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        검색결과 621

        381.
        2011.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We present two large cosmological N-body simulations, called Horizon Run 2 (HR2) and Horizon Run 3 (HR3), made using 60003 = 216 billions and 72103 = 374 billion particles, spanning a volume of (7.200 h-1Gpc)3 and (10.815 h-1Gpc)3, respectively. These simulations improve on our previous Horizon Run 1 (HR1) up to a factor of 4.4 in volume, and range from 2600 to over 8800 times the volume of the Millennium Run. In addition, they achieve a considerably finer mass resolution, down to 1.25 X 1011h-1M⊙, allowing to resolve galaxy-size halos with mean particle separations of 1.2h-1Mpc and 1.5h-1Mpc, respectively. We have measured the power spectrum, correlation function, mass function and basic halo properties with percent level accuracy, and verified that they correctly reproduce the CDM theoretical expectations, in excellent agreement with linear perturbation theory. Our unprecedentedly large-volume N-body simulations can be used for a variety of studies in cosmology and astrophysics, ranging from large-scale structure topology, baryon acoustic oscillations, dark energy and the characterization of the expansion history of the Universe, till galaxy formation science - in connection with the new SDSS-III. To this end, we made a total of 35 all-sky mock surveys along the past light cone out to z = 0.7 (8 from the HR2 and 27 from the HR3), to simulate the BOSS geometry. The simulations and mock surveys are already publicly available at http://astro.kias.re.kr/Horizon-Run23/.
        5,200원
        382.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The aim of this study was to evaluate the post-thawed characteristics of leopard cat semen. In this experiment, semen was collected from two leopard cats (A and B) at wild animal center in Seoul Grand Park in Korea. After collection, the sperms were washed with D-PBS and diluted by the freezing medium (Irvine science, USA) and stored in liquid nitrogen. The post-thawed concentration was for A and for B. The viability of post-thawed sperm from A and B individual was 24.0% and 19.0%, respectively. Pre-freezing motility of A and B individual semen was 68.54% and 56.65. Leopard cat A had more normal sperm than that of B (69.5% vs. 54.5%). Acrosome integrity analysis detected live (14.5% vs. 9.0%), damage (39.0% vs. 44.0%) and dead (46.0% vs. 47.0%) in leopard cat A and B, respectively. The present results concluded that leopard cat semen can be collected successfully by electro-ejaculation method and cryopreserved successfullyfor future use in different assisted reproductive technologies. The cryopreservation protocol needs to be modified for increasing post-thawed viability of leopard cat spermatozoa.
        4,000원
        387.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Seabirds have adapted to life in marine environments. More than 25% of the bird species observed in South Korea are seabirds, using the coast area of Korean peninsula as a stop-over and wintering, and breeding site. The aims of this review are to provide
        4,500원
        388.
        2011.06 구독 인증기관 무료, 개인회원 유료
        Clinical arthritis is typically divided into rheumatoid arthritis (RA) and osteoarthritis (OA). Arthritis-induced muscle weakness is a major problem in aged people, leading to a disturbance of balance during the gait cycle and frequent falls. The purposes of the present study were to confirm fiber type-dependent expression of muscle atrophy markers induced by arthritis and to identify the relationship between clinical signs and expression of muscle atrophy markers. Mice were divided into four experimental groups as follows: (1) negative control (normal), (2) positive control (CFA+acetic acid), (3) RA group (CFA+acetic acid+type Ⅱ collagen), and (4) aging-induced OA group. DBA/1J mice (8 weeks of age) were injected with collagen (50 μg/kg), and physiological (body weight) and pathological (arthritis score and paw thickness) parameters were measured once per week. The gastrocnemius muscle from animals in each group was removed, and the expression of muscle atrophy markers (MAFbx and MuRF1) and myosin heavy chain isoforms were analyzed by reverse transcription-polymerase chain reaction. No significant change in body weight occurred between control groups and collagen-induced RA mice at week 10. However, bovine type Ⅱ collagen induced a dramatic increase in clinical score or paw thickness at week 10 (p<0.01). Concomitantly, the expression of the muscle atrophy marker MAFbx was upregulated in the RA and OA groups (p<0.01). A dramatic reduction in myosin heavy chain (MHC)-Iβ was seen in the gastrocnemius muscles from RA and OA mice, while only a slight decrease in MHC-Ⅱb was seen. These results suggest that muscle atrophy gene expression occurred in a fiber type-specific manner in both RA- and OA-induced mice. The present study suggests evidence regarding why different therapeutic interventions are required between RA and OA.
