• Title/Summary/Keyword: Controlling Effects

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Controlling Sacbrood Virus Disease in Apis cerana Colonies with Biological Methods in Korea

  • Vung, Nguyen Ngoc;Kim, Iksoo;Lee, Man Young;Kim, Hye Kyung;Kim, Dong Won;Choi, Yong Soo
    • Journal of Apiculture
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    • v.33 no.4
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    • pp.283-295
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    • 2018
  • As Sacbrood virus (SBV), a causative agent of larval death and colony collapse in Apis cerana honey bee, is prevalent and poses one of the most significant threats to the Korean apiculture, development of methods to counter this viral disease is urgently needed. In this study we tested some SBV controlling methods, such as requeen, shook swam, adding Apis mellifera and spraying yogurt to SBV inoculated colony. Colony size measured by number of sealed brood and adult were evaluated every 15 days until two months while instances of recurrence were recorded up to five months after applying treatment methods. We also test the effects of yogurt on healthy and SBV-infected larvae at both in vitro reared larvae and colony level. Our result showed that all SBV controlling methods had similar success rates with respect to elimination of SBV clinical symptom up to 30 days post treatment. Mix-species and spraying yogurt method had similar pattern of sealed brood and adult number and higher than that of other SBV controlling methods up to 45 days post treatment. These two groups also showed the lower percentage of SBV recurrence (50% and 66.7%) at 120 days post treatment than other group that mostly colony had clinical symptom. Result on in vitro reared larvae challenged with yogurt showed that yogurt have neither harmless on healthy larvae nor remedial effect on SBV infected larvae. However, at colony level, colony in group received yogurt treatment removed significantly more SBV-infected larvae, SBV-killed larvae, and even healthy larvae in comparison to the control, suggested that yogurt could trigger the hygienic behavior of nurse bee. Our results recommended that it is practical in beekeeping by adding A. mellifera and spraying yogurt to control SBV in A. cerana colony.

Effect of the Non-Elastic Taping Method of Controlling Internal Hip Joint Rotation on Hip Muscle Activity: A Preliminary Study (엉덩관절 안쪽돌림 조절을 위한 비탄력 테이핑 방법이 엉덩관절 근활성도에 미치는 영향 -예비연구-)

  • Song-Ui Bae;Ju-Hyeon Jung;Dong-Chul Moon
    • PNF and Movement
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    • v.21 no.3
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    • pp.281-289
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    • 2023
  • Purpose: This study investigated the effects of the non-elastic taping method for controlling internal hip joint rotation on internal and external hip rotator muscle activity in healthy people. Methods: In this study, 18 healthy volunteers were instructed to perform the small knee bending (SKB) test. All participants completed the test following two methods (using non-elastic taping and not using taping). Muscle activation during the two methods was measured using a surface electromyography (EMG) device. Surface EMG data were collected from the gluteus medius, gluteus maximus, and tensor fasciae femoris muscles while performing the SKB test with and without non-elastic taping. Results: Muscle activity in the gluteus maximus was significantly higher during the SKB test with non-elastic taping than during the conventional SKB test with taping (p < 0.05). Tensor fasciae latae muscle activity was lower during the SKB test with non-elastic taping than during the conventional SKB test (p < 0.05). Conclusion: The findings suggest that the non-elastic taping method for controlling internal hip joint rotation effectively activates the hip's external rotator muscles and minimizes unwanted internal rotator muscle use during the SKB test. Therefore, the non-elastic taping method for controlling internal hip joint rotation could be an effective intervention for those who cannot control the internal rotation of their hips.

Antifungal Activities of Crude Extractum from Camellia semiserrata Chi (Nanshancha) Seed Cake Against Colletotrichum musae, Colletotrichum gloeosporioides and Penicillium italicum in vitro and in vivo Fruit Test

