• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 1998.06a
• /
• pp.50-69
• /
• 1998

Dimethomorph is a novel fungicide with a high level of activity against diseases induced by certain Oomycetes, including fungal populations that are resistant to other products. In several ways, this fungicide illustrates the opportunities and challenges presented by many modern pesticides. The specific mode of action, which affects cell wall formation, is associated with a very high level of performance and low dose rates under field conditions. These low dose rates, combined with a low level of toxicity to non-target organisms present an outstanding safety profile. This same highly-specific mode of action, however, limits the spectrum of activity and suggests the need for a resistance management plan, both of which must be addressed in new product development. In addition, the biological and physiochemical properties of this, and other new products are not adequately described by the traditional classification of fungicides into“protectant”and“systemic”types. These unique profiles provide novel and useful products for disease control.

• The Korean Journal of Physiology and Pharmacology
• /
• v.5 no.5
• /
• pp.389-396
• /
• 2001

Neuroprotective properties of lithium were investigated by using in vivo NMDA excitotoxicity model. The appearance of TUNEL positive cells was prominent within 24 h of NMDA (70 mg/kg, i.p.) injection in the regions of the cortex, hippocampal formation, and thalamus of mouse cerebrum. NMDA treatment resulted in the extensive enhancement of Bax immunoreactivity in the cortical and hippocampal regions. NMDA also increased the immunoreactivity of caspase 8 in the similar regions of the mouse cerebrum. However, the increased immunoreactivity of Bax and caspase 8 were dramatically attenuated by chronic lithium pretreatment (lithium chloride, 300 mg/kg/d, i.p. for $7{\sim}10$ days). At the same time, lithium ion blocked the appearance of TUNEL positive cells, and the morphological assessment indicated an effective neuroprotection by lithium against NMDA excitotoxicity. Although the exact action mechanism of lithium is not straightforward at this time, we propose that the inhibition of Bax and caspase cascade is involved in the neuroprotective action of lithium.

• Natural Product Sciences
• /
• v.2 no.1
• /
• pp.24-28
• /
• 1996

The antiinflammatory and analgesic activities of higenamine were evaluated by measuring edema volume and pain threshold in adjuvant arthritic rats and acetic acid-induced writhing test in mice. Higenamine, with consecutive oral administrations at doses of 10 and 50 mg/kg/day, showed significant antiedemic effect and elevation of pain threshold during the secondary lesion of adjuvant arthritis. Higenamine also showed a significant inhibition of acetic acid-induced writhing syndrome with a single oral administration (200 mg/kg). From these results, it is postulated that higenamine might possess both of centrally and peripherally mediated analgesic properties.

• Journal of Electrochemical Science and Technology
• /
• v.6 no.1
• /
• pp.7-15
• /
• 2015

3-(4-Iodophenyl)-2-imino-2,3-dihydrobenzo[d]oxazol-5-yl 4-methylbenzenesulfonate (4-IPhOXTs) was synthesized and its inhibiting action on the corrosion of stainless steel 316L (SS) in sulfuric acid was investigated by means of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results of the investigation show that this compound has excellent inhibiting properties for SS corrosion in sulfuric acid. Inhibition efficiency increases with increase in the concentration of the inhibitor. The adsorption of 4-IPhOXTs onto the SS surface followed the Langmuir adsorption model with the free energy of adsorption ΔG⁰_ads of −8.45 kJ mol⁻¹ . Quantum chemical calculations were employed to give further insight into the mechanism of inhibition action of 4-IPhOXTs.

• Korean Journal of Microbiology
• /
• v.18 no.3
• /
• pp.133-147
• /
• 1980

Washed mycelia of Aspergillus nidulans FGSC159 were incubated in CMC minimal liquid medium and the culture filtrate which contained induced extracellular cellulase was fractionated by a three-step procedure including chromatography on Bio-Gel P-150, chromatography on DEAE-Sephadex A-50 and chromatography on Sephadex G-100. Three CMCase components ; F-I-Ia, F-I-Ib and F-II-Ia were prepared. No enzyme activity toward avicel could be detected in these components. Similarly, there was no ${\beta}-glucosidase$ activity. pH-optima of the three components were all 5.0 in acetate buffer. Temperature-optima for the activities of F-I-Ia, F-Ib and F-II-Ia were $45^{\circ}C,\;40^{\circ}C\;and\;50^{\circ}C$, respectively. F-II-Ia was shown to be more thermostable than the other two components. F-II-Ia was proved to have quite a different substrate specificity and action property and action property from those of F-I-Ia and F-I-Ib by product analysis on liquid chromatography.