        4,000원
        389.
        2011.06 구독 인증기관 무료, 개인회원 유료
        Arthritis is a common disease in aged people, and is clinically divided into rheumatoid arthritis (RA) and osteoarthritis (OA). Although common symptoms such as pain are present, the underlying pathological mechanisms are slightly different. Therefore, the objectives of the present study were to compare joint damage induced by RA and OA by analyzing the major morphological and molecular differences, and to propose a suitable therapeutic intervention based on the pathophysiological conditions of bones and joints. For the RA animal model, 8-week-old DBA1/J mice were immunized with bovine type II collagen emulsified in complete Freund’s adjuvant (CFA). Normal C57BL/6 mice (over 2 years of age) were used for OA. The clinical arthritis score was calculated using a subjective scoring system, and paw thicknesses were measured using calipers. The serum TNFα level was analyzed using an ELISA kit. Micro- CT was used to identify pathological characteristics and morphological changes. In collagen-induced RA mice, there were increased ankle joint volumes and clinical scores (p<0.01). The concentration of TNFα was significantly increased from 3 to 7 weeks after immunization. Micro-CT images showed trabecular bone destruction, pannus formation, and subchondral region destruction in RA mice. OA among aged mice showed narrowed joint spaces and breakdown of articular cartilage. This study suggests that a careful therapeutic intervention between RA and OA is required, and it should be based on morphological alteration of bone and joint.
        4,000원
        390.
        2011.06 구독 인증기관 무료, 개인회원 유료
        Peripheral nerve injuries are very common in clinics and often result in severe functional deficits. The aim of this study was to evaluate the effect of treadmill running and electro-acupuncture on nerve regeneration and functional recovery of muscle activity following sciatic nerve crush injury in a rat model. A comparative study was conducted over 30 days on 60 adult male Sprague-Dawley rats grouped into sham control (C), electro-acupuncture (EA), treadmill (T), and treadmill plus electro-acupuncture (TEA). The left sciatic nerve was crushed for 30 sec using a hemostatic forceps and functional activity was evaluated with sciatic functional tests, nerve conduct velocity, muscle weight, and histology at 10, 20, and 30 days after injury. Muscle weight was significantly (P<0.05) increased between days 10 and 30 in the TEA group. In histology, the degree of damage was scored as C > TEA > T > EA, although necrosis and fibrosis of muscle was observed only in the TEA group. The EA and TEA groups showed rapid recovery with better myelinated axons on day 10. These results suggest that application of the TEA method with balanced exercise is a useful treatment option for peripheral nerve injury regeneration and muscle activity.
        4,000원
        391.
        2011.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study three types of domatia; Tuft (T), Pocket-Tuft (PT) and Pocket (P) were observed on some species of the genus Cornus. Cornus officinalis Sieb & Zuee and C. florida Linnaeus possess T type, C. controversa Hemsl and C. walteri Wangerin possess PT type while C. alba Linnaeus possess P type. A total of 120 leaves were investigated for foliar mite’s population. T type domatia was the habitat of 329 mites (48.89%), followed by PT type where 198 mites (29.41%) were found, and the least favored was the P type domatia that accommodated 146 mites (21.70%) out of 673 mites in total. The mean number of mites per domatia was 8(±0.22), 4(±0.95) and 3(±0.70) for T, PT and P type, respectively. The alternative hypothesis that foliar mites prefer T type domatia as a habitat than PT and P type domatia was accepted based on these findings at a probability of P<0.05. Thus, it was concluded that foliar mites prefer T type domatia than the other two types. This could be due to the nature and efficiency of T type domatia in ensuring mites protection from predators and unfriendly environmental conditions. Therefore, the presence of denser tufts lowers the risks of predation and unfriendly environmental conditions and results in a higher number of mites.
        4,000원
        395.
