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911.
Ten new species of cyclopoid copepods are described as parasites of marine fishes from Korea. Three new species of the family Bomolochidae are described as gill parasites: Orbitacolax pteragogi n. sp. from Pteragogus flagellifer (Valenciennes), Orbitacolax trichiuri n. sp. from Trichurus lepturus Linnaeus, and Orbitacolax unguifer n. sp. from Evynnis japonica Tanaka. Four species of the genus Colobomatus Hesse, 1873 of the family Philichthyidae are described as internal parasites: Colobomatus unimanus n. sp. from Pseudolabrus eoethinus (Richardson), Colobomatus recticaudatus n. sp. from Halichoeres poecilopterus (Temminck and Schlegel), Colobomatus floridus n. sp. from Hapalogenys mucronatus (Eydoux and Souleyet), and Colobomatus orientalis n. sp. from Johnius grypotus (Richardson). Three new species of the family Taeniacanthidae, including a new species belonging to a new genus, are described as gill parasites: Taeniacanthus singularis n. sp. from Halieutaea fumosa Alcock, Triacanthus luteus n. gen. n. sp. from Odontamblyopus lacepedii (Temminck and Schlegel), and Umazuracola geminus n. sp. from Stephonolepis cirrhifer (Temminck and Schlegel). 相似文献
912.
Bo-Ram Ye Junseong Kim Min-Sun Kim Jiyi Jang Chulhong Oh Do-Hyung Kang Zhong-Ji Qian Won-Kyo Jung Il-Whan Choi Soo-Jin Heo 《Ocean Science Journal》2013,48(4):339-348
We demonstrated that an extract from Pylaiella littoralis, collected from the Federate States of Micronesia (FSM), could inhibit the proliferation of tumor cells. P. littoralis extract (PLE) showed anti-proliferative activities in the tumorigenic cells tested, ranging from 20.2% to 67.9%. The highest inhibitory activity, in HT-29 cells, was selected for further experiments. PLE showed no cytotoxic effect in normal cells and inhibited the growth of HT-29 cells depending on concentration and incubation time. PLE-treated HT-29 cells showed the typical morphological characteristics of apoptosis, such as apoptotic body formation and DNA fragmentation. PLE also induced mitochondrial membrane potential depolarization and resulted in increased mitochondrial membrane permeability, compared with untreated cells. PLE decreased Bcl-2 protein and increased Bax protein expression, activating caspase-3 and poly (ADP-ribose) polymerase (PARP) expression via the caspase pathway. PLE also increased the phosphorylation of c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase (ERK), and it reduced cell viability in treatment cells with specific inhibitors such as PD98059 (a specific inhibitor of ERK), SP600125 (a specific inbibitor of JNK), and SB 203580 (a specific inbibitor of p38 MAPK). via the the mitogen-activated protein kinases (MAPKs) pathway. These results suggest that PLE inhibits the proliferation of HT-29 cells by affecting the caspase and MAPK pathways involved in the induction of apoptosis. Thus, we suggest that P. littoralis extract might be potential candidate agents for the treatment of human colorectal cancer. 相似文献
913.
Jae-Hoon Cha Kwang-Bae Kim Ji-Na Song In-Soo Kim Jeong-Bin Seo Chul-Hwi Kwoun 《Ocean Science Journal》2013,48(4):319-328
This study was carried out to learn about differences in the sessile macrobenthic fauna communities between the artificial and natural habitats. There were some differences in terms of species composition and dominant species and community structure between two habitat types. The dominant species include Pollicipes mitella and Granuilittorina exigua in natural rocky intertidal zones; Monodonta labio confusa, Ligia exotica, Tetraclita japonica in the artificial rocky intertidal zones. Among all the species, L. exotica and T. japonica occurred only in the artificial rocky intertidal zone. The results of cluster analysis and nMDS analysis showed a distinct difference in community structure between artificial and natural rocky intertidal zones. The fauna in the natural rocky intertidal zones were similar to each other and the fauna in the artificial rocky intertidal zones were divided depending on the slope of the substratum. In the case of a sloping tetrapod, M. labio confusa and P. mitella were dominant, but at the vertical artificial seawall, Cellana nigrolineata, L. exotica T. japonica were dominant. The analysis of the species presented in natural and artificial rocky intertidal areas showed the exclusive presence of 10 species on natural rocks and 12 species on artificial rocks. The species in the natural rocky intertidal area included mobile gastropods and cnidarians (i.e. rock anemones), and the species in the artificial rocky intertidal area mostly included non-mobile attached animals. The artificial novel structure seems to contribute to increasing the heterogeneity of habitats for marine invertebrate species and an increase the species diversity in rocky coastal areas. 相似文献
914.
