• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.5
• /
• pp.364-370
• /
• 2009

This study was conducted to survey, analyze on the compaction layer and the plow layer at Jeonbug and Jisan series paddy soil, which is the representative soil in fluvio-marine and local alluvium, respectively. The depths of surface soil were 12.6 and 12.7 cm in Jeonbug and Jisan series, respectively. A plowing depth was 10.5 cm. The properties of compaction layer in two soil series were as follows. The hardness were $14.7kg\;cm^{-2}(25.3mm)$ and $8.7kg\;cm^{-2}(22.1mm)$ in Jeonbug and Jisan series, respectively. The thickness were 22.3 cm and 17.8 cm in Jeonbug and Jisan series, respectively. The depth of soil compaction, which means depth from surface, were 15 and 20 cm in Jeonbug and Jisan series, respectively. The relationship between the hardness of compaction layer and the depth of surface soil showed negative correlation, however relationship between the hardness and the thickness of compaction layer showed positive correlation. Soil temperature was lower in compaction layer than in plow layer. This temperature differences between compaction layer and plow layer were from 1.0 to $2.5^{\circ}C$ in Jeonbug series and from 0.7 to 2.1 in Jisan series. The soil physical properties of compaction layer were higher in bulk density and solid phase and lower in porosity and gaseous phase than those of plow layer in all soil series. The soil chemical properties of compaction layer were higher in pH, content of available silicate, exchangeable calcium and magnesium but lower in total nitrogen, content of organic matter and available phosphate than those of plow layer in all soil series. Cation exchangeable capacity and content of exchangeable potassium were similar between compaction layer and plow layer in Jeonbug series, however, in Jisan series these were lower in compaction layer than in plow layer. Elution amount of inorganic nitrogen were lower in compaction layer than in plow layer in all soil series. The content of soluble Fe and Mn were plenty in compaction layer compared with plow layer and these tendency was apparent in Jeonbug series. The water depth decrease were fast until the latter part of June, and were slow as $1{\sim}3mm\;day^{-1}$ for July and August, and were fast again from september. Rice roots distributions as each soil series and tillage method were 25 cm at rotary plowing in Jeonbug series, 30 cm at deep plowing in Jeonbug series, and 20 cm at tillage in Jisan series. Dry weight per m2 at heading stage were much in order of deep plowing in Jeonbug series, rotary plowing in Jeonbug series, and tillage in Jisan series.

• YAKHAK HOEJI
• /
• v.54 no.6
• /
• pp.461-465
• /
• 2010

We investigated the role of L-type $Ca^{2+}$ channel in receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast formation. BayK 8644, a L-type $Ca^{2+}$ channel agonist, was shown to increase the RANKLinduced osteoclastogenesis and actin ring formation in mouse bone marrow-dereived macrophage (BMM) culture system. BayK 8644 stimulated RANKL-induced extracellular signal-regulated kinase (ERK) and p38 MAP kinase (MAPK) activation, which leads to increased nuclear factor of activated T cells (NFAT)c1 expression. Taken together, these data indicate that L-type $Ca^{2+}$ channel regulates osteoclast formation possibly through ERK- and p38-mediated NFATc1 expression.

• The Korean Journal of Pain
• /
• v.20 no.2
• /
• pp.92-99
• /
• 2007

Background: A correlation between a T-type voltage activated calcium channel (VACC) and pain mechanism has not yet been established. The purpose of this study is to find out the effect of ethosuximide and mibefradil, representative selective T-type VACC blockers on postoperative pain using an incisional pain model of rats. Methods: After performing a plantar incision, rats were stabilized on plastic mesh for 2 hours. Then, the rats were injected with ethosuximide or mibefradil, intraperitoneally and intrathecally. The level of withdrawal threshold to the von Frey filament near the incision site was determined and the dose response curves were obtained. Results: After an intraperitoneal ethosuximide or mibefradil injection, the dose-response curve showed a dose-dependent increase of the threshold in a withdrawal reaction. After an intrathecal injection of ethosuximide, the threshold of a withdrawal reaction to mechanical stimulation increased and the increase was dose-dependent. After an intrathecal injection of mibefradil, no change occurred in either the threshold of a withdrawal reaction to mechanical stimulation or a dose-response curve. Conclusions: The T-type VACC blockers in a rat model of postoperative pain showed the antihyperalgesic effect. This effect might be due to blockade of T-type VACC, which was distributed in the peripheral nociceptors or at the supraspinal level. Further studies of the effect of T-type VACC on a pain transmission mechanism at the spinal cord level would be needed.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.36 no.3
• /
• pp.404-411
• /
• 2009

