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Sample records for llanos centrales venezolanos

  1. Mesoproterozoic High-Pressure Metamorphism in the Llano Uplift, Central Texas, USA

    NASA Astrophysics Data System (ADS)

    Carlson, W. D.

    2009-05-01

    High-pressure (HP) terranes of Precambrian age are rare, and their rarity may reflect secular changes in the nature of subduction-zone processes. The Llano Uplift of central Texas contains evidence of HP metamorphism that dates back to the late Mesoproterozoic, documenting subduction and exhumation of the southern margin of the Laurentian continent. Collisional orogenesis in the Llano Uplift has been dated at ca. 1147-1116 Ma by U-Pb (zrc, ttn, mnz, rut) and Lu-Hf (grt-rut) geochronometry. This orogenic event drove metamorphism comprising both an initial high- pressure (HP) phase (610-775 C at 1.4-2.4 GPa) and a subsequent moderate-pressure (MP) phase (ca. 700 C at ~0.7 GPa). A low-pressure overprint (525-625 C at 0.3 GPa) took place under largely static conditions at ca. 1093-1070 Ma. Evidence for HP metamorphism is geographically widespread, but confined principally to boudins of mafic eclogite encased in felsic gneisses. The geographic distribution of P-T conditions for HP metamorphism inferred from the eclogites, combined with evidence from the relative degrees of homogenization of growth zoning in garnet, suggests a general increase from northeast to southwest in depths of burial during HP metamorphism. Exhumation of HP rocks to shallower depths prior to MP metamorphism appears to have been rapid: ages for the two phases of metamorphism overlap, on the basis of the very limited data now available. The region's early tectonometamorphic history shares numerous characteristics with well-documented examples of Phanerozoic continental-margin subduction, including: the presence of disrupted ophiolites; a paucity of coeval island-arc volcanics and plutonics; the involvement of precursors representing continental basement and supracrustal rocks; rapid exhumation to lower crustal levels with significant Barrovian-style overprinting; the preservation of the highest pressure record only in eclogitic pods and lenses within quartzofeldspathic gneisses; and the presence of

  2. Rb-Sr dating of Paleozoic glauconite from the Llano region, central Texas

    NASA Astrophysics Data System (ADS)

    Morton, John P.; Long, Leon E.

    1980-05-01

    Glauconite from eight stratigraphic horizons (Cambrian to Pennsylvanian) in the Llano Uplift, central Texas and two Cretaceous glauconites were analyzed by the Rb-Sr method. Only two untreated samples provide ages in agreement with those anticipated from current best estimates of the geologic time scale. With one exception all the other apparent ages fall short of the estimated age of deposition by as much as 22%. Low ages, the pattern customarily observed, are attributed to postdepositional loss of radiogenic 87Sr from expandable layers by weathering or during diagenesis. Detailed leaching experiments using a variety of reagents were performed to characterize the behavior of glauconite. The most promising treatment, which we recommend as standard procedure in all future studies, is with ammonium acetate which is able to purge the mineral of loosely-bound Rb and Sr while leaving tightly-bound components intact. After appropriate leach, three other Rb-Sr ages were brought into coincidence with their estimated ages of deposition. In contrast an Upper Cambrian glauconite was found to be extremely resistant to further alteration by chemical attack', providing an age of 429 ± 17 M yr. Although 17% short of the age of deposition, this age is interpreted as the time of a real event: diagenetic recrystallization induced by burial. Comparison of data from four samples indicates that for Paleozoic glauconite, conditions exist in which the Rb-Sr system is less susceptible to mild disturbance than is the K-Ar system.

  3. Recently discovered overthrusting northeast of Llano uplift along extension of San Marcos platform: new exploration frontier in central Texas

    SciTech Connect

    McMurdie, D.S.; Bryan, J.G.; Gibson, M.; King, T.; Sill, W.

    1986-05-01

    TJB Resources recently completed gravity, magnetotelluric, and seismic geophysical surveys in San Saba and Mills Counties north of the Llano uplift, west of the Ouachita Disturbed belt. Significant results show overthrusting has occurred 60-70 mi west of the Ouachita Disturbed belt. Earliest thrusting could have occurred in the Silurian-Devonian from south or southeast. Faulting reoccurs during Pennsylvanian Ouachita thrusting and again in the Late Cretaceous. The primitive Llano uplift buttressed the allochthonous rocks moving north and west. Magnetotelluric and gravity data indicate the Llano uplift is a separate and distinct isolated remnant or terrain, with numerous igneous intrusions reaching to great depths. Associated with this thrusting is a major tectonic northwest-southeast lineament located parallel to the termination of the Cretaceous rocks, outcropping on the western edge of Mills and Lampasas Counties. This lineament is documented by east-west seismic lines displaying a 0.3-sec displacement and farther southwest a 1.1-sec displacement. Paleozoic fossils were found near the surface trace of the northwest-southwest lineament as observed on the east-west seismic line. This area was previously mapped as Cretaceous. Surface inspection found Paleozoic rocks containing crinoids, spirifers, and rugose corals, with beds dipping to 45/sup 0/, contrasted with the N2/sup 0/ regional dip surrounding the lineament area. Well-log correlations from Marble Falls to Ellenberger range from 350 to 600 ft from east to west near the Llano uplift. The 60 to 70-mi frontal edge of the thrusting provides potential hydrocarbon traps along a north to northeast trend from central Texas to Oklahoma.

  4. Petrogenesis of Mesoproterozoic granitic plutons, eastern Llano Uplift, central Texas, USA

    NASA Astrophysics Data System (ADS)

    Smith, R. K.; Gray, Walt; Gibbs, Tyson; Gallegos, M. A.

    2010-08-01

    The Llano Uplift of central Texas is a gentle structural dome exposing ˜ 1370 to 1230 Ma metaigneous and metasedimentary rocks of Grenville affinity along the southern margin of Laurentia. The metamorphic rocks were subsequently intruded by ˜ 1119 to 1070 Ma late syn- to post-tectonic granites collectively known as the Town Mountain Granite (TMG). The eastern most of the TMG, the Marble Falls (MF), Kingsland (KL), and Lone Grove (LG) plutons, are metaluminous to marginally peraluminous, high-K, calc-alkaline, ferroan, biotite-calcic amphibole granites [Fe/(Fe + Mg) = 0.71-0.92 and 0.78-0.91 for biotite and calcic amphibole, respectively] displaying distinct variation trends with increasing silica content. They are chemically and texturally zoned and have mineralogical and chemical characteristics similar to A-type granites; i.e., 1) Fe-rich biotites, calcic amphiboles, accessory fluorite, and sporadic rapakivi texture, 2) high K 2O (> 4 wt.%), 3) low Al 2O 3 (< 16 wt.%) and CaO (< 3 wt.%), 4) high Fe/(Fe + Mg), 5) enrichments in Zr, Nb, REE, Ga/Al, and 6) depleted Eu. However, in contrast to typical A-type granites (having low Sr and Ba) the MF, KL,and LG plutons are enriched in Sr and Ba; i.e., up to 229 ppm and 1090 ppm, respectively. On granite discrimination diagrams [(K 2O + Na 2O)/CaO vs. Zr + Nb + Ce + Y (ppm) and Zr (ppm) vs. Ga/Al*10,000] the KL and MF plutons plot within the A-type field, whereas the LG pluton compositions are divided between A-type and fractionated granite fields (I-, S- and M-types). On tectonic discrimination diagrams (Y vs. Nb ) the MF and KL granites plot in the "within-plate" granite field, but the LG pluton plots across several fields including "within-plate" and "volcanic arc plus syn-collisional" fields. Consequently the tectonic classification on a geochemical basis for the LG pluton is unclear. Based on thermal metamorphic mineral assemblages, normative Q-Ab-Or plots, and Q-Ab-Or-H 2O experimental data (Johannes and Holtz

  5. Mesoproterozoic plate tectonics: A collisional model for the Grenville-aged orogenic belt in the Llano uplift, central Texas

    NASA Astrophysics Data System (ADS)

    Mosher, S.; Levine, J. S. F.; Carlson, W. D.

    2008-01-01

    The Llano uplift of central Texas, United States, exposes thecore of a Mesoproterozoic orogenic belt that formed along thesouthern margin of Laurentia during Grenville time. A new collisionalmodel is proposed that reconciles differences in structuralstacking, apparent tectonic transport, and deformation conditionsbetween the eastern and western portions of the uplift and explainsuplift and exhumation of high-pressure eclogitic rocks, emplacementof ophiolitic rocks, and subsequent late-stage to postcollisionalplutonism. Our model proposes that subduction with southwardpolarity resulted in collision of an exotic arc with Laurentia,emplacement of ophiolitic rocks, and telescoping of the interveningbasinal sediments, followed by overriding of the arc and marginof Laurentia by a southern continent with transport toward Laurentia.The model further proposes that convergence led to subductionof the Laurentian margin, resulting in high-pressure metamorphism,but buoyancy forces due to subduction of continental crust underthe southern continent resulted in uplift and retrotransportaway from Laurentia, in a manner similar to that proposed forthe Alpine orogeny. Slab breakoff resulted in upwelling of theasthenosphere, leading to intrusion of juvenile granitic plutons.Subduction along strike caused continued contraction that wanedwith time. The eastern uplift records continent-arc-continentcollision, whereas the western uplift records continent-continentcollision; the two regions also expose different crustal levelsin the orogen. The striking similarity with Phanerozoic orogens,including emplacement of ophiolites and formation of high-pressurerocks, implies that plate tectonic processes including subductionwere active prior to the Neoproterozoic.

  6. Characterization and tectonic evolution of a Mesoproterozoic island arc in the southern Grenville Orogen, Llano uplift, central Texas

    NASA Astrophysics Data System (ADS)

    Roback, Robert C.

    1996-11-01

    Integrated field and U-Pb geochronologic data document the presence and tectonic evolution of a distinct lithotectonic terrane in the southeastern Llano uplift, here termed the Coal Creek Domain (CCD). The CCD consists of tonalitic and amphibolitic gneisses, foliated gabbroic, tonalitic, and granodioritic intrusions, and the structurally emplaced Coal Creek Serpentinite. The oldest rocks in the CCD consist of tonalitic gneisses with protolith crystallization ages of 1326 Ma and 1301 Ma and pre-1292 Ma amphibolitic gneisses (all ages are U-Pb zircon). They were intruded by dominantly mafic and intermediate with subordinate amounts of felsic low-K plutonic rocks between 1286 Ma and 1275 Ma. High-temperature metamorphism and local anatexis that resulted in the formation of gneisses and migmatites occurred between 1301 Ma and 1286 Ma and is suggested to have occurred at ˜1292 Ma. Metamorphism at 1256 Ma resulted in the growth of zircons in mafic rocks. The regional significance of this metamorphic event is unclear but it may be related to dynamothermal metamorphism of the CCD. The contemporaneous emplacement of low-K gabbro, tonalite, and granodiorite and their spatial association with serpentinite, combined with published geochemical data, strongly suggest that the CCD represents an ensimatic arc. The Coal Creek Serpentinite is interpreted as a fragment of oceanic crust that formed either basement to the arc, or in a related back-arc or intra-arc setting. Combined field, U-Pb geochronologic, isotopic, and geochemical data indicate that the magmatic, metamorphic, and structural history of the CCD differs from that of coeval rocks elsewhere in the Llano uplift. The boundary between the CCD and deformed and metamorphosed granitic and supracrustal rocks to the north is a zone of intense mylonitization and polyphase deformation. This zone is interpreted as the structural boundary between the arc terrane and units to the north.

  7. Three-dimensional structural evolution and kinematics of the Piedemonte Llanero, Central Llanos foothills, Eastern Cordillera, Colombia

    NASA Astrophysics Data System (ADS)

    Egbue, Obi; Kellogg, James

    2012-11-01

    The Piedemonte Llanero is a wedge duplex zone in the Llanos foothills on the eastern flank of the Eastern Cordillera of Colombia. It is located northeast of the Cusiana and Cupiagua hydrocarbon fields. The area is characterized by a series of moderate to high-angle duplexes with east-southeast verging thin-skinned and thick-skinned tectonics. We present a structural model constrained by 2-D and 3-D seismic reflection data, surface geology, and well data. The structural analysis is based on backward modeling (kinematic restoration) and forward modeling using transfer-flexural slip and fault slip fold algorithms. The structures are significantly tighter in the northern segment compared to the southern segment of the overthrust trend. We estimate approximately 17 km of shortening in the northern duplex zone, and about 26 km total shortening for the southern duplex zone. We propose that thin-skinned in-sequence imbricate thrust stack deformation produced most of the shortening. The main Andean deformation (80% of the total shortening) commenced in the Piedemonte area about 6 Ma with rapid shortening and uplift in the area resulting in the development of an active-roof duplex structure as the cover was bulldozed forward by a horse block (Monterralo anticline) ramping up to a detachment at the base of C2, then ramping to the surface as the Yopal thrust. Later the horse blocks in the wedge rose, underthrusting the cover in a passive-roof duplex triangle zone. This was followed by an out-of-sequence Laramide-style thick-skinned basement-uplift of the range which produced much of the structural relief of the Eastern Cordillera. Cenozoic deformation in the Eastern Cordillera has been primarily range-normal, but has involved an increasing component of mountain-parallel right-lateral shear in the last 2 Ma.

  8. Mapping the Llano Estacado

    USDA-ARS?s Scientific Manuscript database

    Early maps of North America, prepared in the 18th and early 19th centuries, often depicted the Llano Estacado as a conspicuous blank spot - a terra incognita. A good example is a map of the southwest sketched by Alexander von Humboldt in 1804. In 1830, Stephen F. Austin added little detail to the ...

  9. Lithologic and hydrologic controls of mixed alluvial-bedrock channels in flood-prone fluvial systems: Bankfull and macrochannels in the Llano River watershed, central Texas, USA

    NASA Astrophysics Data System (ADS)

    Heitmuller, Franklin T.; Hudson, Paul F.; Asquith, William H.

    2015-03-01

    The rural and unregulated Llano River watershed located in central Texas, USA, has a highly variable flow regime and a wide range of instantaneous peak flows. Abrupt transitions in surface lithology exist along the main-stem channel course. Both of these characteristics afford an opportunity to examine hydrologic, lithologic, and sedimentary controls on downstream changes in channel morphology. Field surveys of channel topography and boundary composition are coupled with sediment analyses, hydraulic computations, flood-frequency analyses, and geographic information system mapping to discern controls on channel geometry (profile, pattern, and shape) and dimensions along the mixed alluvial-bedrock Llano River and key tributaries. Four categories of channel classification in a downstream direction include: (i) uppermost ephemeral reaches, (ii) straight or sinuous gravel-bed channels in Cretaceous carbonate sedimentary zones, (iii) straight or sinuous gravel-bed or bedrock channels in Paleozoic sedimentary zones, and (iv) straight, braided, or multithread mixed alluvial-bedrock channels with sandy beds in Precambrian igneous and metamorphic zones. Principal findings include: (i) a nearly linear channel profile attributed to resistant bedrock incision checkpoints; (ii) statistically significant correlations of both alluvial sinuosity and valley confinement to relatively high f (mean depth) hydraulic geometry values; (iii) relatively high b (width) hydraulic geometry values in partly confined settings with sinuous channels upstream from a prominent incision checkpoint; (iv) different functional flow categories including frequently occurring events (< 1.5-year return periods) that mobilize channel-bed material and less frequent events that determine bankfull channel (1.5- to 3-year return periods) and macrochannel (10- to 40-year return periods) dimensions; (v) macrochannels with high f values (mostly ≥ 0.45) that develop at sites with unit stream power values in excess

  10. Lithologic and hydrologic controls of mixed alluvial-bedrock channels in flood-prone fluvial systems: bankfull and macrochannels in the Llano River watershed, central Texas, USA

    USGS Publications Warehouse

    Heitmuller, Frank T.; Hudson, Paul F.; Asquith, William H.

