• Journal of Chest Surgery
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• v.23 no.3
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• pp.452-464
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• 1990

It is well known that extracellular Calcium plays a very important role in several steps of smooth muscle excitability and contractility, and there have been many concerns about factors influencing the distribution of extracellular Ca++ and the Ca++ flux through the cell membrane of the smooth muscle. Based on the assumption that Mg++ may also play an important role in the excitation and contraction processes of the smooth muscle by taking part in affecting Ca++ distribution and flux, many researches are being performed about the exact role of Mg++, especially in the vascular smooth muscle. But yet the effect of Mg++ in the smooth muscle activity is not clarified, and moreover the mechanism of Mg++ action is almost completely unknown. Present study attempted to clarify the effect of Mg++ on the excitability and contractility in the multiunit and unitary smooth muscle, and the mechanism concerned in it. The preparations used were the guinea-pig aortic strip as the experimental material of the multiunit smooth muscle and the rat uterine strip as the one of the unitary smooth muscle. The tissues were isolated from the sacrificed animal and were prepared for recording the isometric contraction. The effects of Mg++ and Ca++ were examined on the electrically driven or spontaneous contraction of the preparations. And the effects of these ions were also studied on the K+ or norepinephrine contracture. All experiments were performed in tris-buffered Tyrode solution which was aerated with 100% 02 and kept at 35oC. The results obtained were as follows: 1] Mg++ suppressed the phasic contraction induced by electrical field stimulation dose-dependently in the guinea-pig aortic strip, while the high concentration of Ca++ never recovered the decreased tension. These phenomena were not changed by the a - or b - adrenergic blocker. 2]Mg++ played the suppressing effect on the low concentration [20 and 40 mM] of K+-contracture in the aortic muscle, but the effect was not shown in the case of 100mM K+-contracture. 3] Mg++ also suppressed the contracture induced by norepinephrine in the aortic preparation. And the effect of Mg++ was most prominent in the contracture by the lowest [10 mM] concentration of norepinephrine. 4] In both the spontaneous and electrically driven contractions of the uterine strip, Mg++ decreased the amplitude of peak tension, and by the high concentration of Ca++ the amplitude of tension was recovered unlike the aortic muscle. 5] The frequency of the uterine spontaneous contraction increased as the [Ca++] / [Mg++] ratio increased up to 2, but the frequency decreased above this level. 6] Mg++ decreased the tension of the low[20 and 40mM] K+-contracture in the uterine smooth muscle, but the effect did not appear in the 100mM K+-contracture. From the above results, the following conclusion could be made. 1] Mg++ seems to suppress the contractility directly by acting on the smooth muscle itself, besides through the indirect action on the nerve terminal, in both the aortic and uterine smooth muscles. 2] The fact that the depressant effect of Mg++ on the K+-contracture is in inverse proportion to an increase of K+ concentration appears resulted from the extent of the opening state of the Ca++ channel. 3] Mg++ may play a depressant role on both the potential dependent and the receptor-operated Ca++ channels. 4] The relationship between the actions of Mg++ and Ca++ seems to be competitive in uterine muscle and non-competitive in aortic strip.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.6
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• pp.352-360
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• 2002

