706 research outputs found

    Geochemistry of late miocene-pleistocene basalts in the Phu Quy island area (East Vietnam Sea): Implication for mantle source feature and melt generation

    Get PDF
    The chemical compositions of late Miocene - Pleistocene basalts in Phu Quy island defines two major geochemical groups that reflect the formation and development of the island. The early low alkaline, TiO2 and P2O5, and high SiO2 group, comprising olivine and tholeiitic basalts, forms the base of the island. The later high alkaline, TiO2, and P2O5, and low SiO2 group, produced by central-type volcanic eruptions consisting of alkaline olivine and olivine basalts, overlies the early eruptive group. Crustal contamination may be expressed by the positive correlation between Ba/Nb and SiO2, which are higher in early eruptive basalts, possibly reflecting the involvement of crustal material, either in the source region or interaction of the melt on the way to the surface. However, negative relationship between Ba and SiO2, and positive correlation between Nb/Y and Zr/Y observed for two basaltic series may reflect the effect of melting pressures and degrees of partial melting. Methods of calculating the primitive basaltic melts based on the principle of olivine incremental additions to the basalt until the composition is equilibrated with the residual olivine at Fo89-90 may be used. The computed results show that the early basalts were generated under pressures of about 18-20 Kb (ca. 55-60 km) and the later basalts were formed in the pressure range of 20 to 25 Kb (corresponding to the depths about 60 to 75 km). The close range of melting pressures suggests decompression polybaric melting of a mantle source, which allows for mixing of various melt portions, resulting in the formation of geochemically linear relationship. It has been demonstrated that the post-opening volcanism was unrelated to an important tectonic phase and that the calculated extension factor (b) for the regional major extension fault systems is not significant (ca. 1.3) to trigger mantle melting. Therefore, the infiltration of asthenospheric flows resulting from the Neo-Tethys closure following the collision between India and Eurasia in the late Tertiary, may not only raise the mantle temperature leading to the melting but also appear to be the major driving force of marginal sea opening in the western Pacific, including the East Vietnam Sea.ReferencesBaker M.B., Hirschmann M.M., Ghiorso M.S., Stolper E.M., 1995. Compositions of near-solidus peridotite melts from experiments and thermodynamic calculations. Nature 375, 308-311. Baker M.B., Stolper E.M., 1994. Determining the composition of high pressure mantle melts using diamond aggregates. Geochimica et Cosmochimica Acta 58, 2811-2827. Carter A., Roques D., Bristow C.S., 2000. Denudation history of onshore central Vietnam: constraints on the Cenozoic evolution of the western margin of the South China Sea. Tectonophysics 322, 265-277. Ding W., Li J., Clift P.D., Expedition I.O.D.P., 2016. Spreading dynamics and sedimentary process of the Southwest Sub-basin, South China Sea: constraints from multi-channel seismic data and IODP Expedition 349. Journal of Asian Earth Sciences, 115, 97-113. Fitton J.G., Saunders A.D., Norry M.J., Hardarson B.S., Taylor R.N., 1997. Thermal and chemical structure of the Iceland plume. Earth and Planetary Science Letters 153, 197-208. Flower M.F.J., Zhang M., Tu K., Xie G.H., Chen C.Y., 1992. Magmatism in the South China Basin 2.Post-spreading Quaternary basalts from Hainan Island, south China. Chemical Geology 97, 65-87. Flower M., Tamaki K., Hoang N., 1998. Mantle Extrusion: A model for Dispersed Volcanism and DUPAL-like Asthenosphere in East Asia and the Western Pacific. In: Mantle dynamics and plate