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A rapid and high-quality single-nucleotide polymorphisms (SNPs)-based method was developed to improve detection and reduce salmonellosis burden. In this study, whole-genome sequence (WGS) was used to investigate SNPs, the most common genetic marker for identifying bacteria. SNP-sites encompassing 15 sets of primers (666-863 bp) were selected and used to amplify the target

The objectives of this study were to select morphological keys for the identification of individual endangered long-tailed gorals through analysis of photographic data and to use these morphological keys to determine the number and population composition of gorals living in the Osaek Region of Seoraksan National Park. Amongst 8149 photos taken using 73 cameras in the Osaek Region, 2057 photos of faces and horns were analysed. The presence and absence of horns, shape of the horns, proportion of the ring to the length of the horn and facial colour pattern were selected as morphological keys to identify individual gorals. To verify the accuracy of the morphological keys for identifying gorals, a blind test was performed on gorals residing in the sanctuary of the Yanggu Goral Restoration Center. The test revealed that the population and age of gorals were discerned correctly by the morphological keys, but there was a 12.5% error in discriminating between sexes in gorals aged over 10 years. Fifty-six gorals were identified from 2057 pictures, based on the morphological keys and methods developed in this study. The population of 56 individuals consisted of 43 individuals aged over 2 years (subadult or adult) and 13 offspring aged less than 2 years, with a ratio of 3.3:1. Of the total 56 individuals, 45% were adults aged 10 years or older, 18% were adults aged 3–10 years, 7% were subadults aged 2–3 years, 23% were offspring aged less than 2 years and 7% were individuals aged 2 years or older, whose age and sex could not be confirmed. The sex ratio of males to females was 1.17:1, with a corrected sex ratio of 1:1 considering the 12.5% error rate for gorals aged over 10 years, amongst the 39 gorals aged over 2 years.

The long-tailed goral (also called the Amur goral) Naemorhedus caudatus (subfamily Caprinae), a vulnerable and protected species designated by IUCN and CITES, has sharply been declining in the population size and is now becoming critically endangered in South Korea. This species has been conserved as a natural monument by the Korean Cultural Heritage Administration since 1968. In this study, using 78 fecal DNA samples with a non-invasive genetic approach, we assessed the genetic integrity and individual identification-based population size for the goral population from Seoraksan National Park representing the largest wild population in Korea. Using the successfully isolated 38 fecal DNA, phylogeographic and population genetic analyses were performed with mitochondrial DNA control region (CR) sequences and nine microsatellite loci. We found seven CR haplotypes, of which five were unique to the Seoraksan population, considering previously determined haplotypes in Korean populations. The Seoraksan population showed higher haplotype diversity (0.777 ± 0.062) and mean number of alleles (4.67 ± 1.563) relative to southern populations in Korea reported from previous studies, with no signal of a population bottleneck. Microsatellite-based individual identification estimate based on probability of identity (PID) indicated a population size of ≥30 in this population. Altogether, we suggest that for future management efforts of this species in the Seoraksan National Park, conserving its genetic integrity as an ‘endemic’ lineage, and curbing a decrease in its number through mitigating habitat destruction might be key to secure the population for the long term.

Ambiguous, heterogeneous, endospore-forming Bacillus species, notably Bacillus cereus, often produce fatal toxins that threaten human health. We identified Bacillus from wild animal fecal samples (n = 80), including the Korean water deer (n = 25) and striped field mouse (n = 55). Using traditional culture-based methods, 25 animal fecal samples (31.25%; 25/80) were found to be positive for Bacillus species, whereas using molecular techniques, 19 samples (23.75%; 19/80) were found to be positive for the same. In addition, we designed a Bacillus species-specific 16S ribosomal RNA (rRNA) gene marker and utilized it to identify 19 samples by means of PCR amplification and sequencing, using at least one colony from the 19 Bacillus positive samples. The recovered sequences were matched to sequences of three Bacillus species (B. cereus, B. amyloliquefaciens, and B. megaterium) from the GenBank database. Moreover, the phylogenetic tree generated in this study established specific clades for the Bacillus group. In addition, to differentiate between B. cereus, B. anthracis, and B. thuringiensis, we designed a single nucleotide polymorphism (SNP)-based primer by identifying SNPs in the alignment of 16S rRNA gene sequences of B. cereus group strains. The SNPs were used to design primer sets for discrimination between highly similar species from the B. cereus group. The study could be used in surveillance of agricultural fresh-produce-associated Bacillus outbreaks, for accurate identification of each Bacillus species, and in the development of control measures.

