• Korean journal of applied entomology
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• v.60 no.3
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• pp.287-304
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• 2021

Since 1995, researches on natural enemies have been conducted extensively in Korea. Research papers on natural enemies published in the Korean Journal of Applied Entomology from 1990 to 2020 were 130, which is 8.4% of all published papers during the same period. In 1990s, most research papers study the searching and biological characteristics of natural enemies, whereas the proportion of research papers related to the field application using the developed natural enemies has been increasing since 2010s. A total of 37 excellent natural enemies have been developed including 24 indigenous and 13 introduced natural enemies. In addition, 28 kinds of booklets and/or manuals were developed for field application of natural enemies. Although successes in research and development have been achieved since that period, more researches on search for and/or introduction of excellent natural enemy suitable for the Korean cultivation environment, mass production technology that can reduce cost, and quality control program in producing and distributing natural enemy remain to be pursued in the future. Furthermore, there is a need to develop the technology that can be used in compatible way with natural enemies and other crop protection agents including synthetic insecticides.

• Korean Journal of Ecology and Environment
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• v.54 no.3
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• pp.156-169
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• 2021

Traditional morphological identification difficulties, such as phenotypic plasticity, misidentification of cryptic species, and larval stage species, can be compensated for by using DNA analysis techniques, such as DNA barcoding, in surveying zooplankton populations, including species identification. Recently, the rapid development of DNA sequencing techniques has allowed DNA-based community analysis not only for zooplankton assemblages in various aquatic ecosystems but also for the gut contents of zooplankton that are limited by conventional methods such as visual and microscopic identification. Therefore, the application of DNA sequencing can help understand biological interactions through the analysis of zooplankton food sources. The present paper introduces the major DNA-based approaches in zooplankton research topics, including taxonomic approaches by DNA barcoding, community-level approaches by metabarcoding, and gut content analyses, summarizes the analysis methods, and finally suggests the methodological topics that need to be considered for future applications.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.488-495
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• 2009

In recent years, an increasing amount of research has been conducted on the yield loss of soybean crop caused by Riptortus clavatus, a serious pest of legumes. The objective of this study were to examine crop damage caused by various population densities of R. clavatus and determine the association of unique growth and seed characteristics with crop damage rate in conventional soybean fields. Major growth responses to R. clavatus were examined. The cultivars that were not as seriously damaged by R. clavatus were Pungsannamulkong, Sobaegknamulkong, Duyoukong, and Sinpaldal 2, but Myeongjunamulkong, Mallikong, and Hwangkeumkong were significantly (P<0.05) damaged. The rate of seed damage caused by R. clavatus was 8.2% in a group of brown colored pubescence, while the rate was 13.0% in a group of the gray colored. Crop damage by R. clavatus clearly more reduced in cultivars with dark hilum colors including dark brown, brown, and grayish brown than those with yellow hilum colors. Concerning pod colors, crop damage was less significant in cultivars with dark brown pod color than with the light brown. Cultivars with short pod length (4.0-4.5 cm) at full seed (R6) stage showed lower seed damage rates by R. clavatus than those with long pod length (>5.6 cm). Therefore, characteristics of hilum, pod, pubescence colors, and pod length were significantly related and linked to the cultivar resistance to R. clavatus.

• Korean Journal of Heritage: History & Science
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• v.48 no.4
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• pp.62-73
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• 2015

The Tae-Jo Geonwolleung is the tomb of the first king Tae-Jo of the Joseon Dynasty in the complex of the Royal Tombs of the Joseon Dynasty which is listed in World Heritage, and it contains various types of stone properties. The material of the stone properties consist of a single type of medium-grained biotite granite, however, each properties have different intensity and types in deterioration phenomena according to their locations and purposes. The major deterioration types of the stones are analyzed as physical decomposition and biodeterioration. The exfoliation, breaking-out and granular decomposition are widespread types of the deterioration throughout the entire burial mound stone properties and surrounding stone properties. On the other hands, the colonization of mosses and plants, and contamination by foreign materials are found more frequent in the burial mound stone properties as these stones are in contact with the soil of the tomb mound and moisture in the soil helped biodeterioration. It is suggested that anti-biology treatment and physical reinforcement are applied to the deteriorated stones to prevent further damage on the stone components of the tomb.

• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.402-407
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• 2019

In this study, we investigated the habitat characteristics of a reservoir in Gyeongju City, Gyeongbuk, in which a large group of Mauremys reevesii (endangered species Class II and natural monument No. 453 in Korea) was discovered. We examined the biotic and abiotic factors that directly and indirectly threaten the survival of M. reevesii within the habitat. The reservoir where M. reevesii was discovered was built for agriculture and surrounded by submerged trees, dam, forests, reeds, and farmland (paddy field). All of the M. reevesii were found only in the submerged trees on the north side of the reservoir. We found 28 M. reevesii (8 juveniles) and 21 M. reevesii (16 juveniles) from field surveys on May 10th and August 9th, 2018, respectively. A number of red-eared sliders (Trachemys scripta elegans) and American bullfrogs (Rana catesbeiana), which threaten the survival of M. reevesii, were also found in and around the reservoir. Moreover, there were signs of excavation of cultural asset, chemical fertilizer, and household garbage, all of which are considered to be major threats to the survival of M. reevesii, all over the reservoir. Newborn turtles in this year were not observed. However, we estimated that natural breeding had sufficiently occurred since we observed many young turtles in the reservoir. Furthermore, the presence of young T. s. elegans individuals can be a persistent problem for M. reevesii as they are competing species. In conclusion, in-situ conservation method should be considered for protecting the endangered turtle and their habitat.

• Korean Journal of Heritage: History & Science
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• v.37
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• pp.309-326
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• 2004

There are some methods such as fatty acid analysis and microscope analysis of parasite egg and pollen and genetic analysis of ancient bacteria from ancient soil. The fatty acid analysis can examine whether some materials is human feces or animals. This is important thing to reconstruct ancient toilet culture pattern. The methods using TLC and GC-MS as organic chemistry is able to confirm ancient diet life style and nutritive conditions. The microscope analysis of ancient soil is able to confirm ancient parasite egg and pollen. It is possible to analogize ancient human diseases from this analysis. Also, genetic analysis is able to confirm genetic diversity and variation pattern of ancient organisms in archeological soil. Most of all, it is convinced of carrying through genetic preservation of exterminated ancient organisms. If archeological soils should be analysed through the natural scientific methods such as organic chemistry, soil science, microbiology, molecular biology, and genetics, this is helpful for us to understand and interpretation past historic event. And it is expected to perform an major role for understanding origin of ancient human and life style.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.4
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• pp.592-598
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• 2019

Objective: Autophagy is a bulk degradation system for intracellular proteins which contributes to skeletal muscle homeostasis, according to previous studies in humans and rodents. However, there is a lack of information on the physiological role of autophagy in the skeletal muscle of meat animals. This study was planned as a pilot study to investigate changes in expression of two major autophagy-related genes, microtubule-associated protein 1 light chain $3{\beta}$ (MAP1LC3B) and autophagy related 7 (ATG7) in fattening beef cattle, and to compare them with skeletal muscle growth. Methods: Six castrated Japanese Black cattle (initial body weight: $503{\pm}20kg$) were enrolled in this study and fattened for 7 months. Three skeletal muscles, M. longissimus, M. gluteus medius, and M. semimembranosus, were collected by needle biopsy three times during the observation period, and mRNA levels of MAP1LC3B and ATG7 were determined by quantitative reverse-transcription polymerase chain reaction. The expression levels of genes associated with the ubiquitin-proteasome system, another proteolytic mechanism, were also analyzed for comparison with autophagy-related genes. In addition, ultrasonic scanning was repeatedly performed to measure M. longissimus area as an index of muscle growth. Results: Our results showed that both MAP1LC3B and ATG7 expression increased over the observation period in all three skeletal muscles. Interestingly, the increase in expression of these two genes in M. longissimus was highly correlated with ultrasonic M. longissimus area and body weight. On the other hand, the expression of genes associated with the ubiquitin-proteasome system was unchanged during the same period. Conclusion: These findings suggest that autophagy plays an important role in the growth of skeletal muscle of fattening beef cattle and imply that autophagic activity affects meat productivity.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.553-560
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• 2021

