955 resultados para Heating from central stations
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The measurements were obtained during two North Sea wide STAR-shaped cruises during summer 1986 and winter 1987, which were performed to investigate the circulation induced transport and biologically induced pollutant transfer within the interdisciplinary research in the project "ZISCH - Zirkulation und Schadstoffumsatz in der Nordsee / Circulation and Contaminant Fluxes in the North Sea (1984-1989)". The inventory presents parameters measured on hydrodynamics, nutrient dynamics, ecosystem dynamics and pollutant dynamics in the pelagic and benthic realm. The research program had the objective of quantifying fluxes of major budgets, especially contaminants in the North Sea. In spring 1986, following the phytoplankton spring bloom, and in late winter 1987, at minimum primary production activity, the North Sea ecosystem was investigated on a station net covering the whole North Sea. The station net was shaped like a star. Sampling started in the centre, followed by the northwest section and moving counter clockwise around the North Sea following the residual currents. By this strategy, a time series was measured in the central North Sea and more synoptic data sets were obtained in the individual sections. Generally advection processes have to be considered when comparing the data from different stations. The entire sampling period lasted for more than six weeks in each cruise. Thus, a time-lag should be considered especially when comparing the data from the eastern and the western part of the central and northern North Sea, where samples were taken at the beginning and at the end of the campaign. The ZISCH investigations represented a qualitatively and quantitatively new approach to North Sea research in several respects. (1) The first simultaneous blanket coverage of all important biological, chemical and physical parameters in the entire North Sea ecosystem; (2) the first simultaneous measurements of major contaminants (metals and organohaline compounds) in the different ecosystem compartments; (3) simultaneous determinations of atmospheric inputs of momentum, energy and matter as important ecosystem boundary conditions; (4) performance of the complex measurement program during two seasons, namely the spring plankton bloom and the subsequent winter period of minimal biological activity; and (5) support of data analysis and interpretation by oceanographic and meteorological numerical models on the same scales.
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Apatite fission track (FT) ages and length characteristics of samples obtained from Cambrian to Paleocene-aged sandstones collected along the margin of Nares Strait in Ellesmere Island in the Canadian Arctic Archipelago are dominated by a thermal history related to Paleogene relative plate movements between Greenland and Ellesmere Island. A preliminary inverse FT thermal model for a Cambrian (Archer Fiord Formation) sandstone in the hanging wall of the Rawlings Bay thrust at Cape Lawrence is consistent with Paleocene exhumational cooling, likely as a result of erosion of the thrust. This suggests that thrusting at Cape Lawrence occurred prior to the onset of Eocene compression, likely due to transpression during earlier strikeslip along the strait. Models for samples from volcaniclastic sandstones of the Late Paleocene Pavy Formation (from Cape Back and near Pavy River), and a sandstone from the Late Paleocene Mount Lawson Formation (at Split Lake, near Makinson Inlet) are also consistent with minor burial heating following known periods of basaltic volcanism in Baffin Bay and Davis Strait (c. 61-59 Ma), or related tholeiitic volcanism and intrusive activity (c. 55-54 Ma). Thermal models for samples from sea level dykes from around Smith Sound suggest a period of Late Cretaceous - Paleocene heating prior to final cooling during Paleocene time. These model results imply that Paleocene tectonic movements along Nares Strait were significant, and provide limited support for the former existence of the Wegener Fault. Apatite FT data from central Ellesmere Island suggest however, that cooling there occurred during Early Eocene time (c. 50 Ma), which was likely a result of erosion of thrusts during Eurekan compression. This diachronous cooling suggests that Eurekan deformation was partitioned at discrete intervals across Ellesmere Island, and thus it is likely that displacements along the strait were much less than the 150 km that has been previously suggested for the Wegener Fault.