• Bulletin of the Korean Mathematical Society
• /
• v.26 no.1
• /
• pp.1-9
• /
• 1989

In 1980 and 1983, it was proved that P $D^{2}$-groups are surface groups ([2], [3]). Since then, topologists have been positively studying about P $D^{n}$ -groups (or $D^{n}$ -groups). For example, let a topological space X have a right .pi.-action, where .pi. is a multiplicative group. If each x.memX has an open neighborhood U such that for each u.mem..pi., u.neq.1, U.cap. $U_{u}$ =.phi., this right .pi.-action is said to be proper. In this case, if X/.pi. is compact then (1) .pi.$_{1}$(X/.pi).iden..pi.(X:connected, .pi.$_{1}$: fundamental group) ([4]), (2) if X is a differentiable orientable manifold with demension n and .rho.X (the boundary of X)=.phi. then $H^{k}$ (X;Z).iden. $H_{n-k}$(X;Z), ([6]), where Z is the set of all integers.s.

• Advances in concrete construction
• /
• v.7 no.3
• /
• pp.191-201
• /
• 2019

Bamboo concrete bond behaviour is investigated through pullout test in this work. The bamboo strip to be used as reinforcement inside concrete is first treated with chemical adhesive to make the bamboo surface impermeable. Various surface coatings are explored to understand their water repellant properties. The chemical action at the bamboo concrete interface is studied through different chemical coatings, sand blasting, and steel wire wrapping treatment. Whereas mechanical action at the bamboo concrete interface is studied by developing mechanical interlock. The result of pullout tests revealed a unique combination of surface treatment and grooved bamboo profile. This combination of surface treatment and a grooved bamboo profile together enhances the strength of bond. Performance of a newly developed grooved bamboo strip is verified against equivalent plain rectangular bamboo strip. The test results show that the proposed grooved bamboo reinforcement, when treated, shows highest bond strength compared to treated plain, untreated plain and untreated grooved bamboo reinforcement. Also, it is observed that bond strength is majorly influenced by the type of surface treatment, size and spacing of groove. The changes in bamboo-concrete bond behavior are observed during the experimentation.

• Fibers and Polymers
• /
• v.7 no.4
• /
• pp.389-397
• /
• 2006

The beneficial effects of graduated compression stockings (GCS) in prophylaxis and treatment of venous disorders of human lower extremity have been recognized. However, their pressure functional performances are variable and unstable in practical applications, and the exact mechanisms of action remain controversial. Direct surface pressure measurements and indirect material properties testing are not enough for fully understanding the interaction between stocking and leg. A three dimensional (3D) biomechanical mathematical model for numerically simulating the interaction between leg and GCS in dynamic wear was developed based on the actual geometry of the female leg obtained from 3D reconstruction of MR images and the real size and mechanical properties of the compression stocking prototype. The biomechanical solid leg model consists of bones and soft tissues, and an orthotropic shell model is built for the stocking hose. The dynamic putting-on process is simulated by defining the contact of finite relative sliding between the two objects. The surface pressure magnitude and distribution along the different height levels of the leg and stress profiles of stockings were simulated. As well, their dynamic alterations with time processing were quantitatively analyzed. Through validation, the simulated results showed a reasonable agreement with the experimental measurements, and the simulated pressure gradient distribution from the ankle to the thigh (100:67:30) accorded with the advised criterion by the European committee for standardization. The developed model can be used to predict and visualize the dynamic pressure and stress performances exerted by compression stocking in wear, and to optimize the material mechanical properties in stocking design, thus, helping us understand mechanisms of compression action and improving medical functions of GCS.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1997.04a
• /
• pp.3-5
• /
• 1997

Properties of a good drug include safety, efficacy, half-life and bioavailability. With the current approach to drug discovery based on receptor-based and cell-based screening methods, compounds are frequently moved into development with poor bioavailability. With low bioavailability, drug administration is typically limited to parenteral routes, thus limiting the potential wide-spread utility of these therapeutic agents. The first and most important factor limiting a drug's bioavailability is the intestinal membrane permeability which in turn determines the maximum fi:action of the dose administered that can be absorbed. We have recently utilized new intubation methods for performing permeability measurements in humans and establishing a fundamental human data base for correlating intestinal jejunal membrane permeabilities with permeabilities determined in other systems, e.g., animals, tissue culture, as well as physical chemical properties.

• Archives of Pharmacal Research
• /
• v.17 no.5
• /
• pp.304-308
• /
• 1994

Among the new series of phenylacetamides, one of capsaicin derivatives, KR-25018 was found to have a very potent analgesic activity. Thus, the phamacological properties of KR-25018 were compared with those of morphine, capsaicin, and nonsteroidal antiinflammatory drugs (NSAIDs). The analgesic activities were evaluated in several animal models, using different stimuli, such as phenylbenzoquinone(PBQ)-induced weithing test, tail-filck test in mice and adjuvant arthritic flexion test in rat. The relationship of phamacological properties of KR-25018 to that of centrally acting opioids was assessed by the blocking test using naloxone. The analgesic potency of the KR-25018 $(MPED_{50}=0.89{\;}p.o.{\;}in{\;}PBQ-induced{\;}weithing{\;}test, {\;}MPED_{50}$=0.61$ s.c. in tail-flick test in mice0, with different action mechanism from morphine and NSAIDs, was comparable to that of morphine.