Drinking water has lots of minerals, especially calcium, sodium, kalium, magnesium, and fluoride must be labelled on the bottle about their contents. Minerals like calcium, magnesium, and fluoride have influence to the tooth development. Appropriately taking some minerals, dental caries can be prevented somewhat degree. There is no guide line about innoxious minerals like calcium and magnesium, however, noxious mineral like fluoride, should be contained less than 2 mgF/L according to the current drinking water standard. Hereupon, it is necessary to recognize the concentration of fluoride in drinking water, so I studied 15 samples of domestic drinking water on sale about the concentration of calcium and magnesium, fluoride. The results obtained were as follows ; 1. 14 drinking waters in 15 samples showed various Ca concentration. The average Ca concentration is 34.68${\pm}$31.84 mg/L, the highest is 128.91${\pm}$1.85 mg/L and the lowest is 2.0${\pm}$0.02 mg/L. 2. 13 drinking waters in 15 samples indicate the Mg concentration. The average concentration is 9.22${\pm}$11.06 mg/L, the highest is 30.43${\pm}$0.75 mg/L and the lowest is 0.0 mg/L. 3. 11 drinking waters in 15 samples indicate the F concentration. The average concentration is 0.25${\pm}$0.33 mg/L, the highest is 1.13${\pm}$0.04 mg/L and the lowest is 0.01${\pm}$0.03 mg/L. All samples are satisfied the current drinking water standard, 2 mg F/L.

• Journal of Biosystems Engineering
• /
• v.9 no.2
• /
• pp.74-80
• /
• 1984

Storage materials for a minimized storage system should be able to store much energy in small quantities, and to solve such a problem, salt hydrates such as CALCIUM CHLORIDE, SODIUM SULFATE, SODIUM PHOSPHATE etc. were considered as most suitable storage media in which phase change phenomena take place at low temperature. Therefore those salt hydrates were used as storage media in this study, and piped-storage tanks were manufactured vertically for the experiment. The characteristics of thermal storage media were investigated and the results are summarized as follows: 1. From the experiment of radial temperature distribution of vertical piped-storage system, the latent heat phenomenon did not occur in all storage media during heating process because of generations of heat due to the reduction in the number of water molecules. However, among those storage media CALCIUM CHLORIDE had most remarkable latent heat phenomenon during cooling process. Therefore CALCIUM CHLORIDE was considered as most suitable storage media. 2. Heat quantity transferred to the storage media was the largest in case of CALCIUM CHOLORIDE under the same conditions during heating and cooling process.

• YAKHAK HOEJI
• /
• v.59 no.4
• /
• pp.177-183
• /
• 2015

The mechanism of melanogenesis induced by cyclosporin A (CsA) was investigated in B16 melanoma cells. CsA stimulated the production of melanin in a dose-dependent manner in the cells. In addition, CsA increased intracellular $Ca^{2+}$ concentration in a dose-related fashion. Treatment with BAPTA/AM, an intracellular $Ca^{2+}$ chelator significantly inhibited the CsA-induced intracellular melanin synthesis. CsA profoundly induced $Cl^-$ efflux, which was significantly blocked by niflumic acid (NFA) and flufenamic acid (FFA), specific and nonspecific inhibitors of $Ca^{2+}$-activated $Cl^-$ channels (CaCCs), respectively. Furthermore, these inhibitors of CaCCs significantly inhibited the CsA-induced stimulation of melanin synthesis. Taken together, these results suggest that the activation of CaCCs may play an important role in the CsA-induced stimulation of melanin synthesis in B16 cells. These results further suggest that CaCCs may be a good target for the management of hyperpigmentation of the skin reported in the patients treated with CsA.

• Journal of The Korean Society of Clinical Toxicology
• /
• v.18 no.1
• /
• pp.1-10
• /
• 2020

Pharmaceutical agents are the most common causes of poisoning in Korea. Calcium channel blockers (CCBs) are commonly used in Korea for the management of hypertension and other cardiovascular diseases, but are associated with a risk of mortality due to overdose. Due to the frequent fatalities associated with CCB overdose, it is essential that the emergency physician is capable of identifying CCB intoxication, and has the knowledge to manage CCB overdose. This article reviews the existing clinical guidelines, retrospective studies, and systematic reviews on the emergency management of CCB overdose. The following are the varied treatments of CCB overdose currently administered. 1) For asymptomatic patients: observation with enough time and decontamination, if indicated. 2) For symptomatic patients: infusion of calcium salt, high dose insulin therapy, and vasopressor (norepinephrine) or atropine for bradycardia. 3) For patients refractory to the first line therapy or with refractory shock or impending arrest: lipid emulsion therapy and extracorporeal membrane oxygenation. 4) As adjunct therapy: phosphodiesterase inhibitors, glucagon, methylene blue, pacemaker for AV block. Small CCB ingestion is known to be fatal for pediatric patients. Hence, close observation for sufficient time is required.