Ambiguous, heterogeneous, endospore-forming

Single-nucleotide polymorphisms (SNPs) are one of the most common forms of genetic variation and as such are powerful tools for the identification of bacterial strains, their genetic diversity, phylogenetic analysis, and outbreak surveillance. In this study, we used 15 sets of SNP-containing primers to amplify and sequence the target

Background Understanding the habitat characteristics of the endangered Siberian flying squirrel Pteromys volans is the first step in conserving and managing the forests it requires for nesting, gliding, and feeding. Therefore, in the present study, we characterized the habitats of P. volans using GIS analysis of 411 forest sites in South Korea where fecal droppings were found. Results Fecal signs of P. volans were found in various regions in South Korea, including the Baekdudaegan Mountains. GIS analysis with six environmental layers (vegetation type, wood-age class, diameter at breast height [DBH], crown density, elevation, and distance from stream) revealed that fecal signs of P. volans were more frequently found in broad-leaved deciduous forests (42%) located 200–399 m above sea level (43.1%) and 0–199 m from the nearest stream (53%), with 5th class wood-age (35.3%), middle size class DBH (51.1%), and high crown density (71%). Conclusions The present study provides information on the biotic and abiotic characteristics of P. volans habitats. In South Korea, the fecal droppings of P. volans were found predominantly old deciduous broadleaf forests. Further studies are needed to reveal whether the more frequent occurrence of P. volans dropping in broadleaf forests may be due to a particular preference of this species for the forests or to a simple reflection of the area of the broadleaf forests occupying a much larger area than other forest types in Korea.

We determined and annotated the complete mitogenome of the house bat Pipistrellus abramus (Chiroptera: Vespertilionidae) from Korea. The complete mitogenome is a circular molecule of 17,236 bp in length, including 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and 2 non-coding regions (L-strand replication origin and control region). The mitogenome is AT-biased, with a nucleotide composition of 33.7% A, 29.9% T, 23.2% C, and 13.2% G. The phylogenetic analysis revealed that the house bat P. abramus from Korea is well grouped with that from Japan and placed within the genus Pipistrellus clade, which has the noctule bat Nyctalus as sister clade.

Wild animals, such as rodents seem to be competent reservoir of bacteria-borne zoonotic diseases which disseminate in human. We investigated the presence of E. coli, Shiga toxin-producing E. coli (STEC), and Salmonella in the feces of six category wild rodent species (Apodemus agrarius, A. peninsulae, A. sylvaticus, Micromys minutus, Myodes regulus, and R. norvegicus) captured from different agricultural regions in South Korea. Among them, A. agrarius, which account for 65% of total (N = 52) individuals, are most widely distributed and abundant in various agroecosystems in South Korea. The bacterial identification was performed by cultural and molecular methods. In cultural method, the fecal cultures from 26 individuals formed colonies on E. coli-selective EMB agar media. Of them, the fecal cultures from 18 individuals also produced colonies on the Shiga toxin-producing E. coli-selective CT-SMAC agar media as well as the EMB agar media. In molecular method, polymerase chain reaction (PCR) was carried out to detect two virulence genes (stx1 and stx2) of isolated E. coli. The amplified dataset of stx1 and stx2 genes of E. coli were sequenced. In this manuscript, E. coli and STEC were detected but there were no Salmonella species. The wild rodents’ data would provide important information on reservoirs of those pathogenic bacteria.

