• Microbiology and Biotechnology Letters
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• v.2 no.1
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• pp.29-35
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• 1974

We have studied the applicability of the principles and inherent advantages of the two-stage dontinuous uclture technique to an enzyme process for the purpose of improving and optimizing the productivity of 3-ketosteroid-delta-1-dehydrogenase. By using a two-stage continuous culture system, the growth st ageand enzyme produdtion stage are separated. In each stage an optimal set of toperaing conditions was determined, and this was tested for feasibility for the period of 10 days. During this period, at least 70％ of the maximum enzyme productivity could be maintained. The important design parameters studied are: (1) optimal specific growth rate in the first stage which corresponds to the maximal cell productivity, (2) the optimal dilution rate in the second stage which in turn determines the size of second stage fermentor and the mean residence time of cells in the second stage, (3) cell concentration in both stages, add (4) the specific enzyme productivity and enzyme productivity of the second stage. In addition, by using two-stage continuous culture system we have been able to reduce or eliminate the effect of catabolite repression due to high medium concentration and the adverse effect of the solvent used to dissolve the inducer. We have found the balance between the opposing effects of induction and repression in the second stage judging from the observation that the enzyme productivity goes through a maximum.

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.85-88
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• 2000

Distributed Control System(DCS) is one of the best solutions to implement control systems because it provides continuous observation of control process and execution of commands to induce proper operations. In this paper, a design of control network for DCS in nuclear power plant is proposed. The proposed control network on DCS has a simple architecture and deterministic property. Thus, the proposed control network offers hard real-time periodic service. It also has redundant media for the fault-tolerance. As a result, high safety and reliability required in nuclear power plant are guaranteed.

• Mycobiology
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• v.51 no.3
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• pp.164-168
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• 2023

This study examined the effects of myristate on an asymbiotic culture of Rhizoglomus intraradices, a species of arbuscular mycorrhizal fungi (AMF; Glomeromycota). Mycelial growth and sporulation in a modified medium containing myristate were observed. The findings demonstrated that myristate induced R. intraradices spore formation, with daughter spores having a smaller diameter than the parent spores. This observation is consistent with previous studies on other Rhizoglomus species. Further studies are needed to investigate the potential for continuous culture, mass production using daughter spores, and the application of AMF colonization techniques in plants.

• Journal of Biomedical Engineering Research
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• v.16 no.4
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• pp.415-424
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• 1995

Combined models, specified by two or more modeling formalisms, can represent a wide variety of complex systems. This paper describes a methodology for the development of combined models in two model types of discrete event and continuous process. The methodology is based on transformation of continuous state space into discrete one to homomorphically represent dynamics of continuous processes in discrete events. This paper proposes a formal structure which can combine model of the DES and the CS within a framework. The structure employs the DEVS formalism for the DES models and differential or polynomial equations for the CS models. To employ the proposed structure to specify a DEVS/CS combined model, a modeler needs to take the following steps. First, a modeler should identify events in the CS and transform the states of the CS into the DES. Second, a modular employs the formalism to specify the system as the DES. Finally, a moduler developes sub-models for the CS and continguos states of the DES and establishs one-to-one correspondence between the sub-models and such states. The proposed formal structre has been applied to develop a DEVS/CS combined model for the human cardiovascular system. For this, the cardiac cycle is partitioned into a set of phases based on events identified through observation. For each phase, a CS model has been developed and associated with the phase. To validate the DEVS/CS combined model developed, then simulate the model in the DEVSIM + + environment, which is a model simulation results with the results obtained from the CS model simulation using SPICE. The comparison shows that the DEVS/CS combined model adequately represents dynamics of the human heart system at each phase of cardiac cycle.

• Journal of Pharmacopuncture
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• v.14 no.3
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• pp.19-45
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• 2011

Objectives: This study was performed to analyse the effects of Sweet Bee Venom(Sweet BV-pure melittin, the major component of honey bee venom) on the central nervous system in rats. Methods: All experiments were conducted at Biotoxtech Company, a non-clinical studies authorized institution, under the regulations of Good Laboratory Practice (GLP). Male rats of 5 weeks old were chosen for this study and after confirming condition of rats was stable, Sweet BV was administered in thigh muscle of rats. And checked the effects of Sweet BV on the central nervous system using the functional observational battery (FOB), which is a neuro-toxicity screening assay composed of 30 descriptive, scalar, binary, and continuous endpoints. And home cage observations, home cage removal and handling, open field activity, sensorimotor reflex test/physiological measurements were conducted. Results: 1. In the home cage observation, there was not observed any abnormal signs in rats. 2. In the observation of open field activity, the reduction of number of unit areas crossed and rearing count was observed caused by Sweet BV treatment. 3. In the observation of handling reactivity, there was not observed any abnormal signs in rats. 4. In the observation of sensorimotor reflex tests/physiological measurements, there was not observed any neurotoxic signs in rats. 5. In the measurement of rectal temperature, treatment of Sweet BV did not showed great influences in the body temperature of rats. Conclusions: Above findings suggest that Sweet BV is relatively safe treatment in the central nervous system. But in the using of over dose, Sweet BV may the cause of local pain and disturbance of movement. Further studies on the subject should be conducted to yield more concrete evidences.

