• Journal of the Korean Society of Food Science and Nutrition
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• 제38권3호
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• pp.346-351
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• 2009

This study was carried out to determine the rheological properties of bread doughs containing flour-ferments prepared with seed mash obtained by Koji incubation, yeast, and lactic acid bacteria, using farinograph, extensograph, amylograph, and large scale-dough mixer. According to farinograph, the addition of the flour-ferments did not influence the water-absorption rate of doughs, regardless of the kinds of flour-ferments, however, it increased development time and decreased stability of doughs. According to extensograph, both dough resistance and resistance-to-extensibility ratio increased with the addition of flour-ferments. Especially the dough containing the flour-ferments prepared with seed mash, S. cerervisiae, and L. brevis showed the highest resistance-to-extensibility ratio. According to amylograph, although the doughs containing the flour-ferments did not show the differences in gelatinization temperature and temperature at maximum viscosity with the control which does not contain the flour-ferments, they showed lower maximum viscosity than the control. They also showed lower development value and faster development time.

• Resources Recycling
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• 제4권4호
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• pp.16-21
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• 1995

When waste t~re/~vastmz otor oil is pyrolyzed. most of them hecome gaseous produds. and thc remaining onc, whascwelght is ahout in% oi the waste Ore, is pyrolyced residue mnstly composcd oi ca~bnn black A rescsrcll was canicrl nut loutilize lhe pyralyred residue of waste tnelwuste lnotol 011 us retnin~cing agent of asphall concrete, bescd on iolelg~r lesearchrepurl. This shows thal the properlies ol asphall concrele ~nclud~cd~ugl ah~l~tyre, sistance to Tear. temperature-v~scusilysusceptil,ilily u e g reatly improved when lhe pellellrcd hrln aI carlmn hlack usmg petroleum o ~als a hinder Iar ihe pellels isused with asphalt. The surface of the pyralyred resirh~ei s covned by ocl film and thla lnakes good comllatibllity with asphallIn order lo ulilk pyrolyzed residue as a reinforcing agenl oi lhe itsphalt concrete, various tests such as Marshnll tcsi, wheeltracking, and revelhng test has been carried out a1 KLER, Ko~ea I-lighway Coo~poration, and TCMO. Tcst lcsults satirry KSslandard, show "npmvements an the dynam~cs tab~l~lzym, d incrcase reslslance to wear at cold telnpelatule Invrsligadon wascarlied oul to sludg the possibility of soil pallul~on when pyrolyzed residue is used as a tzmioicing agenl. E~pcrimentalresulls show the rcsidue contained in thc asphall docs not cause cnv~ranma~lparlo blems.e cnv~ranma~lparlo blems.

• Plant Biotechnology Reports
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• 제3권3호
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• pp.243-250
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• 2009

In the present study, a simple one medium formulation protocol for callus culture, somatic embryogenesis and in vitro production of ${\beta}-carboline$ alkaloids and diosgenin in Tribulus terrestris L. was developed. Extensive callus induction and proliferation was obtained in leaf explant on Murashige and Skoog (MS) medium supplemented with $5.0{\mu}M$ 6 benzyl adenine (BA) and $2.5{\mu}M$ ${\alpha}-naphthaleneacetic$ acid (NAA). The embryogenic callus was maintained on subculture to fresh parental medium at 4-week intervals over a period of 28 months. The frequency of embryo formation was at a maximum ($18.1{\pm}0.9$ per g of callus) on MS medium containing $5.0{\mu}M$ BA and $2.5{\mu}M$ NAA together with $75mg\;1^{-1}$ casein hydrolysate. Globular embryo developed into torpedo stage embryo under the influence of starvation. The accumulation of ${\beta}-carboline$ alkaloids (harmaline and harmine) and steroidal saponin (diosgenin) in non-embryogenic and embryogenic callus culture derived from leaf explant was compared with root, leaf, stem, and fruit of the mother plant. The embryogenic callus accumulated equivalent amounts of harmaline ($66.4{\pm}0.5{\mu}g/g$ dry weight), harmine ($82.7{\pm}0.6{\mu}g/g$ dry weight), and diosgenin ($170.7{\pm}1.0{\mu}g/g$ dry weight) to that of the fruit of T. terrestris. The embryogenic callus culture of this species might offer a potential source for production of important pharmaceuticals.