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The modern Indian Ocean summer monsoon is driven by differential heating between the Asian continent and the Indian Ocean to the south. This differential heating produces a strong pressure gradient which drives southwest monsoon winds during June, July, and August. Satellite and meteorological observations, aerosol measurements, sediment trap studies, and mineralogical studies indicate an atmospheric mode of transport for modern lithogenic sediments in the northwest Arabian Sea. Analyses of lithogenic grain size and mass accumulation rate (MAR) records from the Owen Ridge indicate that eolian transport has been the primary mode of transport for the past 370 kyr. Visual inspection shows that the MAR record is positively correlated with global ice volume as indicated by the marine delta18O record. In contrast, the grain-size record varies at a much higher frequency, showing little correlation to either the MAR or the delta18O records. Spectral analyses confirm these relationships, indicating that the lithogenic grain-size and MAR records are coherent only over the precession band whereby the grain size leads the MAR by 124° (~8 kyr). We conclude that an eolian transport mechanism is the only mechanism that allows for this phase difference and at the same time is supported by comparison of the grain size and MAR with independent eolian records. We use lithogenic grain size as a paleoclimatic indicator of summer monsoon wind strength and lithogenic MAR as a paleoclimatic indicator of source-area aridity. These interpretations are supported by comparison of the lithogenic records to independent indicators of wind strength (Globigerina bulloides upwelling record) and aridity (a loess record from central China). Such comparisons indicate high coherence and zero phase relationships. Our work supports the findings of previous studies which have documented the link between monsoon strength and the Earth's axial precession cycles. Both the lithogenic MAR and the grain-size records have high coherency with precessional insolation. Maximum lithogenic MAR (source-area aridity) is in phase with delta18O (global ice volume) and leads maximum precessional insolation by 88° (~6 kyr). We attribute this lead to the influence of glacial conditions on the aridity, and therefore the deflation potential, of the source areas. Maximum lithogenic grain size (summer monsoon wind strength) lags maximum precession by 148° (~9 kyr). We attribute this lag both to the influence of global and/or local ice volume and to the availability of latent heat from the southern hemisphere Indian Ocean, the two of which combine to determine the strength of the Indian Ocean monsoon.
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Continuous measurements of ice crystal size have been carried out on an 80 m sequence between 2790 and 2870 m depth in the GRIP ice core from Central Greenland. The ice in this interval is at present considered to orginate from the Eemian interglacial period. The record reveals that the crystal size in ice older than 100,000 yr is highly dependent on climatic conditions at the time of snowfall. This dependence shows up as a strong correlation between ?18O values and crystal size throughout the Eemian, as well as a negative correlation between crystal size and several soluble and insoluble impurities. Although high-resolution impurity records are available from selected parts of the Eemian ice, the study is not conclusive on which impurities are most effective in slowing grain growth. It is shown that the normal grain-growth process, commonly observed in the upper few hundred metres of polar ice sheets, does not yield grain sizes compatible with observed ones at this depth in the ice sheet, even in those parts of the Eemian ice where impurity drag effects are not present. Polygonization of crystals within the ice sheet and the nucleation and rapid growth of new grains at relatively high temperatures in the lowest part probably play an important role in producing the observed grain-size variations. The relevance of possible flow disturbances of the GRIP Eemian climatic record for the results presented is discussed briefly.
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Planktic foraminifers Neogloboquadrina pachyderma (sin.) from 87 eastern and central Arctic Ocean surface sediment samples were analyzed for stable oxygen and carbon isotope composition. Additional results from 52 stations were taken from the literature. The lateral distribution of delta18O (18O/16O) values in the Arctic Ocean reveals a pattern of roughly parallel, W-E stretching zones in the Eurasian Basin, each ~0.5 per mil wide on the delta18O scale. The low horizontal and vertical temperature variability in the Arctic halocline waters (0-100 m) suggests only little influence of temperature on the oxygen isotope distribution of N. pachyderma (sin.). The zone of maximum delta18O values of up to 3.8 per mil is situated in the southern Nansen Basin and relates to the tongue of saline (> 33%.) Atlantic waters entering the Arctic Ocean through the Fram Strait. delta18O values decrease both to the Barents Shelf and to the North Pole, in accordance with the decreasing salinities of the halocline waters. In the Nansen Basin, a strong N-S delta18O gradient is in contrast with a relatively low salinity change and suggests contributions from different freshwater sources, i.e. salinity reduction from sea ice meltwater in the south and from light isotope waters (meteoric precipitation and river-runoff) in the northern part of the basin. North of the Gakkel Ridge, delta18O and salinity gradients are in good accordance and suggest less influence of sea ice melting processes. The delta13C (13C/12C) values of N. pachyderma (sin.) from Arctic Ocean surface sediment samples are generally high (0.75-0.95 per mil). Lower values in the southern Eurasian Basin appear to be related to the intrusion of Atlantic waters. The high delta13C values are evidence for well ventilated surface waters. Because the perennial Arctic sea ice cover largely prevents atmosphere-ocean gas exchange, ventilation on the seasonally open shelves must be of major importance. Lack of delta13C gradients along the main routes of the ice drift from the Siberian shelves to the Fram Strait suggests that primary production (i.e. CO2 consumption) does probably not change the CO2 budget of the Arctic Ocean significantly.