Interactions in East Asia, edited by: Flower, M et al. Geodynamic 27, 67-88. Flower M.F.J., Russo R.M., Tamaki K., Hoang Nguyen, 2001. Mantle contamination and the Izu-Bonin-Mariana (IBM) ‘high-tide mark’, evidence for mantle extrusion caused by Tethyan closure. Tectonophysics 333, 9-34. Franke D., Savva D., Pubellier M., Steuer S., Mouly B., Auxietre J.L., Meresse F., Chamot L.R., 2013. The final rifting evolution in the South China Sea. Marine and Petroleum Geology xxx, 1-17. Fyhn M.B.W., Boldreel L.O., Nielsen L.H., 2009. Geological development of the Central and South Vietnamese margin: implications for the establishment of the South China Sea, Indochinese escape tectonics and Cenozoic volcanism. J. Tectonophysics, 478 (3-4), 184-214. Hirose K., Kushiro I., 1993. Partial melting of dry peridotites at high pressures: determination of compositions of melts segregated from peridotite using aggregates of diamond. Earth and Planetary Science Letters 114, 477-489. Hofmann A.W., 1988. Chemical differentiation of the Earth: the relationship between mantle, continental crust, and oceanic crust. Earth and Planetary Science Letters 90, 297-314. Kamenetski V.S., Chung S.-L., Kamenetski M.B., Kuzmin D.V., 2012. Picrites from the Emeishan large igneous province, SW China: a compositional continuum in primitive magmas and their respective mantle sources. Journal of Petrology 53 (N10), 2095-2113. Kogiso T., Hirose K., Takahashi E., 1998. Melting experiments on homogeneous mixtures of peridotite and basalt: Application to the genesis of ocean island basalts. Earth and Planetary Science Letters 162, 45-61. Koloskov A.V., 1999. Ultrabasic inclusions and volcanics as a self-regulated geologic system. Nauchnyi Mir, Moscow (in Russian). Koloskov A.V., Fedorov P.I., Rashidov V.A., 2016. New data on products composition of the Quaternary volcanic activity in the shelf zone of NW margins of the South China Sea and the problem of asthenospheric diapirism. Koloskov A.V., Flerov G. B., Sharas’kin A. Y., 1989. Rift-Related Volcanism in the System of Eastern Asian Volcanic Belts. In Magmatism of Rifts: Petrology, Evolution, Geodynamics, Ed. by O. A. Bogatikov, Nauka, Moscow, 139-144 (in Russian). Koloskov A.V., Rashidov,V. A., Gatinskii Y. G., et al., 2003. Late Cenozoic volcanism in the continental shelf zones of Vietnam. In Proceedings of the Annual Conference Devoted to the Day of Volcanologists. Naukadlya Kamchatki, Petropavlovsk Kamchatskii, 9-15 (in Russian). Kudrass H. R., Hiedicke M., Cepek P., Kreuzer H., and Müller P., 1986. Mesozoic and Cenozoic rocks dredged from the South China Sea (Reed Bank area) and Sulu Sea and their significance for plate tectonic reconstructions. Mar. Pet. Geol.3, 19-30. Kushiro I., 1990. Partial melting of mantle wedge and evolution of island arc crust. Journal of Geophysical Research 95, 15929-15939. Kushiro I., 1996. Partial melting of a fertile mantle peridotite at high pressures: An experimental study using aggregates of diamond. In Basu A., and Hart S., eds. Earth processes: Reading the isotopic clock: American Geophysical Union Geophysical Monograph 95, 109-122. Kushiro I., 1998. Compositions of partial melts formed in mantle peridotites at high pressures and their relation to those of primitive MORB. Physics of the Earth and Planetary Interiors 107, 103-110. Latin D., White N., 1990. Generating melt during lithospheric extension: uniform vs. simple shear. Geology 18, 327-331. Le Bas M.J., Le Maitre R.W., Streckeisen A., Zanettin B., 1986. A chemical classification of volcanic rocks based on the total alkali-silica diagram. Journal of Petrology 27, 745-750. Le Duc Anh, Nguyen Hoang, 2017. Geochemistry of Cenozoic basalts in the south-Central Vietnam coastline region: implications for regional mantle - lithosphere interaction. Vietnam Journal of Earth Sciences, in preparation. Lee T.Y., Lo C-H., Chung S-L., Chen C-Y., Wang L., Lin W-P., Nguyen Hoang, Cung Thuong Chi, Nguyen Trong, Yem, 1998. 