915.
Eight species of the Hatschekiidae are recorded as parasites of marine fishes from southern coast of Korea. One new species, Hatschekia jejuensis, parasitic on Cheilodactylus zonatus Cuvier is included. The remaining seven species are new to Korean fauna: Hatschekia iridescens Wilson, 1913, H. japonica Jones, 1985, H. monacanthi Yamaguti, 1939, H. tenuis (Heller, 1865) H. pseudolabri Yamaguti, 1953, H. cylindrica Shiino, 1957, and Pseudocongericola chefoonensis Yü, 1933. Hatschekia jejuensis n. sp. has a combination of characteristics in the female where the trunk is 2.35 times as long as the cephalothorax and displays a pair of posterolateral bulges on both sides, the antennules is 5-segmented, the mandible bears six teeth, and the armature formulae of the legs are I-0; III (exopod) and 0-0; II (endopod) for leg 1 and I-0; I (exopod) and 0-0; II (endopod) for leg 2. 相似文献
916.
An Suk Lim Hae Jin Jeong Tae Young Jang Nam Seon Kang Sung Yeon Lee Yeong Du Yoo Hyung Seop Kim 《Ocean Science Journal》2013,48(1):1-17
Prorocentrum spp. are planktonic and/or benthic species. Benthic Prorocentrum species are of primary concern to scientists and the public because some of them are toxic. We established clonal cultures of 3 strains of Prorocentrum species that were collected from the thalli of a macroalga in the coastal waters off Jeju Island, located at the southern end of Korea. The Korean strains of P. cf. rhathymum, which are morphologically almost identical to the Virgin Island strain of P. rhathymum, were different from P. mexicanum because the former dinoflagellate has one simple collar-like spine in the periflagellar area, while the latter dinoflagellate has a 2- or 3-horned spine. In addition, the sequences of the small subunit (SSU) rDNA of the Korean strains were identical to those of the Malaysian and Floridian strains of P. rhathymum, while the sequences of the large subunit (LSU) rDNA of the Korean strains were 0.1–0.9% different from those of the Iranian and Malaysian strains of P. rhathymum. In phylogenetic trees based on the SSU rDNA sequences, the Korean strains of P. rhathymum formed a clade with the Malaysian and Floridian strains of P. rhathymum and the Vietnamese and Polynesian strains of P. mexicanum. However, in phylogenetic trees based on the LSU rDNA sequences, the Korean strains of P. rhathymum formed a clade with the Iranian strain of P. rhathymum and the Spanish and Mexican strains of P. mexicanum. Therefore, the molecular characterization of the Korean strains does not allow us to clearly classify them as P. rhathymum, nor P. mexicanum, although their morphology has so far been reported to be closer to that of P. rhathymum than P. mexicanum and thus we designated them as P. cf. rhathymum. 相似文献
917.
For over 30 years, IHP (International Hydrological Programme) has been actively operating as a UNESCO’s (United Nations Educational,
Scientific and Cultural Organization) international scientific cooperative programme in water research, water resources management,
education and capacity-building, and the only broadly-based science programme of the UN (United Nations) system in this region.
By a number of initiatives and networks, the IHP has progressively carried out activities on the quantity and quality of global/regional
water resources, transboundary water resources management, mitigation of water related hazards, and water education. While
addressing comprehensive areas over water challenges, greater emphasis has been placed on the role of water resources management
for sustainable development and with respect to the expected changes in climate and environmental conditions. WWAP (World
Water Assessment Programme) and its major product WWDR (World Water Development Report) in East Asia are under the framework
of IHP which supports field oriented activities on monitoring freshwater, developing case studies, enhancing national assessment
capacity, and facilitating decision making processes. In light of transboundary waters in IHP, RSC (Regional Steering Committee)
plays a focal role for facilitating regional cooperation in the Southeast and East Asia and Pacific States. Furthermore, ISI
(International Sediment Initiative) and IFI (International Flood Initiative) have significant roles, respectively, for the
management of erosion and sedimentation in line with river system or reservoir management, and for the flood management focusing
on capacity building of each country in East Asia. There are other major areas of concern under UNESCO’s IHP programme in
East Asia, specifically in aspects including, mitigating water conflicts on transboundary aquifers through ISARM (International
Shared Aquifer Resources Management), water management of arid areas through Water and Development Information for Arid Lands-
A Global Network (Asian G-WADI), and sustainable management of groundwater by UNESCO Water Chair, as well as water education
through the programme of Sustainable Water Integrated Management-Educational Component.