• Journal of Urban Science
• /
• v.9 no.2
• /
• pp.45-50
• /
• 2020

The formation characteristics of calcium carbonates are closely related to the durability and mechanical properties of cement-based materials. In this regard, a deep understanding of the reaction pathway of calcium carbonates is critical. Recently, non-classical nucleation theory was summarized and it was presumed that prenucleation clusters are present. The formation of the prenucleation cluster at undersaturated condition (≈ 0.1 ml) in the present study was investigated via electrical characteristics of an electrolytic solution. Calcium chloride dihydrate (CaCl2·2H2O) and sodium carbonate (Na2CO3) were used as starting materials to supply calcium and carbonate sources, respectively. Furthermore, the reaction pathway of calcium carbonates was investigated by time-resolved polarization and depolarization characteristics of the electrolytic solution. The time-resolved polarization and depolarization tests were conducted by switching polarity with an interval of 20 seconds for 1 hr and by measuring the variation of electrical resistance. It can be inferred from the results obtained in the present study that the reactive constituent for the formation of calcium carbonates was mostly consumed in the period possibly associated with the prenucleation and the reaction pathways may be governed by the monomer-addition mechanism.

• The Korean Journal of Pharmacology
• /
• v.25 no.1
• /
• pp.53-58
• /
• 1989

For several years, we investigated the pharmacological action of several substances isolated from Buxus microphylla var koreana Nakai, which had been used as folk remedies of malaria and venereal disease. Cyclobuxine $D(C_{25}H_{42}ON_2)$, a steroidal alkaloid, exerted an antiinflammatory action, hypotensive and bradycardic effects in rats. In the present study, we isolated alkaloid from the acetone-insoluble fraction of the strong bases of this plants. This alkaloid $(C_{25}H_{38}ON_2)$ was identified as a steroidal alkaloid contained a cyclopropane ring by physical and chemical methods. It is a derivative of cyclobuxine D and named cyclobuxine E. We examined the effect of cyclobuxine E on the contractile response induced by acetylcholine and two distinct types of potassium-activated calcium channels in an intestinal smooth muscle of the rat. Cyclobuxine E inhibited significantly the Ach-induced contraction. The isolated longitudinal muscle from the rat duodenum was immersed calcium-depleted potassium depolarizing solution. Ten minutes after, 1.8 mM $CaCl_2$ was added to muscle bath and elicited a biphasic increase in muscle tension. Cyclobuxine E produced an appreciable inhibition of both components of the mechanical response. In addition, Cyclobuxine E introduced at a point when the tonic response had reached its maximum level, caused the muscle to exhibit a rapid loss of tension. Based on these experimental results, we proposed the possibility that the inhibitory action of cyclobuxine E on the isolated rat duodenum may be due to inhibiting the transmembrane fluxes of calcium ion in potassium-activated calcium channels.

• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1981.05a
• /
• pp.11.2-11
• /
• 1981

Compared with other medical parts, there are relatively rare cases of the calculi in the Otolaryngologic field. The authors have recently experienced cases of the tonsillolith and huge rhinolith. They were removed successfully under the local anesthesia. Small quantities of calcareous or gritty particles are often found in the center of the caseous plugs filling the crypts of the tonsil in chronic follicular tonsillitis. The patients usually give a history of repeated tonsillitis in the earlier years. The patient may be aware of a constant sensation as of a foreign body in the throat. The breath is often fetid. The tonsillar calculi was found to be the accumulated keratohyalin masses in the crypts. The rhinoliths are rare in nasal cavity. They usualy have a foreign body nucleus of bacteria, blood, pus cells, mucus, crusts, or some foreign material from outside the body. They are largely composed of calcium and magnesium salts, principally carbonate with traces of sodium chloride. The condition is commonly found in adults and in female. They are usualy unilateral and are located, in the majority of instances, in the lower portion of the nasal cavity. The first well documented cases of rhinolithiasis, however, were reported by Bartholin in 1654. Since then over 400 cases have been reported.