Theanine, the major amino acid and a sweet umami component of green tea, has anti-stress effects in humans. From green tea, theanine was extracted at 80℃ for 2 h using a low temperature, high pressure extractor, and caffeine was removed using an HP-20 column with 80% ethanol. Theanine extracts were applied to produce functional jelly using three kinds of gelling agents (I, II, and III) or various concentrations of theanine extracts (10-50%). Theanine jelly was characterized with respect to its physical properties, product stability, and physiological function. Gelling agent III (tamarind gum, xanthan gum, and locust bean gum=2:3:5, w/w/w) and S3 (35% theanine extracts) jelly exhibited the optimum textural properties with lower hardness and high springiness. Among theanine jellies, S3 exhibited optimum product stability, high 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging, and acetylcholinesterase inhibitory activity. These results indicate that the anine extracts could be used as a neuroprotective source in the food industry.

• Journal of Animal Reproduction and Biotechnology
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• v.36 no.1
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• pp.9-16
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• 2021

Under the stressed condition, a complex feedback mechanism for stress is activated to maintain homeostasis of the body and secretes several stress hormones. But these stress hormones impair synthesis and secretion of the reproductive hormones, followed by suppression of ovarian function. Cytochrome P450 1A2 (CYP1A2) plays a major role in metabolizing exogenous substances and endogenous hormones, and its expression is recently identified at not only the liver but also several organs with respect to the pancreas, lung and ovary. Although the expression of CYP1A2 can be also affected by several factors, understanding for the changed pattern of the ovarian CYP1A2 expression upon stress induction is still limited. Therefore, CYP1A2 expression in the ovaries from immobilization stress-induced rats were assessed in the present study. The stress-induced rats in the present study exhibited the physiological changes in terms of increased stress hormone level and decreased body weight gains. Under immunohistological observation, the ovarian CYP1A2 expression in both control and the stressed ovary was localized in the antral to pre-ovulatory follicles. However, its expression level was significantly (p < 0.01) higher in the stress-induced group than control group. In addition, stress-induced group presented more abundant CYP1A2-positive follicles (%) than control group. Since expression of the ovarian CYP1A2 was highly related with follicle atresia, increased expression of CYP1A2 in the stressed ovary might be associated with changes of the ovarian follicular dynamics due to stress induction. We hope that these findings have important implications in the fields of the reproductive biology.

• Journal of Life Science
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• v.31 no.2
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• pp.237-247
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• 2021

Immune responses in the central nervous system (CNS) function as the host's defense system against pathogens and usually help with repair and regeneration. However, chronic and exaggerated neuroinflammation is detrimental and may create neuronal damage in many cases. The NOD-, LRR-, and pyrin domain―containing 3 (NLRP3) inflammasome, a kind of NOD-like receptor, is a cytosolic multiprotein complex that consists of sensors (NLRP3), adaptors (apoptosis-associated speck like protein containing a caspase recruitment domain, ASC) and effectors (caspase 1). It can detect a broad range of microbial pathogens along with foreign and host-derived danger signals, resulting in the assembly and activation of the NLRP3 inflammasome. Upon activation, NLRP3 inflammasome leads to caspase 1-dependent secretion of the pro-inflammatory cytokines IL-1β and IL-18, as well as to gasdermin D-mediated pyroptotic cell death. NLRP3 inflammasome is highly expressed in CNS-resident cell types, including microglia and astrocytes, and growing evidence suggests that NLRP3 inflammasome is a crucial player in the pathophysiology of several neuroinflammatory and psychiatric diseases, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, stroke, traumatic brain injury, amyotrophic lateral sclerosis, and major depressive disorder. Thus, this review describes the molecular mechanisms of NLRP3 inflammasome activation and its crucial roles in the pathogenesis of neurological disorders.