• Journal of dental hygiene science
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• v.16 no.5
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• pp.393-399
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• 2016

The objective of this study was to realize research demands by gathering the research agenda from the Korean Dental Hygienists Association and affiliated groups through a Delphi survey. The study subjects were the heads of eight groups. The Delphi survey was conducted by e-mail after a researcher explained the objective of the study to the heads. The research agenda was classified according to the Korean dental hygiene academic classification and the National Dental Hygiene Research Agenda classification. To compare the number of research agendas according to classification among the groups, we conducted a chi-squared test by using IBM SPSS 20.0. In total, 316 agendas were submitted. According to the Korean dental hygiene academic classification, there was a significant difference among the groups, and the agendas associated with clinical dental hygiene (36.7%) were the best. According to the National Dental Hygiene Research Agenda classification, there was no significant difference and the agendas associated with health promotion and disease prevention (27.8%) were the best. In conclusion, the Korean Dental Hygienists Association and affiliated groups demanded similar research agendas, corresponding to the purpose of each establishment. However, the groups did not seem to show unique characteristics according to the purpose of each establishment. In other words, the groups should corroborate such characteristics and suggest a corresponding agenda to establish specific areas of research in dental hygiene. Also, dental hygiene researchers should mark the academic classification of the studies they want to submit.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.501-507
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• 2010

The aim of the current study was to analyze the diversity of the major surface protein (Msp) gene in Theileria buffeli, which is known as the major antigenic protein recognized by the immune system of the host. In addition, we characterized the diversification of the Msp gene and its relationship to with the pathogenicity of Theileria. Complete blood counts (CBC) and Theileria 18S rRNA PCR sequence analysis were performed for 177 Korean indigenous cattle (KIC) in Jeju Island. A total of 28 KIC (16 anemic and 12 non-anemic KIC) were then randomly selected based on 18s rRNA PCR positive samples for sequence analysis of the Theileria Msp gene, which was performed twice for each specimen. The resulting 56 Msp gene sequences were classified into five antigenicity types (type I to V), according to the variable region (517-571 bp), which exhibited high similarity (${\geq}$ 98.9%) to several available GenBank sequences (Theileria spp. from China-EU584237; T. sergenti from China-DQ078264; Theileria spp. from Thailand-AB081329; Theileria spp. from Japan-AB218442; T. sergenti from Japan-AB016280). The 56 Msp sequences consisted of 22, 15, 9, 8, and 2 cases of type I to type V Msp genes, respectively. The most prevalent type in both anemic and non-anemic KIC was type I (37.5% in anemic and 41.7% in non-anemic). Among the remaining types, type II was the most prevalent (37.5%) in anemic KIC, while type IV was the most prevalent (25%) in non-anemic KIC. The results of our study help confirm the diversity of Msp gene types and demonstrate that the gene type distribution of Msp genes varies among Theileria-infected KIC in Jeju Island.

• Journal of the Korean Wood Science and Technology
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• v.37 no.3
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• pp.255-264
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• 2009

To evaluate the effects of chemical pretreatments of lignocellulosic biomass on enzymatic hydrolysis process, Populus euramericana was pretreated for 1 hr with 1% sulfuric acid ($H_2SO_4$) at $150^{\circ}C$ and 1% sodium hydroxide (NaOH) at $160^{\circ}C$, respectively. Before the enzymatic hydrolysis, each pretreated sample was subjected to drying process and thus finally divided into four subgroups; dried or non-dried acid pretreated samples and dried or non-dried alkali pretreated samples and chemical and physical properties of them were analyzed. Biomass degradation by acid pretreatment was determined to 6% higher compared to alkali pretreatment. By the action of acid ca. 24.5% of biomass was dissolved into solution, while alkali degraded ca. 18.6% of biomass. However, reverse results were observed in delignification rates, in which alkali pretreatment released 2% more lignin fragment from biomass to the solution than acid pretreatment. Unexpectedly, samples after both pretreatments were determined to somewhat higher crystallinity than untreated samples. This result may be explained by selective disrupture of amorphous region in cellulose during pretreatments, thus the cellulose crystallinity seems to be accumulated in the pretreated samples. SEM images revealed that pretreated samples showed relative rough and partly cracked surfaces due to the decomposition of components, but the image of acid pretreated samples which were dried was similar to that of the control. In pore size distribution, dried acid pretreated samples were similar to the control, while that in alkali pretreated samples was gradually increased as pore diameter increased. The pore volume which increased by acid pretreatment rapidly decreased by drying process. Alkali pretreatment was much more effective on enzymatic digestibility than acid pretreatment. The sample after alkali pretreatment was enzymatically hydrolyzed up to 45.8%, while only 26.9% of acid pretreated sample was digested at the same condition. The high digestibility of the sample was also influenced to the yields of monomeric sugars during enzymatic hydrolysis. In addition, drying process of pretreated samples affected detrimentally not only to digestibility but also to the yields of monomeric sugars.