  • Meng, Xiangchun;Li, Jun;Bi, Fangcheng;Zhu, Lixue;Ma, Zhiyu
    • The Plant Pathology Journal
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    • v.31 no.4
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    • pp.414-420
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    • 2015
  • Antifungal activities of crude extractum of Nanshancha Seed Cake (NSC), to inactivate postharvest pathogens were investigated. Highest inhibitory rate was found against C. musae, C. gloeosporioides and C. papaya P.Henn, which was much stronger than that by tea saponin. Compared to tea saponin, effects of NSC extractum was relatively weak and similar on C. gloeosporioides Penzig and P. italicum. In an in vivo study, best controlling effects by NSC extractum was found with banana anthracnose disease development, which showed no inhibitory effects by tea saponin. NSC extractum controlled in vitro C. musae growth through directly inhibiting germination rate and germ tube elongation, and causing distortation, rupture and indentation of C. musae mycelium. In banana fruit subject to C. musae inoculation, higher PAL, POD, GLU and CHT activity was observed in banana fruit treated with crude NSC extractum than that of water control fruits. Current study proved the best controlling effects of crude NSC extractum in C. musae in vitro and in vivo development, which through direct inhibition of C. musae growth and increasing defense system of the banana fruit.

Characteristics of Self-excited Combustion Oscillation and Combustion Control by Forced Pulsating Mixture Supply

  • Yang, Young-Joon;Fumiteru Akamatsu;Masashi Katsuki;Lee, Chi-Woo
    • Journal of Mechanical Science and Technology
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    • v.17 no.11
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    • pp.1820-1831
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    • 2003
  • Characteristics of self-excited combustion oscillation are experimentally studied using confined premixed flames stabilized by a rearward-facing step. A new idea to suppress combustion oscillation was applied to the flames. The characteristics of unsteady combustion were examined, which is driven by forced pulsating mixture supply that can modulate its amplitude and frequency. The self-excited combustion oscillation having weaker flow velocity fluctuation intensity than that of the forced pulsating supply can be suppressed by the method. The effects of the forced pulsation amplitude and frequency on controlling self-excited combustion oscillations were also investigated comparing with the steady mixture supply. The unsteady combustion used in this experiment plays an important role in controlling self-excited combustion oscillations, and it also exhibits desirable performances, from a practical point of view, such as high combustion load and reduced pollutant emissions of nitric oxide.

Inactivation of Airborne E. coli and B. subtilis Bioaerosols Utilizing Thermal Energy

  • Lee, Yun-Ha;Lee, Byung-Uk
    • Journal of Microbiology and Biotechnology
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    • v.16 no.11
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    • pp.1684-1689
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    • 2006
  • Airborne microorganisms, which are currently termed bioaerosols, have received attention owing to the harmful effects they have on human health. As the concern over airborne microorganisms grows, there also grows an urgent need to study and develop efficient methods for controlling them. In this study, thermal energy using a thermal tube was tested as a control method, mainly against airborne E. coli. For a comparison, B. subtilis var. niger spores were utilized in the experimentation. It was found that the widely known inactivation conditions for microorganisms were not adequate against airborne microorganisms. The experimental results demonstrated the need for extensive studies that should investigate adequate and economic conditions to control against airborne bacteria. In this study, thermal energy exposed by the thermal tube demonstrated an inactivation performance for controlling E. coli bioaerosols.

Combustion Control and Symptom Detection on Self-excited Combustion Oscillation (자려 연소진동에 관한 연소제어와 징후의 검출)

  • Yang Young-Joon
    • Journal of Advanced Marine Engineering and Technology
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    • v.28 no.7
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    • pp.1111-1122
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    • 2004
  • An idea to suppress the self-excited combustion oscillation was applied to the flames. The characteristics of unsteady combustion were examined and the unsteady combustion was driven by forced pulsating mixture supply that can modulate its amplitude and frequency. The self-excited combustion oscillation having weaker flow velocity fluctuation intensity than that of the forced pulsating supply can be suppressed by this method. The effects of the forced pulsation amplitude and frequency on controlling self-excited combustion oscillations were also investigated comparing with the steady mixture supply. The unsteady combustion used in this experiment plays an important role in controlling self-excited combustion oscillation. Symptoms of self-excited combustion oscillation were also studied in order to predict the onset of combustion oscillation before it proceeded to a catastrophic failure For the purpose, the unique measures to observe the onset of self-excited combustion oscillations based on the careful statistics of fluctuating properties in flames, such as pressure or emission of OH radicals, have been proposed.