• Journal of Gastric Cancer
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• v.24 no.2
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• pp.199-209
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• 2024

Purpose: Long-term outcomes of patients with positive lateral margins (pLMs) after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). This study aimed to evaluate the remnant cancer and survival rates of patients with pLMs compared with those who underwent curative resection. Materials and Methods: A retrospective analysis was performed on consecutive patients with pLMs as the only non-curative factor of expanded indication who underwent ESD for EGC with a follow-up duration of 5 years or more. The rates of remnant cancer, recurrence, and survival were analyzed and compared to those of control patients who underwent curative resection by propensity score matching. Results: Among 3,515 patients treated with ESD between 2005 and 2018, 123 non-curative EGCs were retrospectively analyzed. A total of 108 patients were followed up without endoscopic or surgical resection for 8.2 years. The control group was matched in a 1:1 ratio with patients with EGC who underwent curative resection after ESD. The observation group with pLMs had a higher incidence of remnant cancer (25.9%; 28/108) compared to that in the curative resection group (0/108; P=0.000). The remaining tumors were treated with surgical or endoscopic resection, and no additional recurrences were observed. The overall survival analysis demonstrated no significant difference between the observation and curative resection groups (P=0.577). Conclusions: No difference was observed in the overall survival rate between observation and curative resection groups. Therefore, observation may be a possible option for incomplete ESD with pLMs if continuous follow-up is performed.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.1
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• pp.9-20
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• 1997

The precise leveling is one of the important means of investigating fluctuation of earth's crust and foreknowing earthquake. This paper aims to study refraction errors developed in the inclined leveling route. Based on Kukkamaki's theory and data of weather, the author devised an experiment to test how Kukkimaki's corrections improved the discrepancy between fore and back sight leveling in actual slope. Additionally, through the repeated observation between fore and back sight leveling at one fixed station in the slope(2/100-4/100) and the experimental tests of continuous inclined leveling route, the author studied the effects and charcteristics of refraction. Especially, in inclined leveling(2/100-4/100), the distance of line of sight is ideally to be 25-30 m to minimize refraction errors. From the results of experimental tests of continuous inclined leveling route, the values of calculation by Kukkimaki's corrections were found to be nearly in accord with the values of observation.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1365-1371
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• 2011

The intensity and duration of sexual behavior in Bos indicus was assessed through the continuous observation of sexual receptivity. Two groups of cows were formed: only synchronized (n = 50) and other group further superovulated (n = 20). An intravaginal implant that released progesterone over 9 d was used. After removing the implant, 25 mg of $PGF_{2{\alpha}}$ was administered. In the superovulated group, the administration of 280 mg (Follicle stimulant hormone) FSH-P1 per cow with a decreasing dosage over 4 d was utilized. In both groups, behavioral observations began at the moment of implant removal. Sexual behavior was analyzed using a Kruskal-Wallis test to compare the mean of hours in estrus, effective mountings and number of mounts/hour during estrus. A nonparametric survival analysis was performed using the time in two ways: i) when an event happened it was placed in a 24 h timeframe and, ii) the time of observation in continuous form (96 h) assessing the difference between curves by the log rank test Chi-square. The only significant difference was the number of mounts/h during receptivity (p<0.05). In the superovulated group three periods of sexual activity during the day were identified, with these events being of greater frequency and duration than the synchronized group (p = 0.02); besides, the superovulated group began estrus before the synchronized group (p = 0.0035) when using the total period. In a simulation study, when the number of observations went from two (06:00-18:00) to three periods (06:00, 12:00 and 18:00) cows detected accurately (<6 h after the onset) increased more than 20%. The results show that superovulated cows presented greater intensity and duration of sexual activity in contrast with only synchronized animals.

• Journal of Korea Foundry Society
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• v.23 no.5
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• pp.276-285
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• 2003

In the undercooled melt of $Pd_{40}Cu_{30}Ni_{10}P_{20}$ alloy, the solidification behavior including nucleation and growth of crystals at the micrometer level has been observed in-situ by use of a confocal scanning laser microscope combined with an infrared image furnace. The $Pd_{40}Cu_{30}Ni_{10}P_{20}$ alloy specimens were cooled from the liquid state to glass transition temperature. 575 K, at various cooling late under a helium gas flow. According to the cooling rate, the morphologies of the solidification front are changed among various types, irregular jog like front, columnar dendritic front, cellular grain, star like shape jog and fine grain, etc. The velocities of the solid-liquid interface are measured to be $10^{-5}{\sim}10^{-8}$ m/s which are at least two orders higher than the theoretical crystal growth rates. Combining the morphologies observed in terms of cooling rates and their solidification behaviors, we conclude that phase separation takes place in the undercooled molten $Pd_{40}Cu_{30}Ni_{10}P_{20}$ alloy. The continuous cooling transformation (CCT) diagram was constructed from solidification onset time at various linear cooling conditions with different rate. The CCT diagram suggests that the critical cooling rate for glassy solidification is about 1.5 K/s, which is in agreement with the previous calorimetric findings.

• Journal of the Society of Disaster Information
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• v.18 no.4
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• pp.746-753
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• 2022

Purpose: The purpose of this study is to review the safety of small tunnels for food storage excavation in the 1960s~1970s and to improve the stability of small tunnels. Method: A visual inspection and a hammer test were used to conduct safety tests, and the visual inspection is one of the tests conducted for non-destructive testing, and the hammer test is one of the types of hitting methods of rebound hardness. Result: According to the integrated analysis of the survey area data, there are generally good appearance, but there are many small cracks and complex geological conditions, requiring continuous observation and attention. Seven of the 23 tunnels require safety diagnosis, one collapse, one safe, and 14 require continuous observation and attention. Conclusion: All parts of small tunnels should be checked and recorded from time to time, and stability is expected to be improved when reinforcing small tunnels proposed in this study.