• Korean Journal of Medicinal Crop Science
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• v.4 no.4
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• pp.301-307
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• 1996

The experiment was conducted to clarify the effect of water stress treatment on growth character of Ligusticum chuanxiong Hort. The water stress treatment was imposed artificially on seedling, flowering and rhizome enlargement stage of the plant. The decrease ratio of leaf area compare with control decreased to 24.4% by water stress treatment at seedling stage and to 41.6% at rhizome enlargement stage. The reduction rate of chlorophyll content at the end of water stress treatment was 41.2% at the see­dling stage and no difference at the flowering stage. The chlorophyll content of water stress treatment on seedling and flowering stage was recovered to 95% at harvest time. The ratio of rootlet distribution from top soil to l0cm depth showed maximum to 90% at the seedling stage and to 20cm depth showed max­imum to 6.4% at the rhizome enlargement stage. The dry weight of rootlet was decreased to $19.3{\sim}40.3%$ by water stress treatment. Dry weight of aerial part and underground part of the plant decreased in the order of seedling, flowering, rhizome enlargement and control and the dry weight of aerial part decrease more severely than underground part.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.733-742
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• 2000

Fundamental materialistic characterization and adsorption/neutralization behavior of waste egg shell for heavy metal ion have been studied for its application to wastewater treatment. To investigate the structural change and thermal decomposition characteristics of egg shell. X-ray diffraction and FT-IR analysis were conducted for egg shell treated at $105^{\circ}C$ and $700^{\circ}C$, respectively. For the result of FT-IR analysis, the sample treated at $700^{\circ}C$ showed a reduced C-O absorption band compared with that of egg shell treated at $105^{\circ}C$, which may be due to the $CO_2$ release. Unlike to the result of FT-IR analysis, the XRD patterns of egg shell were almost similar for the cases of $105^{\circ}C$ and $700^{\circ}C$ treatment. however, characteristic diffraction pattern of CaO was observed for $850^{\circ}C$ treatment, at which $CaCO_3$ is known to be completely converted to CaO. TGA/DTA analysis showed a slow decline in weight loss up to $600^{\circ}C$ and, for $600{\sim}800^{\circ}C$ range, the weight loss became drastic by reason of $CO_2$ discharge, which was accompanied by an appearance of major endothermic peak. The ratio of practical breakthrough time to ideal one, total transfer unit, and mass transfer coefficient were observed to be increased as the adsorption was progressed in a multiple-column fixed-bed reactor using egg shell as an adsorbent, which signified the distribution effect of mass transfer for continuous adsorption reaction. The neutralization effect of egg shell for several types of acidic wastewater made of different mineral acids was not much different from each other except for the case of $H_2SO_4$, for which the neutralization reaction was thought to be retarded by the formation of gypsum.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1265-1273
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• 2005

The purpose of this study was to prepare accelerated salt-fermented anchovy sauce using a shrimp processing byproducts (head, shell and tail) as a fermenting accelerator, and to investigate its physicochemical and enzymatic properties. Four types of sauces were prepared with 0, 10, 20, and 30$\%$ (w/w) addition of shrimp byproduct and fermented at 24$\pm$2$^{\circ}C$ for 360 days. During fermentation, all four type sauces decreased moisture content (67.5$\%$68.0$\%$ to 64.0$\∼$64.8$\%$) and pH (5.52$\∼$7.10 to 5.03$\∼$6.58), but showed increase in their crude protein (7.0$\∼$8.2 to 10.8$\%$) and volatile basic nitrogen contents (40$\∼$75 to 180$\∼$200 mg/100 g of sauce). The ratio of amino nitrogen to total nitrogen contents of control (0$\%$) and sauce with 10$\%$ shrimp byproducts (10$\%$ sauce) were maximized at 270 days, whereas 20$ \% $ and 30$\%$ added sauces were at 180 days. Endoprotease and exoprotease activities of anchovy sauces added with 20$\%$ and 30$\%$ of shrimp byproducts tend to be higher than those of control (0$\%$) and 10$\%$ addition. Proteolytic activities of sauces at pH 9 were about 2 times higher than those at pH 6. Amidolytic activities for LeuPNA decreased remarkably during fermentation, and control (0$\%$) almost lost their activity at 180 days, while additional sauces were relatively stable. These suggest that alkaline pretense of anchovy and shrimp byproducts as a endoprotease mainly contributed to the fermentation of salt-fermented sauces. The protein molecular weight distribution of sauces indicated 2 groups of peaks (peak 1,>70,000 da and peak 2, 3,000$\∼$29,000 da). As the fermentation proceeded, peak 1 tended to decrease in all of sauces, but peak 2 increased rapidly from 30 to 270 days. Optimum fermentation periods of control and 10$\%$ sauces were 270 days and those of 20$\%$ and 30$\%$ sauce were 180 days. The results suggest that shrimp byproduct can be used as accelerator of salt-fermented sauce.

