• 제목/요약/키워드: Canonical Structure

검색결과 136건 처리시간 0.026초

Echolocation Call Structure of Fourteen Bat Species in Korea

  • Fukui, Dai;Hill, David A.;Kim, Sun-Sook;Han, Sang-Hoon
    • Animal Systematics, Evolution and Diversity
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    • 제31권3호
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    • pp.160-175
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    • 2015
  • The echolocation calls of bats can provide useful information about species that are generally difficult to observe in the field. In many cases characteristics of call structure can be used to identify species and also to obtain information about aspects of the bat's ecology. We describe and compare the echolocation call structure of 14 of the 21 bat species found in Korea, for most of which the ecology and behavior are poorly understood. In total, 1,129 pulses were analyzed from 93 echolocation call sequences of 14 species. Analyzed pulses could be classified into three types according to the pulse shape: FM/CF/FM type, FM type and FM/QCF type. Pulse structures of all species were consistent with previous studies, although geographic variation may be indicated in some species. Overall classification rate provided by the canonical discriminant analysis was relatively low. Especially in the genera Myotis and Murina, there are large overlaps in spectral and temporal parameters between species. On the other hand, classification rates for the FM/QCF type species were relatively high. The results show that acoustic monitoring could be a powerful tool for assessing bat activity and distribution in Korea, at least for FM/QCF and FM/CF/FM species.

How Z-DNA/RNA binding proteins shape homeostasis, inflammation, and immunity

  • Kim, Chun
    • BMB Reports
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    • 제53권9호
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    • pp.453-457
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    • 2020
  • The right-handed double-helical structure of DNA (B-DNA), which follows the Watson-Crick model, is the canonical form of DNA existing in normal physiological settings. Even though an alternative left-handed structure of DNA (Z-DNA) was discovered in the late 1970s, Z-form nucleic acid has not received much attention from biologists, because it is extremely unstable under physiological conditions, has an ill-defined mechanism of its formation, and has obscure biological functions. The debate about the physiological relevance of Z-DNA was settled only after a class of proteins was found to potentially recognize the Z-form architecture of DNA. Interestingly, these Z-DNA binding proteins can bind not only the left-handed form of DNA but also the equivalent structure of RNA (Z-RNA). The Z-DNA/RNA binding proteins present from viruses to humans function as important regulators of biological processes. In particular, the proteins ADAR1 and ZBP1 are currently being extensively re-evaluated in the field to understand potential roles of the noncanonical Z-conformation of nucleic acids in host immune responses and human disease. Despite a growing body of evidence supporting the biological importance of Z-DNA/RNA, there remain many unanswered principal questions, such as when Z-form nucleic acids arise and how they signal to downstream pathways. Understanding Z-DNA/RNA and the sensors in different pathophysiological conditions will widen our view on the regulation of immune responses and open a new door of opportunity to develop novel types of immunomodulatory therapeutic possibilities.

슬라이딩 모드 고유치 설정에 기반을 둔 가변구조 제어 설계 (Variable Structure Control Design Based on Eigenvalues Assignment of Sliding Mode)

  • 홍연찬;이태봉
    • 한국산학기술학회논문지
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    • 제11권6호
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    • pp.2207-2213
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    • 2010
  • 본 논문에서는 FSM(finite-state machine)을 이용하여 차수 계산(degree computation)을 하지 않고 수정된 유클리드 알고리즘(modified Euclidean algorithm)을 구현할 수 있는 구조를 제안한다. 제안된 구조는 차수계산이 필요없기 때문에 RS(Reed-Solomon) 복호기의 하드웨어 복잡도를 줄일 수 있고, 고속의 복호기 설계가 가능하게 된다. 제안된 구조를 이용하는 RS(255,239) 복호기를 Verilog HDL로 구현하였고, 기존의 복호기에 비해 게이트 수를 약 13%정도 줄일 수 있다.

Numerical Experiments of Ocean Acoustic Tomography in the East Sea of Korea

  • Han, Sang-Kyu;Na, Jung-Yul;Lee, Jae-Hak
    • Journal of the korean society of oceanography
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    • 제31권2호
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    • pp.64-74
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    • 1996
  • Numerical experiments of OAT (Ocean Acoustic Tomography) are carried out in the East Sea of Korea where the canonical ocean has been perturbed by a mesoscale warm eddy and a thermal front. In order to estimate the horizontal and vertical structure of water temperature of the perturbed ocean, the experimental area is divided into 16 cells with 8 pairs of sources and receivers for a horizontal slice and the water column is divided into 8 layers for a vertical slice. The inversely estimated temperature field by using SVD (Singular Value Decomposition) method reveals the eddy and frontal structure clearly. The rms errors of the two horizontal slices are less than $0.4^{\circ}C$ and $1.7^{\circ}C$ at 400 m and 200 m depths, respectively, while the error in the vertical slice is less than $1.0^{\circ}C.$ For better estimation of temperature by OAT method, particularly for the East Sea, a range-dependent ray model should be used to solve the forward problem. At the same time, improvement in computing the refracted ray path between vertical layers is required to obtain more accurate travel time information. The results of the present experiment give rise to a possibility of application of OAT in remote sensing of the ocean thermal structure.

