• Journal of Korean Society of Environmental Engineers
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• v.33 no.7
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• pp.516-522
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• 2011

The largest problem of domestic anaerobic digestion is low digestion efficiency. Reasons of the problem would be low organic matters input, low mixing efficiency in digestion tank, refractory excess sludge etc.. In this study, screw attached disk-type concentration system and a mechanical mixing system, solubilization facility improvements were performed to solve problems. Through these improvements, the sludge conc. of the concentrator increased 2.6-fold and the volume reduction efficiency was increased 3.0-fold. In addition, the dead-space is reduced by mechanical agitation. Anaerobic digester gas production in the digestion tank is increased from $193.8m^3$ to $386.0m^3$ per day. Digestion efficiency is improved to 54.6% from 47.6%. Digestion gas production is increased from $0.30Nm^3/kg$ VS to $0.42Nm^3/kg$ VS.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.701-705
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• 2007

Seven rc mutant and seven normal male birds (Rhode Island Red suie, RIR) were used in this study to determine the effects of rc mutation on semen characteristics, testosterone profile and spermatogenic tissues. All birds were randomly selected at week 12 of age and housed in individual cages and were fed and watered ad libitum. The birds were exposed to a 14L:10D light cycle during experiment. Semen were collected at weeks 22 to 23 from each bird twice a week and evaluated for semen volume (SV), sperm concentration (SC), total sperm count (TSC), percent of sperm motility (%SM), dead sperm (%DS), and sperm metabolic activity (SMA). To determine the testosterone concentration (TC) in plasma, blood was collected at weeks 12, 16 and 18. Testicular tissue were collected, processed and evaluated for semineferous tubule diameter (STD), round spermatid number (RSN), percent elongated sperm (%ES) and semineferous tubules length (STL). Body weight (BW), comb weight (CW) and testes weight (TW) were weighted at the end of experiment (week 23). The SV, TSC and %SM were significantly higher in normal birds but the %DS was higher in blind birds (p<0.05). The SC did not differ significantly between the two groups but its value was higher in normal birds. The sperm metabolic activity in the first h of collection did not differ significantly between the two groups but after 24 h, the level of SMA in normal group was significantly higher (p<0.05). The level of TC did not differ significantly between the two genotype groups but normal birds had higher TC in all collections except the last one. The STD, RSN, %ES and STL in normal birds were higher when compared to blind birds but the differences were insignificant except for ES percent. The BW, CW and TW between the two groups did not differ significantly but the weights were higher in normal group compared to blind birds. Statistical analysis of semen characteristics, testosterone profile and histological factors were indicated detrimental effects of rc mutation in prepubertal RIR blind male birds due to lack of light.

• The korean journal of orthodontics
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• v.44 no.1
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• pp.20-27
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• 2014

Objective: The aims of this study were to evaluate the relationship between the detachment force and bonding resin surface are and to determine the resin bonding surface area that would provide adequate bonding strength with minimum resin volume. Methods: One hundred and sixty human premolars were randomly divided into 4 groups of 40 teeth each. The diameter of the resin surface area in each group was as follows: group 1, 1.5 mm; group 2, 2.5 mm; group 3, 3.5 mm; and group 4, 4.5 mm. Respond Dead Soft straight (length 0.0175 inch) was used to fabricate the retainers, and $Transbond^{TM}$ XT was used to fix the retainers to the tooth surfaces. A pair of teeth was embedded in acrylic blocks for each specimen. Thus, each group comprised 20 samples. Fixed retainers were bonded to the teeth, and vertical force was applied at the middle of wire. The force was measured using a universal testing machine. Results: The mean value of detachment force was the highest for group 4 ($102.38{\pm}2.92N$), followed by group 3 ($63.54{\pm}2.21N$), group 2 ($51.95{\pm}1.61N$), and group 1 ($24.14{\pm}1.38N$). Conclusions: The detachment force of lingual fixed retainers was significantly affected as the area of the resin bonding surface increased. Considering the minimum bonding strength of brackets, a resin bonding surface area with a diameter of 3.5 mm would provide adequate bonding strength.

• Carbon letters
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• v.8 no.4
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• pp.274-279
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• 2007

In order to understand the breakthrough behaviour of iodine vapours on impregnated carbon systems, an active carbon, 80 CTC grade, $12{\times}30$ BSS particle size and $1104\;m^2/g$ surface area, was impregnated with metal salts such Cu, Cr, Ag, Mo and Zn, and an organic compound Triethylene diamine (TEDA) to prepare different carbon systems such as whetlerite, whetlerite/TEDA, whetlerite/KI/KOH and ASZMT. The prepared adsorbents along with active carbon were characterized for surface area and pore volume by $N_2$ adsorption at liquid nitrogen temperature. These carbon systems were compared for their CT (concentration X time) values at 12.73 to 53.05 cm/sec space velocities and 2 to 5 cm carbon column bed heights. The carbon column of 5.0 cm bed height and 1.0 cm diameter was found to be providing protection against iodine vapours up to 5.5 h at 3.712 mg/L iodine vapour concentration and 12.73 cm/sec space velocity. The study clearly indicated the adsorption capacities of carbon systems to be directly proportional to their surface area values. Dead layer with all the prepared carbon systems was found to be less than 2.0 cm indicating it to be minimum bed height to have protection against $I_2$ vapours. Effect of carbon bed height and flow rate was also studied. The active carbon showed maximum protection at all bed heights and flow rates in comparison to all other impregnated carbon systems, showing that only physical adsorption is responsible for the removal of iodine vapours.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.3
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• pp.318-323
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• 1997

