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The extended distribution and potential introduction of exotic ticks and associated tick-borne pathogens along the northern and southern routes of migratory birds pose zoonotic tick-borne disease r...

Travelling from across its breeding range in northern Eurasia, Yellow-breasted Buntings (Emberiza aureola) stopover in China before migrating to their wintering areas in South-East Asia and the Indian subcontinent. This species is now considered critically endangered because its global population has declined dramatically; moreover, it is overexploited by illegal trapping at its stopover sites during the moult. Currently, two subspecies of the Yellow-breasted Bunting are recognized: aureola and ornata. However, the moult strategies of these subspecies at their stopover sites remain unknown. In the present study, we analysed the moult and plumage patterns of E. a. ornata in Korea (n = 262) between 2005 and 2018 as part of a long-term bird ringing project at a key migrant stopover site. We observed significant sexual dimorphism in the morphological characteristics of both adults and immatures: the males had longer wings, tails, and tarsi, and weighed more than the females. Moult patterns were distinct in relation to age. Adults underwent a complete post-breeding moult, entirely replacing their body and flight feathers before the onset of autumn migration over a breeding range. Remarkably, 93.4% of first-winter birds underwent an eccentric primary moult, having moulted the 3–4 outermost primaries (P6–P9 or P7–P9) before arriving at the stopover site. Males achieve full adult breeding plumage in their second summer. More than three types of median wing coverts were identified in the first-winter males, with various plumage colours and patterns. To the best of our knowledge, this is the first report on the moulting and plumage patterns in the subspecies ornata as it passes through an East Asian migratory flyway stopover site in Korea. Our results will contribute to an understanding of the migration behaviour and subspecies populations that are at risk in their specific environments. This is essential for ecological monitoring to facilitate the conservation of this critically endangered species.

The extended distribution and potential introduction of exotic ticks and associated tick-borne pathogens along the northern and southern routes of migratory birds pose zoonotic tick-borne disease risks to wild and domestic animals and incidentally to humans. A knowledge of bird migratory patterns, species of attached ticks, and associated pathogens during their migrations to and from their feeding and nesting grounds is central to understanding associated tick-borne disease risks. Tick-borne disease surveillance was conducted from 2010 to 2011 and 2016 at Hong-do (do = island), Heuksan-do, and Nan-do, major stopovers for migratory birds in Republic of Korea (ROK), as part of the Migratory Birds Research Center bird-banding program for studying bird migration patterns in the ROK. A total of 877 ticks belonging to three genera and nine species were collected

In a follow-up to the investigations of soft ticks identified from seabird nest soil and litter collected from coastal islands of the Republic of Korea (ROK), Ornithodoros sawaii and Ornithodoros capensis were assessed for the presence and identification of rickettsiae. Ticks collected from samples of 50–100 g of nest litter and soil from seabird nests were identified individually by morphological techniques, and species confirmed by sequencing of the mt-rrs gene. Subsequently, tick DNA preparations were screened for the presence of rickettsiae using a genus-specific nested PCR (nPCR) assay targeting the 17 kDa antigen gene. The amplicons from the 17 kDa assay and two additional nPCR assays targeting the gltA and ompB gene fragments were sequenced and used to identify the rickettsiae. A total of 134 soft ticks belonging to two species, O. sawaii Kitaoka & Suzuki 1973 (n = 125) and O. capensis Neumann 1901 (n = 9), were collected. Rickettsia lusitaniae DNA was detected and identified among O. sawaii ticks (n = 11, 8.8%) collected from nest litter and soil of the Japanese murrelet (Synthliboramphus wumizusume Temminck 1836) at Gugul Island along the western coastal area of the ROK. This study confirmed for the first time the presence of R. lusitaniae associated with O. sawaii collected from migratory seabird nests in the ROK.

To compare the retinal layer thickness values obtained using two swept-source optical coherence tomography (OCT) wide modes. This study included fifty-four healthy eyes. Three-dimensional (3D) wide and 12 radial wide OCT scans were performed in each eye on the same day. Full retinal, retinal nerve fiber layer (RNFL), and ganglion cell–inner plexiform layer (GC–IPL) thicknesses with fully automated segmentation obtained in 3D wide mode, and with semi-automated correction and fully automated segmentation obtained in 12 radial wide scan. The intraclass correlation coefficients for full retinal thickness measurements obtained by the two protocols with fully automated segmentation were from 0.958 to 0.996, 0.754–0.918 for GC–IPL thickness measurements, and 0.013–0.727 for RNFL thickness measurements, in the nine ETDRS subfields. The full retinal thickness measurements determined using both fully automated segmentation algorithms were reliable and clinically acceptable. However, segmentation errors are shown when using the 12 radial wide scanning protocol with fully automated segmentation for measurement of RNFL and GC–IPL thickness.

