ventilation and agitation were higher than those with the natural ventilation and without the agitation of compost pile. It was statistically proved that indoor temperature and relative humidity affected the release of particulates and biological pollutants, and ammonia and hydrogen sulfide were believed primary malodorous compounds emitted from the compost pilot plant.

• BMB Reports
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• v.32 no.4
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• pp.331-338
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• 1999

Ethanol catabolism is thought to produce metabolic disorders resulting in alcoholic liver disease. To investigate the mutual effects of ethanol catabolism and cholestasis induced by common bile duct ligation on the activities of carboxylesterase, we have determined the enzyme activities in rat hepatic (cytosolic, mitochondrial, and microsomal) preparations as well as in rat serum using ten animal models: normal rats (group 1), sham-operated rats (group 2), common bile duct-ligated rats (group 3), ethanol-intoxicated rats (group 4), sham-operation plus chronic ethanol-intoxicated rats (group 5), common bile duct-ligated plus chronic ethanol-intoxicated rats at 1.5h and 24h (groups 7A and 7B), and duct-ligated and acute ethanol intoxicated rats at 1.5 h and 24 h (groups 8A and 8B). The $K_m$ and $V_{max}$ values of carboxylesterase from these hepatic preparations of cholestatic rat liver combined with chronic ethanol intoxication were also measured by using ethyl valerate as the substrate from the 14th day post-ligation. Carboxylesterase activities of all hepatic preparations and rat serum (group 3) showed significant decreases compared to the activities from the sham-operated control (group 2). Enzyme kinetic parameters indicated that $V_{max}$ of carboxylesterase from all the hepatic preparations in cholestatic rats (group 3) decreased significantly, although the $K_m$ values were about the same as in the sham-operated control (group 2). When cholestasis was combined with chronic ethanol intoxication (group 6), carboxylesterase activities showed further decrease in all the hepatic preparations and serum compared to the control activity (group 5). The $V_{max}$ also decreased significantly, although $K_m$ values did not change. When common bile duct ligation was combined with acute ethanol intoxication (group 8), the enzyme activities in the rat liver and serum showed significant decrease compared to the activity from acute ethanol-intoxicated rats (group 7). However, quite contrary to this, the activities of serum from acute ethanol intoxication 1.5 h (group 7A) increased significantly compared to the activities in the normal control (group 1). These results, therefore, suggest that the biosynthesis of hepatic carboxyl-esterase seems to decrease when cholestasis is combined with chronic and acute ethanol intoxication, and the decrease in activity is more significant than from cholestasis alone.

• Journal of Veterinary Clinics
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• v.25 no.3
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• pp.170-175
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• 2008

The present study was performed to investigate the anesthetic or analgesic effect of tiletamine-zolazepam (TZ) and electro acupuncture analgesia (EAA) in cats. Twelve healthy cats were randomly assigned to receive either TZ or EA. TZ group cats with weight of $3.65{\pm}0.48kg$ received 10.0 mg/kg of TZ intramuscularly. EA group cats with weight of $3.62{\pm}0.52kg$ received 5V, 30Hz and 60 minutes of EA. The acupoints used were Tian-ping (GV-5, +), Bai-hui (GV-20, -). Therefore, after and before experiment, some serum chemistry profiles (alkaline phospatase, aspartate aminotransferase, alanine aminotransferase, glucose and total protein) and change of vital signs (rectal temperature, heart rate, respiratory rate) were examined. All cats were examined pre, and 5, 25, 65 and 105 minutes after administration of TZ or operation of EA. The cats in EA group showed a smaller change in rectal temperature, heart rate and respiratory rate than in the TZ group (p<0.05). In both groups, total protein concentration was constant throughout the period of anesthesia, and the serum glucose increased gradually throughout the period of anesthesia. However, the cats in EA group showed a smaller change in alkaline phospatase, aspartate aminotransferase and alanine aminotransferase within the limit of safety than in the TZ group (p<0.05). While coming to induction, the TZ group took a mean $2.4{\pm}0.7$ minutes to achieve sternal recumbency, compared with $10.5{\pm}2.1$ minutes by the EA group, and $3.2{\pm}0.6$ minutes to achieve lateral recumbency, compared with $18.8{\pm}1.9$ minutes by the EA group (p<0.05). When recovering from anesthesia, the TZ group took $164.3{\pm}17.9$ minutes to achieve sternal position time, compared with $67.7{\pm}4.6$ minutes by the EA group, and $202.0{\pm}15.7$ minutes to stand, compared with $73.0{\pm}6.1$ minutes for the EA group (p<0.05). In this study, the cats anesthetized with EA showed a more rapid recovery rather than the cats under TZ anesthesia. Also, there do not appear to be any negative physiologic effects associated with acupuncture-induced surgical analgesia. So, it was considered that EAA may be used effectively in shock, debilitated cats, as compared to TZ.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.467-475
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• 2001