In order to assess the effect of solar exposure on pulmonary functions and evaporative losses from skin and pulmonary surfaces, in six healthy Sahiwal (S) and six Sahiwal ${\times}$ Holstein ($S{\times}H$) cattle were exposed to direct sun during summer. Breed differences were observed during exposure. Increase in sweating rate was higher in crossbreds (222%) than in Sahiwal (125%). Pre-exposure (ambient temperature, $32.6{\pm}0.85^\circ}C$, solar radiation, $0.9cal\;cm^{-2}min^{-1}$) evaporative loss from skin accounted for about 90% of the losses and remaining losses were contributed by pulmonary surfaces in Sahiwal. The contribution of evaporation through skin increased to 92% (ambient temperature $39.4{\pm}0.68^\circ}C$, solar radiation, $1.35cal\;cm^{-2}min^{-1}$). In crossbreds 80% of the evaporative losses were through skin before exposure which increased to 87% after exposure to solar radiations. Rectal temperature increase was higher in crossbreds ($1.5^{\circ}C$) than in Sahiwal ($0.8^{\circ}C$). With the increase in pulmonary evaporative losses, respiratory frequency increased to 2 fold in Sahiwal and pulmonary ventilation increased 1.6 times the resting value in Sahiwal due to solar exposure. In $S{\times}H$ crossbreds the respiratory frequency increased 3.5 times and pulmonary ventilation increased only to 1.8 times due to decrease in tidal volume. There was about 2 fold increase in alveolar ventilation in both the breeds, the increase in dead space ventilation was more in crossbreds than in Sahiwal. Behavioral symptoms exhibited by animals after exposure were profuse salivation, open mouth panting, tongue protrusion and general restlessness.

• Ocean and Polar Research
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• v.31 no.4
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• pp.349-357
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• 2009

Ballast water is widely recognized as a serious environmental problem due to the risk of introducing non-indigenous aquatic species. In this study we aimed to investigate measures which can minimize the transfer of aquatic organisms from ballast water. Securing more reliable technologies to determine the viability of aquatic organisms is an important initiative in ballast water management systems. To evaluate the viability of marine phytoplankton, we designed the staining methods of fluorescein diacetate (FDA) and Calcein-AM assay on each target species belonging to different groups, such as bacillariphyceae, dinophyceae, raphidophyceae, chrysophyceae, haptophyceae and chlorophyceae. The FDA method, which is based on measurements of cell esterase activity using a fluorimetric stain, was the best dye for determining live cells of almost all phytoplankton species, except several diatoms tested in this study. On the other hand, although fluorescence of Calcein-AM was very clear for a comparatively longer time, green fluorescence per cell volume was lacking in most of the tested species. According to the Flow CAM method, which is a continuous imaging technique designed to characterize particles, green fluorescence values of stained cells by FDA were significantly higher than those of Calcein-AM treatments and control, implying that the Flow CAM using FDA assay could be adapted as an important tool for distinguishing living cells from dead cells. Our results suggest that the FDA and Calcein-AM methods can be adapted for use on phytoplankton, though species-specific characters are greatly different from one organism to another.

• Biomolecules & Therapeutics
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• v.8 no.2
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• pp.160-166
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• 2000

The present study examined influence of various ischemic duration on extent of focal ischemic brain injury induced by middle cerebral artery occlusion (MCAO) in rats. The MCAO was produced by insertion of a 17 mm silicone-coated 4-0 nylon surgical thread to the origin of MCA through the internal carotid artery for 30, 60, 90, 120 min (transient) or 24 hr (permanent) in male Sprague-Dawley rats under isoflurane anesthesia. Reperfusion in transient MCAO models was achieved by pulling the thread out of the internal carotid artery. Only rats showing neurological deficits characterized by left hemiparesis and/or circling to the left, were included in cerebral ischemic groups. The rats were sacrificed 24 hr after MCAO and seven serial coronal slices of the brain were stained with 2,3,5-triphenyltetrazolium chloride. Infarct size was measured using a computerized image analyzer. Ischemic damage was common in the frontoparietal cortex (somatosensory area) and the lateral segment of the striatum while damage to the medial segment of the striatum depended on the duration of the occlusion. In the 30-min MCAO grouts, however, infarcted region was primarily confined to the striatum and it was difficult to clearly delineate the region since there was mixed population of live and dead cells in the nucleus. Infarct volume was generally increased depending on the duration of MCAO, showing the most severe damage in the permanent MCAO group. However, there was no significant difference in infarct size between the 90-min and 120-min MCAO groups. % Edema also tended to increase depending on the duration of MCAO. The results suggest that the various focal ischemic rat models established in the present study can be used to evaluate in vivo neuroprotective activities of candidate compounds or to elucidate pathophysiological mechanisms of ischemic neuronal cell death.