40Ar/39Ar dating result of Neogene basalts in Vietnam and its tectonic implication. In: Flower, M.F.J., et al. (Eds.), Mantle Dynamics and Plate Interactions in East Asia. Geodynamics Series, vol. 27, American Geophysics Union, 317-330. Li C.-F., et al., 2014. Ages and magnetic structures of the South China Sea constrained by deep tow magnetic surveys and IODP Expedition 349, Geochem. Geophys. Geosys., 15, 4958-4983. Li C-F., et al., 2015. Seismic stratigraphy of the central South China Sea basin and implications for neotectonics. J. Geophys. Res. Solid Earth, 120, 1377-1399. Doi:10.1002/2014JB011686. Li C.-F., Lin J., Kulhanek D.K., 2013. South China Sea tectonics: Opening of the South China Sea and its implications for southeast Asian tectonics, climates, and deep mantle processes since the late Mesozoic, IODP SCI. Prosp., 349. Li L., Clift P., Nguyen The Hung, 2013. The sedimentary, magmatic and tectonic evolution of the southwestern South China Sea revealed by seismic stratigraphic analysis. Marine Geophysical Research 34, 341-365. Li L., Clift P.D., Stephenson R., Nguyen T.H., 2014. Non-uniform hyper-extension in advance of seafloor spreading on the Vietnam continental margin and the SW South China Sea. Basin Research 26, 106-134. Malinovsky A.I., Rashidov V.A., 2015. Compositional characteristics of sedimentary and volcano-sedimentary rocks of Phu Quy-Catwickisland group in the continental shelf of Vietnam. Bulletin of Kamchatka Regional Association of ‘Educational - Scientific’ Center, Earth Sciences 27 (3), 12-34 (in Russian with English summary). McKenzie D., Bickle M.J., 1988. The volume and composition of melt generated by extension of the lithosphere. Journal of Petrology 26, 625-679. McKenzie D., O’Nions R.K., 1991. Partial melt distribution from inversion of rare earth element concentrations. Journal of Petrology 32, 1021-1091. Nguyen Hoang, 2005a. Source characteristics and melting conditions of Cenozoic basalts from Pleiku, south-central Vietnam. Journal of Geology Series A 286, 15-22 (in Vietnamese with English abstract). Nguyen Hoang, 2005b. Lithospheric mantle beneath Pleiku: evidence from mantle xenolith. Journal of Geology Series A 287, 8-19 (in Vietnamese with English abstract). Nguyen Hoang, Flower M.F.J., 1998. Petrogenesis of Cenozoic basalts from Vietnam: implication for origins of a diffuse igneous province. J. Petrol. 39, 369-395. Nguyen Hoang, Flower M.F.J., Carlson R.W., 1996. Major, trace element, and isotopic compositions of Vietnamese basalts: interaction of enriched mobile asthenosphere with the continental lithosphere? Geochimica et Cosmochimica Acta 60, 4329-4351. Nguyen Hoang, Uto K., 2003. Geochemistry of Cenozoic basalts in the Fukuoka district (northern Kyushu, Japan), implications for asthenosphere and lithospheric mantle interaction. Chemical Geology 198, 249-268. Nguyen Hoang, Phan Trong Trinh, 2009. Overview of petrologic and geochemical characteristics of Neogene-Quaternary basalts in the East Vietnam Sea and neighboring regions and their related mantle dynamics. Journal of Geology, 312A, 39-57 (in Vietnamese with English abstract). Nguyen Hoang, Flower M.F.J., Cung Thuong Chi, Pham Tich Xuan, Hoang Van Quy, Tran Thanh Son, 2013. Collision-induced basalt eruptions at Pleiku and Buon Me Thuot, south-central Viet Nam. Journal of Geodynamics 69, 65-83. Nguyen Hoang, Ogasawara M., Tran Thi Huong, Phan Van Hung, Nguyen Thi Thu, Cu Sy Thang, Pham Thanh Dang, Pham Tich Xuan, 2014. Geochemistry of Neogene basalts in the Nghia Dan district, western Nghe An. Vietnam Journal of Earth Sciences 36(4), 403-412. DOI: 10.15625/0866-7187/36/4/6428. Nguyen