Author: Ramasamy Jayakumar, native of India, Ph.D, specialized in application of remote sensing, GIS, geo-statistical methods in
hydrogeological modelling and irrigation water management. 相似文献
918.
H. S. Kim K. H. Lee M. S. Kyoung B. Sivakumar E. T. Lee 《Stochastic Environmental Research and Risk Assessment (SERRA)》2009,23(7):907-916
It has been a common practice to employ the correlation dimension method to investigate the presence of nonlinearity and chaos
in hydrologic processes. Although the method is generally reliable, potential limitations that exist in its applications to
hydrologic data cannot be dismissed altogether. As for these limitations, two issues have dominated the discussions thus far:
small data size and presence of noise. Another issue that is equally important, but less discussed in the literature, is the
selection of delay time (τ
d
) for reconstruction of the phase-space, which is an essential first step in the correlation dimension method, or any other
chaos identification and prediction method for that matter. It has also been increasingly recognized that fixing the delay
time window (τ
w
) rather than just the delay time itself could be more appropriate, since the delay time window is the one that is of actual
interest at the end to represent the dynamics. To this effect, Kim et al. (1998a) [Phys Rev E 58(5):5676–5682] developed a procedure for fixing the delay time window and demonstrated its effectiveness on
three artificial chaotic series, and followed it up with the development of the C–C method to estimate both the delay time
and the delay time window. The purpose of the present study is to test this procedure on real hydrologic time series and,
hence, to assess their nonlinear deterministic characteristics. Three hydrologic time series are studied: (1) daily streamflow
series from St. Johns near Cocoa, FL, USA; (2) biweekly volume time series from the Great Salt Lake, UT, USA; and (3) daily
rainfall series from Seoul, South Korea. The results are also compared with those obtained using the conventional autocorrelation
function (ACF) method. 相似文献
919.
Michael H. Stevens Christoph R. Englert Mark Hervig Svetlana V. Petelina Werner Singer Kim Nielsen 《Journal of Atmospheric and Solar》2009,71(3-4):401-407
We present the first measurement of polar mesospheric cloud (PMC) occurrence frequency over the diurnal cycle from a satellite. The observations are made during the 2007 northern hemisphere PMC season by the Spatial Heterodyne IMager for MEsospheric Radicals (SHIMMER), which views the limb near 309 nm typically between 34 and 98 km. The PMC diurnal variation is derived between 50 and 58°N, where local times at the tangent point precess by ~30 min/day allowing for observations between 0330 and 2130 local time during the PMC season. We find that the occurrence frequencies exhibit a strong semidiurnal behavior with peaks near 0600 and 1800 local time and a minimum between 0900 and 1600 during which they are on average an order of magnitude less. The semidiurnal dependence is strongly correlated with concurrent ground-based measurements of meridional winds and temperatures measured at the same latitude. Our results for PMC frequency over the diurnal cycle can be used to help reconcile observations from other satellites that only permit cloud measurements at discrete local times. 相似文献
920.
High-altitude data assimilation system experiments for the northern summer mesosphere season of 2007 总被引:1,自引:0,他引:1
Stephen D. Eckermann Karl W. Hoppel Lawrence Coy John P. McCormack David E. Siskind Kim Nielsen Andrew Kochenash Michael H. Stevens Christoph R. Englert Werner Singer Mark Hervig 《Journal of Atmospheric and Solar》2009,71(3-4):531-551
A global numerical weather prediction system is extended to the mesosphere and lower thermosphere (MLT) and used to assimilate high-altitude satellite measurements of temperature, water vapor and ozone from MLS and SABER during May–July 2007. Assimilated temperature and humidity from 100 to 0.001 hPa show minimal biases compared to satellite data and existing analysis fields. Saturation ratios derived diagnostically from these assimilated temperature and water vapor fields at PMC altitudes and latitudes compare well with seasonal variations in PMC frequency measured from the aeronomy of ice in the mesosphere (AIM) satellite. Synoptic maps of these diagnostic saturation ratios correlate geographically with three independent transient mesospheric cloud events observed at midlatitudes by SHIMMER on STPSat-1 and by ground observers during June 2007. Assimilated temperatures and winds reveal broadly realistic amplitudes of the quasi 5-day wave and migrating tides as a function of latitude and height. For example, analyzed winds capture the dominant semidiurnal MLT wind patterns at 55°N in June 2007 measured independently by a meteor radar. The 5-day wave and migrating diurnal tide also modulate water vapor mixing ratios in the polar summer MLT. Possible origins of this variability are discussed. 相似文献