• Archives of Plastic Surgery
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• v.36 no.6
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• pp.714-719
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• 2009

Purpose: Recurrent ischial pressure sore is troublesome for adequate soft tissue coverage, because usually its pocket has a very large deep space and adjacent donor tissue have been scarred in the previous surgery. However, the conventional reconstructive methods are very difficult to overcome them. Modified gluteus maximus myocutaneous V - Y advancement flap from buttock can be successfully used in these circumstances. Methods: From February 2007 to October 2008, modified gluteus maximus myocutaneous V - Y advancement flaps were perfomed in 10 paraplegic patients with recurrent ischial pressure sore. The myocutaneous flap based on the inferior gluteal artery was designed in V - shaped pattern toward the superolateral aspect of buttock and was elevated from adjacent tissue. Furthermore, when additional muscular bulk was required to obliterate dead space, the flap dissection was extended to the inferolateral aspect which can included the adequate amount of the gluteal muscle. After the advanced flap was located in sore pocket, donor defect was repaired primarily. Results: The patients' mean age was 46.9 and the average follow - up period was 12.4 months. The immediate postoperative course was uneventful. But, two patients were treated through readvancement of previous flap due to wound dehiscence or recurrence after 6 months. The long - term results were satisfied in proper soft tissue bulk and low recurrence rate. Conclusions: The modified gluteus maximus myocutaneous V - Y advancement flap may be a reliable method in reconstruction of recurrent ischial pressure sore, which were surrounded by scarred tissue because of its repetitive surgeries and were required to provide sufficient volume of soft tissue to fill the large pocket.

• Journal of Sensor Science and Technology
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• v.8 no.4
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• pp.320-326
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• 1999

A small cartridge, with a nozzle system for washing off the dirt from the surfaces of sensing gates, was fabricated. The proposed nozzle structure was designed for cartridge by using the simulation tool of fluid (CFD-ACE). Whole size of the fabricated cartridge by using micromachining techniques is about $2.6\;cm{\times}1.5\;cm$, the size of the washing nozzle is $0.2\;mm{\times}0.6\;mm$ and its dead volume is only about $20\;{\mu}l$. A micro-reference electrode was achieved by employing a differential system with ISFETs/QRE (quasi-reference electrode)/REFET (reference field-effect transistor). Metal electrodes was deposited at both ends of blowing channel were used to check the presence of bubble in the microchannel. The pH-ISFET was inserted into the fabricated cartridge and the washing effect of the nozzle system in cartridge was invested.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.65-65
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• 2011

Early-type galaxies represent the end point of galaxy evolution and, despite pervasive residual star formation, are generally considered "red and dead", that is composed exclusively of old stars with no star formation. Here, their molecular gas content is constrained and discussed in relation to their evolution, supporting the continuing importance of minor mergers and/or cold gas accretion. First, as part of the Atlas3D survey, the first complete, large, volume-limited survey of CO in normal early-type galaxies is presented. At least of 23% of local early-types possess a substantial amount of molecular gas, the necessary ingredient for star formation, independent of mass and environment but dependent on the specific stellar angular momentum. Second, using CO synthesis imaging, the extent of the molecular gas is constrained and a variety of morphologies is revealed. The kinematics of the molecular gas and stars are often misaligned, implying an external gas origin in over a third of all systems, more than half in the field, while external gas accretion must be shot down in clusters. Third, many objects appear to be in the process of forming regular kpc-size decoupled disks, and a star formation sequence can be sketched by piecing together multi-wavelength information on the molecular gas, current star formation, and young stars. Fourth, early-type galaxies do not seem to systematically obey all our usual prejudices regarding star formation (e.g. Schmidt-Kennicutt law, far infrared-radio continuum correlation), suggesting a greater diversity in star formation processes than observed in disk galaxies and the possibility of "morphological quenching". Lastly, a first step toward constraining the physical properties of the molecular gas is taken, by modeling the line ratios of density- and opacity-sensitive molecules in a few objects. Taken together, these observations argue for the continuing importance of (minor) mergers and cold gas accretion in local early-types, and they provide a much greater understanding of the gas cycle in the galaxies harbouring most of the stellar mass. In the future, better dust masses and dust-to-gas mass ratios from Herschel should allow to place entirely independent constraints on the gas supply, while spatially-resolved high-density molecular gas tracers observed with ALMA will probe the interstellar medium and star formation laws locally in a regime entirely different from that normally probed in spiral galaxies.