In the present study, behavioral states for habitat selection are examined using a discrete-time Markov chain (DTMC) combined with a network model with wildlife movement data. Four male boars (Sus scrofa Linnaeus) at the Bukhansan National Park in South Korea were continuously tracked with an interval of approximately 2 h to 313 days from June 2018 to May 2019. The time-series movement positions were matched with covariates of environmental factors (leaf types and water) in field conditions. Stationary probabilities were used to quantify the habitat selection preference of wild boars, including maximum probability (0.714) with the “broadleaf without water habitat” where in-degree centrality was at its maximum (0.54), but out-degree centrality was low and even (0.17) for all states. Betweenness was the maximum for the “needleleaf without water habitat”, suggesting its role as a bridging habitat between other habitats. Out-closeness scores presented the highest values in the “broadleaf without water habitat” (0.26). Similarly, the first hitting time to the habitat was shortest at the “broadleaf without water habitat” (3.64–5.16 h) and slightly longer than one day in other examined habitats, including “broadleaf with water,” “needleleaf without water,” and “no-leaf without water”. The network model using the Markov chain provided information on both local movement behavior and general resource-use patterns of wild boars in field conditions.

Almost all examined cockroaches harbor an obligate intracellular endosymbiont, Blattabacterium cuenoti. On the basis of genome content, Blattabacterium has been inferred to recycle nitrogen wastes and provide amino acids and cofactors for its hosts. Most Blattabacterium strains sequenced to date harbor a genome of approximately 630 kbp, with the exception of the termite Mastotermes darwiniensis ( approximately 590 kbp) and Cryptocercus punctulatus ( approximately 614 kbp), a representative of the sister group of termites. Such genome reduction may have led to the ultimate loss of Blattabacterium in all termites other than Mastotermes. In this study, we sequenced 11 new Blattabacterium genomes from three species of Cryptocercus in order to shed light on the genomic evolution of Blattabacterium in termites and Cryptocercus. All genomes of Cryptocercus-derived Blattabacterium genomes were reduced ( approximately 614 kbp), except for that associated with Cryptocercus kyebangensis, which comprised 637 kbp. Phylogenetic analysis of these genomes and their content indicates that Blattabacterium experienced parallel genome reduction in Mastotermes and Cryptocercus, possibly due to similar selective forces. We found evidence of ongoing genome reduction in Blattabacterium from three lineages of the C. punctulatus species complex, which independently lost one cysteine biosynthetic gene. We also sequenced the genome of the Blattabacterium associated with Salganea taiwanensis, a subsocial xylophagous cockroach that does not vertically transmit gut symbionts via proctodeal trophallaxis. This genome was 632 kbp, typical of that of nonsubsocial cockroaches. Overall, our results show that genome reduction occurred on multiple occasions in Blattabacterium, and is still ongoing, possibly because of new associations with gut symbionts in some lineages.

Single-nucleotide polymorphisms (SNPs) are one of the most common forms of genetic variation and as such are powerful tools for the identification of bacterial strains, their genetic diversity, phylogenetic analysis, and outbreak surveillance. In this study, we used 15 sets of SNP-containing primers to amplify and sequence the target Escherichia coli. Based on the combination of the 15-sequence primer sets, each SNP site encompassing forward and reverse primer sequences (620–919 bp) were aligned and an SNP-based marker was designed. Each SNP marker exists in at least two SNP sites at the 3′ end of each primer; one natural and the other artificially created by transition or transversion mutation. Thus, 12 sets of SNP primers (225–488 bp) were developed for validation by amplifying the target E. coli. Finally, a temperature gradient triplex PCR kit was designed to detect target E. coli strains. The selected primers were amplified in three genes (ileS, thrB, and polB), with fragment sizes of 401, 337, and 232 bp for E. coli O157:H7, E. coli, and E. coli O145:H28, respectively. This allele-specific SNP-based triplex primer assay provides serotype-specific detection of E. coli strains in one reaction tube. The developed marker would be used to diagnose, investigate, and control food-borne E. coli outbreaks.