• Bulletin of the Korean Chemical Society
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• 제15권5호
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• pp.379-386
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• 1994

Reactions of 1',2-bis(diphenylphosphino)-l-(N,N-dimethylaminomethyl)ferrocene (FcNPP) with $M(CO)_6$ (M=Cr, Mo, W) in the presence of TMNO (Trimethylamine oxide) in a stoichiometric ratio of 1 : 1.5 : 3.5 produced a series of Gp 6 metal carbonyl derivatives with a variety of coordination modes: M(CO)$_4({\eta}^2$-FcNPP-P,P) (M=Cr, Mo, W), $M(CO)_5({\eta}^1-FcNPP-P) (M=Mo, W)\;,\; M_2(CO)_9({\eta}^1\;,\;{\eta}^2-FcNPP-P,P,N) (M=Cr, Mo)\;,\;M_2(CO)_{10}({\eta}^1\;,\;{\eta}^1-FcNPP-P,P) (M=Cr, Mo, W)\;, and\;W(CO)_4({\eta}^2-FcNPP(O)-P,N)$. All these complexes were characterized by microanalytical and spectroscopic techniques. In one case, the structure of W(CO)$_4({\eta}^2$-FcNPP(O)-P,N) was determined by X-ray crystallography. Crystals are monocinic, space group P$2_{1/C}$, with a=10.147(2), b=19.902(3), c=19.821(4) ${\AA},\;{\beta}=96.88(2)^{\circ},\;V=3974(l){\AA}^3$, Z=4, and $D_{calc}=1.64 g cm^{-3}$. The geometry around the central tungsten metal is a distorted octahedron, with the nitrogen and phosphorus atoms being cis to each other. Some of these complexes exhibited catalytic activities in the allylic oxidation and epoxidation of cholesterly acetate. Other oxidation products were also formed with the different chemical yields and product distribution depending upon the ligand and the central metal.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제2권3호
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• pp.153-165
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• 2021

The objective of this study was to provide basic data for the conservation of wetland ecosystems in the Civilian Control Zone and the management of Yongyangbo wetlands in South Korea. Yongyangbo wetlands have been designated as protected areas. A field survey was conducted across five sessions between April 2019 and August of 2019. A total of 248 taxa were identified during the survey, including 72 families, 163 genera, 230 species, 4 subspecies, and 14 varieties. Their life-forms were Th (therophytes) - R₅ (non-clonal form) - D₄ (clitochores) - e (erect form), with a disturbance index of 33.8%. Three taxa of rare plants were detected: Silene capitata Kom. and Polygonatum stenophyllum Maxim. known to be endangered species, and Aristolochia contorta Bunge, a least-concern species. S. capitata is a legally protected species designated as a Class II endangered species in South Korea. A total of 26 taxa of naturalized plants were observed, with a naturalization index of 10.5%. There was one endemic plant taxon (Salix koriyanagi Kimura ex Goerz). In terms of floristic target species, there was one taxon in class V, one taxon in Class IV, three taxa in Class III, five taxa in Class II, and seven taxa in Class I. Three invasive alien species (Ambrosia trifida L., Ambrosia artemisiifolia L., and Humulus japonicus Siebold & Zucc) were observed. For continuous conservation of Yongyangbo Wetlands, it is necessary to remove invasive alien plants and block the inflow of non-point pollutants.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 한국표면공학회 2000년도 춘계학술발표회 초록집
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• pp.1-1
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• 2000