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The MAREDAT atlas covers 11 types of plankton, ranging in size from bacteria to jellyfish. Together, these plankton groups determine the health and productivity of the global ocean and play a vital role in the global carbon cycle. Working within a uniform and consistent spatial and depth grid (map) of the global ocean, the researchers compiled thousands and tens of thousands of data points to identify regions of plankton abundance and scarcity as well as areas of data abundance and scarcity. At many of the grid points, the MAREDAT team accomplished the difficult conversion from abundance (numbers of organisms) to biomass (carbon mass of organisms). The MAREDAT atlas provides an unprecedented global data set for ecological and biochemical analysis and modeling as well as a clear mandate for compiling additional existing data and for focusing future data gathering efforts on key groups in key areas of the ocean. The present data set presents depth integrated values of diazotrophs nitrogen fixation rates, computed from a collection of source data sets.
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The East Indies triangle, bordered by the Phillipines, Malay Peninsula and New Guinea, has a high level of tropical marine species biodiversity. Pristipomoides multidens is a large, long-lived, fecund snapper species that is distributed throughout the East Indies and Indo-Pacific. Samples were analysed from central and eastern Indonesia and northern Australia to test for genetic discontinuities in population structure. Fish (n = 377) were collected from the Indonesian islands of Bali, Sumbawa, Flores, West Timor, Tanimbar and Tual along with 131 fish from two northern Australian locations (Arafura and Timor Seas) from a previous study. Genetic variation in the control region of the mitochondrial genome was assayed using restriction fragment length polymorphism and direct sequencing. Haplotype diversity was high (0.67-0.82), as was intraspecific sequence divergence (range 0-5.8%). FST between pairs of populations ranged from 0 to 0.2753. Genetic subdivision was apparent on a small spatial scale; FST was 0.16 over 191 km (Bali/Sumbawa) and 0.17 over 491 km (Bali/Flores). Constraints to dispersal that contribute to, and maintain, the observed degree of genetic subdivision are experienced presumably by all life history stages of this tropical marine finfish. The constraints may include (1) little or no movement of eggs or larvae, (2) little or no home range or migratory movement of adults and (3) loss of larval cohorts due to transport of larvae away from suitable habitat by prevailing currents
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Six new smut fungi, Sporisorium rarum (type on Eulalia aurea), S. vermiculum (type on Sarga plumosa), S. xerofasciculatum (type on Xerochloa laniflora), Tilletia xerochloae (type on Xerochloa laniflora), T. yakirrae (type on Yakirra majuscula) and Ustilago lunata (type on Triodia longiceps), are described and illustrated from central and western Australia. Keys are provided for the smut fungi on Sarga and Xerochloa.
A combination of local inflammation and central memory T cells potentiates immunotherapy in the skin
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Adoptive T cell therapy uses the specificity of the adaptive immune system to target cancer and virally infected cells. Yet the mechanism and means by which to enhance T cell function are incompletely described, especially in the skin. In this study, we use a murine model of immunotherapy to optimize cell-mediated immunity in the skin. We show that in vitro - derived central but not effector memory-like T cells bring about rapid regression of skin-expressing cognate Ag as a transgene in keratinocytes. Local inflammation induced by the TLR7 receptor agonist imiquimod subtly yet reproducibly decreases time to skin graft rejection elicited by central but not effector memory T cells in an immunodeficient mouse model. Local CCL4, a chemokine liberated by TLR7 agonism, similarly enhances central memory T cell function. In this model, IL-2 facilitates the development in vivo of effector function from central memory but not effector memory T cells. In a model of T cell tolerogenesis, we further show that adoptively transferred central but not effector memory T cells can give rise to successful cutaneous immunity, which is dependent on a local inflammatory cue in the target tissue at the time of adoptive T cell transfer. Thus, adoptive T cell therapy efficacy can be enhanced if CD8+ T cells with a central memory T cell phenotype are transferred, and IL-2 is present with contemporaneous local inflammation. Copyright © 2012 by The American Association of Immunologists, Inc.
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The ALICE experiment is shown to be well suited for studies of exclusive final states from central diffractive reactions. The gluon-rich environment ofthe central system allows detailed QCD studies and searches for exotic mesonstates, such as glueballs, hybrids and new charmonium-like states. It wouldalso provide a good testing ground for detailed studies of heavy quarkonia. Dueto its central barrel performance, ALICE can accurately measure the low-masscentral systems with good purity. The efficiency of the Forward MultiplicityDetector (FMD) and the Forward Shower Counter (FSC) system for detectingrapidity gaps is shown to be adequate for the proposed studies. With thisdetector arrangement, valuable new data can be obtained by tagging centraldiffractive processes.