This study was carried out to find out the effect of Milk vetch(Astragalus sinicus L.) on growth, and yield of rice, physicochemical properties of soil, reduction rate of nitrogen fertilization, and soil improvement under the different plowing time with Milk vetch cultivated in paddy field, plowing at maximum blooming, last blooming, fruiting stages. The fresh weight of Milk vetch at each plowing time of maximum blooming, last blooming and fruiting stage was 22,500, 20,000, $12,500kg\;ha^{-1}$ respectively. Content of total nitrogen at three plowing times was 2.95, 2.66, and 2.47% and the C/N ratio were 15.7, 18.0, and 19.2, respectively. Physico-chemical properties of soil were improved in cultivated milk vetch, the content of T-N. OM and porosity ratio were increased while the content of $P_2O_5$ and bulk density, solidphase ratio were decreased compared to noncultivated milk vetch. Content of $NH_4-N$ in soil was highest plowing at maximum blooming stage and appeared an increasing tendency according to increased nitrogen level. Amount of nitrogen fertilizer by rice was highest plowing at maximum blooming stage and appeared an increasing tendency according to increased nitrogen level. Nitrogen-use efficiency was high in $33kg\;ha^{-1}$ nitrogen level at three plowing times. The number of spikelets per $m^2$ was high in plowing at maximum blooming stage, last blooming stage and the percentage of ripeness was high in fruiting stage of milk vetch. So the rice yield was increased 9%, 8% in $55kg\;ha^{-1}$ nitrogen level plowing at maximum blooming stage, last blooming stage and 1% in $77kg\;ha^{-1}$ nitrogen level plowing at fruiting stage compared to conventional cultivation.

• Journal of Food Hygiene and Safety
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• v.17 no.2
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• pp.61-70
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• 2002

In order to investigate the classification and antibiotic resistance of Salmonella species,718 isolates were isolated from patient in Seoul from 1996 to 2001. The two hundred and ninety eight isolates (41.5%) were identified as Sal. Enteritidis, followed by Sal. Typhi 218 isolates (30.4%), and Sal. Typhimurium 87 isolates (12.1%). The identified Salmonella species were most resistant to tetracycline (32.7%), followed by streptomycin (28.0%), ticarcillin (18.1%) and ampicillin (12.4%). Among isolates,34.7% of Sal. Enteritidis were resistant to tetracycline, 32.3% to streptomycin,23.2% to ticarcillin,13.5% to ampicillin, respectively. 13.8% of Sal. Typhi were resistant to streptomycin,10.6% to tetracycline, respectively.66.7% of Sal. Typhimurium were resistant to tetracycline, 42.5% to streptomycin, 28.7% to ticarcillin, 26.4% to ampicillin and 17.2% to chloramphenicol, respectively. Of 718 isolates, 324 isolates (45.1%) were resistant to 1 or more drugs and 64 isolates (19.8%) were resistant to 1 drug, 132 isolates (40.7%) were resistant to 2 drugs,50 isolates (15.4%) were resistant to 3 drugs, 27 isolates (8.3%) to 4 drugs,27 isolates (8.3%) to 5 drugs,22 Isolates (6.8%) to 6 drugs. The most prevalent multiple resistant pattern was tetracycline-kanamycin (35.5%), followed by tetracycline-kanamycin-ticarcillin (8.3%), and tetracycline-kanamycin-ticarcillin-ampicillin (7.4%) . Antibiotic resistant rate of Sal. Typhimurium was 73.6%,1311owe4 by Sal. Enteritidis 53.7% and Sal. Typhi 19.3%. Most Sal. Enteritidis was resistant to 1 drug o.2 drugs, whereas Sal. Typhi. and Sal.. Typhunurium were more .resistant to 5 (16.7%) or 6 drugs (26.6%). The old generation antibiotics such as ampicillin, tetracycline, and streptomycin were annually more resistant than the new generation antibiotics such as ceftriaxone, ciprofloxacin or cefoxitin.

• Food Science of Animal Resources
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• v.28 no.4
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• pp.422-430
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• 2008

