• Title/Summary/Keyword: Slender body

Search Result 192, Processing Time 0.025 seconds

Interspecific hybridization in seahorses: artificially produced hybrid offspring of Hippocampus kuda and Hippocampus reidi

  • Han, Sang-Yun;Rho, Sum;Noh, Gyeong Eon;Kim, Jin-Koo
    • Fisheries and Aquatic Sciences
    • /
    • v.21 no.5
    • /
    • pp.11.1-11.8
    • /
    • 2018
  • Interspecific hybridization experiments were conducted between the common seahorse Hippocampus kuda (male) and the slender seahorse H. reidi (female) during artificial rearing to develop a new aquarium fish with unique polyandrous mating. Molecular analysis via mitochondrial DNA (mtDNA) cytochrome b and nuclear DNA (ncDNA) ribosomal protein S7 gene supported the hybridization between the two species, and the hybrid also showed morphological characteristics of both species. Juveniles of H. kuda have dense melanophores on the whole body or only on the trunk and tail, whereas juveniles of H. reidi have thin melanophores on the whole body or present in stripes only along their prominent trunk and tail rings. However, all the hybrid juveniles had dense melanophores only on the tail, with the striped trunk rings, thus showing an intermediate pattern, and these patterns were limited to the fairly early stage of development (1-10 days old). In contrast, the two eye spines in the hybrid were apparent after 9 days old, which were not inherited from H. kuda (one eye spine), but from H. reidi (two eye spines). According to LOESS (local regression) analysis, the growth rate increased between 20 and 25 days, and the hybrids grew faster than H. kuda when they entered the explosive second phase of growth between 25 and 45 days for all the seahorses. This study highlights the hybridization between H. kuda and H. reidi may contribute to the improved taxonomic information of young seahorses.

Paradraconema jejuense, a New Species of Genus Paradraconema (Nematoda: Draconematidae) from Korea (곁도마뱀선충속 (선형동물문: 도마뱀선충과)의 해양 선충류 1신종)

  • Rho Hyun Soo;Kim Won
    • Animal Systematics, Evolution and Diversity
    • /
    • v.21 no.1
    • /
    • pp.81-91
    • /
    • 2005
  • A new species of draconematid nematode, Paradraconema jejuense n. sp., is described from the shallow sublittoral coarse sediments of Jeju Island, Korea. Paradraconema jejuense n. sp. is most similar to P. antarcticum Allen and Noffsinger, 1978 in having similar habitus (long slender body) and amphideal fovea (doubled elongate spiral in male and circular spiral in female), but is distinguished by the following characteristics: larger number of posterior sublateral adhesion tubes (10 in male and 11-12 in female) and subventral adhesion tubes (16 in male and 17-18 in female), fewer cephalic acathiform setae on rostrum (a pair of small cephalic acathiform setae in both sexes), the absence of eye-spots, and the presence of a differentiated lateral field in mid-body region. This is the first taxonomic report on Paradraconema species from Korea.

A Study of Hydrodynamic Forces Acting on a Ship Hull Under Lateral Low Speed Motion (저속 횡 이동하는 선박의 선체에 작용하는 유체력에 관한 연구)

  • 이윤석;김순갑
    • Journal of the Korean Institute of Navigation
    • /
    • v.23 no.2
    • /
    • pp.29-42
    • /
    • 1999
  • An accurate method of estimating ship maneuverability needs to be developed to evaluate precisely and improve the maneuverability of ships according to the water depth. In order to estimate maneuverability by a mathematical model. The hydrodynamic forces acting on a ship hull and the flow field around the ship in maneuvering motion need to be estimated. The ship speed new the berth is very low and the fluid flow around a ship hull is unsteady. So, the transient fluid motion should be considered to estimate the drag force acting on the ship hull. In the low speed and short time lateral motion, the vorticity is created by the body and grow up in the acceleration stage and the velocity induced by the vorticity affect to the body in deceleration stage. For this kind of problem, CFD is considered as a goof tool to understand the phenomena. In this paper, the 2D CFD code is used for basic consideration of the phenomena to solve the flow in the cross section of the ship considering the ship is slender and the water depth is large enough. The flow fields Added and hydrodynamic forces for the some prescribed motions are computed and compared with the preliminary experiment results. The comparison of the force with measurement is shown a fairly good agreement in tendency. The 3D Potential Calculation based on the Hess & Smith Theory is employed to predict the surge, sway added mass and yaw added moment of inertia of hydrodynamic coefficients for M/V ESSO OSAKA according to the water depth. The results are also compared with experimental data. Finally, the sway added mass of hydrodynamic coefficients for T/S HANNARA is suggested in each water depth.