Effects of solution, sorbate, and sorbent chemistries on polycyclic aromatic hydrocarbon sorption to hydrated mineral surfaces

  • Yim, Soobin
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.132-135
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    • 2003
  • Solution chemistry, sorbate chemistry, and sorbent chemistry were widely investigated to find important factors that affect PAH sorption on mineral surfaces and to elucidate its microscopic mechanism. The solution chemistry, pH and ionic strength caused measurable change of HOC sorption reaction to minerals. The detectable change of Ka occurred at a pH region crossing the PZC (Point of Zero Charge) of each mineral. The PAH hydrophobicity, one of sorbate chemistry, was observed to have a strong correlation with PAM sorption to mineral. Mineral surface area was not found to be a predominant factor controlling PAH sorption. The mineral type might be more likely to play a crucial role in controlling the PAH sorption behavior. The CEC (Cation Exchange Capacity) of mineral, representing surface charge density, has meaningful correlation with regression slope of sorption coefficients (log $K_{d}$) versus aqueous activity coefficients (log Υ$_{w}$).).).

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Selection and Control Effect of Environmental Friendly Organic Materials for Controlling the Ginseng Alternaria Blight (인삼에 발생하는 점무늬병의 친환경적 방제를 위한 유기농업자재 선발 및 기 선발된 자재의 효과시험)

  • Kim, Woo Sik;Park, Jee Sung
    • Korean Journal of Medicinal Crop Science
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    • v.21 no.5
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    • pp.388-393
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    • 2013
  • This study was conducted to select environmental friendly organic materials for controlling the ginseng alternaria blight and to evaluate their effects from 2011 to 2012. Alternaria blight is caused by Alternaria panax and is the most common ginseng disease in Korea. Environmental friendly organic materials were used to reduce amount of chemical fungicides and the number of spray for control of Ginseng Alternaria leaf blight. In 4 years of ginseng, control value of Alternaria leaf blight by single application of Defenoconazole WP was 82.3% and those of single application was 62.0~75.9%. Consequently, mixed or alternated application of eco-material products could be recommended as a control method to reduce the amount of fungicides.

A Study on Method for Improving Reproducibility in the Ultrasonic Measurement of Bone Mineral Density (초음파 골밀도 측정에서 재현성 향상 방법에 관한 연구)

  • Shin, Jeong-Sik;Ahn, Jung-Hwan;Kim, Hwa-Young;Kim, Hyung-Jun;Han, Seung-Moo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.29 no.10 s.241
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    • pp.1430-1437
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    • 2005
  • It is very important to achieve a high reproducibility in the ultrasonic measurement of bone mineral density. In this study, we examined number of sampling waveform, control of temperature, diameter of region of interest as factors to improve reproducibility. We decided the optimal number of waveforms to be converted to frequency domain as period of 1. We have minimized the effects of variable temperature and constrained generation of micro bubble by keeping temperature within a range of $32\pm0.5^{\circ}C$ with a precise temperature controlling algorithm. We also found the optimal diameter of region of interest to be 13mm. In this paper, we demonstrated the improved reproducibility by controlling various factors affecting the ultrasonic measurement of bone mineral density.

Controlled Release of Drugs from Silicone Rubber Matrices-Effects of Physical Properties of Drugs and Release Controlling Agents on Drug Release Mechanisms- (실리콘 마트릭스로부터의 약물조절 방출-약물 및 방출조절제의 물성이 방출기전에 미치는 영향-)

  • Jeon, So-Young;Lee, Seung-Jin
    • Journal of Pharmaceutical Investigation
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    • v.21 no.4
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    • pp.237-245
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    • 1991
  • Matrix type silicone rubber devices were designed for long-term implantable drug delivery system. Release controlling agents (RCA), i.e., polypropylene glycol, polyethylene glycol, were employed to control drug release from the devices. The release rate of drug from RCA dispersed silicone matrices was mainly dependent on hydrophilicity-hydrophobicity of drug and RCA. In the case of hydrophilic drug, the release from the RCA dispersed matrix was regulated by swelling kinetics. Especially when the relatively hydrophobic polypropylene glycol was used, swelling control mechanism induced zero-order release kinetics. Whereas, the release of hydrophobic drug was resulted from partition mechanism. The effect of RCA was to increase drug diffusivity.

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