Sex determination is a key component in many ecological and evolutionary studies, and morphological measurements, based on reversed sexual size dimorphism (RSD), are the most widely used means of sexing raptors. We studied morphometrics and sexual dimorphism of the poorly documented Chinese Goshawk (Accipiter soloensis) in the Republic of Korea, where we measured 54 birds and developed discriminant functions to allow sexing. The species showed apparent, but small, RSD in all of eight measured parameters, with the dimorphic index ranging from 1.39 for tarsus to 16.09 for body mass. A stepwise discriminant procedure, followed by discriminant function analysis (DFA), indicated that tail, bill, and head lengths were all reliable parameters for sex determination of goshawks with an accuracy of 100% among 30 individuals. Head length is often unavailable from museum specimens; however, a discriminant function using tail and bill lengths classified the sex of 44 goshawks with an accuracy of 95.5%. Our mo...

Migratory birds were captured, examined, banded and then released in accordance with a bird banding protocol of the Bird Research Center, National Park Research Institute, Korea National Park Service, from January-December 2010–2011 on Hong and Heuksan Islands, Jeollanam (Jeonnam) Province, in the Republic of Korea (ROK). Concurrently, ticks were collected from captured birds as part of a tick-borne disease surveillance program. A total of 381 ticks belonging to three genera and eight species – Ixodes turdus (297 ticks), Ixodes nipponensis (16), Haemaphysalis flava (46), Haemaphysalis longicornis (9), Haemaphysalis formosensis (5), Haemaphysalis ornithophila (6), Haemaphysalis concinna (1), and Amblyomma testudinarium (1)—were collected from 32 bird species belonging to 3 families. This is the first host report of A. testudinarium (1 nymph) collected from White’s Thrush, Zoothera aurea (Aves: Passeriformes: Turdidae), in the ROK. Most ticks were collected from birds during the months of April (44.1%) and November (54.2%).

The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migratory Birds Research Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program on Gugul and Sogugul Islands, two small, remote, uninhabited islands in southwestern Jeollanam Province, Republic of Korea (ROK) from 2015–2016. Ticks were collected from nest soil/litter of the Ancient Murrelet, Synthliboramphus antiquus, Japanese Murrelet, Synthliboramphus wumizusume, and Swinhoe’s Storm Petrel, Hydrobates monorhis, using Tullgren funnels. A total of 100 Ornithodoros sawaii (25 females, 56 males, 17 nymphs, and 2 larvae) were collected from 2/33 (6.1%) Ancient Murrelet, 3/11 (27.3%) Japanese Murrelet, and 23/94 (24.5%) Swinhoe’s Storm Petrel nest sites. In addition, 3 larvae were collected from Swinhoe’s Storm Petrel nestlings. Ticks were identified morphologically and species determination was confirmed using polymerase chain reaction techniques. This is the first record of O. sawaii collected from nest soil/litter of the Japanese Murrelet during this bird’s nesting season in the ROK.

The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migratory Birds Research Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program during 2014–2015 on two small, remote, uninhabited islands, Hong (Gull) Island, southern Gyeongnam Province, and Nan Island, western Chungnam Province, Republic of Korea (ROK). Argasid ticks were collected from Black-tailed Gull (Larus crassirostris) nestlings that had recently died and associated nest soil/litter, and all tick life history stages were identified morphologically. Because morphological keys are unreliable for the identification of adult and nymphal argasid ticks, identifications were confirmed by genotyping using polymerase chain reaction techniques. A total of 29 Ornithodoros capensis larvae and 2 Ornithodoros sawaii larvae were collected from 4 of 7 (57.1%) Black-tailed Gull nestlings that had recently died. An additional five O. capensis (2 males, 1 nymph, and 2 larvae) were collected from nest soil/litter. Only O. sawaii larvae (2/41, 4.9%) were collected from dead Black-tailed Gull nestlings on Nan Island. This is the first report of O. capensis from these seabird breeding islands.