Hoang, Tran Thi Huong, Ogasawara M., Le Duc Anh, Nguyen Thi Mai, Nguyen Thi Thu, Cu Sy Thang, Le Thi Phuong Dung, 2016. Petrography and geochemistry of Permian basalts of the Cam Thuy formation and their relation to Song Da and Emeishan magmatic rocks. Vietnam Journal of Earth Sciences 38, 372-392. DOI: 10.15625/0866-7187/38/4/8993. Nguyen Nhu Trung, Lee S.M., Bui Cong Que, 2004. Satellite gravity anomalies and their correlation with the major tectonic features in the South China Sea. Gondwana Research 7(2), 407-424. Nguyen Nhu Trung, Nguyen Thi Thanh Huong, 2013. Topography of the Moho and Earth crust structure beneath the East Vietnam Sea from 3D inversion of granite field data. Acta Physica 61(2), 357-384. Norman M.D, Garcia M.O., 1999. Primitive magmas and source characteristics of the Hawaiian plume: petrology and geochemistry of shield picrites. Earth and Planetary Science Letters 168, 27-44. Pearce J.A., Norry M.J., 1979. Petrogenetic implications of Ti, Zr, Y, and Nb variations in volcanic rocks. Contributions to Mineralogy and Petrology 69, 33-47. Rangin C. Huchon, Le Pichon X., Bellon H., Lepvrier C., Roques D., Hoe N.D., Quynh V., 1995. Cenozoic deformation of central and south Vietnam. Tectonophysics 251, 179-196. Regelous M., Niu Y., Wendt J.I., Batiza R., Greig A., Collerson K.D., 1999. Variations in the geochemistry of magmatism on the East Pacific Rise at 10°30’N since 800 ka. Earth Planet. Sci. Lett. 168, 45-63. Roeder P.L., Emslie R.F., 1970. Olivine-liquid Equilibrium. Contributions to Mineralogy and Petrology 29, 275-289. Ru K., Pigott J.D., 1986. Episodic rifting and subsidence in the South China Sea. AAPG Bull 70(9), 1136-1155. Rudnik R.L., Fontaine D.M., 1995. Nature and composition of the continental crust: a lower crustal perspective. Review Geophysics, 33, 267-309. Sava D., Pubellier M., Franke D., Chamot-Rooke N., Meresse F., Steuer S., Auxietre J.L., 2014. Different expressions of rifting on the South China Sea margins. Marine and Petroleum Geology 58, 579-598. Scarrow, J. H., Cox, K. G., 1995. Basalts generated by decompressive adiabatic melting of a mantle plume: a case study from the Isle of Skye, NW Scotland. Journal of Petrology 36, 3-22. Sun S.S., McDonough W.F., 1989. Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. In: Saunders, A.D., Norry, M.J. Eds. Magmatism in Ocean Basins. Geol. Soc. Spec. Publ., London, 313-345. Takahashi E., Kushiro I., 1983. Melting of a dry peridotite at high pressures and basalt magma genesis. American Mineralogist 68(9-10), 859-879. Tamaki K., 1995. Upper mantle extrusion tectonics of southeast Asia and formation of western Pacific backarc basins. In: International Workshop: Cenozoic Evolution of the Indochina Peninsula, Hanoi/Do Son, April, p.89 (Abstract with Programs). Taylor S.R., McLennan S.M., 1985. The continental crust: Its composition and evolution.Blackwell Scientific Publishers, Oxford. Tran Duc Luong, Nguyen Xuan Bao, 1981. Geological map 1:500.000 of Vietnam. Tu K., Flower M.F.J., Carlson R.W., Zhang M., Xie G.-H., 1991. Sr, Nd, and Pb isotopic compositions of Hainan basalts (South China), implications for a subcontinental lithosphere DUPAL source. Geology 19(6), 567-569. Tu K., Flower M.F.J., Carlson R.W., Zhang M., Xie G.H., 1992. Magmatism in the South China Basin, 1.Isotopic and trace element evidence for an endogenous Dupal mantle component. Chemical Geology 97, 47-63. Turner S., Hawkesworth C., 1995. The nature of the sub-continental mantle: constraints from the major element composition of continental flood basalts. Chemical Geology 120, 295-314. Walker D., Shibata T., DeLong D.E., 1979. Abyssal tholeiites from the Oceanographer Fracture Zone III. Phase equilibria and mixing. Contributions to Mineralogy and Petrology 70, 111-125. Yamashita S., Tatsumi