• Journal of Korean Society of Forest Science
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• v.80 no.1
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• pp.42-53
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• 1991

1. The forest vegetation of the Mt. Baek-Hwa situated in the northwestern Kyungsangpookdo of Korea, on $36^{\circ}16^{\prime}00^{{\prime}{\prime}}{\sim}36^{\circ}19^{\prime}20^{{\prime}{\prime}}N$ and 127 53'20"~127 56'30"E was studied by the method of Zurich-Montpellier School. In the present time, the original vegetation have almost been dominated by substitutional communities such as secondary forests of Pinus, Quercus, Zelkova, Acer or Fraxinus and Pinus rzgida plantations. Some secondary forests developing along the ravine and in northwestern part of slope are, however, maintained in natural condition, and contain some species of the original climax vegetation. They are classified as follows : I. Quercus mongolica-Fraxinus siebol diana community(Mountain forests), I-A. Acer pseudo-sieboldianum -Carex okamotoi group, I-B. Pinus densiflora group, I-B-a. Typical subgroup, I-B-b. Rhododendron schlippenbachii subgroup, II. Fraxinus rhynclzophylla-Acer mono community(Valley Forests), II-A. Acer pseudo-sieboldianum group, II-B. Zelkova serrata group, II-B-a. Typical subgroup, II-B-b. Lindera erythrocarpa subgroup, II-C. Querczrs serrata-Platycarya strobilacea group, II-C-a. Typical subgroup, II-C-b. Lindera erythrocarpa subgroup. 2. Judging from the coincidence method, the structure and distribution of the forest communities was more related to topography than altitude. 3. Considering the actual vegetation, relict species, occurrence of natural seedlings and saplings, climate, successional trends of trees and topographic or edaphic climax conditions, it seems that potential natural vegetation of the area mainly composed of Quercus mongolica, Carpinus laxiflora, Zelkova serrata, Fraxinus rhynchophylla. 4. The flora of the vascular plants collected from this area consists of 108 families, 371 genera, 613 species, 2 subspecies, 88 varieties, 6 forms and 709 taxa in total.

• Journal of Korean Society of Forest Science
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• v.88 no.3
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• pp.352-363
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• 1999

It has been rare to obtain reliable information related to the size of forest land in North Korea. Several sources of forest statistics, ranging from the first map of forest distribution in Korean Peninsula produced in 1910 to official data reported by the North Korea Government in 1997, were gathered and analyzed to define the characteristics of forest cover changes over years. In addition, Landsat satellite data obtained from 1973 to 1993 were processed for the two study areas of the provinces of Pyungyang and Heasan, where the topography and land use pattern are significantly different each other. Using three sets of multitemporal Landsat imagery, land cover ma-ps were produced by computer classification. Although forest statistics reported before 1990 are somewhat inconsistent, they mere gradually decreasing over years. The estimates of 1991 satellite data and the recent statistics reported in 1998 shows very steep decline in forest lands as compared to the ones before 1990. The abrupt decrease of forest lands after 1990 was also found on the detailed analysis of Landsat data for the two study areas of Pyungyang and Heasan. The rapid decline of forest lands may have something to do with the poor economic situation of the country and the continuing natural disasters of severe flooding and drought. Unstocked forest, which was not classified into forest land, was a very distinct and pervasive land cover type that can be easily observed on satellite imagery. Since unstocked forest land in North Korea may be a critical factor for degrading environmental quality as well as for the continuing natural disasters, further analysis is necessary to define the exact extent and the physical characteristics of the cover type.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.12
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• pp.715-732
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• 2009

