• Parasites, Hosts and Diseases
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• 제55권5호
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• pp.555-559
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• 2017

Chigger mites are parasites of rodents and other vertebrates, invertebrates, and other arthropods, and are the only vectors of scrub typhus, in addition to other zoonoses. Therefore, investigating their distribution, diversity, and seasonal abundance is important for public health. Rodent surveillance was conducted at 6 districts in Shandong Province, northern China ($114-112^{\circ}E$, $34-38^{\circ}N$), from January to December 2011. Overall, 225/286 (78.7%) rodents captured were infested with chigger mites. A total of 451 chigger mites were identified as belonging to 5 most commonly collected species and 3 genera in 1 family. Leptotrombidium scutellare and Leptotrombidium intermedia were the most commonly collected chigger mites. L. scutellare (66.2%, 36.7%, and 49.0%) was the most frequently collected chigger mite from Apodemus agrarius, Rattus norvegicus, and Microtus fortis, respectively, whereas L. intermedia (61.5% and 63.2%) was the most frequently collected chigger mite from Cricetulus triton and Mus musculus, respectively. This study demonstrated a relatively high prevalence of chigger mites that varied seasonally in Shandong Province, China.

• Asian-Australasian Journal of Animal Sciences
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• 제21권11호
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• pp.1673-1679
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• 2008

In order to study the biological function of gapdh gene in yak, and prove whether the gapdh gene was a useful intra-reference gene that can be given an important role in molecular biology research of yak, the cDNA sequence encoding glyceraldehyde-3-phosphate dehydrogenase from yak was cloned by the RT-PCR method using gene specific PCR primers. The sequence results indicated that the cloned cDNA fragment (1,008 bp) contained a 1,002 bp open reading frame, encoding 333 amino acids (AAs) with a molecular mass of 35.753 kDa. The deduced amino acids sequence showed a high level of sequence identity to Bos Taurus (99.70%), Xenopus laevis (94.29%), Homo sapiens (97.01%), Mus musculus (97.90%) and Sus scrofa (98.20%). The expression of yak's gapdh gene in heart, spleen, kidney and brain tissues was also detected; the results showed that the gapdh gene was expressed in all these tissues. Further analysis of yak GAPDH amino acid sequence implied that it contained a complete glyceraldehyde-3-phosphate dehydrogenase active site (ASCTTNCL) which ranged from 148 to 155 amino acid residues. It also contained two conserved domains, a NAD binding domain in its N-terminal and a complete catalytic domain of sugar transport in its C-terminal. The phylogenetic analysis showed that yak and Bos taurus were the closest species. The prediction of secondary structures indicated that GAPDH of yak had a similar secondary structure to other isolated GAPDH. The results of this study suggested that the gapdh gene of yak was similar to other species and could be used as the intra-reference to analyze the expression of other genes in yak.

• Parasites, Hosts and Diseases
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• 제47권3호
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• pp.311-314
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• 2009

A total of 1,498 small mammals (rodents and insectivores), including Apodemus agrarius (n= 1,366), Crocidura lasiura (54), Mus musculus (32), Micronytus fortis (28), Eothenomys regulus (9), Micronys minutes (6), and Cricetulus triton (3), were live-trapped in Gyeonggi-do (Province) (Paju-si, Pocheon-gun, and Yeoncheon-gun) near the demilitarized zone (DMZ) from December 2004 to September 2005. A. agrarius was found to be infected with 3 species of echinostomes (Echinostoma hortense, Echinostoma cinetorchis, and Euparyphium murinum), while C. lasiura was infected with 1 species (Echinochasmus japonicas) of echinostome. Other mammals were free from echinostome infections. Total 16 E. hortense were detected in 7 (0.5%) mice, 9 E. cinetorchis from 5 (0.4%), and 3 E. murinum from 2 (0.1%) out of 1.366 A. agrarius examined. E. japonicus was found only in 1 (1.9%; total 3 specimens) C. lasiura. These results demonstrate that A. agrarius and C. lasiura, inhabiting near the DMZ of Gyeonggi-do serve as the natural definitive hosts for several species of echinostomes, although their infection rates are low. This is the first record of natural infections of A. agrarius with E. cinetorchis and C. lasiura with E. japonicus in the Republic of Korea.