  • PDF

A study on the Survey of the Production Conditions and Improvement in the Fit of a Slim Fit Tailored Jacket - Focused on the Korean women in Their 30s - (슬림 핏 테일러드 재킷 생산 실태조사와 맞음새 향상을 위한 연구 - 국내 30대 여성 중심으로 -)

  • Jeong, Jae Chul
    • Fashion & Textile Research Journal
    • /
    • v.18 no.2
    • /
    • pp.216-224
    • /
    • 2016
  • Recently, the interest in a garment that accentuates a fit and slender body continues to be highly desirable. Customers frequently want to wear a slim designed jacket that fits well, reflecting the trends of being young and slim. Accordingly, this research collected information on brands with ready-to-wear slim fit tailored jackets that target female customers in their 30s. By identifying the jacket pattern design and production state by brand, and evaluating the appearance when wearing the jacket, I was able to draw up the following conclusions. First, the fit highlights many problems because of the difference between the model size of brands that targeted domestic women in their 30s and the standard somatotype of them. This can be solved by considering the somatotype of women in their 30s when choosing the models. Second, the relative simplicity of the pattern should allow a slim fit tailored jacket to be produced that fits the front, back and side well. This would lead to the development of a jacket that would fit better as well as allowing for ease of movement. Similar to this, the model size of domestic brands changes frequently and customers prefer the size of a slim model instead of the size suitable for a target's somatotype. This results in a limit on the levels of satisfaction regarding brand targets for body types. Accordingly, it is hoped that this research will become the standard data for the development of a slim fit tailored jacket that will fit women in their 30s well.

Fine Structure of the Sperm in the Myotis daubentonii ussuriensis (물윗수염박쥐(Myotis daubentinii ussuriensis)의 정자미세구조)

  • Kim, Hyun-Hee;Lee, Jung-Hun
    • Applied Microscopy
    • /
    • v.41 no.1
    • /
    • pp.31-35
    • /
    • 2011
  • The fine structures of the sperm morphology in the Myotis daubentonii ussuriensis were observed by transmission electron microscope. The results showed that the sperm head revealed bullet shaped, the width was showed a slender more than toward the posterior region to anterior region of nucleus. The sperm head was about $4.5{\mu}m$ in length, being about $2.0{\mu}m$ in width. The nuclear length was $4.3{\mu}m$, occupied most of the sperm head. The nucleus and acrosome were separated by the apical body. The neck region was composed the basal plate, capitulum and segmented columns. The segmented columns were about 12 to 14 in number and connected with the outer dense fibers of the middle piece. The mitochondria sheath were arranged like the thread of a screw, and the total number of mitochondrial gyres were 57. The satellite fibers were observed irregularly among the outer dense fibers in the middle piece. Except the middle piece they are not observed in the principal and end pieces of the tail. In general, the tail show axoneme composed of a 9+2 microtubular pattern, and microtubules of the end piece were arranged irregularly.