Y., Nohda S., 1996. Temporal variation in primary magma compositions in the northeast Japan Arc, The Island Arc5, 276-288. Yan Q., Shi X., Castillo R.B., 2014. The late Mesozoic-Cenozoic tectonic evolution of the South China Sea: A petrologic perspective. Journal of Asian Earth Sciences 85, 178-201. Yang Y., Liu M., 2009. Crustal thickening and lateral extrusion during the Indo-Asian collision: a 3D viscous flow model. Tectonophysics 465, 128-135. Zhou P., Mukasa S., 1997. Nd-Sr-Pb isotopic, and major- and trace-element geochemistry of Cenozoic lavas from the Khorat Plateau, Thailand, sources and petrogenesis. Chemical Geology 137, 175-193

    Morphological Filter Detector for Image Forensics Applications

    Get PDF
    Mathematical morphology provides a large set of powerful non-linear image operators, widely used for feature extraction, noise removal or image enhancement. Although morphological filters might be used to remove artifacts produced by image manipulations, both on binary and graylevel documents, little effort has been spent towards their forensic identification. In this paper we propose a non-trivial extension of a deterministic approach originally detecting erosion and dilation of binary images. The proposed approach operates on grayscale images and is robust to image compression and other typical attacks. When the image is attacked the method looses its deterministic nature and uses a properly trained SVM classifier, using the original detector as a feature extractor. Extensive tests demonstrate that the proposed method guarantees very high accuracy in filtering detection, providing 100% accuracy in discriminating the presence and the type of morphological filter in raw images of three different datasets. The achieved accuracy is also good after JPEG compression, equal or above 76.8% on all datasets for quality factors above 80. The proposed approach is also able to determine the adopted structuring element for moderate compression factors. Finally, it is robust against noise addition and it can distinguish morphological filter from other filters

    Geochemical features of Sakhalin Island mud volcanoes

    Get PDF
    The study, based on a complex geochemical research, found that the composition of the most chemical elements in mud breccia from the Yuzhno-Sakhalinsky (YSMV) and Pugachevsky (PMV) mud volcanoes (Sakhalin Island), the unique phenomena of endogenous defluidization in the Hokkaido-Sakhalin fold system (alpine-type folding), are comparable to Clark (C) contents of these elements (0.8-1.2 ×C). For Na, Li, Zn andSn, the ratio between the elemental contentsand their Clarke values (Csample/Clark value) vary from 1.4 to 5.2 xC. But the increased contents of Na and Li are due to the ascending endogenous fluid revealed. Study of the mud breccia chemical composition changes in different explosive activity of YSMV under the seismic activity variationsallowed to establish that, when the mud-volcanic gryphonsare activated against the background of increase in the temperature of the water-mud mixture and the emission of spontaneous gases, the contents of a number of elements (iron, calcium, manganese, rare earth elements, etc.) are decreased. This is explained by the formation of soluble hydrocarbonate complexes. Daginskiegasgeothermal system (DGHS) trace elements depletedooze samples were compared with YSMV and PMVsamples and exposedthat thehigh ratios of Csample /Clarke values for the majority of elements do not exceed 0.6 × C.Ooze samples from DGHS having higher elemental contents than Clark contents were observed only for Cd content (2.2-3.4 ×C) and Pb (0.7-1.5 ×C). Analysis of diatom flora on the DGHS site indicates the existence of an active fluid dynamic system that drains oil and gas bearing complexes. The