• Parasites, Hosts and Diseases
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• 제45권2호
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• pp.153-156
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• 2007

The small intestines of 6 species of rodents and 1 species of insectivore were examined seasonally for Plagiorchis muris infection in 3 different localities in northern Gyeonggi-do (Province), near the demilitarized zone (DMZ). A total of 1,496 animals, including 1,366 Apodemus agrarius, 54 Crocidura iasiura (insectivore), 32 Mus musculus, 28 Micronytus fortis, 9 Eothenomys regulus, 6 Micronys minutus, and 3 Cricetulus triton, were live-trapped at Yeoncheon-gun (n = 351), Paju-shi (804) and Pocheon-gun (343) at 3-mo intervals from December 2004 to September 2005. A total of 1,647 P. muris were collected from 72 (5.3%) A. agrarius. The infection rate was the high-est in Pocheon-gun (8.2%), followed by Yeoncheon-gun (5.0%) and Paju-shi (4.2%). A higher infection rate was observed in A. agrarius captured during September (19.4%) than those captured during December (3.0%), June (2.6%), or April (0%). However, the worm burden was the highest in June (av. 32.1/animal), followed by September (24.7), December (4.0), and April (0). None of the other animal species were found infected with P. muris. The results reveal that A. agrarius is a natural definitive host for P. muris, and infection rates and worm burdens vary seasonally and geographically.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.53-60
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• 2002

Motion of lung tumors from respiration has been reported in the literature to be as large as of 1-2 cm. This motion requires an additional margin between the Clinical Target Volume (CTV) and the Planning Target Volume (PTV). While such a margin is necessary, it may not be sufficient to ensure proper delivery of Intensity Modulated Radiotherapy (IMRT) to the CTV during the simultaneous movement of the DMLC. Gated treatment has been proposed to improve normal tissues sparing as well as to ensure accurate dose coverage of the tumor volume. The following questions have not been addressed in the literature: a) what is the dose error to a target volume without gated IMRT treatment\ulcorner b) what is an acceptable gating window for such treatment. In this study, we address these questions by proposing a novel technique for calculating the 3D dose error that would result if a lung IMRT plan were delivered without gating. The method is also generalized for gated treatment with an arbitrary triggering window. IMRT plans for three patients with lung tumor were studied. The treatment plans were generated with HELIOS for delivery with 6 MV on a CL2100 Varian linear accelerator with a 26 pair MLC. A CTV to PTV margin of 1 cm was used. An IMRT planning system searches for an optimized fluence map ${\Phi}$ (x,y) for each port, which is then converted into a dynamic MLC file (DMLC). The DMLC file contains information about MLC subfield shapes and the fractional Monitor Units (MUs) to be delivered for each subfield. With a lung tumor, a CTV that executes a quasi periodic motion z(t) does not receive ${\Phi}$ (x,y), but rather an Effective Incident Fluence EIF(x,y). We numerically evaluate the EIF(x,y) from a given DMLC file by a coordinate transformation to the Target's Eye View (TEV). In the TEV coordinate system, the CTV itself is stationary, and the MLC is seen to execute a motion -z(t) that is superimposed on the DMLC motion. The resulting EIF(x,y)is inputted back into the dose calculation engine to estimate the 3D dose to a moving CTV. In this study, we model respiratory motion as a sinusoidal function with an amplitude of 10 mm in the superior-inferior direction, a period of 5 seconds, and an initial phase of zero.

• 환경영향평가
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• 제26권2호
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• pp.160-170
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• 2017

본 연구는 2006년부터 2012년까지 수행된 제3차 전국자연환경조사 포유류 데이터(70,562개)를 활용하여 국내에서 서식하는 포유류의 서식지 유형을 클러스터링하고 서식지 유형에 나타나는 종의 특징을 파악하고자 하였다. 제3차 전국자연환경조사의 야장에 기록된 서식지 유형 중에서 15개의 키워드를 뽑아 재분류하여 포유류 서식지유형을 통계 분석하였다. 서식지 유형 군집분석에서는 30회 이상 기록된 14개의 서식지 유형을 대상으로 비계층적 클러스터 분석(k 평균 클러스터 분석), 계층적 클러스터 분석, 비계량형 다차원척도법을 시행하였다. 2006년에서 2012년까지 전국에서 수집된 제3차 전국자연환경조사를 통해 확인된 포유류는 총 7목 16과 39종이었다. 서식지 유형에 대한 분류는 11개로 클러스터를 분류했을 때 단순구조지수가 가장 높았다(ssi = 0.07). 계층적 클러스터 분석으로 서식지 유형들 간의 유사성과 위계를 확인해 본 결과, 포유류에게는 주거지가 가장 차별된 서식지 유형이었고, 그 다음은 하천과 해안이 병합된 클러스터였다. 비계량형 다차원척도 분석 결과, 포유류에게 가장 차별된 서식지유형인 주거지의 경우 생쥐와 집쥐 두 종이 제한적으로 나타났으며, 해안과 하천의 경우 수달이 제한적으로 나타났다. 연구결과를 종합해보면, 포유류의 서식지 유형은 크게 산림을 주요 서식지와 이동경로로 이용하는 산림형과, 물을 주요 서식지로 이용하는 하천형, 주거지 인근에서 서식하는 주거형, 곡류나 씨앗을 주 먹이원으로 하는 저지대형 등 4가지로 구분할 수 있다.