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CONTACT THREE CR-SUBMANIFOLDS OF A (4m + 3)-DIMENSIONAL UNIT SPHERE

  • Kim, Hyang-Sook;Kim, Young-Mi;Kwon, Jung-Hwan;Pak, Jin-Suk
    • 대한수학회지
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    • 제44권2호
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    • pp.373-391
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    • 2007
  • We study an (n+3)($n\;{\geq}\;7-dimensional$ real submanifold of a (4m+3)-unit sphere $S^{4m+3}$ with Sasakian 3-structure induced from the canonical quaternionic $K\"{a}hler$ structure of quaternionic (m+1)-number space $Q^{m+1}$, and especially determine contact three CR-submanifolds with (p-1) contact three CR-dimension under the equality conditions given in (4.1), where p = 4m - n denotes the codimension of the submanifold. Also we provide necessary conditions concerning sectional curvature in order that a compact contact three CR-submanifold of (p-1) contact three CR-dimension in $S^{4m+3}$ is the model space $S^{4n_1+3}(r_1){\times}S^{4n_2+3}(r_2)$ for some portion $(n_1,\;n_2)$ of (n-3)/4 and some $r_1,\;r_2$ with $r^{2}_{1}+r^{2}_{2}=1$.

범주형 환경변수를 고려한 부대성과평가 방법에 관한 연구 - DEA와 CCCA의 결합을 중심으로 - (Performance Evaluation of Military Corps with Categorical Environmental Variables)

  • 이경원;박명섭;임재풍
    • 한국국방경영분석학회지
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    • 제32권1호
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    • pp.51-72
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    • 2006
  • 계층구조로 이루어진 군부대에서 예하부대의 성과는 피평가부대의 개별적인 노력뿐만 아니라, 그 부대가 속해있는 지휘라인의 1차 상급지휘관의 부대지휘방향에 따라 상당한 영향을 받는 경우가 많다 평가를 담당하는 기관인 2차 상급조직에서 제시하는 평가요소에 대한 중요도가 1차 상급지휘관의 부대지휘방향과 상이하다면, 해당부대는 1차 상급지휘관의 의도를 충실히 구현하였음에도 불구하고 다른 지휘라인의 부대들보다 낮은 평가를 받을 수 있다. 본 연구는 계층적 구조하에서 성과방향의 차이를 야기하는 지휘라인별 특성을 집단외생변수로 취급하여 평가의 공정성을 기하기 위한 연구이다. 비모수적 기법인 DEA와 모수적 기법으로서 다수의 종속변수가 존재하고 모수의 제약을 반영할 수 있는 제약정준상관분석(CCCA: Constrained Canonical Correlation Analysis)의 결합모형을 이용하였으며, 이 과정에서 성과에 영향을 미치는 집단환경변수를 범주화하여 대대급 부대의 성과평가를 수행하였다.

춘계와 하계의 영양염 농도와 그 구성비가 식물플랑크톤의 군집구조에 미치는 영향평가 (The Influence of Nutrients Concentration and the Ratio on Phytoplankton Community Structure during Late Spring and Early Summer in Sagami Bay, Japan)

  • 백승호;시모데신지;한명수;키쿠치토모히코
    • ALGAE
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    • 제23권4호
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    • pp.277-288
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    • 2008
  • The relationship between nutrients and phytoplankton dynamics was investigated daily from 12 April to 22 July 2003 in Sagami Bay, Japan. According to multidimensional scaling (MDS) and cluster analysis, phytoplankton community was divided into four distinct groups. The first group was consisted of centric diatom species, such as Guinardia spp., Detonula spp., Letocylindrus danicus, Skeletonema costatum, Eucampia zodiacus and Chaetoceros spp.. The second and third clusters comprised mainly diatoms and dinoflagellates, respectively. The other cluster was restricted to the samples collected during the last sampling period when the rainfall and river discharge was frequently recorded. Canonical correspondence analysis (CCA) was applied to analyze four groups respectively, which focused on the effects of nutrients concentration and ratio on phytoplankton variations. Based on CCA analysis, most species of centric diatom were negatively correlated with DSi concentrations and Si/N ratio. Nutrients were strongly limited phytoplankton growth during the summer when the rainfall was not observed, whereas river discharge by rainfall and counterclockwise coastal currents (although the surface circulation pattern is often altered by Kuroshio Current, the counterclockwise coastal currents are generally dominant) has brought phytoplankton population accumulation and triggered the micoalgae growth in western part of the bay. Phosphorous (P) was strongly limited after significantly increases in the phytoplankton abundances. However, silicate (Si) was not a major limiting factor for phytoplankton production, since Si/DIN and Si/P ratio did not create any potential stoichiometric limitation. This indicates that high Si availability contributes favorably to the maintenance of diatom ecosystems in Sagami Bay.