        2011.05 구독 인증기관·개인회원 무료
        Reported herein is the use of mycotized millet grains with entomopathogenic fungi applied to soil to control western flower thrips (WFT), Franklinella occidentalis. The majority of mature larvae move from plants to soil for pupation. Mycotized millet grains with Beauveria bassiana ERL1170 and Metarhizium anisopliae ERL1171 were mixed in the upper layer of potting soil containing a blossomed marigold as a banker plant. B. bassiana GHA, a commercial isolate, served as a control. One week post applicaion 3 mated WFT females were added per plant. At 8 wks post infestation WFT mortality in pots with ERL1170 and ERL1171 treatments was 90% and 81% respectively compared to GHA with 15% mortality. Plants in the two ERL treatments had lower levels of damage. The insecticidal activities were positively associated with the fungal soil colonization. No significant release of fungal innoculum from the potting medium was observed. These results suggest that soil applications of entomopathogenic fungi can reduce WFT populations to significantly low levels by targeting pupae. Application timing and the life cycle of WFT are important considerations.
        396.
        2011.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this case report, we investigated the effects of robot-assisted gait therapy in a chronic stroke patient using motor assessment and gait analysis. A patient who suffered from the right hemiparesis following the left corona radiata and basal ganglia infarction received 30 minutes of robot-assisted gait therapy, 3 times a week for 4 weeks. Outcome was measured using Motoricity index(MI), Fugl-Meyer assessment(FMA), modified motor assessment scale(MMAS), isometric torque, body tissue composition, 10-meter gait speed and gait analysis. After robot-assisted gait therapy, the patient showed improvement in motor functions measured by MI, FMA, MMAS, isometric torque, skeletal muscle mass, 10-meter gait speed. In gait analysis, cadence, single support time, double support time, step length, walking speed improvement in after robot-assisted gait therapy. The results of this study showed that robot-assisted gait therapy is considered to facilitate locomotor recovery of the chronic hemiparetic stroke patient.
        4,000원
        397.
        2010.12 구독 인증기관 무료, 개인회원 유료
        A nine-month-old male Pekingese weighing 5.7 kg was admitted to the Veterinary Medical Center at Chungbuk National University with a history of acute nonambulatory tetraparesis after minor trauma. A diagnosis of atlantoaxial instability with a dens axis fracture was based on examination of survey spinal radiographs and was confirmed during surgery. A modified ventral fixation technique using cortical screws was used for stabilization of the atlantoaxial joint. Serial evaluation based on radiographic and neurologic assessment was performed eight weeks after surgery. Symptoms of tetraparesis disappeared gradually, and arthrodesis of the atlantoaxial joint using a ventral fixation technique has maintained stable fixation.
        4,000원
        398.
        2010.12 KCI 등재 구독 인증기관·개인회원 무료
        Addition of ammonia or any nitrogenous materials to the soil that release ammonia causing alkaline condition during decomposition stimulates the fruiting of a particular chemoecological group of fungi, called ammonia fungi (Sagara 1975). The study of ammonia fungi by artificial application of urea in forest soil has been done in diverse geographical regions such as in Japan, Taiwan, New Zealand, Western Australia, and UK. Up to date about 70 species of ammonia fungi have been recorded in those regions. However, ammonia fungi in the boreal forest of American continent have not yet been investigated. Thus, we collected the soils of A0 and the upper layer of HA horizons in plant pots from aspen forest near Edmonton, Canada. Thereafter, we applied urea (granular fertilizer; 46% nitrogen, 10 mg/g dry soil) in plant pots and incubated at 25˚C under 12 hours dark and light regime. After 40 days of incubation, several basidiomata of Coprinopsis species appeared. Among them one specimen was identified as C. rugosobispora based on macro- and microscopic features. Morphologically this species was very similar to C. phlyctidospora which was characterized by warty, ovoid basidiospores, and diverticulate veil elements. C. phlyctidospora has 4-spored basidia while C. rugosobispora had only 2-spored. In the beginning, it was thought probably it was only a 2-spored form of C. phlyctidospora. The basidiospore of C. rugosobispora (9.8-11.7×8.3-9.6㎛) was distinctly larger than that of C. phlyctidospora (8.4-10.6×6.0-7.6 ㎛). It was therefore separated from the C. phlyctidospora. Furthermore in this study we investigated its phylogenetic relationship based on the nuclear rDNA sequence in ITS regions and mating reactions among its close allies and further confirmed it as a distinct species. This is the first record of C. rugosobispora from American continent since it has been collected only from Europe (Belgium and Netherlands). Although urea effectively stimulated its occurrence but it has not yet been reported any other urea application studies so far. This indicates it is a new record in ammonia fungi as well.