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We report for the first time Recent ostracods and bivalves from Central Tethys Himalaya, collected from Changru village, which is situated in the Tinker valley of northwestern Nepal near the Indo-Nepal border. The specimens were collected from the surface sediments of a small pond, shaped by a small tributary of the glacier fed Tinker River. The ostracod species belonging to the families Ilyocyprididae, Cyprididae and Candonidae and one bivalve (Pisidium sp., Family Pisidiidae) have been identified. Psychrodromus olivaccus and Potamocypris villosa are being reported for the first time from India and Nepal. Several broken and unidentifiable gyrogonites of charophyta were also recovered. The ostracod sample, as a whole, points to a shallow freshwater lake environment influenced by slowly running carbonate rich waters under cool temperatures, low mineralization and sparse vegetation. This is in accordance with the occurrence of Pisidium, which is commonly associated with ostracods in the freshwater lakes and streams. The ostracod fauna shows affinity with the fossil and extant forms recovered from the Higher and Tethys Himalaya of NW India. This opens a new opportunity for studying ostracods in the Indian Central Himalaya - a region which otherwise has been ignored until now.
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As a component of a three-year cooperative effort of the Washington State Department of Ecology and the National Oceanic and Atmospheric Administration, surficial sediment samples from 100 locations in southern Puget Sound were collected in 1999 to determine their relative quality based on measures of toxicity, chemical contamination, and benthic infaunal assemblage structure. The survey encompassed an area of approximately 858 km2, ranging from East and Colvos Passages south to Oakland Bay, and including Hood Canal. Toxic responses were most severe in some of the industrialized waterways of Tacoma’s Commencement Bay. Other industrialized harbors in which sediments induced toxic responses on smaller scales included the Port of Olympia, Oakland Bay at Shelton, Gig Harbor, Port Ludlow, and Port Gamble. Based on the methods selected for this survey, the spatial extent of toxicity for the southern Puget Sound survey area was 0% of the total survey area for amphipod survival, 5.7% for urchin fertilization, 0.2% for microbial bioluminescence, and 5- 38% with the cytochrome P450 HRGS assay. Measurements of trace metals, PAHs, PCBs, chlorinated pesticides, other organic chemicals, and other characteristics of the sediments, indicated that 20 of the 100 samples collected had one or more chemical concentrations that exceeded applicable, effects-based sediment guidelines and/or Washington State standards. Chemical contamination was highest in eight samples collected in or near the industrialized waterways of Commencement Bay. Samples from the Thea Foss and Middle Waterways were primarily contaminated with a mixture of PAHs and trace metals, whereas those from Hylebos Waterway were contaminated with chlorinated organic hydrocarbons. The remaining 12 samples with elevated chemical concentrations primarily had high levels of other chemicals, including bis(2-ethylhexyl) phthalate, benzoic acid, benzyl alcohol, and phenol. The characteristics of benthic infaunal assemblages in south Puget Sound differed considerably among locations and habitat types throughout the study area. In general, many of the small embayments and inlets throughout the study area had infaunal assemblages with relatively low total abundance, taxa richness, evenness, and dominance values, although total abundance values were very high in some cases, typically due to high abundance of one organism such as the polychaete Aphelochaeta sp. N1. The majority of the samples collected from passages, outer embayments, and larger bodies of water tended to have infaunal assemblages with higher total abundance, taxa richness, evenness, and dominance values. Two samples collected in the Port of Olympia near a superfund cleanup site had no living organisms in them. A weight-of-evidence approach used to simultaneously examine all three “sediment quality triad” parameters, identified 11 stations (representing 4.4 km2, 0.5% of the total study area) with sediment toxicity, chemical contamination, and altered benthos (i.e., degraded sediment quality), 36 stations (493.5 km2, 57.5% total study area) with no toxicity or chemical contamination (i.e., high sediment quality), 35 stations (274.1 km2, 32.0% total study area) with one impaired sediment triad parameter (i.e., intermediate/high sediment quality), and 18 stations (85.7km2, 10.0% total study area) with two impaired sediment parameters (i.e., intermediate/degraded quality sediments). Generally, upon comparison, the number of stations with degraded sediments based upon the sediment quality triad of data was slightly greater in the central Puget Sound than in the northern and southern Puget Sound study areas, with the percent of the total study area degraded in each region decreasing from central to north to south (2.8, 1.3 and 0.5%, respectively). Overall, the sediments collected in Puget Sound during the combined 1997-1999 surveys were among the least contaminated relative to other marine bays and estuaries studied by NOAA using equivalent methods. (PDF contains 351 pages)
