• Journal of Pharmaceutical Investigation
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• v.30 no.3
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• pp.191-199
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• 2000

Genomics is providing targets faster than we can validate them and combinatorial chemistry is providing new chemical entities faster than we can screen them. Historically, the drug discovery cascade has been established as a sequential process initiated with a potency screening against a selected biological target. In this sequential process, pharmacokinetics was often regarded as a low-throughput activity. Typically, limited pharmacokinetics studies would be conducted prior to acceptance of a compound for safety evaluation and, as a result, compounds often failed to reach a clinical testing due to unfavorable pharmacokinetic characteristics. A new paradigm in drug discovery has emerged in which the entire sample collection is rapidly screened using robotized high-throughput assays at the outset of the program. Higher-throughput pharmacokinetics (HTPK) is being achieved through introduction of new techniques, including automation for sample preparation and new experimental approaches. A number of in vitro and in vivo methods are being developed for the HTPK. In vitro studies, in which many cell lines are used to screen absorption and metabolism, are generally faster than in vivo screening, and, in this sense, in vitro screening is often considered as a real HTPK. Despite the elegance of the in vitro models, however, in vivo screenings are always essential for the final confirmation. Among these in vivo methods, cassette dosing technique, is believed the methods that is applicable in the screening of pharmacokinetics of many compounds at a time. The widespread use of liquid chromatography (LC) interfaced to mass spectrometry (MS) or tandem mass spectrometry (MS/MS) allowed the feasibility of the cassette dosing technique. Another approach to increase the throughput of in vivo screening of pharmacokinetics is to reduce the number of sample analysis. Two common approaches are used for this purpose. First, samples from identical study designs but that contain different drug candidate can be pooled to produce single set of samples, thus, reducing sample to be analyzed. Second, for a single test compound, serial plasma samples can be pooled to produce a single composite sample for analysis. In this review, we validated the issue whether the second method can be applied to practical screening of in vivo pharmacokinetics using data from seven of our previous bioequivalence studies. For a given drug, equally spaced serial plasma samples were pooled to achieve a 'Pooled Concentration' for the drug. An area under the plasma drug concentration-time curve (AUC) was then calculated theoretically using the pooled concentration and the predicted AUC value was statistically compared with the traditionally calculated AUC value. The comparison revealed that the sample pooling method generated reasonably accurate AUC values when compared with those obtained by the traditional approach. It is especially noteworthy that the accuracy was obtained by the analysis of only one sample instead of analyses of a number of samples that necessitates a significant man-power and time. Thus, we propose the sample pooling method as an alternative to in vivo pharmacokinetic approach in the selection potential lead(s) from combinatorial libraries.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.216-224
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• 1983

This work was undertaken to obtain some characteristics of proteolytic enzyme of marine gastropods such as sea hare, Aplysia kurodai, top shell, Turbo cornutus, and abalone, Haliotis discus hannai. An influence of pH, temperature and some chemicals on proteolytic activity of the crude enzyme extracted from digestive tract of the samples was taken into account and the stability of the enzyme during the storage at low temperature was also discussed. In comparison of the activities of the crude enzyme from the samples to the optimum conditions, it was characterized that abalone has twice or the more times higher activities than the other two species of the gastropoda in the acid and weak acid region, while, in the alkaline region, sea hare has six or the more times higher acitivities than the other two species. The proteolytic activity was facilitated by $Mn^{2+}$, some reducing agents, EDTA and DTT, and inhibited by $Hg^{2+}$ and SDS, but the other chemicals were not significantly affected to the activity. The low temperature storage of the enzymes of sea hare and top shell at $0^{\circ}C\;or\;-20^{\circ}C$ was not affected to the enzymic activity under the optimum pH condition except in the alkaline region. On the other hand, the low temperature storage was brought about no significant effect on the activity of the enzymes extracted from abalone under the optimum condition of the weak acid region, but apparently influenced to the activity under the optimum condition of the acid and alkaline region.