The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migratory Birds Research Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program on Chilbal Island during 2016. Chilbal Island is a small, remote, uninhabited government-protected island in southwestern Jeollanam Province, Republic of Korea (ROK). Ticks were collected from nest soil and litter of the Ancient Murrelet, Synthliboramphus antiquus, using Tullgren funnels. A total of 4 Ixodes ticks (3 male Ixodes uriae and 1 female Ixodes signatus) were collected. The principal hosts of I. uriae are pelagic birds that have a largely circumpolar distribution. Ixodes signatus parasitizes other migratory birds in coastal areas of western North America and eastern Asia. This is the first report of I. uriae from the ROK.

The 65th Medical Brigade and Public Health Command District-Korea, in collaboration with the Migratory Birds Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program on Chilbal Island, a small, remote, uninhabited island in southwestern Jeollanam Province, Republic of Korea (ROK), during 2014–2015. Ticks were collected by dragging vegetation and from nest soil and litter of the Ancient Murrelet, Synthliboramphus antiquus, and Swinhoe’s Storm Petrel, Hydrobates monorhis, using Tullgren funnels. A total of 115 ticks belonging to three genera and three species were collected. Ornithodoros sawaii (98.3%, 113 ticks) was the most frequently collected tick species, followed by Ixodes signatus (0.9%, 1 nymph) collected from nest soil and litter, and Haemaphysalis flava (0.9%, 1 male) collected by tick drag.

The 65 th Medical Brigade and Public Health Command Region-Pacific (Korea), in collaboration with the Migratory Birds Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program on Chilbal Island, a small, remote, uninhabited island in southwestern Jeollanam Province, Republic of Korea (ROK), on 1 and 31 May and 15 September 2014. Ticks were collected from nesting soil and litter of the Ancient Murrelet, Synthliboramphus antiquus , and Swinhoe’s Storm Petrel, Hydrobates monorhis , using Tullgren funnels. A total of 12 Ornithodoros sawaii (2 females, 4 males, and 6 nymphs) were collected from 3/36 (8.3%) S. antiquus and 6/20 (30.0%) H. monorhis nest sites. Ticks were identified morphologically and species determination was confirmed using polymerase chain reaction techniques. This is the first report of the genus O rnithodoros and species O. sawaii from the ROK.

【Coal-tar pitch, a feedstock which can be heat-treated to create graphite, is composed of very complex molecules. Coal-tar pitch is a precursor of many useful carbon materials (e.g., graphite, carbon fibers, electrodes and matrices of carbon/carbon composites). Modified coal-tar pitch (MCTP) was prepared using two different heat-treatment methods and their properties were characterized and compared. One was prepared using heat treatment in nitrogen gas; the other was prepared under a pressure of 350 mmHg in air. The MCTPs were investigated to determine several properties, including softening point, C/H ratio, coke yield, formation of anisotropic mesophase and viscosity. The MCTPs were subject to considerable changes in chemical composition due to condensation and polymerization in the used-as-received coal-tar pitch after heat-treatment under different conditions. The MCTPs showed considerable increases in softening point, C/H ratio, and coke yield, compared to those of as-received coal-tar pitch. The MCTP formed by heat-treatment in nitrogen showed isotropic phases below $350^{\circ}C$ for 1 h of soaking time. However, MCTP heat-treated under high pressure (350 mmHg) showed isotropic phases below $300^{\circ}C$ , and showed anisotropic phases above $350^{\circ}C$ , for 1 h of soaking time. The viscosity of the MCTPs increased with increase in their softening points.】

Coal tar is the primary feedstock of premium graphitizable carbon precursor. Coal tars are residues formed as by-products of thermal treatments of coal. Coal tar pitches were prepared through two different heat treatment schedules and theirproperties were characterized. One was prepared with argon and oxidation treatment with oxygen; the other was prepared withoxygen treatment at low temperature and then argon treatment at high temperature; both used coal tar to prepare coal tar pitches.To modulate the properties, different heat treatment temperatures (300~400 o C) were used for the coal tar pitches. The preparedcoal tar pitches were investigated to determine several properties, such as softening point, C/H ratio, coke yield, and aromaticityindex. The coal tar pitches were subject to considerable changes in chemical composition that arose due to polymerization afterheat treatment. Coal tar pitch showed considerable increases in softening point, C/H ratio, coke yields, and aromaticity indexcompared to those characteristics for coal tar. The contents of gamma resin, which consists of low molecular weight compoundsin the pitches and is insoluble in toluene, showed that the degree of polymerization in the pitches was proportional to C/H ratio.Using an oxidizing atmosphere like air to prepare the pitches from coal tar was an effective way to increase the aromaticityindex at relatively low temperature.Key wordscoal tar, coal tar pitch, softening point, C/H ratio, coke yield.