A Qualitative Study on the Psychological Meanings of Wearing Female High-Heeled Shoes (하이힐 착용 심리에 대한 질적 연구)

  • Cho, Sun-Myoung;Kim, Hee-Sun;Koh, Ae-Ran
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.33 no.9
    • /
    • pp.1361-1373
    • /
    • 2009
  • This study analyzed female motives and psychological experiences related with high-heeled shoes. Data was collected through in-depth interviews with seven females having more than forty pairs of high-heeled shoes. Exploratory data are classified into physical aspects and mental aspects, and the meaning of wearing high-heeled shoes were derived and discussed. First, with high-heeled shoes, the participants tried to make an ideal physical appearance, 1) to make an aesthetic illusion of a longer, more slender body 2) to make a more glamorous bodyline and toned legs. Second, the psychological experiences were as follows: 1) Wearing high-heeled shoes, they felt self-confidence in appearance and had feelings of satisfaction, fulfillment, and superiority. 2) High-heeled shoes gave wearers an increased sexual appearance in addition to a feminine attitude and independent mind. Accordingly, wearers thought they could make males compliant with a better sexual look in private and public life. 3) Through buying or putting on high-heeled shoes, women could change their mood, have mental stability, and channel sexual desires. 4) Some women made the secret self with the collected high-heeled shoes for sexual fantasies. 5) They thought that painful bodies or feet were not cumbersome. In addition, some wearers thought high-heeled shoes were a natural extension of their bodies.

Description of Diplotriaena manipoli (Nematoda: Diplotriaenoidea) Detected in the Body Cavity of Garrulus glandarius brandtii from Republic of Korea

  • Hong, Eui-Ju;Ryu, Si-Yun;Chae, Joon-Seok;Kim, Hyeon-Cheol;Park, Jinho;Cho, Jeong-Gon;Choi, Kyoung-Seong;Yu, Do-Hyeon;Park, Bae-Keun
    • Journal of Veterinary Clinics
    • /
    • v.36 no.3
    • /
    • pp.133-138
    • /
    • 2019
  • The present study was performed to identify the nematodes recovered from the Eurasian jay, Garrulus glandarius brandtii, from Daejeon Metropolitan City, the Republic of Korea. Total five nematode worms were detected in the body cavities of two out of the twenty birds necropsied, and they were identified using morphological features, light and scanning electron microscope (SEM), and molecular (18S rRNA analysis) methods. The nematodes were all female Diplotriaena manipoli and had numerous eggs at different developmental stages in the uterus. The nematodes were long and slender measuring about 123-145 mm. The eight submedian cephalic papillae were arranged into four large, outer papillae and four small, inner-circle papillae. A pair of amphidal pores were located at the lateral portion of the mouth. The manubrium apex of trident was rounded and three branches of trident were bluntly rounded at the posterior ends. Using 18S rRNA partial sequence arrangements, DNA analysis of nematode worms was also carried out, and they were identified to be close to the Serratospiculum tendo based on a phylogenic tree analysis. To our knowledge, this is the first report on the molecular characterization and SEM study of D. manipoli.

Seismic analysis and performance for stone pagoda structure under Gyeongju earthquake in Korea

  • Kim, Ho-Soo;Kim, Dong-Kwan;Jeon, Geon-Woo
    • Earthquakes and Structures
    • /
    • v.21 no.5
    • /
    • pp.531-549
    • /
    • 2021
  • Analytical models were developed and seismic behaviors were analyzed for a three-story stone pagoda at the Cheollyongsa temple site, which was damaged by the Gyeongju earthquake of 2016. Both finite and discrete element modeling were used and the analysis results were compared to the actual earthquake damage. Vulnerable parts of stone pagoda structure were identified and their seismic behaviors via sliding, rocking, and risk analyses were verified. In finite and discrete element analyses, the 3F main body stone was displaced uniaxially by 60 and 80 mm, respectively, similar to the actual displacement of 90 mm resulting from the earthquake. Considering various input conditions such as uniaxial excitation and soil-structure interaction, as well as seismic components and the distance from the epicenter, both models yielded reasonable and applicable results. The Gyeongju earthquake exhibited extreme short-period characteristics; thus, short-period structures such as stone pagodas were seriously damaged. In addition, we found that sliding occurred in the upper parts because the vertical load was low, but rocking predominated in the lower parts because most structural members were slender. The third-floor main body and roof stones were particularly vulnerable because some damage occurred when the sliding and rocking limits were exceeded. Risk analysis revealed that the probability of collapse was minimal at 0.1 g, but exceeded 80% at above 0.3 g. The collapse risks at an earthquake peak ground acceleration of 0.154 g at the immediate occupancy, life safety, and collapse prevention levels were 90%, 52%, and 6% respectively. When the actual damage was compared with the risk analysis, the stone pagoda retained earthquake-resistant performance at the life safety level.