factors determining the "weighting" of the methane carbon isotope composition in the southern part of Sakhalin Island are the increased seismic activity of deep-seated faults, as well as the presence of intrusions (diabase) and metamorphically altered rocks.References Aliyev A.A., Guliyev I.S., Rakhmanov R.R., 2009. Catalog of eruptions of Azerbaijan mud volcanoes (1810-2007). Baku Nafta-Press, 109p. Astakhov A.S., et al., 2002. Defluitization process dynamic of the Central Sakhalin fault at seismic activization (by monitoring results of the Yuzhno-Sakhalinsky mud volcano in July - August 2001) DAN 2002, 386(2), 223-228. Decisions of operational interdepartmental regional stratigraphical meetings on the Paleogene and Neogene of east regions of Russia-Kamchatka, Koryak Upland, Sakhalin and Kuril Islands, 1998. An explanatory note to stratigraphical schemes. Responsible editor Gladenkov Y.B. Moscow GEOS, 147p. Diatomic algae of the USSR (fossil and modern), 1974. Leningrad Nauka, 1(1), 404p. Dubinin A.V., 2006. Geochemistry of rare-earth elements in the ocean. Moscow Nauka, 360p. Ershov V.V., Shakirov R.B., Obzhirov A.I., 2011. Isotope and geochemical characteristics of the Yuzhno-Sakhalinsky mud volcano free gases and their connection with regional seismicity. DAN, 440(2), 256-261. Fedorov Y.N., et al., 2012. Crude oil microelement characteristic of Vogulkinsky and Tyumen basins oil and gas area: comparison. Lithosphere, 2, 141-151. Geology of the USSR, 33. Sakhalin Island/Under the edited by Sidorenko A.V. Moscow Nedra, 1970, 464p. Grigoriev N. A., 2008. About clark content of chemical elements in the top part of continental crust. Lithosphere 1, 61-71. Thesis: 11.00.00. Yuzhno-Sakhalinsk, IMGG FEB RAS, 244p. Hasle G.R., Syvertsen E.E., 1996. Marine diatoms. Identifying Marine Phytoplankton. San Diego, Academic Press, 5-385. Horita J., 2001. Carbon isotope exchange in the system CO2-CH4 at elevated temperatures. Geochimica et Cosmochimca Acta, 65, 1907-1919. Kholodov V.N., 2002. Mud volcanoes: distribution regularities and genesis. Lithology and Mineral Resources, 3, 227-22001.41. Kopf A.J., 2002. Significance of mud volcanism. Rev. Geophys, 40(2), 2-1-2-52. Liu Chia-Chuan, et al., 2013. The geochemical characteristics of the mud liquids in the Wushanting and Hsiaokunshui Mud Volcano region in southern Taiwan: Implications of humic substances for binding and mobilization of arsenic. Journal of Geochemical Exploration, 128, 62-71. Lobodenko I.Y., 2010. Holocenic tectonic deformations (paleoseismodislocations) in zones of the Hokkaido-Sakhalin and Central Sakhalin faults. Candidate of geological and mineralogical science thesis. Moscow, 22p. Melnikov O.A., 1987. Structure and geodynamics of the Hokkaido-Sakhalin folded region. Moscow Nauka, 93p. Melnikov O.A., 2011. About dynamics and nature of Pugachevsky group the gaswaterclastic ("mud") volcanoes on Sakhalin according to visual observations and an orohydrography. Volcanology and Seismology, 6, 47-59. Melnikov O.A., Ershov V.V., Kim Chong Un, etc., 2008.  About the mud spring activity dynamic of the gaswaterclastic ("mud") volcanoes and its connection with seismicity on the example of the Yuzhno-Sakhalinsky volcano (Sakhalin Island). Pacific Geology 27(5), 25-41. Melnikov O.A., Iliev A.Y., 1989. About new manifestations of mud volcanism on Sakhalin Island. Pacific geology 3, 42-48. Milkov, A.V., 2000. Worldwide distribution of submarine mud volcanoes and associated gas hydrates. Marine Geology 167, 29-42. Oreshkin V.N., Gordeev V.V., 1983. Geochemistry of cadmium and plumbum in suspension of the rivers of Black, Azov and Caspian Sea areas. Geochemistry, 4, 603-613. Petelin V.P., 1957. Mineralogy of sand-aleurite fractions in the Sea of Okhotsk marine sediments. Proceedings of Oceanology Institute