    2015-01-01

    The rural and unregulated Llano River watershed located in central Texas, USA, has a highly variable flow regime and a wide range of instantaneous peak flows. Abrupt transitions in surface lithology exist along the main-stem channel course. Both of these characteristics afford an opportunity to examine hydrologic, lithologic, and sedimentary controls on downstream changes in channel morphology. Field surveys of channel topography and boundary composition are coupled with sediment analyses, hydraulic computations, flood-frequency analyses, and geographic information system mapping to discern controls on channel geometry (profile, pattern, and shape) and dimensions along the mixed alluvial-bedrock Llano River and key tributaries. Four categories of channel classification in a downstream direction include: (i) uppermost ephemeral reaches, (ii) straight or sinuous gravel-bed channels in Cretaceous carbonate sedimentary zones, (iii) straight or sinuous gravel-bed or bedrock channels in Paleozoic sedimentary zones, and (iv) straight, braided, or multithread mixed alluvial–bedrock channels with sandy beds in Precambrian igneous and metamorphic zones. Principal findings include: (i) a nearly linear channel profile attributed to resistant bedrock incision checkpoints; (ii) statistically significant correlations of both alluvial sinuosity and valley confinement to relatively high f (mean depth) hydraulic geometry values; (iii) relatively high b (width) hydraulic geometry values in partly confined settings with sinuous channels upstream from a prominent incision checkpoint; (iv) different functional flow categories including frequently occurring events (< 1.5-year return periods) that mobilize channel-bed material and less frequent events that determine bankfull channel (1.5- to 3-year return periods) and macrochannel (10- to 40-year return periods) dimensions; (v) macrochannels with high f values (most ≤ 0.45) that develop at sites with unit stream power values in excess

  11. Geochemistry and petrogenesis of Mesoproterozoic (~ 1.1 Ga) magmatic enclaves in granites of the eastern Llano Uplift, central Texas, USA

    NASA Astrophysics Data System (ADS)

    Smith, R. K.; Gray, Walt

    2011-07-01

    Mesoproterozoic (~ 1.1 Ga) plutons of the eastern Llano Uplift, central Texas, USA contain two types of magmatic enclaves (< 1% by vol.). Although volumetrically insignificant, the enclaves contain important petrogenetic information. Type I enclaves are felsic in composition (70-75 wt.% SiO2), with mineral assemblages and chemical compositions comparable with the host granites, but typically display a finer grained texture. They are interpreted as partly chilled disrupted material from the margins and roof of the plutons. Type II enclaves are intermediate in composition (~ 56-69 wt.% SiO2), with many elements defining trends continuous with the host granites. Both types of enclaves display sharp borders in contact with the host granite suggesting magma quenching with little or no physical exchange between host granite and enclave magma. Type II enclaves contained within the Marble Falls (MF) and Lone Grove (LG) plutons exhibit enrichments in Y, Nb, and Zr relative to their respective host granites. Enrichments in these incompatible trace elements at low SiO2, renders unlikely the possibility that the MF and LG Type II enclaves are the result of partial melting (anatexis) of mafic crustal rocks. Numerical modeling of fractional crystallization and simple mixing fails to explain the observed trace element trends. Because no coeval mafic to intermediate rocks are exposed in the uplift, characteristics of Type II enclave source magma(s) is uncertain. However, assuming source magmas similar to primitive continental arc basaltic andesite, trace-element trends (i.e., incompatible element enrichment and compatible element depletion) can be adequately replicated by a replenishment fractional crystallization (RFC) model. Chemistry of the MF and LG Type II enclaves suggest repeated replenishment of primitive magmas with only limited interaction with the host granitic magmas; the more primitive enclave magmas evolving in near chemical isolation by RFC processes. However

  12. [Bioecological characteristics of earthworm populations (Oligochaeta: Glossoscolecidae) in a natural and a protected savanna in the central Llanos of Venezuela].

    PubMed

    Hernández, Luis; Ojeda, Alonso; López-Hernández, Danilo

    2012-09-01

    In tropical savannas, the earthworm communities have a predominant role since they regulate the soil structure and dynamics of the organic matter. To study the effect on earthworm populations in two differently managed savannas, we compared the general aspects of the biology and ecology of earthworm populations from a 40 years protected savanna (SP) with no fire or cattle raising at the Estaci6n Biol6gica de los Llanos, Venezuela (EBLL), and a natural savanna (SNI), under normal burning and cattle raising management conditions. Sampling was carried out at the end of the dry season (April), and at the peak of the wet season (July-August). The main physical properties of soils per system were estimated. In each system, in plots of 90x90m, five fixed sampling units were selected at random; and at each sampling point one soil monolith of 25x25x30cm was collected per unit. Earthworms were extracted using the hand sorting extraction method; and the flotation method was used to estimate the density of cocoons. The earthworms were classified in different ecological categories considering their pigmentation, size and depth profile distribution. As a result of the savanna protection, physical parameters were modified in relation to SNI. The SP soils had higher soil moisture when compared to SNI. Soil moisture varied with depth during the dry season since, after the start of the rainy season, the soil was saturated. Field capacity in the SP was greater than that in the SNI. The surface apparent bulk density of soil was lower in the SP respect SNI, reflecting a lower soil compaction. Total average for the density and biomass of earthworms differed greatly, showing higher values in the SP. The earthworm density average in SP ranged between 25.6-85 individuals/m2 and the average biomass between 6.92-23.23g/m2. While in SNI, earthworms were only found in August, with a mean density of 22.40individuals/m2 and a mean biomass of 5.17g/m2. The vertical distribution pattern was only

  13. Petroleum geology of Llanos basin of Colombia

    SciTech Connect

    Sutherland, J.A.; Pena, L.E.; Munoz, F.; Cristancho, J.H.

    1989-03-01

    The Llanos basin is located in eastern Colombia between the Guyana shield and the Cordillera Oriental, the most easterly branch of the Andes. Currently, the basin produces 224,000 bbl of oil/day from a mixed marine and continental section that ranges in age from Cenomanian to Holocene and reaches over 7500 m in thickness. It is important to realize that until the Pliocene the basin lacked an independent existence; rather, it formed the nearshore sector of a much larger depocenter that opened westward to the Pacific and northward to the Caribbean. The bulk of the oil accumulated in the Llanos was probably generated outside the present basin from a much more extensive marine Cretaceous section that crops out in the Cordillera. Subsurface pressure data indicate that these rocks are now isolated from the Llanos, implying generation and primary migration before the elevation of the Cordillera in the early Pliocene. Oil accumulations are mostly fault controlled and fall into three classes. The giant Cano Limon complex in the north is closed against a lateral fault that appears to be a rejuvenation of a regional pre-Cretaceous normal fault. The central Llanos fields of Casanare are controlled by north-south-trending up-to-the-basin normal faults. The Apiay-Castilla fields to the south, a short distance from the mountain front, are located on an anticlinal trend bounded to the east by a high-angle reverse fault that also appears to have had horizontal movement. Oil gravity varies widely, from below 10/degree/ to 40/degree/ API, with most of the reserves in the 30/degree/ API range. However, with very few exceptions and regardless of the gravity, the oil has an abnormally low dissolved-gas content. To date, with relatively low density of drilling, over 1.3 billion bbl of oil have been discovered and prospects for further major discoveries are excellent.

  14. Evolution by Replenishment Fractional Crystallization (RFC) of Midproterozoic Magmatic Enclaves in Granites of the Eastern Llano Uplift, central Texas, U.S.A

    NASA Astrophysics Data System (ADS)

    Smith, R. K.; Gray, W.

    2009-12-01

    The Llano Uplift is a gentle structural dome exposing both island-arc and continental margin blocks emplaced along the southern margin of Laurentia during the Grenville orogeny (locally the Llano orogeny). These ~1370 to 1230 Ma metaigneous and metasedimentary rocks were subsequently intruded by a number of ~1119 to 1070 Ma post-to syntectonic granitic plutons collectively known as the Town Mountain Granite. The eastern most of these plutons (Lone Grove, Kingsland, and Marble Falls plutons) contain sparse microgranular magmatic enclaves of intermediate composition (56-68 wt.% SiO2). The enclaves display sharp borders in contact with the host granite suggesting magma quenching with little or no physical exchange between host granite and enclave magma. The origin of the enclave magma(s) is uncertain, as no synchronous mafic to intermediate rocks are exposed in the Uplift. New major- and trace-element analyses are providing clues as to the possible origins and evolution of the enclave magmas. Numerical modeling reveals that neither fractional crystallization nor simple mixing can explain the trace-element trends. However, assuming source magmas similar to primitive continental arc andesites, the trends can be adequately replicated by a replenishment fractional crystallization(RFC) model. The model assumes that replenishment/hybridization events are accompanied by 20%-30% fractionation of plagioclase + clinopyroxene + magnetite. Modeling further reveals that results are relatively insensitive to the number of replenishment events (from 50 to 1000), as well as perturbations in the mineral percentages, suggesting that RFC is a very plausible and robust explanation for the chemical evolution of the enclaves. As suggested by Weibe et al. (1997), RFC and lack of magma exchange may be indicative of enclave magma ponding and hybridization at the base of the host granite magma chamber, followed by occasional dispersment into the host granite. Origin from a primitive

  15. Mapping the Llano Estacado of North America

    USDA-ARS?s Scientific Manuscript database

    The Llano Estacado is a commonly recognized physiographic region in North America. Renowned for its remarkably level surface and the towering escarpments along its outer margins, the elevated plains of the Llano Estacado form an immense tableland that stands in high relief at the southern end of the...

  16. Related oil and gas production north of the Llano Uplift

    SciTech Connect

    Jackson, T.C.

    1980-01-01

    This work is an abbreviated collection of anecdotes, theories, and facts concerning the relationship between the Llano Uplift and hydrocarbon production in N. McCulloch, S. Coleman, and most of Brown County, Texas. Due to the paucity of published information on oil and gas production in this area, material gathered for this work came from interviews with petroleum geologists and engineers who have extensive knowledge of the subject area. The Precambrian batholithic intrusion, referred to as the Llano Uplift, is the dominante structural feature in central Texas. Regionally, the formation, migration and entrapment of oil and gas, as well as the rocks from which they are produced, have been directly or indirectly affected by this uplift. Its significance may be seen in the fact that each producing formation in the area exhibits some kind of change in its nature as it approaches the uplift. This change may be in the form of formation thickness, rock composition, faulting, or simply depth from surface.

  17. Oil geochemistry of the northern Llanos Basin, Colombia. A model for migration

    SciTech Connect

    Ramon, J.C.; Dzou, L.

    1996-12-31

    The chemical composition of 23 crude oils and one oil seep from Llanos Basin, Colombia were studied in detail by geochemical methods in order to understand their genetic relationship. A filling history model is proposed to explain the observed composition variations in Llanos Basin oils. Geochemical fingerprinting indicates that there are six families of crude oils. The biomarker compositions have been used to identify characteristics of the source rocks. The Llanos oils contain marine algal- derived {open_quotes}C30 steranes{close_quotes} (i.e., 24-n-propylcholestanes), which are diagnostic for oils generated from marine Cretaceous source rocks. A significant HC-contribution from a Tertiary source is also indicated by the presence of high concentration of the {open_quotes}flowering plant{close_quotes}-markers oleanane, bicadinanes and oleanoids. Low DBT/Phen, %sulfur values and high diasteranes concentration indicate that the source rock is clay-rich. Biomarker maturity parameters indicate a wide range of source-rock thermal maturities from early to late oil window. Heavy biodegradation has been particularly common among the first oils to fill reservoirs in central Llanos oil fields. The older altered heavy oils were mixed with a second pulse of oil explaining the wide range of oil gravities measured in the central Llanos Basin.

  18. Oil geochemistry of the northern Llanos Basin, Colombia. A model for migration

    SciTech Connect

    Ramon, J.C. ); Dzou, L. )

    1996-01-01

    The chemical composition of 23 crude oils and one oil seep from Llanos Basin, Colombia were studied in detail by geochemical methods in order to understand their genetic relationship. A filling history model is proposed to explain the observed composition variations in Llanos Basin oils. Geochemical fingerprinting indicates that there are six families of crude oils. The biomarker compositions have been used to identify characteristics of the source rocks. The Llanos oils contain marine algal- derived [open quotes]C30 steranes[close quotes] (i.e., 24-n-propylcholestanes), which are diagnostic for oils generated from marine Cretaceous source rocks. A significant HC-contribution from a Tertiary source is also indicated by the presence of high concentration of the [open quotes]flowering plant[close quotes]-markers oleanane, bicadinanes and oleanoids. Low DBT/Phen, %sulfur values and high diasteranes concentration indicate that the source rock is clay-rich. Biomarker maturity parameters indicate a wide range of source-rock thermal maturities from early to late oil window. Heavy biodegradation has been particularly common among the first oils to fill reservoirs in central Llanos oil fields. The older altered heavy oils were mixed with a second pulse of oil explaining the wide range of oil gravities measured in the central Llanos Basin.

  19. 76 FR 67397 - Radio Broadcasting Services; Llano, Texas

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-01

    ... COMMISSION 47 CFR Part 73 Radio Broadcasting Services; Llano, Texas AGENCY: Federal Communications Commission... Allotments by substituting Channel 242C3 for vacant Channel 293C3, at Llano, Texas. The proposal is part of a... required for the allotment of Channel 242C3 at Llano, Texas, because the proposed allotment is located...

  20. Grassland ecosystems of the Llano Estacado

    Treesearch

    Eileen Johnson

    2007-01-01

    The Llano Estacado, or Southern High Plains, has been a grassland throughout the Quaternary. The character of this grassland has varied through time, alternating between open, parkland, and savannah as the climate has changed. Different lines of evidence are used to reconstruct the climatic regimes and ecosystems, consisting of sediments and soils, vertebrate and...

  1. Cambrian paleomagnetism of the Llano Uplift, Texas

    NASA Astrophysics Data System (ADS)

    Watts, Doyle R.; van der Voo, Rob; Reeve, Scott C.

    1980-10-01

    Late Cambrian sandstones and limestones sampled from various members of the Riley and Wilberns formations of the Llano uplift show a progression of paleomagnetic pole positions as a function of age. The members, ages, and poles are the following for the Riley Formation: the Hickory Sandstone, Lower Dresbachian, 34°N, 145°E; the Cap Mountain Limestone, Dresbachian, 33°N, 140°E; the Lion Mountain Limestone, Upper Dresbachian, 24°N, 146°E. For, the Wilberns Formation they are the following: the Welge Sandstone/Morgan Creek Limestone, Lower and Middle Franconian, 24°N, 151°E; and the Point peak Shale, Upper Franconian, 6°N, 159°E. These poles are based on thermal, chemical, and alternating field demagnetizations and on vector analysis. Most directions are interpreted to be of reversed polarity, but the Cap Mountain Limestone also yielded normal polarity directions; all directions resided in hematite with blocking temperatures up to 680°C. Almost all Cambrian poles appear to fall in a broad streak between the equator at about 155°E (e.g., the poles from the Tapeats Sandstone and from the Late Cambrian Point Peak Shale of the Wilberns Formation) and about 60°N, 90°E, where Cambrian poles have been obtained by Elston and Bressler (1977) and French et al. (1977). Although, at the present time, partial to complete remagnetization or nondipole behavior of the geomagnetic field are adequate ad hoc hypotheses to explain some of the data, it is suggested that the simplest and most unifying hypothesis to explain all data involves a Cambrian loop of apparent polar wander with respect to North America. This loop occurs before the middle Late Cambrian, with the poles from the Llano uplift falling on the return track.

  2. Precambrian extension in the Llano Uplift, Texas

    SciTech Connect

    Carter, K.E. . Dept. of Geology); Reese, J.; Helper, M.A. . Dept. of Geological Sciences)

    1993-02-01

    Grenville-age, post-collisional extension in the southeastern Llano Uplift is recorded by extensional differentiation crenulation cleavages, boudinaged and folded veins, quartz fibers, folds and associated axial planar foliations. These structures overprint three (D[sub 1], D[sub 2], and D[sub 3]) distinct deformation phases linked to crustal shortening, and preserve evidence of an evolution from NE-directed noncoaxial shortening through N-S extension. A WNW-trending extensional crenulation cleavage (S[sub ext]), with top-down-to-the-south shear-sense, crenulates the regionally dominant S[sub 2] foliation. In some domains a similarly trending extensional cleavage crenulates S[sub 3], but shows top-down-to-the-NE motion. Folds associated with S[sub ext] are boudinaged, whereas veins at steeper angles are folded. Quartz fibers in en echelon veins are oriented normal to S[sub ext] surfaces and are parallel to the extension direction of boudins. These structures are consistent with top-down-to-the-south motion that would occur under a N-S extension. A crosscutting extensional crenulation cleavage trends NW and shows top-down-to-the-SW motion. Folds associated with this cleavage trend NNW and fold pre-existing structures. Extensional fabrics are overprinted by cordierite and statically recrystallized biotite associated with later granite plutonism. The geometry, shear-sense, and relative age of all late ductile structures are consistent with N-S extension and may reflect collapse of Llano crust following earlier contractional phases of the Grenville orogeny.

  3. Rb-Sr dating of a paleosol, Llano Uplift, Texas

    SciTech Connect

    Long, L.E.; Agee, W.N. Jr.

    1985-01-01

    A red, oxidized, clay-rich paleosol is locally developed upon 1.2 Ga old Packsaddle Schist in the eastern Llano Uplift, central Texas. This soil, which differs from organic-rich soil of recent origin, evidently formed under moist tropical conditions. Bounding the area on the east side is a retreating escarpment of early cretaceous limestone resting directly upon basement; thus the age of the paleosol must be late Cretaceous or younger. Ultra-fine fractions (<0.05 micrometers) from the paleosol consist of clay high in Al/sub 2/O/sub 3/ (30 wt%) with very low K/sub 2/O (0.7%). Aliquots were treated with solutions of ammonium acetate, silver thiourea, or dodecyl- or hexadecylammonium chloride to displace the loosely-bound Rb and Sr present in clay interlayers. These reagents remove all readily exchanged ions immediately, and their attack on the clay structure continues to an extent that depends upon the reagent and duration of the application. The result, after chemical treatment, is a Rb-Sr isochron based upon data from a single sample. The isotopic data argue for a consistent interpretation. Initial /sup 87/Sr//sup 86/Sr at different sample sites is high and variable, as expected in a soil that weathered from ancient, inhomogeneous bedrock. The age of ultrafine material from a locality 8 km form the Cretaceous escarpment is 51 +/- 3 Ma, whereas at a site 3 km from the escarpment the age is 27 +/- 1 Ma. However, the apparent age of the 0.2-0.1 micrometer size fraction from the latter sample is 50 +/- 4 Ma, suggesting inheritance of radiogenic Sr from the substrate.

  4. Raptor abundance and distribution in the Llanos wetlands of Venezuela

    USGS Publications Warehouse

    Jensen, W.J.; Gregory, M.S.; Baldassarre, G.A.; Vilella, F.J.; Bildstein, K.L.