This study was conducted to investigate the nutritional composition and meat quality properties of Hanwoo steer beef by different cut. Ten cuts [Abjin (short plate), Bosup (top sirloin), Cheggt (striploin), Dngsim (loin), Guri (chuck tender), Hongduke (eye of round), Moksim (chuck roll), Sulgit (bottom round), Udoon (top round), Yanaji (brisket)] prepared from 10 Hanwoo steers (28-30 months old) were used for this experiment. The range of pH was 5.46-5.64. In the chemical analysis, Hongduke contained highest protein contents (21.15%) and Dngsim had lowest protein contents (16.94%) (p<0.05). Fat contents were higher in Dngsim whereas those of Guri, Hongduke and Udoon were significantly lower when compared to the other cuts (p<0.05). There were not significantly different in meat color (L, a and b values) properties only except that L values were significantly higher in Dngsim among 10 cuts (p<0.05). Cooking loss (%) was higher in Guri, Hongduke, Udoon and Yangji whereas it was significantly love. in Cheggt (p<0.05). Warner-Bratzler shear force (WBS) was significantly higher in Abjin $(6.24inch^2/kg)$, whereas Dngsim $(3.45inch^2/kg)$ and Cheggt $(3.50inch^2/kg)$ were significantly lower than the other cuts (p<0.05). There was no significant difference in water-holding capacity (WHC) among 10 cuts (p>0.05). Total amino acid contents were significantly higher in Hongduke (p<0.05). Hongduke was highest in most kinds of amino acids, however, Udoon had the highest methionine and histidine contents among 10 cuts (p<0.05). Glutamate contents were high in all cuts and followed by aspartate, leucine and lysin. With regard to mineral contents, Ca was ranged from 47.63-70.69 mg/kg and Fe was ranged from 15.09-26.68 mg/kg in 10 cuts. Zn was highly contained in Guri (50.56 mg/kg) when compared to the other cuts (p<0.05).

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.507-513
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• 2001

An effective extraction methods of a garlic were investigated in order to improve the functional properties of the extracts. The solid yield, electron donating ability (EDA), nitrite-scavenging effects (NSE), peroxide value (POV) and total thiosulfinates contents of garlic extracts were determined. In order to improve the functional properties of extracts prepared with several organic solvents and acids, concentration and pH adjustment of the selected solvent and addition of acids and salts to solvents were also examined. Among the solvents tested, the methanol and ethanol extracts were found to be the most effective on the base of functionality and solid yields. The highest EDA, NSE and thiosulfinate value were obtained with 50% ethanol. The pH control of solvent and addition of citric acid, NaCl and phosphates to 50% ethanol did not affect on the functionality of the extracts. Therefore the optimal solvent for the best functional properties of garlic extract was 50% ethanol.

• Resources Recycling
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• v.17 no.1
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• pp.80-87
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• 2008

Cementation and solvent extraction processes were studied to separate nickel and iron ions from the $H_2SO_4$ leaching solution with 47 g/L $Fe(Fe^{2+}/Fe^{3+}=1.03),$, 23.5 g/L Ni and 0.90M $H_2SO_4$ which leached from Fe-Ni alloy. Iron powder was used as a reducing agent for the cementation of Ni ion from the leaching solution. The reduction percentage of Ni ion was $17{\sim}20%$ by adding 4 times stoichiometric amount of iron powder at $60{\sim}80$. This may result from the fact that the cementation of Ni ion occurred after the reduction of $Fe^{3+}$ to $Fe^{2+}$ and the neutralization of $H_2SO_4$ with iron powder. The cementation process was proved to be unfeasible for the separation/recovery of Ni ion from the leaching solution including $Fe^{3+}$ as a major component. $Fe^{2+}$ present in the leaching solution was converted to $Fe^{3+}$ for solvent extraction of Fe ion using D2EHPA in kerosene as a extractant. The oxidation of $Fe^{2+}$ to $Fe^{3+}$ was completed by the addition of 1.2 times stoichiometric amount of 35% $H_2SO_4$. 99.6% $Fe^{3+}$ was extracted from the leaching solution (23.5 g/L $Fe^{3+}$) by 4 stages cross-current extraction using 20 vol.% D2EHPA in kerosene. $NiSO_4$ solution with 98.5% purity was recovered from the $H_2SO_4$ leaching solution of scrapped Fe-Ni alloy.