of USSR Academy of Sciences, XXII. Prasolov E.M., 1990. Isotope geochemistry and origin of natural gases. St. Petersburg: Nedra, 283p. Shakirov R.B., 2016. Gasgeochemical fields of the marginal seas on the Far Eastern Region: distribution, origin, relations to the geological structures, gashydrates and seismo-tectonics. Dissertation of Doctor of Geological and Mineralogical Sciences (Dr.Sci.). POI FEB RAS, Vladivostok 459p. (In Russian). Shakirov R.B., Syrbu N.C., Obzhirov A.I., 2012. Isotope and gas-geochemical features of methane and carbon dioxide distribution on Sakhalin Island and adjacent shelf of the Okhotsk Sea. Bulletin of KRAESC Earth Sciences, 2(20), 100-113. Shnyukov E.V., et al., 1992. Mud volcanism of the Kerch and Tamansky region. Kiev, Naukova dumka, 200p. Siryk I.M., 1968. Oil and gas content of the east slopes of the West Sakhalin mountains. Moscow: Nauka, 8-14. Sorochinskaya A.V., et al., 2008. Geochemical and mineralogical features of mud volcanoes of Sakhalin Island. Bulletin of FEB RAS, 4, 58-65. Veselov О.V., Soinov V.V., 1997. Tektonosphere geodynamics of conjaction zone of the Pacific Ocean with Eurasia. Yuzhno Sakhalinsk: IMGG FEB RAS 4, 153-176. Veselov O.V., Volgin P.F., Lutaya L.M., 2012.  Structure of the Pugachevsky mud-volcano sedimentary cover (Sakhalin Island) by geophysical modeling data. Pacific Geology, 31(6), 4-15. Vinogradov A.P., 1962. Average contents of chemical elements in the main types the igneous rocks. Geochemistry, 7, 555-571. Yakubov A.A., et al., 1980. Mud volcanism of the Soviet Union and its connection with oil-and-gas content. Baku, 165p. Zharov A.E., Mitrofanova L.I., Tuzov V.P., 2013. Stratigraphy of Cainozoic sedoiments of the Northern Sakhalin shelf. Stratigraphy, Geological correlation 21(5), 72-93

    Plasmodium knowlesi malaria in Vietnam: some clarifications

    Get PDF
    A recently published comment on a report of Plasmodium knowlesi infections in Vietnam states that this may not accurately represent the situation in the study area because the PCR primers used may cross-hybridize with Plasmodium vivax. Nevertheless, P. knowlesi infections have been confirmed by sequencing. In addition, a neighbour-joining tree based on the 18S S-Type SSUrRNA gene shows that the Vietnamese samples clearly cluster with the P. knowlesi isolates identified in Malaysia and are distinct from the corresponding P. vivax sequences. All samples came from asymptomatic individuals who did not consult for fever during the months preceding or following the survey, indicating that asymptomatic P. knowlesi infections occur in this population, although this does not exclude the occurrence of symptomatic cases. Large-scale studies to determine the extent and the epidemiology of P. knowlesi malaria in Vietnam are further needed

    α-Synuclein interacts directly but reversibly with psychosine: implications for α-synucleinopathies

    Get PDF
    Aggregation of α-synuclein, the hallmark of α-synucleinopathies such as Parkinson´s disease, occurs in various glycosphingolipidoses. Although α-synuclein aggregation correlates with deficiencies in the lysosomal degradation of glycosphingolipids (GSL), the mechanism(s) involved in this aggregation remains unclear. We previously described the aggregation of α-synuclein in Krabbe´s disease (KD), a neurodegenerative glycosphingolipidosis caused by lysosomal deficiency of galactosyl-ceramidase (GALC) and the accumulation of the GSL psychosine. Here, we used a multi-pronged approach including genetic, biophysical and biochemical techniques to determine the pathogenic contribution, reversibility, and molecular mechanism of aggregation of α-synuclein in KD. While genetic knock-out of α-synuclein reduces, but does not completely prevent, neurological signs in a mouse model of