• Journal of Environmental Science International
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• v.26 no.8
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• pp.967-976
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• 2017

In this study, the effect of probiotic supplementation on growth performance, blood metabolites, and meat quality of Hanwoo steer was investigated. A total of 32 Hanwoo steers (15-17 months, average body weight $462{\pm}37.9kg$) were randomly allotted to 4 dietary treatments (0, 0.5, 1.0, and 1.5% mixed probiotics), with four Hanwoo steers per pen (two replicates per treatments), and reared for 12 months. There were no differences among treatments in growth performance of Hanwoo steer (P>0.05); however, feed intake decreased linearly with increasing levels of mixed probiotics. Growth hormone and Blood Urea Nitrogen (BUN) levels responded linearly with increasing levels of dietary mixed probiotics (P<0.05), but not insulin and blood glucose did not. In particular, total cholesterol was significantly lower for the 1% mixed probiotic treatment in comparison with that of the other treatments (P<0.05). The pH, Thiobarbituric Acid Reactive Substances (TBARS), cooking loss, and meat color were influenced by increasing levels of mixed probiotics (P<0.05), but the carcass characteristics and shear force were not. Regarding sensory evaluation, the addition of mixed probiotics resulted in significant difference in meat color, tenderness, aroma, off-flavor, juiciness, and marbling score, but not in overall acceptability. In addition, fatty acid profiles indicated no differences between control and mixed probiotic treatments. In conclusion, mixed probiotic treatment at 1% levels can enhance consumer preferences possibly by reducing cholesterol and TBARS.

• Journal of the Korean Electrochemical Society
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• v.3 no.3
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• pp.162-168
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• 2000

The influence of phenolsulfunate concentrations on electroplating characteristics and electrochemical behaviors was investigated with a viewpoint of electrolyte aging using the circulation cell and potentiostate And comparison of tinplate coating appearance such as glossiness and Image clarify has been also studied with varying of phenolsulfonic acid (PSA) solutions. As the aging of electrolyte proceeded, the limiting current density was moved to a lower current density region by the limitation of mass transfer, and higher phenolsulfunate concentrations resulted in the narrower optimum current density range and deterioration of coating surface of tinplates. The difference of the limiting current density was not remarkable with increasing electrolyte temperature. Thus the electrolyte aging was attributed to the limitation of thermally-activated process such as mass transfer of reducible ions. It has also been considered that the accumulation of phenolsulfonate suppressed normal electrotinning reaction by reducing the mobility of stannous ions, taking into account of the smaller effect of electrolyte aging. Experiments showed similar polarization behavior between the electrolyte of high phenolsufonate solution and the aged one, which comes to conclude that the accumulation of phenolsulfonate is one of the major causes of electrolyte aging.

• Journal of Korea Water Resources Association
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• v.39 no.8 s.169
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• pp.669-676
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• 2006

Hydrological factors, especially the spatial distribution of interpretation on precipitation is often topic of interest in studying of water resource. The popular methods such as Thiessen method, inverse distance method, and isohyetal method are limited in calculating the spatial continuity and geographical characteristics. This study was intended to overcome those limitations with improved method that will yield higher accuracy. The monthly and yearly precipitation data were produced and compared with the observed daily precipitation to find correlation between them. They were then used as secondary variables in Co-kriging method, and the result was compared with the outcome of existing methods like inverse distance method and kriging method. The comparison of the data showed that the daily precipitation had high correlation with corresponding year's average monthly amounts of precipitation and the observed average monthly amounts of precipitation. Then the result from the application of these data for a Co-kriging method confirmed increased accuracy in the modeling of spatial distribution of precipitation, thus indirectly reducing inconsistency of the spatial distribution of hydrological factors other than precipitation.

• The Korean Journal of Mycology
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• v.10 no.4
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• pp.181-185
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• 1982

Immature apple fruits of cultivars Fuji and Miller were completely resistant to Macrophoma sp. until 10 July. When inoculated on 31 July, apples became susceptible to this fungus, irrespective of cultivar. This fungus grew better on Fuji than Miller. Lesion enlargement on apple at $25^{\circ}C$ was remarkably pronounced relative to $20^{\circ}C$. In both cultivars, the amount of total soluble carbohydrates or reducing sugars in apple fruit flesh was gradually increased as apples became mature. The healthy apples of cultivar Fuji had a higher amount of carbohydrates than those of Miller. The infected apples contained more soluble carbohydrates in comparison to the healthy ones. In healthy apples, there were no consistent differences between Fuji and Miller in amount of total soluble amino acids. With increasing age of apples, the amount of soluble amino acids declined in the fruit flesh of both cultivars. Levels of carbohydrates and amino acids in apple fruits were discussed in association with the immature fruit resistance to Macrophoma sp.