최근 국내 철도는 고속화와 통과톤수(MGT)의 증가에 의해 보다 높은 수준의 궤도 안정성과 내구성을 확보하기 위하여 엄밀 하면서도 새로운 궤도노반 분류기준의 재정립이 요구되고 있다. 현재 해외 철도 선진국은 대부분 자국 내 철도 궤도 노반전용 의 흙재료 분류기준을 제정하여 사용하고 있다. 일본의 경우 철도총합기술연구소(RTRI)에서 2007년에 간행한 ‘철도구조물등 설 계표준 동해설[1]’을 통하여 성토구간 흙쌓기용 재료분류기준을 새롭게 제시한 바 있다. 독일 또한 자체의 독자적 흙분류기준을 제정하여 사용하고 있다[2]. 이는 독일이 위치한 고유의 지형학적 토질분류 특성을 반영하도록 한 것이며, 매우 엄밀한 노반전 Abstract The soils used as trackbed in Korea are selected using USCS utilizing basic soil properties such as Grain Size Distribution(GSD), % passing of #200 sieve (P200), % passing of #4 sieve (P4), Coefficient of uniformity (Cu), and Coefficient of curvature (Cc). Degree of compaction of the soils adapted in the code by KR should be evaluated by maximum dry density (γd-max) and deformation modulus Ev2. The most important influencing factor that is critical to stability and deformation of the compacted soils used as trackbed is stiffness. Thus, it is necessary to construct a correlation between the modulus and the basic soil properties of trackbed soil in order to redefine a new soil classification system adaptable only to railway construction. To construct the relationship, basic soil test data is collected as a database, including GSD, maximum dry unit weight (γd-max), OMC, P200, P4, Cu, Cc, etc.; deformation modulus Ev2 and Evd are obtained independently by performing a Repeated Plated Bearing Test (RPBT) and Light Weight Deflectometer Test (LWDT) for ten different railway construction sites. A linear regression analysis is performed using SPSS to obtain the relationship between the basic soil properties and the deformation modulus Ev2 and Ev. Based on the constructed relationship and the various obtained mechanical test data, a new soil classification system will be proposed later as a guideline for the design and construction of trackbed foundation in Korea.

Lithium-ion batteries are generally used in mobile devices, but the voltage range of the battery varies from 2.7 to 4.2V. To provide a mid-3V-range output from the battery, a converter capable of step-up/down-conversion is necessary. For this purpose, non-inverting buck-boost topologies with multimode control [1-3] have been widely used. However, they have limited efficiency slightly higher than 90%, which comes from the fact that a main current path always encompasses two switches. To increase the efficiency in the buck mode where the converter operates for most of the usage time, a flying capacitor buck-boost (FCBB) was proposed in [4]. Despite its high power efficiency, it requires large-size LDMOS to endure a large voltage range up to 8V at switching node, resulting in cost inefficiency. Since all these topologies have a common controller that covers both buck and boost modes of operation, compensator design is challenging. Moreover, a non-minimum-phase system of boost operation makes it hard to achieve a fast loop response. In this paper, we propose a step-up/down DC-DC converter based on buck operation only over the whole input voltage range, which greatly simplifies the controller design and consequently gives fast response. Furthermore, it achieves high efficiency because of the reduced effective resistance on the main current path.

A micro-bolometer focal plane array (MBFPA) detector is one of the best candidates for thermal imaging cameras due to its excellent uncooled imaging performance with low manufacturing cost [1-4]. In Fig. 10.8.1, remote infra-red signals from thermal objects are maximized and absorbed at the MEMS micro-bolometer pixels having a λ/4 cavity structure, and they are then converted into resistance of a thermistor layer in each cell. Then, a CMOS analog front-end (AFE) reads out the cell resistance value in current-mode by applying a voltage bias to the micro-bolometer pixel. In the readout process, the skimming cell that does not respond to the infra-red signal is used to remove the offset components by generating an opposite-phase current, which in turn alleviates the system required resolution. Nevertheless, there is still very significant fixed-pattern noise (FPN) resulting from process, voltage, and temperature (PVT) variations, and this severely limits the responsivity/dynamic range trade-off. Addressing the problem, both bias voltages (V FID & V GSK ) applied to sensing and skimming cells, respectively, should be precisely adjusted so as to avoid any saturation while maintaining sufficient responsivity, and their noise levels must be low enough considering the noise amplification in the signal chain.