    2005-01-01

    The Llanos of Venezuela is a 275 000-km2 freshwater wetland long recognized as an important habitat for waterbirds. However, little information exists on the raptor community of the region. We conducted raptor surveys in the Southwestern and Western Llanos during 2000-02 and detected 28 species representing 19 genera. Overall, areas of the Llanos that we sampled contained 52% of all raptor species and more than 70% of the kites, buteos, and subbuteos known to inhabit Venezuela. Regional differences in the mean number per route for four of the 14 most common species, the Crested Caracara (Caracara plancus), Black-collared Hawk (Busarellus nigricollis), American Kestrel (Falco sparverius), and Osprey (Pandion haliaetus), were significant (P < 0.0018) in relation to the wet or dry seasons. Of the 14 less common species, six were detected in only one season (wet or dry). The Southwestern and Western regions of the Llanos support a rich raptor community composed primarily of nonmigratory wetland-dependent and upland-terrestrial species. ?? 2005 The Raptor Research Foundation, Inc.

  5. 77 FR 32900 - Radio Broadcasting Services; Llano, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-04

    ... COMMISSION 47 CFR Part 73 Radio Broadcasting Services; Llano, TX AGENCY: Federal Communications Commission... Congressional Review Act, see U.S.C. 801(a)(1)(A). List of Subjects in 47 CFR Part 73 Radio, Radio broadcasting...: PART 73--RADIO BROADCAST SERVICES 0 1. The authority citation for part 73 continues to read as...

  6. Integrated multiple image GIS application to the regional geologic interpretation of the Llano Uplift region, Texas

    SciTech Connect

    Gobel, V.W.; Clark, M.; McDonald, D. )

    1993-03-01

    GIS applications have been developed that can be used in regional geologic analysis. The techniques can discriminate lithologic boundaries expressed in images that capture morphologic features resulting from the interaction between surface shaping agents and crustal rocks. Study area selected is the Llano Uplift region, central Texas, a highly suitable test site because of (1) the availability of reliable, repeatable ground control; (2) a moderate topography reflecting complex multi-phase deformational periods; and (3) the lack of large scale geologic maps that would allow a unified interpretation of the region. The objectives are (1) the recognition of strain features being the results of deformational processes that affected basement and cover rocks; (2) the development of methodology to perform this recognition involving the integration of multispectral images, space shuttle photography, and geologic ground control in a GIS database. It is demonstrated that it is feasible to undertake regional geologic interpretations utilizing an integrated GIS database.

  7. Discovery of Cano Limon field, Llanos basin, Colombia

    SciTech Connect

    McCollough, C.N.

    1988-02-01

    After 40 years of sporadic exploration that yielded negative or marginal results, the Llanos basin of eastern Colombia was thrust to the forefront of world attention by the discovery of the supergiant Cano Limon field in July 1983. This discovery culminated an intensive 3-year exploration effort by Occidental involving 4000 km of dynamite seismic, 20 stratigraphic tests from 1300 to 3500 ft deep, and 13 exploratory wells. Cost prior to discovery was $45 million. The Llanos is an oily basin with abundant excellent reservoir sands. The problem has been to define traps. The basin deep lies along the foot of the eastern Cordillera, from which a sediment thickness of 30,000 ft thins gradually to the east on a homoclinal flank terminating at the Guyana shield. Except for the very young folding along the Andean front, structural traps are generally sparse and subtle. An exception is the Cano Limon area, which is dominated by major early Tertiary northeast-southwest strike-slip faulting. Concurrent folding and fault sealing formed Cano Limon and other smaller fields. The Cano Limon field with its other half, the Guafita field in Venezuela, contains an estimated initial potential of 3160 million bbl of oil, of which about 1460 million bbl is expected to be recovered. The bulk of the oil is in deltaic sands of the Eocene Mirador with additional reservoirs in the Upper Cretaceous and the Oligocene Carbonera Formation.

  8. Petroleum system of the Cano Limon field, Llanos Basin, Colombia

    SciTech Connect

    Molina, J.

    1996-08-01

    The Chipaque-Lower Carbonera({circ}) Petroleum System of the northernmost Llanos Basin of Colombia, covers 11,100 km{sup 2} and includes two major oil fields: Caho Limon in Colombia, and Guafita in Venezuela, jointly with three more relatively small fields in Colombia: Redondo, Cano Rondon, and Jiba. Ultimate recoverable reserves are in the order of 1.4 BBO. The sedimentary section penetrated in the Northern Llanos has been informally subdivided into four Cretaceous formations: K3, K2B, K2A, and Lower K1 deposited during the Albian-Senonian, and into four Tertiary formations: Lower Carbonera, Upper Carbonera, Leon, and Guayabo deposited during the Late Eocene to Pliocene time. The main reservoir is the Lower Carbonera Formation, which contains 81% of the total reserves. The Cretaceous K2A and Lower K1 reservoirs contain 6% and 8%, respectively of the reserves. Minor reserves are accumulated in the discontinuous sandstones of the Oligocene Upper Carbonera Formation Geochemical analyses of the Cano Limon/Guafita oils indicate that these are aromatic intermediate to paraffinic-naphthenic, non degradated, genetically related to a common marine-derived type of kerogen. These oils were generated by a mature, marine clastic source rock with a small contribution of continental organic matter. The geochemistry of the hydrocarbon suggest a genetic relationship with the shales of the Chipaque formation, basin-ward equivalent of the K2 Formation, which presents kerogen type II organic matter and has been recognized as a good source rock. The petroleum system is hypothetical because a definite oil-source rock correlation is lacking. The development of the petroleum system is directly related to the history of movement of the Santa Maria, La Yuca, Caho Limon, and Matanegra wrench faults. It has been determined that these faults of pre-Cretaceous rifting origin, created the Santa Maria Graben of which the Espino Graben is the continuation in Venezuela.

  9. Geology of supergiant Cano Limon field and Llanos basin, Colombia

    SciTech Connect

    McCollough, C.N.; Padfield, E.P.

    1986-07-01

    After 40 years of sporadic exploration that yielded negative or marginal results, the Llanos basin of eastern Colombia was thrust to the forefront of world attention by the discovery of the supergiant Cano Limon field in July 1983. This discovery culminated an intensive 3-year exploration effort by Occidental involving 4000 km of dynamite seismic, 20 stratigraphic tests from 1300 to 3500 ft deep, and 13 exploratory wells. Cost prior to discovery was $45 million. The Llanos is an oily basin with abundant excellent reservoir sands. The problem has been to define traps. The basin deep lies along the foot of the eastern Cordillera, from which a sediment thickness of 30,000 ft thins gradually to the east on a homoclinal flank terminating at the Guyana shield. Except for the very young folding along the Andean front, structural traps are generally sparse. An exception is the Cano Limon area, which is dominated by major early Tertiary northeast-southwest strike-slip faulting. Concurrent folding and fault sealing formed Cano Limon and other smaller fields. The Cano Limon field with its other half, the Guafita field in Venezuela, contains an estimated initial potential of 3160 million bbl of oil, of which about 1460 million bbl is expected to be recovered. The bulk of the oil is in deltaic sands of the Eocene Mirador with additional reservoirs in the Upper Cretaceous. Average porosity of the Mirador is 24%, permeability is 4 darcies, and water saturation is 24%. The average initial flow rate of the first 15 wells is 10,000 BOPD. Exploration opportunities exist in a deep unexplored Paleozoic rift, in stratigraphic traps of Cretaceous and Tertiary age, and in fault-related traps along the basin flanks.

  10. Petrologic significance of staurolites in the Llano Uplift

    SciTech Connect

    Carlson, W.D.; Reese, J.F. . Dept. of Geological Sciences)

    1993-02-01

    The recent discovery of rocks with near-end-member Fe-staurolite in the SE Llano Uplift, together with the regional absence of Fe-Mg staurolite except as inclusion in garnet in a single nearby locality, confirms that the SE Uplift experienced a polybaric metamorphic history similar to that documented for the N and NW Uplift. The units containing Fe-rich staurolite are part of a unique suite of rocks within the Packsaddle Group (Rough Ridge Fm) exposed in Whites Creek. Although the predominant rock types in the Packsaddle Schist are felsic schists, felsic gneisses and amphibolites, this pelitic metasedimentary package includes interlayered andalusite-bearing rocks, quartzites, and muscovite schists. Although textural evidence is equivocal, growth of staurolite during dynamothermal metamorphism is indicated by the preferred orientation of elongate crystals parallel to the rock's dominant foliation. The unusual Fe-rich staurolites reported here are the only known occurrence of the mineral in the Uplift except for staurolite (X[sub Fe] = 0.72) described as inclusions within a large garnet from a locality in the Rough Ridge Fm [approximately]3 km to the west. The matrix surrounding this garnet is entirely devoid of staurolite. The contrast between these occurrences indicates that staurolite of ordinary Fe/Mg ratio grew during an early moderate-P to high-P dynamothermal episode, but was destroyed during later low-P static metamorphism. In contrast, near-end-member Fe-staurolite originating in the early event survived later static metamorphism. These observations are consistent with the polybaric history (dynamic metamorphism at P[>=] [approximately]6--8 kbar followed by static recrystallization at P[approximately]2--3 kbar) deduced from assemblages, textures and thermobarometry on metamafic rocks from the N and NW Llano Uplift.

  11. Flow of formation waters in the cretaceous-miocene succession of the Llanos basin, Colombia

    SciTech Connect

    Villegas, M.E.; Ramon, J.C.; Bachu, S.; Underschultz, J.R.

    1994-12-01

    This study presents the hydrogeological characteristics and flow of formation waters in the post-Paleozoic succession of the Llanos basin, a mainly siliciclastic foreland sub-Andean sedimentary basin located in Columbia between the Cordillera Oriental and the Guyanan Precambrian shield. The porosity of the sandy formations is generally high, in the range of 16-20% on average, with a trend of decreasing values with depth. Permeabilities are also relatively high, in the 10{sup 2} and 10{sup 3} md range. THe salinity (total dissolved solids) of formation waters is generally low, in the 10,000-20,000 mg/L range, suggesting that at least some strata in the basin have been flushed by metoeoric water. The shaly units in the sedimentary succession are weak aquitards in the eastern and southern parts of the basin, but are strong in the central-western part. The pressure in the basin is close to or slightly subdepth, particularly in the central-western area. The flow of formation waters in the upper units is driven mainly by topography from highs in the southwest to lows in the northeast. Local systems from the foothills and from local topographic highs in the east feed into this flow system. The flow of formation waters in the lower units is driven by topography only in the southern, eastern, and northern parts of the basin. In the central-western part, the flow is downdip toward the thrust-fold belt, driven probably by pore-space rebound induced by erosional unloading, which also is the cause of underpressuring. Hydrocarbons generated in the Cretaceous organic-rich, shaly Gacheta Formation probably have migrated updip and to the north-northeast, driven by buoyancy and entrained by the topography-driven flow of formation waters in Cretaceous-Oligocene strata in the central-western part of the basin could have created conditions for hydrodynamic entrapment of hydrocarbons.

  12. Stratigraphic controls on the source rock distribution, Llanos Orientales Basin, Colombia

    SciTech Connect

    Ramon, J.C.; Fajardo, A.; Rubiano, J.; Reyes, A. )

    1996-01-01

    All available rock and oil geochemistry analyses were tied to a high-resolution stratigraphic framework for more than 50 wells in the Central Llanos Orientates Basin. New Tertiary generation input is proposed. The best source rock intervals are at the base and top of the Gacheta Formation (Upper Cretaceous) and in the middle of the Barco-Cuervos (Paleocene) and Mirador (Eocene) formations. These organic-rich zones contain type II and III kerogen. TOC contents range from about 1% up to 15%. The four source rock intervals occur within marine shales near condensed sections, at the position maximum accommodation/sediment-supply (A/S) ratios. The development of conditions that allow accumulation and preservation of anomalously high fractions of organic matter might be explained by two mechanisms. Increased A/S ratio results in retention of more sediment in the coastal plain, thus reducing the tendency for siliciclastic sediment to dilute the organic matter accumulating on the shelf. Also, deeper water might restrict circulation, enhancing bottom anoxic conditions. In the more transitional and continental sequences, increased A/S ratio is associated with higher phreatic water level. A high ground water table enhances preservation of coaly intervals. The sea-level rise brings marine water into valleys and low-gradient coastal plains. The resulting embayments, marsh and swampy areas are organic-prone, contributing to the source rock potential of strata associated with high conditions and base-level rise-to-fall turnaround positions.

  13. Stratigraphic controls on the source rock distribution, Llanos Orientales Basin, Colombia

    SciTech Connect

    Ramon, J.C.; Fajardo, A.; Rubiano, J.; Reyes, A.

    1996-12-31

    All available rock and oil geochemistry analyses were tied to a high-resolution stratigraphic framework for more than 50 wells in the Central Llanos Orientates Basin. New Tertiary generation input is proposed. The best source rock intervals are at the base and top of the Gacheta Formation (Upper Cretaceous) and in the middle of the Barco-Cuervos (Paleocene) and Mirador (Eocene) formations. These organic-rich zones contain type II and III kerogen. TOC contents range from about 1% up to 15%. The four source rock intervals occur within marine shales near condensed sections, at the position maximum accommodation/sediment-supply (A/S) ratios. The development of conditions that allow accumulation and preservation of anomalously high fractions of organic matter might be explained by two mechanisms. Increased A/S ratio results in retention of more sediment in the coastal plain, thus reducing the tendency for siliciclastic sediment to dilute the organic matter accumulating on the shelf. Also, deeper water might restrict circulation, enhancing bottom anoxic conditions. In the more transitional and continental sequences, increased A/S ratio is associated with higher phreatic water level. A high ground water table enhances preservation of coaly intervals. The sea-level rise brings marine water into valleys and low-gradient coastal plains. The resulting embayments, marsh and swampy areas are organic-prone, contributing to the source rock potential of strata associated with high conditions and base-level rise-to-fall turnaround positions.

  14. Comparative thermometry on pelitic rocks and marbles of the Llano uplift, Texas

    SciTech Connect

    Letargo, C.M.R.; Lamb, W.M. . Dept. of Geology)

    1992-01-01

    The Llano Uplift in central Texas is a Grenville-aged metamorphic complex consisting of amphibolite facies assemblages whose development has been attributed to the emplacement of granite plutons between 1.0--1.1 Ga. Temperatures have been obtained from garnet-biotite, garnet-ilmenite, and calcite-dolomite pairs as well as from various silicate equilibria. Application of these geothermometers yield consistent results and are thus indicative of peak conditions attending the amphibolite facies metamorphism. Temperature determined using garnet-biotite and garnet-ilmenite thermometry compare favorably with calcite-dolomite temperatures obtained from marbles in contact with granite plutons in the southeastern part of the uplift. The highest calcite-dolomite temperatures of [approximately]600 C are obtained from marbles containing an isobarically invariant assemblage consisting of calcite + dolomite + diopside + tremolite + forsterite. At pressures of 2--3 kbar, this isobarically invariant assemblage will be stable at a temperature range of [approximately]600--650 C. Also in close proximity to granites in the southeast uplift is the assemblage muscovite + quartz + k-feldspar + sillimanite [approximately] andalusite which indicate T 650 C and P 2.5 kbar. Assemblages consisting of garnet + sillimanite + quartz + plagioclase (GASP) and garnet + rutile + ilmenite + plagioclase + quartz (GRIPS) are currently being studied to provide additional constraints on pressures of amphibolite facies metamorphism.

  15. Historical survey of the national astronomical observatory in Llano del Hato

    NASA Astrophysics Data System (ADS)

    Martinez Picar, Antonio; Salas Ramirez, Henry

    2007-12-01

    The Centro de Investigaciones de Astronomia (CIDA), the Venezuelan Institute in charge for managing human- and technical resources of the National Astronomical Observatory in Llano del Hato, is one of the younger institutes in its field. However, its foundation is surrounded by a series of curious and interesting eyents that go back to the end of the 18th century. Its equatoriallocation, excellent astronomical equipment and the high-qualified personnel offers a geographical and technical advantage. The paper is a historical oveniew of events, facts and demonstrations of the human activity related to the conception, building and starting the Llano del Hato National Astronomical Observatory.

  16. Petroleum geology of the Cusiana Field, Llanos Basin Foothills, Colombia

    SciTech Connect

    Cazier, E.C.; Hayward, A.B.; Espinosa, G.

    1995-10-01

    Cusiana field is located in the Llanos Foothills, 150 mi (240km) northeast of Bogota, Colombia. Light oil, gas, and condensate in Cusiana occur at drilling depths that average 15,000 ft (4575 m) in an asymmetric, hanging-wall anticlinal trap 15 mi (25 km) long and 3-4 mi (5-6 km) across, formed during the Miocene-Holocene deformation of the Eastern Cordillera. Top and lateral seals are provided by marine mudstones of the Oligocene Carbonera Group, and support a hydrocarbon column of over 1500 ft (460 m). Biomarker data from the hydrocarbons indicate a marine mudstone source interpreted to be the Turonian-Coniacian Gacheta Formation. Over 50% of the reserves occur in upper Eocene Mirador Formation sandstones, which were deposited predominantly in estuarine environments. Additional, deeper reservoirs include estuarine sandstones of the Paleocene Barco Formation and the shallow-marine Santonian-Campanian Upper Guadalupe Sandstone. Porosity in Cusiana is relatively low. Good permeability is retained, however, because the reservoirs are pure quartz-cemented quartzarenites that lack permeability-reducing authigenic clays and carbonate cements. Core and well test analyses indicate matrix permeability, not fracture permeability, provides the high deliverability of Cusiana wells. Cusiana hydrocarbon phases exist in a near-miscible, critical-point state. Reservoir simulation indicates very high liquid hydrocarbon recoveries should be possible from all reservoirs by using the reinjection of produced gas to maintain reservoir pressure and to vaporize residual liquids. The field contains up to 1.5 MSTB of hydrocarbon liquid reserves and 3.4 Tcf of gas.