Cardiac arrest, hypoxia, shock or seizure has been known to induce cerebral ischemia. This study was designed to investigate the effect of ischemia on hippocampal pyramidal layer induced by transient bilateral occlusion of the common carotid arteries. Mature Mongolian gerbils were sacrificed at days 2, 4, and 7 after carotid occlusion for 10 minutes. Sham-operated gerbils of control group were subjected to the same protocol except for carotid occlusion. During operation for ischemia, body temperature was maintained $37{\pm}0.5^{\circ}C$ in all gerbils. Paraffin-embedded brain tissue blocks were cut into coronal slices and stained with H-E stain or immunostain by TUNEL method. Neurons with the oval and prominent nucleus and without the eosinophilic cytoplasm in the subfield of hippocamapal pyramidal layer were calculated as to be viable neurons. Their chromatins were condensed or clumped. Their nuclei appeared multiangular or irregularly shrinked. The width of the pyramidal layer was reduced due to the loss of nuclei. At day 2 after reperfusion, some neurons in the CA1 subfield were slightly eosinophilic. But most neurons in the CA2 subfield were strongly eosinophilic. At day 4 day, most neurons in the CA1 subfield were severely damaged and at day 7 day, only a few survived neurons were observed. Survived neurons per longitudinal 1mm sector in the CA1, CA2, CA3, and CA4 subfields of pyramidal layer were investigated. At day 2, the mean numbers of pyramidal neurons in CA1, CA2, CA3, and CA4 subfiedls were 104.5/mm (54.3%), 51.0/mm (33.8%), 105.5/mm (85.6%), and 124.3/mm (93.5%) compared to the nonischemic control group, respectively. At day 4, the mean numbers of pyramidal neurons in CA1, CA2, CA3, and CA4 subfields were 3.2/mm (1.7%), 51.5/mm(34.2%), 95.3/mm (77.4%), and 112.5/mm (84.6%), respectively. At day 7, the mean numbers of pyramidal neurons in CA1, CA2, CA3, and CA4 subfiedls were 0.8/mm (0.4%), 5.7/mm(3.8%), 9.8/mm (8.0%), and 5.0/mm (3.7%), respectively. The mean numbers of apoptotic positive neurons in the CA1 subfield at day 2, 4, and 7 after reperfusion were 67.8/mm, 153.2/mm and 123.7/mm, respectively. These results suggest that the transient cerebral ischemia cause severe damages in most neurons at day 7 and that the prosminent apoptotic positive neurons in hippocampal pyramidal layer are the delayed neuronal death induced by ischemia.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.339-344
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• 2010

Oxygen depleted water mass can damage aquatic animals not only in direct way but also in indirect way by generating toxic substances including occurrence of hydrogen sulfide and ammonia which are also highly detrimental to animal life in the water mass. An oxygen dissolution device was developed, which makes turnover of the oxygen rich (over 20 mg/L) surface water down to the bottom where hypoxia is evident and tested the device in terms of oxygen recovery in the oxygen depleted bottom water. the device with turnover rates of $3.6\;m^2$/min at the liquid oxygen injection rate of 48~26.3 L/min could recover dissolved oxygen level to 7~25 mg/L at depth 7 m to lead to the dissolution level of over 90% by the supply of liquid oxygen. The running advantage of the device is that it does not require any auxiliary tank and higher energy for operation. Therefore, it can be highly useful device to relieve damages to the farmed animals in the oxygen depleted waters.