KD, genetic correction of GALC deficiency completely prevents α-synuclein aggregation. We show that psychosine forms hydrophilic clusters and binds the C-terminus of α-synuclein through its amino group and sugar moiety, suggesting that psychosine promotes an open/aggregation-prone conformation of α-synuclein. Dopamine and carbidopa reverse the structural changes of psychosine by mediating a closed/aggregation-resistant conformation of α-synuclein. Our results underscore the therapeutic potential of lysosomal correction and small molecules to reduce neuronal burden in α-synucleinopathies, and provide a mechanistic understanding of α-synuclein aggregation in glycosphingolipidoses.Fil: Abdelkarim, Hazem. University of Illinois; Estados UnidosFil: Marshall, Michael S.. University of Illinois; Estados UnidosFil: Scesa, Giuseppe. University of Illinois; Estados UnidosFil: Smith, Rachael A.. University of Illinois; Estados UnidosFil: Rue, Emily. University of Illinois; Estados UnidosFil: Marshall, Jeffrey. University of Illinois; Estados UnidosFil: Elackattu, Vince. University Of Illinois Chicago; Estados UnidosFil: Stoskute, Monika. University Of Illinois Chicago; Estados UnidosFil: Issa, Yazan. University Of Illinois Chicago; Estados UnidosFil: Santos, Marta. University Of Illinois Chicago; Estados UnidosFil: Nguyen, Duc. University Of Illinois Chicago; Estados UnidosFil: Hauck, Zane. University Of Illinois Chicago; Estados UnidosFil: Van Breemen, Richard B.. University Of Illinois Chicago; Estados UnidosFil: Celej, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; ArgentinaFil: Gaponenko, Vadim. University Of Illinois Chicago; Estados UnidosFil: Bongarzone, Ernesto R.. University Of Illinois Chicago; Estados Unido

    inVestIgating the pSychologIcal and ecONomic impAct of cataRact surgerY in Vietnam: The VISIONARY observational study protocol

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Visual impairment caused by cataracts not only affects an individual's quality of life but can also have a profound impact on other important psychological factors and on the economic circumstances of individuals and their households. Cataract surgery is an effective intervention to restore vision and is also associated with other positive consequences including improvements in quality of life, economic and psychological outcomes. While there has been an increase in the number and quality of cataract surgeries performed in Vietnam, the programs currently in place are still unable to meet the existing demand and need for surgery. Data on both the cost-effectiveness of cataract surgery and the economic and psychological impact of untreated cataract in this setting is lacking.</p> <p>Methods/Design</p> <p>This study, investigating the psychological and economic impact of cataract surgery in Vietnam (VISIONARY), will recruit and interview a sample of adults (18 years or over) who are referred for cataract surgery by one of the following sites and their outreach programs: Hue Eye Hospital; Thai Binh Eye Hospital; Binh Dinh Department of Health Eye Hospital and the Vinh Long Department of Health Social Disease Centre. All participants (those who have cataract surgery and those who do not have surgery) will be followed up at six and 12 months.</p> <p>Discussion</p> <p>This study is designed to examine the impact of low vision on household economic circumstances and psychological outcomes as well as to investigate the effectiveness and cost-effectiveness of cataract surgery in Vietnam. It will help to inform international and national non-government organisations working in the country and local policy-makers on priorities for further investment in eye-health services in this setting and their relevance to broader economic development goals.</p
    corecore