  17. Stratotype for the Mérida Glaciation at Pueblo Llano in the northern Venezuelan Andes

    NASA Astrophysics Data System (ADS)

    Mahaney, W. C.; Milner, M. W.; Voros, J.; Kalm, V.; Hütt, G.; Bezada, M.; Hancock, R. G. V.; Aufreiter, S.

    2000-12-01

    The Mérida Glaciation (cf. Wisconsinan, Weichselian) as proposed by Schubert (1974b) culminated at about 18 ka during the last glacial maximum (LGM) and ended at about 13 ka as indicated by 14C dating and correlation with the Cordillera Oriental of Colombia. Moraines of an early stade of Mérida Glaciation reached to 2800 m a.s.l. and were largely overrun or eradicated by the maximum Wisconsinan advance (LGM); where they outcrop, the older moraines are characterized by eroded, weathered glacial diamictons and outwash fans. At Pueblo Llano in the central Mérida Andes (Cordillera de Trujillo), older to younger beds of contorted glacitectonized diamict, overlying beds of bouldery till and indurated outwash, all belong to the early Mérida stade. Overlying the early Mérida stade, deposits of rhythmically bedded glaciolacustrine sediments are in turn overlain with contorted sand and silt beds capped with outwash. Above the outwash terrace a loop moraine of LGM age completely encircles the margins of the basin. A stream cut exposed by catastrophic (tectonic or surge?) release of meltwater displays a lithostratigraphic succession that is bereft of organic material for radiocarbon dating. Five optically-stimulated luminescence (OSL) dates place the maximum age of the lowest till at 81 ka. Particle size distributions allow clear distinctions between major lithic units. Heavy mineral analysis of the middle and lower coarse units in the section provide information on sediment sourcing and on major lithostratigraphic divisions. Trace element concentrations provide information on the relative homogeneity of the deposits. The HREE (heavy rare earth element) concentrations allow discrimination of the lower till from the rest of the section; the LREE (light rare earth element) concentrations highlight differences between the lower till, LGM till, and the rest of the section.

  18. Coal Creek serpentinite, Llano Uplift, Texas: A fragment of an incomplete Precambrian ophiolite

    NASA Astrophysics Data System (ADS)

    Garrison, James R., Jr.

    1981-05-01

    The Precambrian Coal Creek serpentinite, Llano Uplift, Texas, occurs within the upper part of the Packsaddle Schist, which appears to represent a thick sequence of shelf-edge volcaniclastic arc-flank metasediments. The serpentinite has a foliation defined by lizardite pseudomorphs after original foliated harzburgite tectonite, which deviates as much as 15° from the regional country-rock foliation. A few samples contain the relict assemblage olivine + orthopyroxene + anthophyllite reflecting re-equilibration to regional metamorphic conditions near 710 °C at ˜3.5 kb. Oxygen and deuterium isotopic data indicate the lizardite could have formed in equilibrium with magmatic water at about 300 to 400 °C during regional uplift. A likely petrogenetic model involves the olistostromal emplacement of a fragment of ophiolitic material, the Coal Creek ultramafic body, into the volcaniclastic arc-flank sediments. The island-arc model suggested for the Llano Uplift and the existence of ophiolitic material imply that brittle plate collisions were locally important 1,200 m.y. ago and that the orogenic event that affected the Llano terrane (that is, the Grenvillian orogeny) involved island-arc-continent interactions. The Llano Uplift contains the only exposed ophiolitic material along the entire “Grenvillian” orogenic belt. *Present address: School of Geology and Geophysics, University of Oklahoma, Norman, Oklahoma 73019

  19. The giant Cano Limon field, Llanos basin, Colombia

    SciTech Connect

    McCollough, C.N.; Carver, J.A. )

    1990-09-01

    The giant Cano Limon field was discovered in July 1983. The discovery was the culmination of a 3-yr exploration effort by Occidental involving 4000 km of dynamite seismic, 20 stratigraphic tests from 396 to 1,067 m deep, and 12 exploratory wells. Prior to Oxy's entering the area, there had been 61 exploratory wells drilled with meager results, namely two fields with total reserves of about 20 million bbl of light oil and one field with reserves of 90 million bbl of 13.6{degree} API oil-none of which were commercial. The Llanos basin was known for its abundant excellent reservoir sandstones and opinions varied as to whether there was adequate source rock. The major problem had been defining traps. Except for the very young folding along the Andean front, the known structural traps were sparse and subtle. Most of the exploration had been done in the western part of the basin near the basin deep or in the Andean foothills. Occidental took a very large acreage position east of the area of past exploration efforts and found an exception to the small fault closures known elsewhere in the basin. This exception, the Cano Limon area, is dominated by major early Tertiary northeast-southwest strike-slip faulting. Concurrent folding in combination with fault sealing formed the Cano Limon field and other much smaller fields in the area. The Cano Limon field, encompassing 3,570 ha, contains an estimated 1.8 billion bbl of oil in place, of which 1.6 billion bbl are expected to be recovered with the very strong natural water drive. The bulk of the oil is in deltaic sandstones of the Eocene Mirador formation with additional reservoirs in the Upper Cretaceous. The average porosity of the Mirador is about 25%, the permeability is about 5 d, and water saturation is about 23%. Individual well flow rates have exceeded 20,000 BOPD. The average oil gravity is 29.5{degree} API, with a GOR of 8 ft3/bbl and sulfur content of 0.41%. Current production is about 230,000 bbl/day.

  20. Detection of near-surface horizontal anisotropy in a weathered metamorphic schist at Llano Uplift (Texas) by transient electromagnetic induction

    NASA Astrophysics Data System (ADS)

    Collins, Jamie L.; Everett, Mark E.; Johnson, Brann

    2006-10-01

    The use of transient controlled-source electromagnetic prospecting to detect buried, steeply dipping foliation in metamorphic rocks is illustrated with data acquired over the Precambrian Packsaddle schist in the Llano Uplift of central Texas. The azimuthal variation of the transient voltage at a given transmitter-receiver separation about a fixed central point is consistent with the forward model response of a homogeneous halfspace exhibiting horizontal electrical anisotropy. The loop-loop exploration configuration is ideally suited to probe horizontal anisotropy. A quantitative match of the forward response to the observed data produces reasonable electrical conductivity values and coefficient of anisotropy for resistive, crystalline geological materials. The most conductive direction consistently lies within a few degrees of the geologically mapped foliation strike direction. The electrical anisotropy is strongest below the near-surface weathered layer, within the more competent bedrock. The agent responsible for generating the anistropy cannot be definitively determined, because it is likely to be a combination of geological factors, such as weathering, compositional banding and microcracking, all of which enhance electrical conductivity parallel to the plane of foliation. The transient electromagnetics is supplemented by DC resistivity and seismic surveys. The elastic anisotropy is evident in the near-surface weathered layer, but it may not persist very deep into the underlying competent schist. The exposure of foliated schist at the surface is not sufficient to rule out a possible role for systematically aligned macrofracture sets as a secondary cause of the observed anisotropy.

  1. An optical luminescence chronology for late Pleistocene aeolian activity in the Colombian and Venezuelan Llanos

    NASA Astrophysics Data System (ADS)

    Carr, Andrew S.; Armitage, Simon J.; Berrío, Juan-Carlos; Bilbao, Bibiana A.; Boom, Arnoud

    2016-03-01

    The lowland savannas (Llanos) of Colombia and Venezuela are covered by extensive aeolian landforms for which little chronological information exists. We present the first optically stimulated luminescence (OSL) age constraints for dunes in the Llanos Orientales of lowland Colombia and new ages for dunes in the Venezuelan Llanos. The sampled dunes are fully vegetated and show evidence of post-depositional erosion. Ages range from 4.5 ± 0.4 to 66 ± 4 ka, with the majority dating to 27-10 ka (Marine Isotope Stage 2). Some dunes accumulated quickly during the last glacial maximum, although most were active 16-10 ka. Accretion largely ceased after 10 ka. All dunes are elongated downwind from rivers, parallel with dry season winds, and are interpreted as source-bordering features. As they are presently isolated from fluvial sediments by gallery forest it is proposed that activity was associated with a more prolonged dry season, which restricted gallery forest, leading to greater sediment availability on river shorelines. Such variability in dry season duration was potentially mediated by the mean latitude of the ITCZ. The cessation of most dune accretion after ca. 10 ka suggests reduced seasonality and a more northerly ITCZ position, consistent with evidence from the Cariaco Basin.

  2. Cusiana trend exploration, Llanos Foothills thrustbelt, Colombia: The opening of a new hydrocarbon province

    SciTech Connect

    O`Leary, J.; Hayward, T.; Addison, F.; Espinosa, G.

    1996-12-31

    The Llanos Foothills petroleum trend of the Eastern Cordillera in Colombia containing the giant Cusiana Field has proven to be one of the most exciting hydrocarbon provinces discovered in recent years. The Llanos Foothills trend is a fold and thrust belt with cumulative discovered reserves to date of nearly 6 billion barrels of oil equivalent. This paper summarizes the critical exploration techniques used in unlocking the potential of this major petroleum system. The first phase of exploration in the Llanos Foothills lasted from the early 1960`s to the mid-70`s. Several large structures defined by surface geology and seismic data were drilled. Although no major discoveries were made, evidence of a petroleum play was found. The seismic imaging and drilling technology combined with the geological understanding which was then available did not allow the full potential of the trend to be realized. In the late 1980`s better data and a revised geological perception of the trend led BP, Triton and Total into active exploration, which resulted in the discovery of the Cusiana Field. The subsequent discovery of the Cupiagua, Volcanera, Florena and Pauto Sur Fields confirmed the trend as a major hydrocarbon province. The exploration programme has used a series of geological and geophysical practices and techniques which have allowed the successful exploitation of the trend. The critical success factor has been the correct application of technology in seismic acquisition and recessing and drilling techniques.

  3. Cusiana trend exploration, Llanos Foothills thrustbelt, Colombia: The opening of a new hydrocarbon province

    SciTech Connect

    O'Leary, J.; Hayward, T.; Addison, F. ); Espinosa, G. )

    1996-01-01

    The Llanos Foothills petroleum trend of the Eastern Cordillera in Colombia containing the giant Cusiana Field has proven to be one of the most exciting hydrocarbon provinces discovered in recent years. The Llanos Foothills trend is a fold and thrust belt with cumulative discovered reserves to date of nearly 6 billion barrels of oil equivalent. This paper summarizes the critical exploration techniques used in unlocking the potential of this major petroleum system. The first phase of exploration in the Llanos Foothills lasted from the early 1960's to the mid-70's. Several large structures defined by surface geology and seismic data were drilled. Although no major discoveries were made, evidence of a petroleum play was found. The seismic imaging and drilling technology combined with the geological understanding which was then available did not allow the full potential of the trend to be realized. In the late 1980's better data and a revised geological perception of the trend led BP, Triton and Total into active exploration, which resulted in the discovery of the Cusiana Field. The subsequent discovery of the Cupiagua, Volcanera, Florena and Pauto Sur Fields confirmed the trend as a major hydrocarbon province. The exploration programme has used a series of geological and geophysical practices and techniques which have allowed the successful exploitation of the trend. The critical success factor has been the correct application of technology in seismic acquisition and recessing and drilling techniques.

  4. Silurian of central Texas: a first record for the region.

    PubMed

    Barnes, V E; Boucot, A J; Cloud, P E; Miller, R H; Palmer, A R

    1966-11-25

    Silurian outcrops, not previously recorded from central Texas, have been identified from the Llano uplift, where they occur in collapse structures within the Lower Ordovician Honeycut Formation of the Ellenburger Group. The formation is a pinkish-gray granular limestone, contains fossils of probable Wenlock age, and is named the Starcke Limestone.

  5. Cusiana trend exploration, Llanos foothills thrustbelt Colombia - the opening of a new hydrocarbon province

    SciTech Connect

    Hayward, A.B.; Addison, F.T.; Espinosa, G.

    1995-08-01

    The Cusiana discovery in 1991 followed 30 years of exploration in the Llanos foothills. Wells drilled in the early 1960`s on large surface anticlines encountered residual oil accumulations in structures that had been flushed by along strike exposure of the major reservoir horizons. A second period of exploration activity in the early 1970`s failed through a consequence of drilling technology and seismic data quality. The Cusiana 2A well completed at the end of 1991 proved the existence of a 1500` hydrocarbon column in a structure 25 km long and 5-6 k across. Reserves in Cusiana are estimated at 1.5 BN BBLS and several TCF of gas. The Cusiana discovery opened the way for a concentrated exploration effort in the Llanos foothills. The subsequent Cupiagua discovery (500 mmstb) made in 1993 and the Volcanera discovery (5TCF, 250 mmstb) in 1994 have demonstrated the continuation of the trend northwards. Within the trend there are two discrete structural trapping geometries. Cusiana and Volcanera are thick-skinned basement involved structures related to the late Miocene reactivation of pre-existing Cretaceous extensional faults. The Cupiagua structural trend is a series of thin-skinned thrust sheets that have been displaced up to 10 km from the west. Key to successful exploration has been effective imaging of hydrocarbon trapping geometries brought about through a significant improvement in seismic acquisition and processing technology.

  6. Llano Grande Center's Oral History Project Sparks Cultural and Economic Renewal in Texas's Rio Grande Valley. Rural Trust Featured Project.

    ERIC Educational Resources Information Center

    Null, Elizabeth Higgins

    The Llano Grande Center for Research and Development started as an oral history experiment in two of Texas's poorest school districts. Since the 1920s, when this arid region in the southernmost tip of Texas was first transformed into the orchards and farmlands of the "Magic Valley," workers of Mexican descent have worked the land. Over…

  7. Overview of some biomedical research projects in tropical medicine conducted at the Instituto Venezolano de Investigaciones Cientificas.

    PubMed

    Romano, E; Cesari, I; Escalante, A; Liprandi, F; O'Daly, J A; Perez, H; Takiff, H

    2000-01-01

    The Instituto Venezolano de Investigaciones Cientificas (IVIC) is a government-funded multidisciplinary academic institution dedicated to research, development and technology in many areas of knowledge. Biomedical projects and publications comprise about 40% of the total at IVIC. In this article, we present an overview of some selected research and development projects conducted at IVIC which we believe contain new and important aspects related to malaria, ancylostomiasis, dengue fever, leishmaniasis and tuberculosis. Other projects considered of interest in the general area of tropical medicine are briefly described. This article was prepared as a small contribution to honor and commemorate the centenary of the Instituto Oswaldo Cruz.

  8. Basin development and tectonic history of the Llanos Basin, Eastern Cordillera, and Middle Magdalena Valley, Colombia

    SciTech Connect

    Cooper, M.A.; Addison, F.T.; Alvarez, R.

    1995-10-01

    The Middle Magdalena Valley, Eastern Cordillera, and Llanos basin constituted a major regional sedimentary basin from the Triassic to the middle Miocene. Basin development began during the Triassic to the earliest Cretaceous with a synrift megasequence related to the separation of North and South America in the proto-Caribbean. The synrift megasequence began with deposition in a continental environment that became paralic and shallow marine in the Early Cretaceous. Basin development continued into the Cretaceous in a back-arc setting east of the Andean subduction zone. The back-arc megasequence was dominated by shallow-marine sedimentation and produced an excellent regional source rock during the Turonian-Coniacian. Marine deposition was abruptly terminated during the early Maastrichtian due to the final accretion of the Western Cordillera.

  9. [Spatial-Temporal variability of aquatic plant communities in the Venezuelan Llanos].

    PubMed

    Rial B, Anabel

    2006-06-01

    The richness and abundance of aquatic plant communities were studied in 14 habitats of the Venezuelan "llanos" (07 degrees 35'-07 degrees 55' N-68 degrees 50'-69 degrees 00' W, Apure) during an annual cycle. Annual means were 27 degrees C, 115 mm rainfall and 77% relative humidity. A permanent transect was set in each habitat (ten consecutive square meter quadrats from the shore to the water). The plants and the area they covered in each quadrat were recorded monthly for a year. The total richness was 69 species. Alatalo and Alatalo's diversity analysis indicates that season, and its correlate, water level, influence species diversity and abundance more than habitat (spatial factor: geometric index-Euclidean distance).

  10. Infestation of rural houses by Triatoma infestans in the region of Los Llanos (La Rioja, Argentina).

    PubMed

    Porcasi, X; Hrellac, H; Catalá, S; Moreno, M; Abrahan, L; Hernandez, L; Gorla, D E

    2007-02-01

    Vectorial transmission of Chagas disease has been strongly reduced in most parts of the Southern Cone countries of South America, except in the Gran Chaco region of Argentina, Bolivia, and Paraguay. Given periodical interruptions of the vector control programmes in the endemic region of the Gran Chaco of Argentina, the vectorial transmission of the disease has been increasing during the last years. From the beginning of 2004, the provincial Ministry of Health of La Rioja, Argentina, started a vector control programme to cover the rural houses of the Los Llanos area in the southwestern area of the Gran Chaco region. This article reports the result of a standardized entomological survey and insecticide application against Chagas disease vectors in the intra and peridomestic structures of the rural houses of Los Llanos. A total of 4062 houses were inspected, of which 46.8% were found to be infested by Triatoma infestans. Infestation by vector species other than T. infestans was less than 0.5%(T. eratyrusiformis and T. platensis). Intradomestic infestation was found in 27.2%, whereas peridomestic infestation was found in 39.3% of the houses. The lowest figure of intradomestic infestation was 6.6% (Department F Varela), and the highest value of intradomestic infestation was 45.1% (Department Independencia). In spite of the demonstrated success of vector control elsewhere, this study shows that the vector populations are susceptible to pyrethroid insecticides in the southern area of the Gran Chaco of Argentina, that there still are regions where rural houses show heavy infestation by T. infestans associated with big peridomestic structures and that the vectorial transmission of the Chagas disease will continue, unless a sustained and well organized vector control effort is installed in the region.