Numerical Analysis of Vortex Induced Vibration of Circular Cylinder in Lock-in Regime (Lock-in 영역에서 원형실린더의 와류유기진동 전산해석)

  • Lee, Sungsu;Hwang, Kyu-Kwan;Son, Hyun-A;Jung, Dong-Ho
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.29 no.1
    • /
    • pp.9-18
    • /
    • 2016
  • The slender structures such as high rise building or marine riser are highly susceptible to dynamic force exerted by fluid-structure interactions among which vortex-induced vibration(VIV) is the main cause of dynamic unstability of the structural system. If VIV occurs in natural frequency regime of the structure, fatigue failure likely happens by so-called lock-in phenomenon. This study presents the numerical analysis of dynamic behavior of both structure and fluid in the lock-in regimes and investigates the subjacent phenomena to hold the resonance frequency in spite of the change of flow condition. Unsteady and laminar flow was considered for a two-dimensional circular cylinder which was assumed to move freely in 1 degree of freedom in the direction orthogonal to the uniform inflow. Fluid-structure interaction was implemented by solving both unsteady flow and dynamic motion of the structure sequentially in each time step where the fluid domain was remeshed considering the movement of the body. The results show reasonable agreements with previous studies and reveal characteristic features of the lock-in phenomena. Not only the lift force but also drag force are drastically increasing during the lock-in regime, the vertical displacement of the cylinder reaches up to 20% of the diameter of the cylinder. The correlation analysis between lift and vertical displacement clearly show the dramatic change of the phase difference from in-phase to out-of-phase when the cylinder experiences lock-in. From the results, it can be postulated that the change of phase difference and flow condition is responsible for the resonating behavior of the structure during lock-in.

Himasthla kusasigi(Tremtoda, Echinostomatidae) recovered from the Intestine of the Dunlin, Calidris alpina sakhalina, in Korea (한국산 민물도요(Calidris alpina sakhalina)의 장에서 발견된 흡층류 1미기록종(Himasthla kusasigi))

  • 주종필;조유정;유정칠;박성균
    • Animal Systematics, Evolution and Diversity
    • /
    • v.16 no.1
    • /
    • pp.125-131
    • /
    • 2000
  • This paper deals with the morphology and taxonomy of the first reported species of echinostome belonging to the genus Himasthla Dietz, 1909, found from dunlins (Calidris alpina sakhalina) in Korea. Birds were captured with mist-nets at the tidal flat of Yeochari, Kanghwa-gun, Kyunggi-do, Korea. The worms were removed from avian intestines in physiological saline, fixed, acetocarmine stained and observed. Himasthla kusasigi Yamaguti, which was found in 1939, was characterized morphologically by a long and slender body (5.27 mm in length), besetting with spines and reniform head collar (0.27 mm) in a form of a single and uninterrupted row of 31 spines. The oral sucker (0.057$\times$0.0684 mm) is smaller than the ventral sucker (0.35$\times$0.29 mm). The ventral sucker was close to the anterior extremity of the body. The worm had two elliptical testes (anterior 0.47$\times$0.30 mm, posterior 0.59$\times$0.27 mm). The testes were close to the posterior end of the body. The uterus was very long, winding and extending through at least two thirds of the body length. The ovary (0.13$\times$0.14mm) was round and small. Below the ovary, a round and small seminal receptacle was found.

  • PDF