• Journal of agriculture & life science
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• v.46 no.3
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• pp.97-108
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• 2012

Physical, chemical and biological hazards of strawberry farms at the cultivation stage were analyzed to establish the GAP(Good Agricultural Practice) system. Samples were collected from the plants, cultivation environments(water, soil and air), and personal hygiene (hand, glove, and clothes) of three strawberry farms(A, B, and C) and were tested to analyze physical, chemical (heavy metals and pesticide residues), and biological(sanitary indications and foodborne pathogens) hazards. Physical hazards such as insects and pieces of metal and glass were found in the strawberry farms and can be potential bow for strawberry products. Heavy metal and pesticide residue as chemical hazards were detected at levels lower than the regulation limit. In case of biological hazards, total bacteria and coliform were detected at the levels of 1.6~7.3 and 1.3~5.6 log CFU/g, leaf, mL, hand or $100cm^2$. However, Escherichia coli was not detected in all samples. Bacillus cereus and Staphylococuus aureus were detected at levels of ${\leq}$ 1.1~6.1 log CFU and 4.7~5.4 log CFU/g, mL, hand or $100cm^2$, whereas Listeria monocytogenes, E. coli O157 and Salmonella spp. were not detected in all samples. This study demonstrates that various harzards were in strawberry farms at the growing stage. Therefore proper management such as GAP is needed to prevent the occurrence of food poisoning associated with the hazards revealed in this study.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.141-153
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• 2012

Samples collected from six tomato farms(A, B, C : soil culture, D, E, F : Nutriculture) located in Gyeongsangnam-do were tested for the analyses of biological(sanitary indications, major foodborne pathogens, fungi), chemical(heavy metals, pesticides) and physical hazards. The highest levels of total bacteria(7.5 log CFU/g) and coliforms(5.0 log CFU/g) in soil culture farms were higher than those of nutriculture farms(total bacteria: 2.5 log CFU/mL, coliforms: 0.6 log CFU/mL). In crops and personal hygiene soil culture farms showed a slightly higher contamination levels. From all farms, the levels of fungi in soil farms were higher than those of nutrient solution. In case of major pathogens, Bacillus cereus and Staphylococcus aureus were detected in all sample with the exception of nutrient solution. Meantime, Escherichia coli, Listeria monocytogenes, E.coli O157 and Salmonella spp. were not detected. For airborne bacteria, soilculture farms showed less contamination than nutriculture farms. A piece of glass and can was confirmed asphysical hazards. Heavy metal(Cd, Pb, Cu, Cr, Hg, Zn, Ni and As) and pesticide residues as chemical hazards were detected, but their levels were lower than the regulation limit. These results demonstrate that potential hazards on harvesting stage of tomato fam were exposed. Therefore, proper management is needed to prevent biological hazards due to cross-contamination, while physical and chemical hazards were in appropriate levels based on GAP criteria.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.399-407
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• 2009

Laser induced breakdown spectroscopy(LIBS) is an simple analysis method for directly quantifying many kinds of soil micro-elements on site using a small size of laser without pre-treatment at any property of materials(solid, liquid and gas). The purpose of this study were to find an optimum condition of the LIBS measurement including wavelengths for quantifying soil elements, to relate spectral properties to the concentration of soil elements using LIBS as a simultaneous un-breakdown quantitative analysis technology, which can be applied for the safety assessment of agricultural products and precision agriculture, and to compare the results with a standardized chemical analysis method. Soil samples classified as fine-silty, mixed, thermic Typic Hapludalf(Memphis series) from grassland and uplands in Tennessee, USA were collected, crushed, and prepared for further analysis or LIBS measurement. The samples were measured using LIBS ranged from 200 to 600 nm(0.03 nm interval) with a Nd:YAG laser at 532 nm, with a beam energy of 25 mJ per pulse, a pulse width of 5 ns, and a repetition rate of 10 Hz. The optimum wavelength(${\lambda}nm$) of LIBS for estimating soil and plant elements were 308.2 nm for Al, 428.3 nm for Ca, 247.8 nm for T-C, 438.3 nm for Fe, 766.5 nm for K, 85.2 nm for Mg, 330.2 nm for Na, 213.6 nm for P, 180.7 nm for S, 288.2 nm for Si, and 351.9 nm for Ti, respectively. Coefficients of determination($r^2$) of calibration curve using standard reference soil samples for each element from LIBS measurement were ranged from 0.863 to 0.977. In comparison with ICP-AES(Inductively coupled plasma atomic emission spectroscopy) measurement, measurement error in terms of relative standard error were calculated. Silicon dioxide(SiO2) concentration estimated from two methods showed good agreement with -3.5% of relative standard error. The relative standard errors for the other elements were high. It implies that the prediction accuracy is low which might be caused by matrix effect such as particle size and constituent of soils. It is necessary to enhance the measurement and prediction accuracy of LIBS by improving pretreatment process, standard reference soil samples, and measurement method for a reliable quantification method.