  11. Raised fields in the Llanos de Moxos, Bolivia - description and analysis of their morphology

    NASA Astrophysics Data System (ADS)

    Rodrigues, Leonor; Lombardo, Umberto; Veit, Heinz

    2014-05-01

    The disturbance of Pre Columbian populations on Amazonian ecosystems is being actively debated. The traditional view of amazon being an untouched landscape because of its poor soils and harsh climate has been challenged and the extreme opposite idea of highly modified landscapes with complex societies is growing. Recent research has led to new impulses and issues requesting about the agricultural strategies people developed to survive in this climate. The Llanos de Moxos, situated in the Bolivian Lowlands in south-eastern Amazonia is one important region which was densely altered and where a great variety of earthworks can be found. One of the most impressive earth works are the raised fields, which are earth platforms for cultivation of differing shape and dimension that are elevated above the landscapes natural surface. In contrast to the "terra preta" formation where artefacts and amendments like charcoal and kitchen waste have been clearly identified, raised fields have shown to be artefact poor and studies up till now couldn't find any evidence of additional amendments which could have improved soil quality in the long term. As a result the function and productivity of raised fields is still not well understood and is being actively discussed. Detailed investigations on raised fields located in the indigenous community of Bermeo, in the vicinity of San Ignacio de Moxos provides data showing a novel explanation of the Pre-Columbian management of raised fields, and a chronological sequence of their utilization and abandonment. OSL dating has shown that the raised fields had been in use since as early as 600 AD. Comparison of Geochemistry with a reference profile, away from raised fields, showed that there is no evidence for manure amendments deriving from kitchen waste or animal residues suggesting a rather extensive use of those fields. Complementary the description of intern morphology and laboratory analysis of this raised fields, combined with radiocarbon

  12. Evaluation and management of vertically drained reservoirs: Castilla and Chichimene fields, Llanos Basin, Colombia

    SciTech Connect

    Hartshorn, K.G.

    1996-08-01

    The Castilla and Chichimene NE fields, operated by Chevron, are located in the southern Llanos basin of Colombia. The Castilla field, with an estimated 2.3 billion BBLS OOIP, produces heavy 14{prime} API oil, while the Chichimene NE field with an estimated 480 MMBBLS OOIP, produces a lighter 20{prime} API oil. Production is from multiple sandstone reservoirs of the Tertiary San Fernando and the Cretaceous Guadalupe Formations, and from massive non-marine sands of the Cretaceous Une Formation. Early problems with water coning and high water cuts led to detailed geologic study and engineering simulation to determine the most effective methods of reservoir management. The fresh nature of the connate water made evaluation more complicated, but results of RST (Reservoir Saturation Tool) logging runs on producing wells support the conclusions of the simulation studies regarding the potential for vertical drainage of the reservoir. As a result, the massive sands of the Une Formation can be perforated in the upper portion of the reservoir only, still enabling effective drainage of the lower reservoir while reducing water production and coning problems.

  13. Fluorescence microspectrography of zircon and apatite in Llano Uplift rocks, Texas

    SciTech Connect

    Goebel, V.W. . Dept. of Geology)

    1993-02-01

    Fluorescence investigations of common minerals under the microscope yield valuable mineralogic and petrologic information. They are best carried out in incident fluorescence light using polished sections of the sample materials which allows both qualitative and quantitative characterization. Results are complementary to traditional polarization optical and cathodoluminescence examinations. Observations of high light intensity grain colors, color variations, and distribution patterns may be made at total magnifications as high as 1,000x revealing details of luminophor distribution, fabric and growth patterns. Quantitative spectral analyses of fluorescence colors are for zircon and apatite grains from mostly granitic, Middle Proterozoic rocks of the Llano Uplift using a LEITZ MPV-SP spectrophotometer. Color analyses and color norm calculations were done with the SPECTRA computer program. Photo excitation (wave lengths 340--490 nm) produced characteristic fluorescence spectral for the recorded wave length range of 500--750 nm showing distinct differences between zircon and apatite, within each mineral population, and between rock types. Characteristic peaks correlate with the REE contents. Quantitative color plots on the CIE (1931) norm color diagram indicate for zircon saturated yellow-green colors between 550 and 575 nm and saturated yellow colors (575--585 nm) for apatite illustrating the possibility of a meaningful, quantitative fluorescence color characterization.

  14. Atmospheric stability and diurnal patterns of aeolian saltation on the Llano Estacado

    NASA Astrophysics Data System (ADS)

    Lanigan, David; Stout, John; Anderson, William

    2016-06-01

    Aeolian transport is driven by aerodynamic surface stress imposed by turbulent winds in the Earth's atmospheric boundary layer (ABL). ABL regime is influenced by stratification, which can either enhance or suppress production of turbulence by shear associated with the vertical gradient of streamwise velocity. During the day and night, surface heat fluxes induce a negative (unstable) and positive (stable) vertical gradient of potential temperature, respectively, which modifies the role of buoyancy in turbulence production. During the brief morning and evening transition periods, the vertical gradient of potential temperature vanishes (neutral stratification). The Monin-Obukhov similarity theory describes how the vertical gradient of streamwise velocity varies with stratification. Simultaneous field measurement of wind speed and aeolian activity were obtained over a 218-day period on a bare, sandy surface on the high plains of the Llano Estacado region of west Texas. Wind speed was measured at a height of 2 m with a propeller-type anemometer and aeolian activity was measured at the surface with a piezoelectric saltation sensor. We have used the wind speed measurements within the framework of the Monin-Obukhov similarity theory to estimate "typical" shear velocity, u∗ , of the ABL as stratification is varied (characterized with the stability parameter). This approach results in a color flood contour of u∗ against time of day and stability parameter: the procedure demonstrates that aeolian activity is most likely to occur during the day, when buoyancy acts in conjunction with mechanical shear to increase u∗ .

  15. Prevalence and characterization of influenza viruses in diverse species in Los Llanos, Colombia

    PubMed Central

    Karlsson, Erik A; Ciuoderis, Karl; Freiden, Pamela J; Seufzer, Bradley; Jones, Jeremy C; Johnson, Jordan; Parra, Rocio; Gongora, Agustin; Cardenas, Dario; Barajas, Diana; Osorio, Jorge E; Schultz-Cherry, Stacey

    2013-01-01

    While much is known about the prevalence of influenza viruses in North America and Eurasia, their prevalence in birds and mammals in South America is largely unknown. To fill this knowledge gap and provide a baseline for future ecology and epidemiology studies, we conducted 2 years of influenza surveillance in the eastern plains (Los Llanos) region of Colombia. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) identified influenza viruses in wild birds, domestic poultry, swine and horses. Prevalence ranged from 2.6% to 13.4% across species. Swine showed the highest prevalence and were infected primarily with 2009 pandemic H1N1 (pH1N1) viruses genetically related to those in humans. In addition, we isolated H5N2 viruses from two resident species of whistling ducks (genus Dendrocygna) that differed completely from previous South American isolates, instead genetically resembling North American wild bird viruses. Both strains caused low pathogenicity in chickens and mammals. The prevalence and subtype diversity of influenza viruses isolated from diverse species within a small area of Colombia highlights the need for enhanced surveillance throughout South America, including monitoring of the potential transmissibility of low-pathogenic H5N2 viruses from wild birds to domestic poultry and the emergence of reassortant viruses in domestic swine. PMID:26038461

  16. Prevalence and characterization of influenza viruses in diverse species in Los Llanos, Colombia.

    PubMed

    Karlsson, Erik A; Ciuoderis, Karl; Freiden, Pamela J; Seufzer, Bradley; Jones, Jeremy C; Johnson, Jordan; Parra, Rocio; Gongora, Agustin; Cardenas, Dario; Barajas, Diana; Osorio, Jorge E; Schultz-Cherry, Stacey

    2013-04-01

    While much is known about the prevalence of influenza viruses in North America and Eurasia, their prevalence in birds and mammals in South America is largely unknown. To fill this knowledge gap and provide a baseline for future ecology and epidemiology studies, we conducted 2 years of influenza surveillance in the eastern plains (Los Llanos) region of Colombia. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) identified influenza viruses in wild birds, domestic poultry, swine and horses. Prevalence ranged from 2.6% to 13.4% across species. Swine showed the highest prevalence and were infected primarily with 2009 pandemic H1N1 (pH1N1) viruses genetically related to those in humans. In addition, we isolated H5N2 viruses from two resident species of whistling ducks (genus Dendrocygna) that differed completely from previous South American isolates, instead genetically resembling North American wild bird viruses. Both strains caused low pathogenicity in chickens and mammals. The prevalence and subtype diversity of influenza viruses isolated from diverse species within a small area of Colombia highlights the need for enhanced surveillance throughout South America, including monitoring of the potential transmissibility of low-pathogenic H5N2 viruses from wild birds to domestic poultry and the emergence of reassortant viruses in domestic swine.

  17. Metabasalts and metagabbros from the Llano Uplift, Texas: Petrologic and geochemical characterization with emphasis on tectonic setting

    NASA Astrophysics Data System (ADS)

    Garrison, James R.

    1982-03-01

    The 1.0-1.2 b.y. old rocks of the southeastern Llano Uplift, Texas include a 7 km thick sequence of amphibolite-grade, stratified, mafic metasedimentary rock (Packsaddle Schist) which is intruded by a varied suite of syntectonic and late-kinematic intrusions. The metasediments contain large blocks of serpentinized peridotite (Coal Creek serpentinite) and coarse hornblendite and metagabbro. Prior to the end of maximum deformation, the sequence was intruded by low to medium-K2O tholeiitic basalts (0.40-0.72% K2O). Late-kinematic low-K2O tholeiitic basalts (0.38-0.40% K2O) were intruded as dikes into the folded rocks. The Coal Creek serpentinite contains both syntectonic and late-kinematic low-K2O tholeiitic metabasalts (0.13 0.36% K2O). The Llano metabasalts and metagabbros are characterized by low Cr (67 378 ppm) and Ni (36 170 ppm), variable Rb (1.5 14.7 ppm), Sr (140 1229 ppm), TiO2 (0.40 2.20%), P (568 2707 ppm), and Zr (18 230 ppm), and Y (16 45 ppm), Co (40 57 ppm), and Sc (36 49 ppm) similar to modern MORB. The metabasalts have La abundances from 7 to 39 times chondritic and exhibit light REE enrichment with ¦La/Sm¦N from 1.13 to 1.45 and ¦La/Yb¦N from 1.12 to 2.99. The metabasalts show a strong correlation of increasing Zr, Ti, and Y and decreasing Eu/Eu* (1.56 1.00), CaO/TiO2, Al2O3/TiO2, and MgO/ MgO+FeO* with increasing REE enrichment (LaN). The Llano metabasalts and metagabbros have initial 87Sr/86Sr=0.7029±0.0001. A likely petrogenetic model for these metabasalts is an island arc in which events from early arc development to final late-kinematic intrusion were dominated by tholeiitic volcanism and intrusion. The chemical systematics of the Llano mafic metaigneous rocks suggest they are products of fractionation of olivine, clinopyroxene, and plagioclase from more primitive basaltic magmas generated beneath the island arc complex.

  18. Reservoir performance of Late Eocene incised valley fills, Cusiana Field, Llanos Foothills, Eastern Colombia

    SciTech Connect

    Pulham, A. ); Edward, W. ); App, J. )

    1996-01-01

    The Cusiana Field is located in the Llanos Foothills of Eastern Colombia. The principal reservoir is the late Eocene Mirador Formation which comprises >50% of reserves. Currently the Mirador reservoir is providing nearly all of the 150,00bopd of production from the Cusiana Field. The Mirador reservoir comprises a stack of incised valley deposits. The fills of the valleys are dominated by quartz arenite sandstones. The average porosity of the valley sandstones is 8% which reflects abundant quartz cement ([approximately]14%) and significant compaction during deep burial ([approximately]20,000feet). Single valleys are up to 70 feet thick and exhibit a distinctive bipartite fill that reflects changing energy conditions during filling. Bases of valleys have the coarsest grain size and have sedimentological and trace fossil evidence for deposition in highly stressed, brackish water environments. The upper parts of the valleys are typically finer grained and were deposited in more saline settings. Despite the low porosity of the Mirador valleys, drill stem tests and production log data show that they have phenomenal performance characteristics. Rates of [ge]10,000bopd are achieved from single valleys. Bases of the valley fills are the key contributors to flow. Integration of detailed core and pore system analysis with the reservoir performance data shows that the permeability fabric of the Mirador can be explained by original depositional architecture and simple loss of primary porosity. Comparison of Cusiana with other quartz-rich sandstones from around the world suggests that it's low porosity/high performance is predictable.

  19. Cusiana trend exploration, Llanos foothills, Colombia - The opening of a new hydrocarbon province

    SciTech Connect

    Hayward, A.B.; Addison, F.T.; O`Leary, J.; Espinosa, C.

    1996-08-01

    The discovery of the Cusiana field in 1992 followed 30 years of exploration in the Llanos fold and thrust belt of Colombia. Early exploration activity focused on large surface anticlines that were all fresh water flushed - a consequence of along strike exposure of the reservoir rocks. The potential for deeper, subthrust, trapping geometries was recognized in the early 1970s however, exploration at the time was hindered by very poor quality seismic data and significant drilling difficulties. The 1980s exploration effort was characterized by continued poor quality seismic data and drilling difficulties combined with a geological perception that there was no effective reservoir and the majority of the structures post dated the major period of hydrocarbon generation and migration. The Cusiana discovery with a gross hydrocarbon column in excess of 1500{prime} reservoired within the Mirador (Eocene), Barco (Palaeocene) and Guadalupe (Upper Cretaceous) Formations in a large thrust anticline demonstrated the presence of a working hydrocarbon system. Subsequent exploration of the trend to the north has resulted in the discovery of four further giant oil and gas fields, Cupiagua (500 MMBBLs, 1-2 tcf) and the Florena/Pauto/Volcanera complex with estimated reserves of 1 billion barrels and 10 tcf. Key to this success has been the seismic imaging of the trapping geometries resulting from a significant improvement in the quality of the seismic data - a consequence of improvements in both acquisition and processing technology, combined with a recognition that pure quartz arenites retain reservoir quality at significant depths of burial-and that despite original depths of burial of greater than 18,000 ft, reservoir quality was not a major risk for further exploration success.

  20. Reservoir performance of Late Eocene incised valley fills, Cusiana Field, Llanos Foothills, Eastern Colombia

    SciTech Connect

    Pulham, A.; Edward, W.; App, J.

    1996-12-31

    The Cusiana Field is located in the Llanos Foothills of Eastern Colombia. The principal reservoir is the late Eocene Mirador Formation which comprises >50% of reserves. Currently the Mirador reservoir is providing nearly all of the 150,00bopd of production from the Cusiana Field. The Mirador reservoir comprises a stack of incised valley deposits. The fills of the valleys are dominated by quartz arenite sandstones. The average porosity of the valley sandstones is 8% which reflects abundant quartz cement ({approximately}14%) and significant compaction during deep burial ({approximately}20,000feet). Single valleys are up to 70 feet thick and exhibit a distinctive bipartite fill that reflects changing energy conditions during filling. Bases of valleys have the coarsest grain size and have sedimentological and trace fossil evidence for deposition in highly stressed, brackish water environments. The upper parts of the valleys are typically finer grained and were deposited in more saline settings. Despite the low porosity of the Mirador valleys, drill stem tests and production log data show that they have phenomenal performance characteristics. Rates of {ge}10,000bopd are achieved from single valleys. Bases of the valley fills are the key contributors to flow. Integration of detailed core and pore system analysis with the reservoir performance data shows that the permeability fabric of the Mirador can be explained by original depositional architecture and simple loss of primary porosity. Comparison of Cusiana with other quartz-rich sandstones from around the world suggests that it`s low porosity/high performance is predictable.

  1. Biomarkers and compound-specific stable carbon isotope of n-alkanes in crude oils from Eastern Llanos Basin, Colombia

    NASA Astrophysics Data System (ADS)

    Cortes, Jorge E.; Rincon, Jose M.; Jaramillo, Jose M.; Philp, R. Paul; Allen, Jon

    2010-03-01

    Representative samples of crude oils from Cusiana, Cupiagua, Apiay, Castilla and Chichimene fields in the Eastern Llanos Basin of Colombia were analyzed to determine its compound-specific stable carbon isotope composition (CSIA) using gas chromatography-isotopic ratio-mass spectrometry (GC-IRMS). GC-IRMS analyses of n-alkanes allowed differentiating between Cretaceous and Cretaceous/Tertiary oil samples. Cretaceous sourced samples have δ13C-enriched values than Cretaceous/Tertiary sourced samples; the heavier isotope composition of these samples is due to their major terrigenous organic matter input. Their isotope distribution patterns suggest significant algal and/or bacterial contribution (marine origin). The analysis of the n-alkane fractions by GC-IRMS confirms that the organic matter has marine origin in those samples from Cusiana, Cupiagua and Apiay while Castilla and Chichimene have marine origin with terrestrial inputs. The results were confirmed by gas chromatography/FID and gas chromatography/mass spectrometry (GC/MS). Basic geochemical composition show that samples from Cupiagua/Cusiana fields and Apiay/Castilla/Chichimene fields in the Llanos basin, Colombia present different characteristics reflecting a specific for each depositional environment.