The results of the modification of metal materials treated by high temperature pulst:d plasma fluxes (HTlPPF) with a specific power of incident flux changing in the $(3...100)10^5{]\;}W/cm^2$ range and a pulse duration lying from 15 to $50{\;}\mu\textrm{s}$ have been presented. The results of HTPPF action were studied on the stainless steels of 18Cr-l0Ni, 16Cr- 15Ni, 13Cr-2Mo types; on the structural carbon steels of (13...35)Cr, St. 3, St. 20, St. 45 types; on the tool steels of U8, 65G, ShHI5 types, and others; on nickel and high nickel alloy of 20Cr-45Ni type; on zirconium- and vanadium-base alloys and other materials. The microstructure and properties (mechanical, tribological, erosion, and other properties) of modified materials and surface alloying of metals exposed to HTPPF action have been investigated. It was found that the modification of materials by HTPPF resulted in a simultaneous increase of several properties of the treated articles: microhardness of the surface and layers of 40...60 $\mu\textrm{m}$ in depth, tribological characteristics (friction coefficient, wear resistance), mechanical properties ({\sigma_y}, {\;}{\sigma_{0.2}}.{\;}{\sigma_r}) on retention of the initial plasticity ($\delta$), corrosion resistance, radistanation erosion under ion irradiation, and others. The determining factor of the changes observed is the structural-phase modification of the near-surface layers, in particular, the formation of the fine cellular structure in the near-surface layers at a depth of $20{\;}{\mu\textrm{m}}$ with dimension of cells changing in the range from 0.1 to $1., 5{\;}\mu\textrm{m}$, depending on the kind of material, its preliminary treatment, and the parameters of plasma fluxes. The remits obtained have shown the possibility of purposeful surface alloying of metals exposed to HTPPF action over a depth up to 20...45 $\mu\textrm{m}$ and the concentration of alloying element (Ni, Cr, V) up to 20 wt.%. Possible industrial brunches for using the treatment have been also considered, as well as some results on modifying the serial industrial articles by HTPPF.

• Safety and Health at Work
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• 제15권2호
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• pp.181-186
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• 2024

Background: This study aimed to analyze the trend of occupational noise-induced hearing loss (ONIHL) in Brazilian workers at a metallurgical plant with a hearing conservation program (HCP), which has been addressed in a previous study. Methods: All 152 workers in this time series (20032018) participated in the HCP and used personal protective equipment. All annual audiometry records in the company's software were collected from the electronic database. The trend of ONIHL was analyzed with the joinpoint regression model. The hearing thresholds of ONIHL cases at the end of the series were compared with those found in a national reference study. Results: The binaural mean hearing thresholds at 3, 4, and 6 kHz at the end of the series were higher for ages ≥50 years, exposures ≥85 dB (A), time since admission >20 years, and maintenance workers. Significance was found only in the group divided by age. There was an increasing time trend of ONIHL, though with a low percentage variation for the period (AAPC = 3.5%; p = 0.01). Hearing thresholds in this study differed from the reference one. Conclusion: Despite the unmet expectation of a stationary trend in the study period, the time pace of ONIHL evolution did not follow what was expected for a population exposed to noise. These findings signal to the scientific community and public authorities that good ONIHL control is possible when HCP is well implemented.

• BMB Reports
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• 제35권3호
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• pp.313-319
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• 2002