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Common carp is one of the most important cultured freshwater fish species in the world. Its production in freshwater areas is the second largest in Europe after rainbow trout. Common carp production in Europe was 146,845 t in 2004 (FAO Fishstat Plus 2006). Common carp production is concentrated mainly in Central and Eastern Europe. In Hungary, common carp has been traditionally cultured in earthen ponds since the late 19th century, following the sharp drop in catches from natural waters, due to the regulation of main river systems. Different production technologies and unintentional selection methods resulted in a wide variety of this species. Just before the intensification of rearing technology and the exchange of stocking materials among fish farms (early sixties), “landraces” of carp were collected from practically all Hungarian fish farms into a live gene bank at the Research Institute for Fisheries, Aquaculture and Irrigation (HAKI) at Szarvas (Bakos and Gorda 1995; Bakos and Gorda 2001). In order to provide highly productive hybrids for production purposes starting from 1964, different strains and crosses between Hungarian landraces were created and tested. During the last 40 years, approximately 150 two-, three-, and four-line hybrids were produced. While developing parental lines, methods of individual selection, inbreeding, backcrossing of lines, gynogenesis and sex reversal were used. This breeding program resulted in three outstanding hybrids: “Szarvas 215 mirror” and “Szarvas P31 scaly” for pond production, and “Szarvas P34 scaly” for angling waters. Besides satisfying the needs of industry, the live gene bank helped to conserve the biological diversity of Hungarian carp landraces. Fifteen Hungarian carp landraces are still maintained today in the gene bank. Through exchange programs fifteen foreign carp strains were added to the collection from Central and Eastern Europe, as well as Southeast Asia (Bakos and Gorda 2001). Besides developing the methodology to maintain live specimens in the gene bank, the National Carp Breeding Program has been initiated in cooperation with all the key stakeholders in Hungary, namely the National Association of Fish Producers (HOSZ), the National Institute for Agricultural Quality Control (OMMI), and the Research Institute for Fisheries, Aquaculture and Irrigation (HAKI). In addition, methodologies or technologies for broodstock management and carp performance testing have been developed. This National Carp Breeding Program is being implemented successfully since the mid-1990s.
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ENGLISH: One phase of the duties of the Inter-American Tropical Tuna Commission is the gathering and interpretation of data concerning the life history of the commercially important bait species throughout the Eastern Pacific Ocean. During 1958 the Commission established a laboratory in Manta, Ecuador to study tuna. It was subsequently found that this fishery was dependent upon one species of anchovy, Anchoa naso, which was locally referred to as "colorado." During the calendar year 1959 approximately 380,000 scoops of bait were taken by the Manta tuna fleet (Schaefer, 1960), which at that time numbered about 23 vessels. Since then the fleet has increased by about 25 per cent and it is probable that the bait catch has increased also. Virtually nothing has been reported concerning the life history of this species. Hildebrand (1943) reviewed its taxonomy and reported standard lengths ranging from 32 to 135 mm. Peterson (1956) examined specimens from Central America and found them to range from 27 to 66 mm. He also indicated that the species spawned over a long period of time. The present report describes some aspects of the life history of Anchoa naso in Ecuadorian waters. The findings are based on 121 collections taken during the period March 1959 through June 1961. SPANISH: Una fase de las obligaciones de La Comisión Interamericana del Atún Tropical es la obtensión e interpretación de los datos concernientes a la historia natural de las especies de carnada comercialmente importantes en todo el Océano Pacifico Oriental. En el año de 1958 la Comisión estableció un laboratorio en Manta, Ecuador, para estudiar el atún. Se encontró subsecuentemente que esta pesquería dependía de una especie de anchoa, Anchoa naso, conocida localmente con el nombre de colorado. Durante el año calendario de 1959, la flota atunera de Manta, que en ese tiempo alcanzaba a unos 23 barcos, obtuvo aproximadamente 380,000 copas (scoops) de carnada (Schaefer, 1960). Desde entonces la flota ha aumentado en un 25 por ciento, y es probable que la captura de peces-cebo haya aumentado también. Nada se ha informado virtualmente sobre la historia natural de esta especie. Hildebrand (1943) revisó su taxonomia e informó sobre su longitud estándar, que varia entre los 32 y 135 mm. Peterson (1956) examinó especímenes de la América Central, y encontró que variaban entre los 27 y 66 mm. También indicó que la especie desova durante un largo periodo de tiempo. El presente informe describe algunos aspectos de la historia natural de la Anchoa naso en aguas ecuatorianas. Los hallazgos están basados en 121 recolecciones hechas durante el periodo de marzo de 1959 a junio de 1961. (PDF contains 30 pages.)
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In this report, accurate data from coastal stations and from the Vridi hydrological station were gathered. The used experiments took place from 1989 to 1991.