  2. East with the Night: Longitudinal Migration of the Orinoco Goose (Neochen jubata) between Manú National Park, Peru and the Llanos de Moxos, Bolivia

    PubMed Central

    Davenport, Lisa C.; Nole Bazán, Inés; Carlos Erazo, Nancy

    2012-01-01

    We report on the intra-Amazonian migration of a pair of Orinoco Geese (Neochen jubata) from Manú National Park, Peru. The species is Critically Endangered in Peru, so a major aim of the study was to aid conservation planning by learning the wet season location of the country's last known breeding population. We captured a breeding pair on October 27, 2010, and fitted the birds with Microwave Telemetry, Inc. GPS/Argos satellite PTT's. The pair migrated ∼655 km from Manú National Park to the Llanos de Moxos, Bolivia (Dept. of Bení) in a predominantly longitudinal migration, reaching their final destination on December 23, 2010. Major movements (>5 km per time period) were almost exclusively at night and were undertaken with and without moonlight. Foraging areas used at stopovers in the Llanos de Moxos were remarkably limited, suggesting the importance of grazing lawns maintained by the geese and other herbivores, possibly including cattle. Orinoco Geese are resident in the Llanos de Moxos year-round, so the Manú geese represent a partial migration from the Bení region. We hypothesize that cavity nest limitation explains the partial migration of Orinoco Geese from the Llanos de Moxos. PMID:23056512

  3. East with the night: longitudinal migration of the Orinoco goose (Neochen jubata) between Manú National Park, Peru and the Llanos de Moxos, Bolivia.

    PubMed

    Davenport, Lisa C; Nole Bazán, Inés; Carlos Erazo, Nancy

    2012-01-01

    We report on the intra-Amazonian migration of a pair of Orinoco Geese (Neochen jubata) from Manú National Park, Peru. The species is Critically Endangered in Peru, so a major aim of the study was to aid conservation planning by learning the wet season location of the country's last known breeding population. We captured a breeding pair on October 27, 2010, and fitted the birds with Microwave Telemetry, Inc. GPS/Argos satellite PTT's. The pair migrated ∼655 km from Manú National Park to the Llanos de Moxos, Bolivia (Dept. of Bení) in a predominantly longitudinal migration, reaching their final destination on December 23, 2010. Major movements (>5 km per time period) were almost exclusively at night and were undertaken with and without moonlight. Foraging areas used at stopovers in the Llanos de Moxos were remarkably limited, suggesting the importance of grazing lawns maintained by the geese and other herbivores, possibly including cattle. Orinoco Geese are resident in the Llanos de Moxos year-round, so the Manú geese represent a partial migration from the Bení region. We hypothesize that cavity nest limitation explains the partial migration of Orinoco Geese from the Llanos de Moxos.

  4. Multiobjective optimization for Groundwater Nitrate Pollution Control. Application to El Salobral-Los Llanos aquifer (Spain).

    NASA Astrophysics Data System (ADS)

    Llopis-Albert, C.; Peña-Haro, S.; Pulido-Velazquez, M.; Molina, J.

    2012-04-01

    Water quality management is complex due to the inter-relations between socio-political, environmental and economic constraints and objectives. In order to choose an appropriate policy to reduce nitrate pollution in groundwater it is necessary to consider different objectives, often in conflict. In this paper, a hydro-economic modeling framework, based on a non-linear optimization(CONOPT) technique, which embeds simulation of groundwater mass transport through concentration response matrices, is used to study optimal policies for groundwater nitrate pollution control under different objectives and constraints. Three objectives were considered: recovery time (for meeting the environmental standards, as required by the EU Water Framework Directive and Groundwater Directive), maximum nitrate concentration in groundwater, and net benefits in agriculture. Another criterion was added: the reliability of meeting the nitrate concentration standards. The approach allows deriving the trade-offs between the reliability of meeting the standard, the net benefits from agricultural production and the recovery time. Two different policies were considered: spatially distributed fertilizer standards or quotas (obtained through multi-objective optimization) and fertilizer prices. The multi-objective analysis allows to compare the achievement of the different policies, Pareto fronts (or efficiency frontiers) and tradeoffs for the set of mutually conflicting objectives. The constraint method is applied to generate the set of non-dominated solutions. The multi-objective framework can be used to design groundwater management policies taking into consideration different stakeholders' interests (e.g., policy makers, agricultures or environmental groups). The methodology was applied to the El Salobral-Los Llanos aquifer in Spain. Over the past 30 years the area has undertaken a significant socioeconomic development, mainly due to the intensive groundwater use for irrigated crops, which has

  5. Reworked pre-Grenville crust and timing of Grenville orogenesis in the southeastern Llano Uplift, Texas: Results from U-Pb geochronometry

    SciTech Connect

    Reese, J.F.; Roback, R.C.; Walker, N.W. . Geological Sciences)

    1992-01-01

    Zircon geochronometry of metaigneous units in the southeastern Llano Uplift (1) show that 1355-1215 Ma rocks were tectonically reworked during the Grenville orogeny, (2) further constrain the timing of Grenville orogenesis along the southern margin of North America, and (3) necessitate revision of previously proposed stratigraphic and structural relations within the Llano Supergroup. Multigrain, abraded zircon fractions from a sample of quartzofeldspathic Valley Spring Gneiss (VSG) define a discordia trajectory with an upper intercept of 1355 [plus minus] 3 Ma, interpreted as the igneous crystallization age of the protolith. This age is the oldest thus far documented for Llano Supergroup protoliths and is substantially older than a recently reported age (1232 [plus minus]4 Ma) from a different part of the VSG. The lithologic and chronometric similarities of the old VSG to rocks to the Mid-continent Granite-Rhyolite terrane raise the possibility of genetic relations between these units. Thus components of the VSG are tentatively interpreted to represent a deformed and metamorphosed part of the southernmost Mid-Continent Granite-Rhyolite terrane. Alternatively, this rock could be part of an ensialic arc built upon the margin of southern North America and later deformed during the Grenville orogeny. Analyses from four abraded zircon fractions from a quartzofeldspathic gneiss in the structurally overlying Packsaddle Schist yield an upper intercept of 1215 [plus minus] 3 Ma, interpreted as the igneous protolith crystallization age. This age is the youngest yet determined for a polydeformed metamorphic rock in the Llano Uplift and more tightly brackets the timing of Grenville deformation in the southeastern Llano Uplift to post-1215 Ma and pre-1098 Ma.

  6. Survey of trace metals in drinking water supplied to rural populations in the eastern Llanos of Venezuela.

    PubMed

    Mora, Abrahan; Mac-Quhae, César; Calzadilla, Malvis; Sánchez, Luzmila

    2009-02-01

    To ascertain the water quality for human consumption, chemical parameters such as pH, conductivity and total dissolved calcium, magnesium, iron, aluminum, zinc, copper and manganese were measured during four sampling periods (November 2002; March, May and July 2003) in drinking water wells which supply several forest camps and rural populations located in the eastern Llanos of Venezuela. Copper levels in drinking water in November 2002 were found to be significantly higher (P<0.05) than the other assessed periods. Temporal variations of the other parameters considered were not statistically significant. Calcium and magnesium concentrations were found to be extremely low (mean concentration+/-S.D. of 0.27+/-0.25mg/l for Ca and 0.219+/-0.118 for Mg) during the four sampling periods, probably because of the carbonate bearing scarcity in the soils lithic component. The rest of the metals complied with the Venezuelan and International guidelines of quality criteria for drinking water.

  7. Molecular organic geochemistry of the Apiay field in the Llanos basin, Colombia

    NASA Astrophysics Data System (ADS)

    Cortes, J. E.; Niño, J. E.; Polo, J. A.; Tobo, A. G.; Gonzalez, C.; Siachoque, S. C.

    2013-11-01

    The bulk properties and molecular organic geochemical composition for crude oils from the Apiay, Suria and Reforma/Libertad producer areas, which integrate the Apiay field located in the southwest area of the Llanos Basin in Colombia were analyzed by gas chromatography (GC/FID), isotopic analysis and gas chromatography/mass spectrometry (GC/MS) analysis. The main producing intervals in the Apiay field are known as the K2 and K1 units of the Guadalupe Formation, a thick siliciclastic sequence deposited during the Upper Cretaceous to Upper Eocene in a fluvial and transitional marine system. The crude oils analyzed are paraffinic, with saturate fraction >60%, the δ13C isotopic composition ranging from -26.19 to -25.62 for the saturated fraction, -25.84 to -24.02 for the aromatic fraction, and canonical variable (C.V.) <0.47, which characterized them as non-waxy marine oils. The saturated fraction analyzed by GC/FID presents a unimodal distribution between n-C10 to n-C33 with n-C15 to n-C17 as the major peaks. CPI is close or slightly greater than 1.0, Pr/Ph ratio >1.5, low ≈ high molecular weigh hydrocarbons indicating an input of algal/microbial organic matter with a significant input of terrigenous matter (higher plants). Branched/Cyclic biomarkers, previously separated from n-alkanes by silicalite/ZSM-5 (S-115), were analyzed using SIM-GC/MS. Samples from the Apiay area showed higher concentration of tricyclic terpanes than samples from Suria and Reforma-Libertad, respectively, which suggests an early diagenetic influence of marine saline water, consistent with early generation from marine organic matter. However, the presence of a great suit of sesquiterpanes and diterpanes in all samples confirming an angiosperm input. Ts/Ts + Tm falls in the range of 0.25-0.66, all samples present gammacerane, C31-Hopane isomerization index ranged between 0.50 and 0.71. A predominance of C29 over C27 and C28-steranes in the Apiay area indicates terrigenous source rock for

  8. From 'true' glaciers to rock glaciers? The case of the Llanos la Liebre rock glacier, dry Andes of Chile.

    NASA Astrophysics Data System (ADS)

    Monnier, S.; Kinnard, C.

    2012-04-01

    In the dry Andes of Chile, rock glaciers are the most widespread and remarkable superficial landforms, and may constitute important solid water reservoirs. The existence of huge (up to 2-3 kilometres of length) rock glaciers located in deep cirques questions possible derivation from former 'true' glaciers. The issue is of importance (i) for understanding the mechanisms of the landscape evolution from glacial realm to periglacial realm, and (ii) because it may determine the ice content of the concerned rock glaciers. In the Colorado Río valley, in the upper part of the Elqui catchment (~30.15 deg. S and 70.80 deg. W), we investigated the internal structure of the Llanos la Liebre rock glacier using ground-penetrating radar (GPR). With 50 MHz antennas and a constant offset of 2 m between antennas, we performed various GPR profiles, especially a ~2.2 km-long one almost covering the entire length of the rock glacier. The processing and the subsequent interpretation of the GPR data were mainly based on the modelling of the radar wave velocity. Hence, the final representation of the internal structure of the rock glacier integrates the reconstructed stratigraphy, the 2-D velocity model, and first attempts for estimating the ice/water contents. The most striking results are: the neat identification of the base of the superficial blocky layer and of the rock glacier floor; the occurrence of stratigraphic patterns reminiscent of 'true' glaciers; the supremacy of high radar wave velocities in the upper part of the rock glacier. On the latter bases and taking into account the whole geomorphology of the site, the derivation of the Llanos la Liebre rock glacier from a former, buried glacier is debated.

  9. Implications of initial Pb isotopic ratios for source characteristics of Proterozoic rocks in the Llano Uplift and Trans-Pecos Texas

    SciTech Connect

    James, E.W. . Bureau of Economic Geology); Walker, N. . Dept. of Geological Sciences)

    1992-01-01

    Newly determined Pb isotopic ratios of HF acid-leached feldspars from Middle Proterozoic igneous and metaigneous rocks from the Llano Uplift and Trans-Pecos Texas suggest that these rocks are derived primarily from mantle of petrologically primitive crust. U-Pb geochronologic studies indicate pre-Grenville magmatism ranges in age from 1.35 to 1.23 Ga, whereas post-tectonic plutonism is 1.16 to 1.07 Ga. Initial Pb data from post-tectonic plutons plot along a 1.1 Ga 206-Pb/Pb-204--Pb-207/Pb-204 isochron, indicating that sources of these rocks have a range of U/Pb ratios or that radiogenic Pb was not entirely removed by leaching. Analyses from metaigneous rocks have a greater range. Several sequentially leached feldspars yield 1.1 Ga isochrons, suggesting that they incorporated radiogenic Pb during metamorphism. Initial ratios for the Texas rocks fall below the regional Pb-206/Pb-204--Pb-207/Pb-204 isochron for 1.7--1.4 Ga rocks of Arizona and New Mexico. At 1.35 to 1.1 Ga the isotopic ratios of these rocks would have been higher than the Texas initial ratios. This suggests that similar crust played, at most, a minor role in magmagenesis. In contrast, the Texas initial Pb ratios are within the range of ratios reported for the 1.5--1.3 Ga Granite-Rhyolite Province of the central US. Initial Pb isotopic ratios fall slightly below mantle model curves, and 1.3 to 1.1 Ga isochrons fitted to the data intersect these curves at 1.3 to 1.1 Ga model ages. The Pb-208/Pb-206 data for all samples suggest a source with Th/U [le] 4. The 1.35 to 1.23 Ga metaigneous samples appear to be derived from geochemically primitive sources, possibly in ensialic arc settings. Post-tectonic plutons may have similar juvenile sources but also could have assimilated or been derived from local 1.35 to 1.23 Ga crust.

  10. The effect of plate movements in the northern region of South America on tectonics and sedimentation in the Eastern Llanos Basin

    SciTech Connect

    Pena, L.E. )

    1993-02-01

    The geological configuration of the Eastern Llanos pericratonic mega-basin has been directly affected by the overall tectonic regime experienced in the Northern part of South America. Interaction between the Pacific (Cocos), South American and Caribbean Plates generated a regional compressional dextral rotational force expressed as a regional North-South striking structural trend in the southern part of the basin and an east-west striking trend in portion nearest the Caribbean Plate Boundary. Nearly 90% of the strike-slip faults in this northern area show right lateral displacement. The majority of the structures in the East Llanos basin are related to the Late Miocene uplift of the Eastern Andes. Nevertheless we can subdivide the structures into two major groups: pre-Miocene and post-Miocene. By being able to recognize pre-Miocene Cretaceous age structures, much altered by later movements, we can envision remigration of hydrocarbons out of early traps into those created more recently. Plate tectonic events in the north of South America have produced a general regional structure strike directional through time. Sedimentary-tectonic relationships depend upon regional phenomena which, if interpreted correctly, help to sub-divide the mega-basin into genetically related parts. By understanding the mechanism that creates large scale structural features, the geologist is thus provided with an important tool that can aid him in exploring the Eastern Llanos basin.

  11. Stress field estimation based on focal mechanisms and back projected imaging in the Eastern Llanos Basin (Colombia)

    NASA Astrophysics Data System (ADS)

    Gómez-Alba, Sebastián; Fajardo-Zarate, Carlos Eduardo; Vargas, Carlos Alberto

    2016-11-01

    At least 156 earthquakes (Mw 2.8-4.4) were detected in Puerto Gaitán, Colombia (Eastern Llanos Basin) between April 2013 and December 2014. Out of context, this figure is not surprising. However, from its inception in 1993, the Colombian National Seismological Network (CNSN) found no evidence of significant seismic events in this region. In this study, we used CNSN data to model the rupture front and orientation of the highest-energy events. For these earthquakes, we relied on a joint inversion method to estimate focal mechanisms and, in turn, determine the area's fault trends and stress tensor. While the stress tensor defines maximum stress with normal tendency, focal mechanisms generally represent normal faults with NW orientation, an orientation which lines up with the tracking rupture achieved via Back Projection Imaging for the study area. We ought to bear in mind that this anomalous earthquake activity has taken place within oil fields. In short, the present paper argues that, based on the spatiotemporal distribution of seismic events, hydrocarbon operations may induce the study area's seismicity.

  12. [Variation of the orchid bees community (Hymenoptera: Apidae) in three altered habitats of the Colombian "llano" piedmont].

    PubMed

    Parra-H, Alejandro; Nates-Parra, Guiomar

    2007-01-01

    Orchid bees subsist in vast tropical forest areas because they maintain close relationships with particular plant species in diverse micro-habitats. Based on the relationships among the environment and biological features (food preference, morphologic and ethologic diversity), it is possible to determine habitat quality using the euglossine array. This work proposes the use of this ecological information, in addition to diversity indices, for the evaluation of environmental quality. Fifteen localities in three landscape types (urban, rural and conserved) were sampled in the eastern llanos foothill (Meta, Colombia), between March and December of 2003 using entomological nets, and Cineol and Metil Salicylate as baits. Of the 26 species known to occur in the area, 17 were registered. Eulaema nigrita was the most frequent, while E. speciosa E. bombiformis, Euglossa magnipes, E. cybelia, E. heterosticta, E. singularis and Exaerete frontalis were mostly found in habitats rated "good to acceptable". The vegetation composition and proximity of forest fragments seem to favor some species in disturbed habitats. Relative diversity of bee body shapes and sizes is proportional to habitat quality.