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2008. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends in thermal and fluid engineering have been surveyed in the categories of general fluid flow, fluid machinery and piping, new and renewable energy, and fire. Well-developed CFD technologies were widely applied in developing facilities and their systems. New research topics include fire, fuel cell, and solar energy. Research was mainly focused on flow distribution and optimization in the fields of fluid machinery and piping. Topics related to the development of fans and compressors had been popular, but were no longer investigated widely. Research papers on micro heat exchangers using nanofluids and micro pumps were also not presented during this period. There were some studies on thermal reliability and performance in the fields of new and renewable energy. Numerical simulations of smoke ventilation and the spread of fire were the main topics in the field of fire. (2) Research works on heat transfer presented in 2008 have been reviewed in the categories of heat transfer characteristics, industrial heat exchangers, and ground heat exchangers. Research on heat transfer characteristics included thermal transport in cryogenic vessels, dish solar collectors, radiative thermal reflectors, variable conductance heat pipes, and flow condensation and evaporation of refrigerants. In the area of industrial heat exchangers, examined are research on micro-channel plate heat exchangers, liquid cooled cold plates, fin-tube heat exchangers, and frost behavior of heat exchanger fins. Measurements on ground thermal conductivity and on the thermal diffusion characteristics of ground heat exchangers were reported. (3) In the field of refrigeration, many studies were presented on simultaneous heating and cooling heat pump systems. Switching between various operation modes and optimizing the refrigerant charge were considered in this research. Studies of heat pump systems using unutilized energy sources such as sewage water and river water were reported. Evaporative cooling was studied both theoretically and experimentally as a potential alternative to the conventional methods. (4) Research papers on building facilities have been reviewed and divided into studies on heat and cold sources, air conditioning and air cleaning, ventilation, automatic control of heat sources with piping systems, and sound reduction in hydraulic turbine dynamo rooms. In particular, considered were efficient and effective uses of energy resulting in reduced environmental pollution and operating costs. (5) In the field of building environments, many studies focused on health and comfort. Ventilation. system performance was considered to be important in improving indoor air conditions. Due to high oil prices, various tests were planned to examine building energy consumption and to cut life cycle costs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.959-967
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• 2005

Lead is a ubiquitous environmental and industrial pollutant that causes a major health concerns. It is known to induce a broad range of physiological, biochemical, and behavioral dysfunctions in laboratory and humans, including hematopoietic system, kidneys, liver, and reproductive system. This study was conducted to investigate the effect of Saengshik supplementation on the lead-induced toxicity in rats. Five week old male Sprague­Dawley rats were randomly assigned to five groups for six weeks as followings: control group (CT), lead acetate treated group (PT), and lead acetate groups administered with three different dosages of Saengshik $(SI2.5-12.5\%,\;S25-25\%,\;and\;S50-50\%).$ Lead acetate (12 mg/rat) was intragastrically administered daily for 6 weeks. The results were summarized as follows; Weight gain and food efficiency ratio were significantly lower (p<0.05) in lead administered group compared with those of the control group. Also, significant lead-induced alteration in blood hemoglobin (HGB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and reticulocyte distribution width (RDW) were observed. In the liver of lead-exposed animals, there was an increase in the lipid peroxidation (MDA) and the level of glutathione (GSH), but superoxiede dismutase (SOD) activity did not change. Lead-exposed animals with $25\%\;and\;50\%$ Saengshik supplementation showed marked improvements in the values of MCH, MCV, and RDW. Also, the level of HCT was significantly increased by $50\%$ Saengshik supplementation. The levels of liver MDA in $12.5\%\;and\;50\%$ Saengshik administered groups and GSH level in $50\%$ Saengshik administered group were significantly decreased compared to the lead administered group. Also, hepatic SOD activity tended to increase in the presence of Saengshik supplementation. Furthermore, the accumulation of lead in liver and kidney was reduced by presence of Saneghshik supplementation. Liver lead concentration was significantly reduced by both $25\%\;and\;50\%$ Saengshik supplementations and kidney lead concentration was significantly reduced by the $25\%$ Saengshik supplementation. These results show that Saengshik may have a protective effect against lead intoxication but the mechanism of their effects remains unclear.