• Journal of Korean Philosophical Society
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• v.129
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• pp.167-191
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• 2014

Pour Kierkegaard la condition de l'homme naturel est tragique. $D^{\prime}{\hat{e}}tre$ $s^{\prime}{\acute{e}}veiller$, ${\hat{e}}tre$ ignorant et $d{\acute{e}}nier$ sur son vrai ${\hat{e}}tre$, tous causent le $d{\acute{e}}sespoir$. En plus l'homme ne peut avoir une conviction sur son bonheur $jusqu^{\prime}{\grave{a}}$ la mort. Donc sa $th{\acute{e}}orie$ du bonheur ne se base pas sur le bonheur. Tous le monde vit dans une situation $o{\grave{u}}$ il y a une distance entre $l^{\prime}{\hat{e}}tre$ $pr{\acute{e}}sent$ et son vrai ${\hat{e}}tre$. La vie ${\grave{a}}$ la perspective ${\acute{e}}thique$ s'apparaît comme se diriger vers son vrai ${\hat{e}}tre$ et ceci signifie $d^{\prime}{\acute{e}}tablir$ son ${\hat{e}}tre$ $int{\acute{e}}rieur$ en s'echappant la vie $esth{\acute{e}}tique$ qui est la vie sensitive et directe, et aussi faire s'identifier son ${\hat{e}}tre$ $ext{\acute{e}}rieur$ ${\grave{a}}$ son ${\hat{e}}tre$ $int{\acute{e}}rieur$. Le $p{\acute{e}}ch{\acute{e}}$ signifie la $s{\acute{e}}paration$ de son vrai ${\hat{e}}tre$, cela est la source de tout mal. L'obtention parfait de $l^{\prime}{\hat{e}}tre-soi$ exisge ${\hat{e}}tre$ en $pr{\acute{e}}sence$ devant l'Asolu(Dieu) en tant qu'individu unique, et s'accorder avec l'Absolu. Mais du fiat $m{\hat{e}}me$ que ceci est impossible pour tous, tout le monde ne peut vivre qu'ayant un peu de $p{\acute{e}}ch{\acute{e}}$. Donc l'aspect de la vie ${\acute{e}}thique$ s'apparaît une vie dynamique qui $d{\acute{e}}passe$ $soi-m{\hat{e}}me$ sans cesse. En contradiction qu'avec l'analyse sur $l^{\prime}{\hat{e}}tre$ $pr{\acute{e}}sent$ qui est si tragique, la vertu de cette vie ${\acute{e}}thique$ est si optimiste. Elle est l'amour. Cet amour est $tr{\acute{e}}s$ excellent qui $d{\acute{e}}passe$ toute la vertu ${\acute{e}}thique$. En $v{\acute{e}}rit{\acute{e}}$ pour Kierkegaard, bien que le salut $lui-m{\hat{e}}me$ sera donner par la foi, le principe de cet amour est l'unique vertu qui ammene l'homme vers la foi et vers le salut. C'est pourquoi son ${\acute{e}}thique$ est essentiellement s'apparaît 'une ${\acute{e}}thique$ de l'amour', et la recherche sur cet amour, son principe et son aspect reste comme uneque $t{\hat{a}}che$ de $l^{\prime}{\acute{e}}thique$.