  13. The Grenville orogeny in the Llano Uplift, Texas: A record of collision and contraction along the southern margin of North America

    SciTech Connect

    Reese, J.F. . Dept. of Geological Sciences)

    1993-02-01

    Precambrian metamorphic rocks in the SE Llano Uplift record NE-directed ductile thrusting and regional-scale polyphase folding. This deformation is in response to Grenville-age shortening and crustal thickening associated with the collision of a south-lying tectonic block with the southern margin of North America. In the SE Llano Uplift, the most intense and pervasive deformational event, D2, is characterized in the Packsaddle Schist (PS) and Valley Spring Gneiss (VSG) by SSE-plunging, NE-verging isoclinal folds (F2) with an associated SW-dipping axial planar metamorphic layering (S2), and SW-dipping mylonite zones with kinematic indicators showing top-to-the-NE motion. In the Red Mountain and augen-bearing Big Branch gneisses, D2 structures are SW-dipping mylonite zones parallel to S2, and a SW-plunging stretching lineation. Taken together, this suite of structures indicates tectonic transport was to the NE, perpendicular to the NW trending regional structural and metamorphic grain. D2 structures were reoriented by at least two later phases of folding. Timing of all ductile deformation in the SE Llano Uplift is constrained from post-1,215 Ma (deformed PS) to pre-1,098 Ma (undeformed melarhyolite dike). From south to north, metatonalitic, arc-derived Big Branch Gneiss ([approximately] 1,303 Ma) and older mafic schist country rock, previously interpreted as possible ophiolitic melange, structurally overlie much younger, lithologically heterogeneous PS units (1,248-1,215 Ma), previously considered as arc flank deposits. In turn, the PS has been tectonically emplaced above the predominantly felsic VSG (1,270-1,232 Ma). The presence of older zircons in the VSG, of similar age ([approximately]1360 Ma) to Western Granite-Rhyolite Terrane rocks to the north, suggests that the VSG formed in a settling proximal to North America.

  14. Fertilizer standards for controlling groundwater nitrate pollution from agriculture: El Salobral-Los Llanos case study, Spain

    NASA Astrophysics Data System (ADS)

    Peña-Haro, S.; Llopis-Albert, C.; Pulido-Velazquez, M.; Pulido-Velazquez, D.

    2010-10-01

    SummaryAlthough the legislation on groundwater quality targets pollutant concentration, the effects of measures on non-point source pollution control are often evaluated in terms of their emission reduction potential at the source, not on their capacity of reducing the pollutant concentration in groundwater. This paper applies a hydro-economic modelling framework to an aquifer, El Salobral-Los Llanos aquifer (Mancha Oriental, Spain), where nitrate concentrations higher than those allowed by the EU Water Framework Directive and Groundwater Directive are locally found due to the intense fertilizer use in irrigated crops. The approach allows defining the economically optimal allocation of spatially variable fertilizer standards in agricultural basins using a hydro-economic model that links the fertilizer application with groundwater nitrate concentration at different control sites while maximizing net economic benefits. The methodology incorporates results from agronomic simulations, groundwater flow and transport into a management framework that yields the fertilizer allocation that maximizes benefits in agriculture while meeting the environmental standards. The cost of applying fertilizer standards was estimated as the difference between the private net revenues from actual application and the scenarios generated considering the application of the standards. Furthermore, the cost of applying fertilizer standards was compared with the cost of taxing nitrogen fertilizers in order to reduce the fertilizer use to a level that the nitrate concentration in groundwater was below the limit. The results show the required reduction of fertilizer application in the different crop areas depending on its location with regards to the control sites, crop types and soil-plant conditions, groundwater flow and transport processes, time horizon for meeting the standards, and the cost of implementing such a policy (as forgone benefits). According to the results, a high fertilizer price

  15. Exploration for stratigraphic traps in a foreland basin using a sequence stratigraphic simulation: Examples from the Eocene/Oligocene of the Apure-Llanos basin, Venezuela

    SciTech Connect

    Reistroffer, J.; Levine, P.A.; Kendall, C.G. ); Finno, A. )

    1996-01-01

    Foreland basin depositional sequences provide a sensitive record of the interaction between tectonism, eustatic sea level fluctuations, and sedimentation rates. Interplay between these controlling factors creates sedimentary geometries which are unique to this tectonic setting and form excellent stratigraphic hydrocarbon traps. Incised valley fill deposits, [open quote]forced regression[close quote] deposits, and combination structure-stratigraphic traps are the predominant reservoir types. In an effort to extend our understanding of the development of these traps, the sequence stratigraphy of a regional seismic transact through the Apure-Llanos basin was simulated. From the Late Eocene through Oligocene, the Apure-Llanos basin was Characterized by multiple phases of compression and a southeast migrating depocenter. Sands of the Mirador and Carbonera formations, which onlap the Arauca Arch to the southeast, were shed from the Guyana craton and were Cannibalized from sediments along the deformation front to the northwest. These sands comprise the principal reservoirs in the study area. Shales of the Leon Formation, which act as a regional seal, were deposited during rapid flexural subsidence and eustatic sea level rise during the early Oligocene. The Arauca Arch acted as a focal mechanism for east and southeast migrating hydrocarbons. Simulation results predict an important stratigraphic pinchout of the Mirador Formation sands against the Arauca Arch, which correlates with the Arauca Reid in Colombia to the southwest. Also, modeling indicates that minimal Tertiary oil production In the La Victoria Field to the east is due to the lack of an adequate seal. Our results provide a conceptual model which predicts hydrocarbon reservoir and seal relationships in a foreland basin setting with limited data control.

  16. Floods in south-central Texas, June 1997

    USGS Publications Warehouse

    Raines, Timothy H.; Asquith, William H.; Brown, David S.

    1998-01-01

    Severe flooding in parts of 18 south-central Texas counties resulted from heavy rainfall during June 21-22, 1997. Of the 18 counties in the study area (fig. 1), all except Kimble, Gillespie, and Travis were declared Federal disaster areas. Kimble and Gillespie Counties were later declared eligible for disaster assistance. The majority of the property damage occurred along Cibolo Creek in Kendall and Guadalupe Counties, the Medina River in Bandera County, and the Llano River in Mason and Llano Counties (Jack Quarrels, Federal Emergency Management Agency, oral commun., 1997). The total property damage for which owners were eligible for disaster assistance was estimated to be $10.4 million (Jack Quarrels, written commun., 1997). Several rain gages and streamflow-gaging stations located in the 18-county area were available for the U.S. Geological Survey (USGS), in cooperation with the Federal Emergency Management Agency, to assess the magnitude and historical perspective of the flooding. This fact sheet summarizes maximum rainfall and streamflow and associated recurrence intervals for selected rain gages and streamflow-gaging stations (fig. 1) in the 18-county study area during June 21-23, 1997.

  17. Llano Grande Lake bottom sediments; a chronicle of water-quality changes in the Arroyo Colorado, South Texas, 1989-2001

    USGS Publications Warehouse

    Mahler, Barbara June; Van Metre, Peter C.

    2002-01-01

    The Arroyo Colorado, an ancient channel of the Rio Grande, extends 90 miles from Mission, Tex., to the Laguna Madre. The Arroyo Colorado flows through areas of intense agricultural cultivation and through important habitat for migrating birds and other wildlife, including several wildlife sanctuaries and refuges. The above-tidal segment of the Arroyo Colorado is included in the State of Texas 2000 Clean Water Act 303(d)1 list in part because of elevated concentrations of the hydrophobic legacy pollutants DDE (a DDT breakdown product), chlordane, and toxaphene in fish tissue. This report addresses three questions: Do legacy pollutants (organochlorine compounds, major and trace elements) occur in the Arroyo Colorado at present and at what concentrations?How has the occurrence of selected legacy pollutants in the Arroyo Colorado changed over time?Are current concentrations of legacy pollutants in bottom sediments at levels of concern for the health of aquatic biota?To answer these questions, the U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency (USEPA), collected and analyzed a sediment core from Llano Grande Lake on the Arroyo Colorado (fig. 1). Sediment cores can be used to reconstruct historical trends in concentrations of hydrophobic contaminants (Eisenreich and others, 1989; Van Metre and others, 1997, 2000). The lake is part of the Rio Grande delta drainage system (fig. 1). The lake is 6 miles long and has a maximum width of 600 feet.

  18. Effects of land use change and seasonality of precipitation on soil nitrogen in a dry tropical forest area in the Western Llanos of Venezuela.

    PubMed

    González-Pedraza, Ana Francisca; Dezzeo, Nelda

    2014-01-01

    We evaluated changes of different soil nitrogen forms (total N, available ammonium and nitrate, total N in microbial biomass, and soil N mineralization) after conversion of semideciduous dry tropical forest in 5- and 18-year-old pastures (YP and OP, resp.) in the western Llanos of Venezuela. This evaluation was made at early rainy season, at end rainy season, and during dry season. With few exceptions, no significant differences were detected in the total N in the three study sites. Compared to forest soils, YP showed ammonium losses from 4.2 to 62.9% and nitrate losses from 20.0 to 77.8%, depending on the season of the year. In OP, the ammonium content increased from 50.0 to 69.0% at the end of the rainy season and decreased during the dry season between 25.0 and 55.5%, whereas the nitrate content increased significantly at early rainy season. The net mineralization and the potentially mineralizable N were significantly higher (P < 0.05) in OP than in forest and YP, which would indicate a better quality of the substrate in OP for mineralization. The mineralization rate constant was higher in YP than in forest and OP. This could be associated with a reduced capacity of these soils to preserve the available nitrogen.

  19. Effects of Land Use Change and Seasonality of Precipitation on Soil Nitrogen in a Dry Tropical Forest Area in the Western Llanos of Venezuela

    PubMed Central

    González-Pedraza, Ana Francisca; Dezzeo, Nelda

    2014-01-01

    We evaluated changes of different soil nitrogen forms (total N, available ammonium and nitrate, total N in microbial biomass, and soil N mineralization) after conversion of semideciduous dry tropical forest in 5- and 18-year-old pastures (YP and OP, resp.) in the western Llanos of Venezuela. This evaluation was made at early rainy season, at end rainy season, and during dry season. With few exceptions, no significant differences were detected in the total N in the three study sites. Compared to forest soils, YP showed ammonium losses from 4.2 to 62.9% and nitrate losses from 20.0 to 77.8%, depending on the season of the year. In OP, the ammonium content increased from 50.0 to 69.0% at the end of the rainy season and decreased during the dry season between 25.0 and 55.5%, whereas the nitrate content increased significantly at early rainy season. The net mineralization and the potentially mineralizable N were significantly higher (P < 0.05) in OP than in forest and YP, which would indicate a better quality of the substrate in OP for mineralization. The mineralization rate constant was higher in YP than in forest and OP. This could be associated with a reduced capacity of these soils to preserve the available nitrogen. PMID:25610907

  20. Effects of drought in central and south Texas: Chapter C in Drought in the Southwest, 1942-56

    USGS Publications Warehouse

    Thomas, H.E.

    1963-01-01

    The effects of drought upon ground-water storage and discharge, and upon streamflow, vary tremendously in the central third of Texas (the area from the Panhandle to the Gulf of Mexico). Extremes are represented by (a) the Llano Estacado, where the drought had negligible effect upon ground-water resources, which are being progressively depleted by pumping for irrigation; and (b) the Balcones fault-zone aquifer west of San Antonio, whose storage and natural discharge declined substantially during the drought, but increased even more rapidly during succeeding years of more abundant precipitation.

  1. Trypanosoma vivax in water buffalo of the Venezuelan Llanos: An unusual outbreak of wasting disease in an endemic area of typically asymptomatic infections.

    PubMed

    Garcia, Herakles A; Ramírez, Oneyda J; Rodrigues, Carla M F; Sánchez, Rafael G; Bethencourt, Angelica M; Del M Pérez, Gabriela; Minervino, Antonio H H; Rodrigues, Adriana C; Teixeira, Marta M G

    2016-10-30

    Trypanosoma vivax has been associated with asymptomatic infections in African and South American buffalo. In this study, T. vivax was analyzed in water buffalo (Bubalus bubalis) from Venezuela in a molecular survey involving 293 blood samples collected from 2006 to 2015 across the Llanos region. Results demonstrated constant infections (average 23%) during the years analyzed. In general, animals were healthy carriers of T. vivax with low levels of parasitemia and were diagnosed exclusively by TviCATL-PCR. However, an outbreak of severe acute infections mostly in dairy animals was reported during a prolonged drought affecting 30.4% of a buffalo herd (115 animals examined). During the outbreak, animals exhibiting anemia and neurological disorders developed fatal infections, and 7% of the herd died within nine months before treatment against trypanosomosis. Microsatellite locus genotyping (MLG) of T. vivax samples before and during the outbreak revealed similar genotypes, but outbreak isolates exhibited the most divergent MLG. Venezuelan samples from symptomless and sick buffalo did not share the MLGs previously detected in asymptomatic Brazilian buffalo. Trypanosoma evansi was not detected in the herd examined during the outbreak. However, as expected Babesia sp. (62.6%) and Anaplasma sp. (55.6%) infections were highly prevalent in asymptomatic buffalo in the studied areas. This is the first South American outbreak of highly lethal acute T. vivax infections in water buffalo. Our results suggest that chronically infected and asymptomatic buffalo living in areas of enzootic equilibrium can develop symptomatic/lethal disease triggered by stressful scarcity of green forage and water during long droughts, inappropriate management of herds and likely concomitant anaplasmosis and babesiosis. Altogether, these factors weaken buffalo immune defenses, allowing T. vivax to proliferate and, consequently, allowing for progression to wasting disease. Copyright © 2016 Elsevier B

  2. Episodic karstification, Edwards Plateau, central Texas

    SciTech Connect

    Kastning, E.H.

    1985-01-01

    The Edwards Plateau and Llano Basin of central Texas form one of the largest contiguous regions of karst in North America (>80,000 km/sup 2/). Solutional phenomena show that several major episodes of karstification are documentable from late Cambrian to Holocene. Relict landforms representing intervals of solutional activity correlate well with the accepted geomorphic chronology for central Texas. Secondary porosity are vertically controlled by lithology, topographic incision of streams, position of the potentiometric surface, and attitude of bedding. Areally, development of karst is strongly influenced by the extent, density, and orientation of fractures and by hydrodynamic characteristics such as points of recharge and discharge, degree of integration of groundwater flow paths, and hydraulic gradients. Early episodes of karstification correspond to intervals of subaerial exposure of carbonate rocks during marine regression or following regional uplift. Paleokarst is prevalent in the Paleozoic and Mesozoic sequences. Infilled dolines and solution-collapse breccias have been exhumed by extensive regional denudation during the Cenozoic Era. Subaerial conditions during the middle Cretaceous account for infilled solutional cavities within lower Cretaceous carbonate beds. The most extensive karstification began with regional uplift in the early Miocene. Enhanced relief along the Balcones escarpment promoted incision of streams, lowering of water tables, steepened hydraulic gradients, and increases in discharge. Caves at various-elevations attest to sequential dissection of the plateau during the late Quaternary.

  3. Drowning of the Upper Marble Falls carbonate platform (Pennsylvanian), central Texas: A case of conflicting “signals?”

    NASA Astrophysics Data System (ADS)

    Erlich, R. N.; Coleman, J. L.

    2005-04-01

    Marble Falls and Smithwick Formation carbonates and shales were deposited on the western margin of the slowly subsiding Fort Worth Basin of central Texas during Early Pennsylvanian time. The Upper Marble Falls Member carbonate platform back-stepped towards the west-southwest as Smithwick outer shelf-slope black shales drowned platform margin areas to the east. The shelf-to-basin profile observed from subsurface data from the Fort Worth Basin and outcrops from the Llano Uplift area records platform drowning; however, the platform began to shoal upwards as it back-stepped towards the west-southwest, due to the presence of the Llano Uplift paleobathymetric high. The geometry of these facies tracts was controlled primarily by a combination of subsidence and second-order sea-level change, while the development of sequences and unconformities was controlled by third-order sea-level changes and environmental factors, and not subsidence. The termination of platform deposition in the Fort Worth Basin was caused by the interplay of third-order sea-level changes, environmental deterioration in advance of siliciclastic burial, and a lack of accommodation space. The depositional history of the Upper Marble Falls carbonate platform does not fit "classic" examples of drowned platforms described from other areas, but may be typical of platforms in slowly subsiding basins.

  4. Oil and gas developments in South America, Central America, Caribbean area, and Mexico in 1986

    SciTech Connect

    Wiman, W.D.

    1987-10-01

    Exploration activity in South America, Central America, the Caribbean area, and Mexico in 1986 was considerably reduced compared to 1985. Brazil, Colombia, Ecuador, Guatemala, and Venezuela had increased oil production, with Colombia showing a dramatic 71% increase attributed mainly to bringing on-stream the pipeline connecting Occidental-Shell-Ecopetrol's Cano Limon complex to the port of Covenas. Significant discoveries were reported from Argentina in the Olmedo, Oran, and San Jorge basins; Brazil in the offshore Campos and Amazon basins; Colombia in the Llanos basin; Ecuador in the Oriente basin; Mexico in the Bay of Campeche; Peru in the Ucayali basin; and Venezuela in the Eastern Venezuela basin. Eastern Venezuela's Furrial discovery is reported to have recoverable reserves of more than 1 million bbl of oil, and Shell's Ucayali basin discovery is reported to hold more than 7 tcf of gas. 7 figures, 10 tables.