We investigated habitat characteristics of the yellow-throated marten Martes flavigula (Carnivora : Mustelidae) using geographic information system (GIS). GPS coordinates of the target mammal traces and seven habitat factors were used for the GIS analysis. The Odaesan National Park (ONP) is selected as a study area for GIS analysis of the habitat characteristics. According to the GIS analysis of whole area of ONP, main forest type was broadleaf trees which occupy 72% of forests. Trees of 4th to 6th age-calss account for 93% of the ONP forests. The mean elevation and slope of ONP was 901 m and 22.1 o , respectively. According to the GIS analysis of M. flavigula habitats in ONP, most M. flavigula traces were found in borad-leaf forests and coniferous forests which are main forest types of ONP. In addition, the yellow-throated marten recorded a relatively high appearance rate of 7% in unstocked forests, which account for much less than 1% of the area of ONP. Most of the marten traces were found in forests with trees of 4th to 6th age-classes. The traces were found in the forest types in higher elevation (1,080.3 m) and lower slope (15.0 o ) on average, compared with those of ONP. Appearance rate of the marten traces was 96% in range less than 600 m from the water. The traces were frequently found in areas far distantly beyond 1,400 m range from human residental areas and cultivated areas.

We sequenced and characterized the complete mitogenome (KX964606) of the Amur hedgehog Erinaceus amurensis to provide more data for comparative mitogenomics of the genus Erinaceus (Erinaceidae). The mitogenome of E. amurensis is a circular molecule 16,941 bp long, consisting of a control region and a conserved set of 37 genes containing 13 protein-coding genes, 22 tRNA genes, and two rRNA genes (12S rRNA and 16S rRNA). The mitogenome of E. amurensis is AT-biased, with a nucleotide composition of 33.9% A, 21.1% C, 32.6% T, and 12.4% G. The mitogenomes of E. amurensis and the closely related hedgehog species E. europaeus, excluding the control region (66.7%), share over 90% sequence similarity. According to the inter-generic relationship based on six mitogenomes described from five genera of Erinaceidae, the subfamilies Erinaceinae and Galericinae are strongly supported as monophyletic groups, with each genus well placed within its own subfamily. Within the subfamily Erinaceinae, E. amurensis is a sister species to E. europaeus, and the relationship between Hemiechinus and Erinaceus is strongly supported. Within the subfamily Galericinae, the clade of Hylomys + Neotetracus was sister to that of Echinosorex, with clades supported by high values. Our findings will help to understand the codon usage pattern and molecular evolution of E. amurensis, and provide insight into inter-generic relationships within the family Erinaceidae. In future studies, the inclusion of mitogenomes from other genera would greatly enhance our understanding of higher phylogeny within the Erinaceidae.

본 연구는 멸종위기종인 한국산 산양(n=3)의 생태 및 행동학적 특징을 밝히기 위하여 2010년 5월부터 2011년 9월까지 설악산국립공원에서 이루어졌다. 구조된 산양은 GPS Collar 발신기를 부착하여 구조된 원서식지에 재 방사 하였으며, 연구기간 동안 수집된 4,752개의 위치 좌표를 이용하여 연간 행동권, 계절별 행동권, 월별 이용 고도를 분석하였다. 연구결과, 설악산 산양의 연간 행동권은 MCP 95% 0.88km2, MCP 50% 0.27km2, FK 95% 0.43km2, FK 50% 0.09km2로 계절별 행동권은 MCP 95%에서 봄 0.47km2, 여름 0.45km2, 가을 0.63km2, 겨울 0.50km2로, 가을 행동권이 넓은 것으로 나타났다. 또한 FK 95% 분석을 통해서도 봄 0.23km2, 여름 0.19km2, 가을 0.33km2, 겨울 0.22km2로 가을철 행동권이 가장 큰 것으로 나타났다. 암·수 연간행동권은 MCP 95% 수준에서 암컷 1.03km2, 수컷은 0.58km2로 분석되었다. 월별 이용 고도는 6, 7, 8월이 가장 높았으며 12, 1, 2월에 가장 낮은 고도를 이용했다. 본 연구는 산양의 서식지 관리 정책 및 복원과 보전을 위한 객관적 자료 확보 및 국내에서 수행 중이거나 계획 단계에 있는 야생동물의 성공적인 복원에 기여하고자 수행되었다.