• Tribology and Lubricants
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• v.34 no.3
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• pp.84-92
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• 2018

Bearings are essential for reducing vibration and wear, in order to achieve high durability and increase longevity. White metal treatment of tilting pads via centrifugal casting method has the possibility of increasing durability. However, this manufacturing method has drawbacks such as long processing time, high defect rate, and harmful health effects. Laser cladding deposition technique is a powerful method that can address these issues by decreasing the processing time and providing good adhesion. In this study, we suggest optimum conditions for laser cladding deposition that can be used in industrial applications. We deposited a soft white metal layer on SCM440 that is primarily used in shafts to minimize wear of bearing pads. During the laser deposition process, we controlled factors such as laser power, powder feed rate, and laser head speed to determine the optimum conditions. In addition, we measured the hardness using micro Vickers, and performed field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and friction tests to investigate the mechanical properties and surface characteristics for different parameters. Based on the experimental results, we suggest that laser power, powder feed rate, and laser head speed of 1.3 kW, 2.5 rpm, and 10 mm/s, respectively, constitute the optimum conditions for producing white metals using laser cladding.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.1
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• pp.167-175
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• 2018

This research deals, The characteristics of mechanics and behavior of the tube structural systems, It has been investigated and considered conventional theory and case models, It has shown the suitability, The best location, And optimal shape of the unit module system, Considered variables materials of stiffness increase and decrease in hybrid tube structural systems this study carried out adapting analysis of statistical concepts. In a concrete way, This study exams the effect of reducing horizontal displacement and the shear lag phenomenon, Also, The purpose of this study is to utilize the basic data on the design and study of future high-rise hybrid structural system using this research. As a result, The framed- tube structural system does not effectively cope with horizontal behavior of high-rise buildings, The results of using varying material tested resistance factors and lateral loads in hybrid tube structural system, When each material is compared Bracing material is identified as a key factor in lateral behavior. In a ratio of material quantity framed-tube structural system, The level of sensitivity affecting the horizontal displacement is greater then the beam's column, In case of braced tube structural system, Braced appeared to be most sensitive in comparison of material quantity ratio in columns and beams.

• Korean Journal of Plant Resources
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• v.37 no.1
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• pp.62-70
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• 2024

Fruit thinning rate and characteristics were investigated for three years on seven promising pear (Pyrus pyrifolia Nakai) cultivars, which were treated by lime-sulfur as an eco-chemical thinning substance. Lime-sulfur was treated twice at the second and third days after full bloom by cultivar. Most of pear cultivars were significantly thinned by lime-sulfur compounds. Especially 'Whangkeumbae', 'Supergold' and 'Hanareum' exhibited high flower thinning rates, 41.5%, 40.1% and 39.9%, respectively. As weather conditions at the lime-sulfur treatment, insolation and cloud amount were correlated with flower thinning rate but not significant (r = 0.49 and r = -0.45, respectively). These results suggest that lime-sulfur is suitable for reducing labor force for flower thinning of Korean pears but flower thinning effects of lime-sulfur can vary depending on other factors such as environmental conditions. This information will provide useful data for low labor force cultivation of Korean pear cultivars.

• Journal of the Korean earth science society
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• v.30 no.2
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• pp.223-233
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• 2009

Three-dimensional (3-D) optimally-interpolated sea surface temperature (SST) field was produced by using AQUA/AMSR-E satellite data, and its limitations were described by comparing the temporal average of sea surface temperatures. The 3-D OI (Optimum Interpolation) SST showed a small error of less than $0.05^{\circ}C$ in the central North Pacific, but yielded large errors of greater than $0.4^{\circ}C$ at the coastal area where the satellite microwave data were not available. OI SST composite around pixels with no observation due to heavy rainfall or cloudy pixels had estimation errors of $0.1-0.15^{\circ}C$. Comparison with temporal means showed a tendency that overall OI SSTs were underestimated around heavy cloudy pixels and smoothed out by reducing the magnitude of SST fronts. In the low-latitude areas near the equator, OI SST field produced discontinuity, originated from the window size for the OI procedure. This was mainly caused by differences in the spatial scale of oceanic features. Infernal Rossby deformation radius, as a measure of spatial stale, showed dominant latitudinal variations with O(1) difference in the North Pacific. This study suggests that OI SST methodology should consider latitudinally-varying size of window and the characteristics of spatial scales of oceanic phenomena with substantial dependency on latitude and vertical structure of density.