N-Acetyl-$\beta$-D-hexosaminidase ($\beta$-HexNAc'ase) (EC 3.2.1.52) was purified from rice seeds (Oryza sative L. var. Dongjin) using ammonium sulfate (80%) precipitation, Sephadex G-150, CM-Sephadex, and DEAE-Sephadex chromatography, sequentially. The activities were separated into 7 fractions($F_1-F_7$) by CM-Sephadex chromatography. Among them, F6 was further purified to homogeneity with a 13.0% yield and 123.3 purification-fold. The molecular mass was estimated to be about 52 kDa on SDS-PAGE and 37.4 kDa on Sephacryl S-300 gel filtration. The enzyme catalyzed the hydrolysis of both p-nitrophenyl-N-acetyl-$\beta$-D-hexosaminide (pNP-GlcNAc) and p-nitrophenyl-N-acetyl-$\beta$-D-hexosaminide (pNP-GalNAc) as substrates, which are typical properties of $\beta$-HexNAc'ase. The ratio of the pNP-GlcNAc'ase activity to the pNP-GalNAc'ase activity was 4.0. However, it could not hydrolyze chitin, chitosan, pNP-$\beta$-glucopyranoside, or pNP-$\beta$-glucopyranoside. The enzyme showed $K_m$, $V_{max}$ and $K_{cat}$ for pNP-GlcNAc of 1.65 mM, $79.49\;mM\;min^{-1}$, and $4.79{\times}10^6\;min^{-1}$, respectively. The comparison of kinetic values for pNP-GlcNAc and pNP-GalNAc revealed that the two enzyme activities are associated with a single binding site. The purified enzyme exhibited optimum pH and temperature for pNP-GlcNAc of 5.0 and $50^{\circ}C$, respectively. The enzyme activity for pNP-GlcNAc was stable at pH 5.0-5.5 and $20-40^{\circ}C$. The enzyme activity was completely inhibited at a concentration of 0.1 mM $HgCl_$ and $AgNO_3$, suggesting that the intact thiol group is essential for activity. Chloramine T completely inhibited the activity, indicating the possible involvement of methionines in the mechanism of the enzyme.

• Tuberculosis and Respiratory Diseases
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• 제44권1호
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• pp.154-161
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• 1997

Background : Although the long term adverse effects of cigarette smoking on health are well known, the acute possible detrimental effects of smoking on pulmonary or cardiovascular function, especially when these systems are stressed by the metabolic demands of exercise, have not been well studied The purpose of this study is to determine the acute action of cigarette smoking on cardiopulmonary function under stress. Method : Twenty -one healthy smoking subjects were studied. Before exrecise testing, history taking, physical examination and baseline studies, including CBC, chest PA, PFT and EKG, were done. The subjects performed an incremental bicycle exercise test to exhaustion on two occasions, one without smoking and the other after smoking 5 cigarettes/h for 2 hours. All indices of P.F.T. and bicycle ergometry were compared between before and after smoking. Results : 1. $VO_2$max and $O_2$ pulse showed significant decrease in smoking day. 2. Although there were no significant differences, anaerobic threshold showed a tendency of decrease and HRmax showed that of increase in smoking day. 3. P.F.T. and respiratory indices showed no significant change io smoking day. Conclusion : Cigarette smoking has immediate adverse effect, especially on the cardiovascular system rather than the respiratory system. These results would be due to the effect of elevated HbCO and/or impaired blood flow in response to the exercise stimulus.

• Korean Journal of Food Science and Technology
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• 제48권2호
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• pp.128-132
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• 2016

In this study, polyethylene glycol (PEG) was used to improve DNA amplification efficiency during whole genome amplification (WGA). Amplification efficiency was determined by adding PEG with different molecular weights to the WGA reaction. The greatest increase in amplification efficiency was obtained with PEG 4,000 used at 1.5% concentration. Foodborne pathogenic DNA was amplified by WGA and quantitatively analyzed by real-time polymerase chain reaction. DNA of Salmonella serotype Typhimurium, Listeria monocytogenes, and Vibrio parahaemolyticus was amplified 7,777.01, 9,981.22, and 1,239.03 fold, respectively, by WGA. On adding PEG in the WGA reaction (i.e., enhanced WGA [eWGA]), 18-40-fold more DNA amplification was achieved. Thus, these analyses showed that foodborne pathogens, which are usually present at very low concentration in foods, can be detected by real-time PCR and WGA.