The mitogenome of the Siberian flying squirrel Pteromys volans is a circular molecule of 16,514 bp, consisting of a control region and a conserved set of 37 genes containing 13 protein-coding genes (PCGs), 22 tRNA genes, and 2 rRNA genes (12S rRNA and 16S rRNA). The mitogenome of the Korean P. volans is AT-biased, with a nucleotide composition of 32.2% A, 30.4% T, 12.5% G, and 24.8% C. The phylogenetic analysis revealed that P. volans is well placed within the tribe Pteromyini (Sciuridae: Sciurinae), which forms a sister clade to the flying squirrels of the genus Petaurista.

Wild mouse feces can disseminate zoonotic microorganisms throughout a farm, which is a great threat to human health and can lead to economic loss through contaminated agricultural produce. To assess the microbial communities, especially fecal coliform bacteria, we used two methods. First, we isolated bacterial colonies onto the common media LB (lactose broth) agar, TSA (tryptic soy agar), and MRS (de Man, Rogosa, and Sharpe) agar, and then randomly select colonies from each plate and stocked them to the mother plate for genomic DNA isolation. Second, we analyzed bacterial colonies using the 16S rRNA gene molecular diagnostic method. Based on bacterial cultures and bacterial 16S rRNA gene markers, we detected four different bacterial species (Bacillus amyloliquefaciens, Escherichia coli, Staphylococcus xylosus, and Serratia liquefaciens) from fecal coliforms of the striped field mouse Apodemus agrarius and A. peninsulae in agricultural areas in South Korea. These results could help us to better understand the pathogen reservoirs of mice and initiate some preventive measures to mitigate the microbial risks associated with mouse fecal matter in agricultural production areas.

Several different shut-down procedures were carried out to reduce the degradation of membrane electrode assembly (MEA) in a proton exchange membrane fuel cell (PEMFC). The effects of close/open state of outlets of a single cell and application of a dummy load during the shut-down on the degradation of the MEA were investigated. Also, we elucidated the relationship between the thickness of the electrolyte membrane and the degradation of the MEA for different shut-down procedures. When a thin electrolyte membrane was used, the closer of outlets mitigated the degradation during on/off operation. For the thicker electrolyte membrane, the dummy load which eliminates residual hydrogen and oxygen in the electrodes should be applied to lower the degradation.

Degradation of polymer electrolyte membrane fuel cell (PEMFC) that is facilitated by on/off cycles is one of the most important issues for commercialization of fuel cell vehicles. When a PEMFC stack is shut down, residual hydrogen and induce high voltage equivalent to open circuit voltage to the cathode side that might cause sintering of Pt catalyst and facilitate formation of hydrogen peroxide at the anode side that might decompose membrane. In this study, degradation of PEMFC exposed to repetitive on/off cycles was investigated by measuring i-V characteristics, ac impedance, cyclic voltammograms, gas leak, cross-sectional SEM images, and TEM images. To prevent degradation of PEMFC caused by the residual gases, hydrogen was removed from anode gas channel by gas-purging and by using a dummy resistance, that were found to be a very effective method.

To determine the composition of myosin heavy chain (MHC) isoforms in rat extraocular muscles (EOMs) during postnatal development.The MHC composition of rat EOMs at postnatal day 0 (P0), postnatal day 14 (P14), and adults was evaluated at mRNA levels by competitive polymerase chain reaction and MHC composition of each six EOM in adult rats.EOMs at P0 revealed predominant expression of neonatal MHC (75.5%) with a lesser percentage of embryonic MHC (12.8%) and 2A MHC (11.5%). 2X MHC was expressed at low levels and other MHC isoforms were not detected. At P14, EOMs expressed mostly 2X MHC (42.4%) and 2A MHC (27.4%). Expression levels of neonatal MHC (14.1%) and embryonic MHC (4.9%) decreased. 2B MHC (8.2%), EOM MHC (1.9%), and beta-cardiac MHC (1.1%) were detected at low levels. In the adult rats, EOMs contained over 80% of three fast MHC isoforms, such as 2X MHC (29.9%), 2A MHC (29.3%), and 2B MHC (24.5%). Each of six adult EOM showed slightly different expression levels of MHC composition.A strong correlation exists between the composition of fast MHC isoforms and muscle development. MHC isoform followed a neonatal MHC-2X MHC-2B MHC isoform switching pattern after birth. Postnatal development of EOMs had a slightly different expression pattern for MHC isoforms and may have different regulatory roles related to their functional requirement.