IL-34 Aggravates Steroid-Induced Osteonecrosis of the Femoral Head via Promoting Osteoclast Differentiation

  • Feng Wang;Hong Sung Min;Haojie Shan;Fuli Yin;Chaolai Jiang;Yang Zong;Xin Ma;Yiwei Lin;Zubin Zhou;Xiaowei Yu
    • IMMUNE NETWORK
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    • 제22권3호
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    • pp.25.1-25.11
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    • 2022
  • IL-34 can promote osteoclast differentiation and activation, which may contribute to steroid-induced osteonecrosis of the femoral head (ONFH). Animal model was constructed in both BALB/c and IL-34 deficient mice to detect the relative expression of inflammation cytokines. Micro-CT was utilized to reveal the internal structure. In vitro differentiated osteoclast was induced by culturing bone marrow-derived macrophages with IL-34 conditioned medium or M-CSF. The relative expression of pro-inflammation cytokines, osteoclast marker genes, and relevant pathways molecules was detected with quantitative real-time RT-PCR, ELISA, and Western blot. Up-regulated IL-34 expression could be detected in the serum of ONFH patients and femoral heads of ONFH mice. IL-34 deficient mice showed the resistance to ONFH induction with the up-regulated trabecular number, trabecular thickness, bone value fraction, and down-regulated trabecular separation. On the other hand, inflammatory cytokines, such as TNF-α, IFN-γ, IL-6, IL-12, IL-2, and IL-17A, showed diminished expression in IL-34 deficient ONFH induced mice. IL-34 alone or works in coordination with M-CSF to promote osteoclastogenesis and activate ERK, STAT3, and non-canonical NF-κB pathways. These data demonstrate that IL-34 can promote the differentiation of osteoclast through ERK, STAT3, and non-canonical NF-κB pathways to aggravate steroid-induced ONFH, and IL-34 can be considered as a treatment target.

환경변화에 따른 웅천천의 어류상과 어류 군집 특성 (Characteristics of Fish Fauna and Community Structure in Ungcheon Stream due to the Environmental Changes)

  • 정화영;김경환;송미영;이완옥
    • 한국환경생태학회지
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    • 제28권3호
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    • pp.314-325
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    • 2014
  • 충남 보령시의 웅천천에 설치된 댐(어도 설치)과 대형 보(어도 미설치), 그리고 상류지역의 인근 폐광이 어류군집에 미치는 영향에 대해 알아보기 위하여 2011년 4월부터 10월까지 4회에 걸쳐 10개 지점의 어류상을 조사하였다. 총 12과 36종의 어류가 채집되었으며 우점종은 Zacco platypus(23.4%), 아우점종은 Zacco koreanus(20.5%) 였다. 고유종은 10종(27.8%)이었으며, 외래도입종인 Micropterus salmoides가 출현하였다. 유사도분석 결과 상류인 St.1, St.2, St.3, 중류인 St.4, St.5, St.6, St.7 하류인 St.8, St.9, St.10의 세 그룹으로 구분되었다. 어도가 설치된 보령댐의 상하류 지점간(St.6-St.7)의 군집유사도는 높았으나, 어도가 설치되지 않은 대형보의 상하류 지점간(St.7-St.8)의 유사도는 매우 낮아 어도의 설치가 필요하였다. 정준상관분석 결과, 웅천천의 환경조건은 일반적인 하천과는 달리 상류에서 전기전도도와 염도가 높게 나타났으며 이러한 환경에서 Misgurnus mizolepis 외에 고유종인 Silurus microdorsalis, Coreoleuciscus splendidus, Iksookimia koreensis 등이 서식하고 있었다. 하폭이 크고 유속이 느린 하류역에는 외래도입종인 M. salmoides 외에 고유종인 Squalidus gracilis majimae 이 동소적으로 출현하고 있어 이들을 위한 보호 대책이 필요하였다.

NONEXISTENCE OF A CREPANT RESOLUTION OF SOME MODULI SPACES OF SHEAVES ON A K3 SURFACE

  • Choy, Jae-Yoo;Kiem, Young-Hoon
    • 대한수학회지
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    • 제44권1호
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    • pp.35-54
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    • 2007
  • Let $M_c$ = M(2, 0, c) be the moduli space of O(l)-semistable rank 2 torsion-free sheaves with Chern classes $c_1=0\;and\;c_2=c$ on a K3 surface X, where O(1) is a generic ample line bundle on X. When $c=2n\geq4$ is even, $M_c$ is a singular projective variety equipped with a holomorphic symplectic structure on the smooth locus. In particular, $M_c$ has trivial canonical divisor. In [22], O'Grady asks if there is any symplectic desingularization of $M_{2n}$ for $n\geq3$. In this paper, we show that there is no crepant resolution of $M_{2n}$ for $n\geq3$. This obviously implies that there is no symplectic desingularization.