  5. Integrated geophysical and geological studies of selected major tectonic features in south-central U.S

    NASA Astrophysics Data System (ADS)

    Alrefaee, Hamed

    The current dissertation includes three separate chapters, each utilizing the power of the integration of different geophysical datasets with geology to investigate tectonic and structural processes responsible for the geological evolution of selected major tectonic features in south-central U. S. These tectonic features are; the Arkoma basin of Oklahoma and Arkansas, the Llano uplift of central Texas, and the Meers fault of the southwestern Oklahoma. The Arkoma basin is an arcuate structural feature that extends from the Gulf coastal plain in central Arkansas westward 400 km to the Arbuckle Mountains in south-central Oklahoma. The interpretation of the 3-D seismic data reveals an E-W zone of crustal weakness in the northern part of the study area, which could be a Late Paleozoic tectonic inversion of the extension faulting that developed during Cambrian rifting and later foreland basin development. The seismic interpretation reveals a compressive deformation of the Late Paleozoic strata related to the Ouachita orogeny. Magnetic boundaries such as faults andor body edges extending E-W, NE-SW and NW-SE have been delineated using magnetic edge detector techniques in the northern, southeastern, and western parts of the study area, respectively. The Euler magnetic depth estimation method delineated the same faults determined using magnetic edge detector techniques. The maximum depth to faults dominating the basement and/or the intrabasement features determined by the Euler's method is about 3850 m. The fault trends delineated by the seismic interpretation and those determined by the Euler's method and the edge detector techniques show a very clear correlation. The Llano Uplift is a broad structural dome in central Texas with 2 to 3 km of structural relief relative to the subsurface Fort Worth and Kerr basins to the northeast and southwest. The initial uplift due to an arc-continent collision was followed by a continent-continent collision between the Laurentia and a

  6. Central line infections - hospitals

    MedlinePlus

    ... infection; CVC - infection; Central venous device - infection; Infection control - central line infection; Nosocomial infection - central line infection; Hospital acquired infection - central line infection; Patient safety - central ...

  7. Central Italy

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Clouds and haze cover most of the Italian peninsula in this view of central Italy (41.5N, 14.0E) but the Bay of Naples region with Mt. Vesuvius and the island of Capri are clear. The Adriatic Sea in the background separates Italy from the cloud covered Balkans of eastern Europe and the Tyrrhenian Sea in the foreground lies between the Italian mainland and the off scene islands of Corsica and Sardinia. Several aircraft contrails can also be seen.

  8. Oil and gas developments in South America, Central America, Caribbean area, and Mexico in 1987

    SciTech Connect

    Wiman, W.D.

    1988-10-01

    Exploration activity in South America, Central America, the Caribbean area, and Mexico in 1987 showed significant increases in seismic acquisition in Belize, Bolivia, Brazil, Costa Rica, Guatemala, Mexico, Paraguay, and Peru, and a decrease in Chile and Venezuela. Exploratory drilling increased in most major producing countries but was accompanied by a decline in development drilling. Most of the increase could be attributed to private companies fulfilling obligations under risk contracts; however, state oil companies in Bolivia, Chile, and Colombia showed significant increased activity, with only Mexico showing a decrease. Colombia again had a dramatic increase in production (29% from 1986). Noteworthy discoveries were made in Bolivia (Villamontes-1); Brazil, in the Solimoes basin (1-RUC-1-AM); Chile (Rio Honda-1); Colombia, in the Llanos basin (Austral-1, La Reforma-1, Libertad Norte-1, Cravo Este-1, and Cano Yarumal-1), in the Upper Magdalena basin (Toldado-1 and Los Mangos-1); Ecuador (Frontera-1, a joint-exploration venture with Colombia); Mexico, in the Chiapas-Tabasco region (Guacho-1 and Iridi-1), in the Frontera Norte area (Huatempo-1); Peru, in the Madre de Dios basin (Armihuari-4X); Trinidad (West East Queen's Beach-1); and Venezuela (Musipan-1X). Brazil's upper Amazon (Solimoes basin) discovery, Colombia's Upper Magdalena basin discoveries Toldado-1 and Los Mangos-1, Mexico's Chiapas-Tabasco discoveries, Peru's confirmation of the giant Cashiriari discovery of 1986, and Venezuela's success in Monagas state were the highlights of 1987. 5 figs., 8 tabs.

  9. Gambusia quadruncus (Cyprinodontiformes: Poeciliidae): a new species of mosquitofish from east-central México.

    PubMed

    Langerhans, R B; Gifford, M E; Domínguez-Domínguez, O; García-Bedoya, D; DeWitt, T J

    2012-10-01

    Gambusia quadruncus n. sp., the llanos mosquitofish, is described from east-central México. The region inhabited by the species represents a hotspot of diversity of Gambusia, and G. quadruncus sometimes coexists with at least three congeners. The species differs from its closest relative, Gambusia affinis, in several characteristics with plausible effects on reproductive isolation, e.g. body size, body and fin morphology, male genital morphology (distal tip of gonopodium) and female anal spot morphology (colouration near the urogenital sinus). Moreover, combined analysis of mitochondrial and nuclear gene sequence data (c. 2158 total base pairs) indicates reciprocal monophyly of G. quadruncus and its sister species G. affinis, with levels of genetic divergence suggesting the two species diverged from one another over a million years ago. The origin of G. quadruncus may reflect a vicariant event associated with Pliocene orogenesis in the Tamaulipas Arch and a frontal section of the Sierra Madre Oriental (Lleran Mesas). Gambusia quadruncus inhabits a variety of freshwater habitats across several river drainages, with its range spanning at least 350 km from north to south, covering over 25 000 km(2). A key to aid identification of the species is provided. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  10. Central Campus

    NASA Image and Video Library

    2017-05-17

    A long exposure photograph of the new headquarters building, part of the Central Campus in the industrial area at NASA’s Kennedy Space Center in Florida. The nearly-complete seven-story, 200,000-square-foot facility will house about 500 NASA civil service and contractor employees. The building will be more energy efficient than the current Headquarters building and will feature the latest in office and administrative building technology to fulfill Kennedy's role as the premiere spaceport for NASA and, increasingly, commercial entities.

  11. Central pain.

    PubMed

    Singh, Supreet

    2014-12-01

    Questions from patients about pain conditions and analgesic pharmacotherapy and responses from authors are presented to help educate patients and make them more effective self-advocates. The topic addressed in this issue is central pain, a neuropathic pain syndrome caused by a lesion in the brain or spinal cord that sensitizes one's perception of pain. It is a debilitating condition caused by various diseases such as multiple sclerosis, strokes, spinal cord injuries, or brain tumors. Varied symptoms and the use of pharmacological medicines and nonpharmacological therapies will be addressed.

  12. Aquifer mineralogy and natural radionuclides in groundwater-the lower Paleozoic of central Texas

    SciTech Connect

    Kim, Y.; Tieh, T.T.; Ledger, E.B.

    1995-10-01

    Water-mineral interactions in an aquifer may give rise to high levels of Ra and Rn in groundwater. An understanding of aquifer mineralogy is therefore essential to determine the sources of natural radionuclides and design possible means for improving water quality. Anomalous Ra and Rn concentrations have been detected in groundwater produced from the Cambrian Hickory and Cap Mountain aquifers in the Llano Uplift area of central Texas. This study examines cored aquifer rock samples, focusing on the abundance, distribution, and nature of occurrence of minerals containing U and Th, parent nuclides of Ra Rn. The Hickory, 136 m thick, consists of a coarse grained lower, a calcareous middle, and a fossiliferous and hematitic upper unit, with thin shale laminae thoughout. The Cap Mountain, 44 m thick, is a sandy limestone. Detrital materials are composed of 77% quartz, 19% feldspars, and 4% lithic fragments. Accessory minerals average less than 1%. Authigenic minerals, primarily carbonate, clay, and Fe-oxide minerals, make up 18% of the bulk rock. Porosity is of secondary origin. Analysis of U in 123 samples by delayed neutron counting shows an average concentration of 3.6 ppm. Shaly samples generally contain significantly higher U. Gamma ray spectrometric analysis of Th in 20 samples yields an average of 13.9 ppm. Fission-track imaging shows that U occurs predominantly in: (1) phosphatic fossil fragments and intraclasts, especially in the Cap Mountain; (2) thin shaly laminae which are more abundant in the Hickory; (3) authigenic minerals including hematite and clay minerals, also common in the Hickory; and (4) detrital accessory minerals. Mobilization of U and its decay products by groundwater can account for the Ra and Rn in the produced water, particularly from intervals where there are high concentrations of shaly laminae, phosphatic materials, or hematitic cement.

  13. Centralize Printing, and Save.

    ERIC Educational Resources Information Center

    McCormick, Kathleen

    1984-01-01

    Describes the operations of a centralized printing office in a California school district. Centralization greatly increased the efficiency and lowered the cost of generating publications, information services, newsletters, and press releases throughout the school year. (TE)

  14. Central Neuropathic Pain Syndromes.

    PubMed

    Watson, James C; Sandroni, Paola

    2016-03-01

    Chronic pain is common in patients with neurologic complications of a central nervous system insult such as stroke. The pain is most commonly musculoskeletal or related to obligatory overuse of neurologically unaffected limbs. However, neuropathic pain can result directly from the central nervous system injury. Impaired sensory discrimination can make it challenging to differentiate central neuropathic pain from other pain types or spasticity. Central neuropathic pain may also begin months to years after the injury, further obscuring recognition of its association with a past neurologic injury. This review focuses on unique clinical features that help distinguish central neuropathic pain. The most common clinical central pain syndromes-central poststroke pain, multiple sclerosis-related pain, and spinal cord injury-related pain-are reviewed in detail. Recent progress in understanding of the pathogenesis of central neuropathic pain is reviewed, and pharmacological, surgical, and neuromodulatory treatments of this notoriously difficult to treat pain syndrome are discussed.

  15. Central and peripheral demyelination

    PubMed Central

    Mehndiratta, Man Mohan; Gulati, Natasha Singh

    2014-01-01

    Several conditions cause damage to the inherently normal myelin of central nervous system, perepheral nervous system or both central and perepheral nervous system and hence termed as central demyelinating diseases, perepheral demyelinating diseases and combined central and perepheral demyelinating diseases respectively. Here we analysed and foccused on the etiology, prevalance, incidence and age of these demyelinating disorders. Clinical attention and various diagnostic tests are needed to adequately assess all these possibilities. PMID:24741263

  16. Martian Central Pit Craters

    NASA Technical Reports Server (NTRS)

    Hillman, E.; Barlow, N. G.

    2005-01-01

    Impact craters containing central pits are rare on the terrestrial planets but common on icy bodies. Mars is the exception among the terrestrial planets, where central pits are seen on crater floors ( floor pits ) as well as on top of central peaks ( summit pits ). Wood et al. [1] proposed that degassing of subsurface volatiles during crater formation produced central pits. Croft [2] argued instead that central pits might form during the impact of volatile-rich comets. Although central pits are seen in impact craters on icy moons such as Ganymede, they do show some significant differences from their martian counterparts: (a) only floor pits are seen on Ganymede, and (b) central pits begin to occur at crater diameters where the peak ring interior morphology begins to appear in terrestrial planet craters [3]. A study of craters containing central pits was conducted by Barlow and Bradley [4] using Viking imagery. They found that 28% of craters displaying an interior morphology on Mars contain central pits. Diameters of craters containing central pits ranged from 16 to 64 km. Barlow and Bradley noted that summit pit craters tended to be smaller than craters containing floor pits. They also noted a correlation of central pit craters with the proposed rings of large impact basins. They argued that basin ring formation fractured the martian crust and allowed subsurface volatiles to concentrate in these locations. They favored the model that degassing of the substrate during crater formation was responsible for central pit formation due to the preferential location of central pit craters along these basin rings.

  17. Central line complications

    PubMed Central

    Kornbau, Craig; Lee, Kathryn C; Hughes, Gwendolyn D; Firstenberg, Michael S

    2015-01-01

    Central venous access is a common procedure performed in many clinical settings for a variety of indications. Central lines are not without risk, and there are a multitude of complications that are associated with their placement. Complications can present in an immediate or delayed fashion and vary based on type of central venous access. Significant morbidity and mortality can result from complications related to central venous access. These complications can cause a significant healthcare burden in cost, hospital days, and patient quality of life. Advances in imaging, access technique, and medical devices have reduced and altered the types of complications encountered in clinical practice; but most complications still center around vascular injury, infection, and misplacement. Recognition and management of central line complications is important when caring for patients with vascular access, but prevention is the ultimate goal. This article discusses common and rare complications associated with central venous access, as well as techniques to recognize, manage, and prevent complications. PMID:26557487

  18. Central Pit Crater

    NASA Image and Video Library

    2015-11-13

    Crater floors can have a range of features, from flat to a central peak or a central pit. This image from NASA 2001 Mars Odyssey spacecraft shows an unnamed crater in Terra Sabaea has a central pit. This unnamed crater in Terra Sabaea has a central pit. The different floor features develop do due several factors, including the size of the impactor, the geology of the surface material and the geology of the materials at depth. Orbit Number: 60737 Latitude: 22.3358 Longitude: 61.2019 Instrument: VIS Captured: 2015-08-23 20:13 http://photojournal.jpl.nasa.gov/catalog/PIA20092

  19. Implementation of a Single-Column Model for Fog and Low Cloud Forecasting at Central-Spanish Airports

    NASA Astrophysics Data System (ADS)

    Terradellas, Enric; Cano, Darío

    2007-06-01

    Operations at Central-Spanish airports are often, especially in winter, affected by visibility reduction. The Instituto Nacional de Meteorología (INM), the Spanish Weather Service, has developed a single-column model (SCM) in order to improve short-term forecasts of fog, visibility and low-clouds. The SCM, called H1D, is a one-dimensional version of the HIRLAM limited-area model. It is operationally run for three airports in the region: Madrid-Barajas, Almagro and Albacete-Los Llanos. Since SCMs cannot deal with horizontal heterogeneity, the terms that depend on the horizontal structure of the atmosphere are estimated from the outputs of the three-dimensional (3-D) model and introduced into the SCM as external forcings. The systematic analysis of the meteorological situations has evidenced the existence of a close relationship between fog formation and the presence of drainage winds in the region. Since the 3-D model docs not have the necessary resolution to correctly simulate the main features of the drainage flow caused by the complex topography in the proximity of Madrid-Barajas, it cannot provide the SCM with the correct forcings. This problem has been partially overcome through the introduction of a module that, under certain conditions, substitutes the values computed from the 3-D model outputs by others that are based on a conceptual model of the phenomenon and have been empirically derived from climatological knowledge. This module improves the H1D verification scores for the basic meteorological variables—wind, temperature and humidity—and reduces the false alarm rate in fog forecast.

  20. Idiopathic central diabetes Insipidus.

    PubMed

    Grace, Mary; Balachandran, Venu; Menon, Sooraj

    2011-10-01

    Idiopathic central diabetes insipidus (CDI) is a rare disorder characterized clinically by polyuria and polydipsia, and an abnormal urinary concentration without any identified etiology. We report a case of central diabetes insipidus in a 60-year-old lady in the absence of secondary causes like trauma, infection, and infiltrative disorders of brain.

  1. Central College Data Book.

    ERIC Educational Resources Information Center

    Central Coll., McPherson, KS.

    Tabulated data relevant to several aspects of Central College, a private two-year church-related institution, are compiled in this data book. Content includes statistical data and information on: (1) the purposes, objectives, history, and accreditation and memberships of Central College; (2) full- and part-time faculty, faculty utilization,…

  2. Los plaguicidas y la contaminacion del medio ambiente Venezolano

    USGS Publications Warehouse

    Stickel, L.F.; Stickel, W.H.

    1972-01-01

    RESUMEN DE RECOMENDACIONES Recomendaciones para el Programa de Investigacion: 1. Establecer un sistema de muestreo biologico para detectar los niveles tendencias de los productos quimicos toxicos en un peque?o numero de si tios representativos. 2. Mantener continua vigilancia de la contaminacion ambiental, mediante la seleccion acertadamente dirigida de las zonas afectadas y de las fuentes de contaminacion. 3. Realizar estudios acerca de las poblaciones de animales silvestres, y del exito de los procesos reproductivos de las especies o grupos clayes de animales que se consideran mas gravemente afectados. 4. Preparar recomendaciones para una accion gubernamental de proteccion al hombre, a la fauna silvestre y al medio ambiente. Recomendaciones para la Accion Administrativa: 1. Establecer limites a la tolerancia de los residuos de plaguicidas en los alimentos. Constituye una medida clave para disminuir la contaminacion ambiental. 2. Establecer normas de calidad del agua para las corrientes, represas, la gos y otros cuerpos. Es la segunda medida clave para reducir la contaminacion del ambiente 3. Exigir un tratamiento adecuado de los efluentes industriales, especialmente antes de que se construyan las nuevas plantas. 4. Exigir a los agricultores que en el uso de plaguicidas sigan los consejos tecnicos autorizados y negar a los vendedores el derecho a recomendar productos por su cuenta. 5. Tomar medidas para recoger y eliminar los recipientes y sobrantes de los plaguicidas.

  3. Central diffraction at ALICE

    NASA Astrophysics Data System (ADS)

    Lämsä, J. W.; Orava, R.

    2011-02-01

    The ALICE experiment is shown to be well suited for studies of exclusive final states from central diffractive reactions. The gluon-rich environment of the central system allows detailed QCD studies and searches for exotic meson states, such as glueballs, hybrids and new charmonium-like states. It would also provide a good testing ground for detailed studies of heavy quarkonia. Due to its central barrel performance, ALICE can accurately measure the low-mass central systems with good purity. The efficiency of the Forward Multiplicity Detector (FMD) and the Forward Shower Counter (FSC) system for detecting rapidity gaps is shown to be adequate for the proposed studies. With this detector arrangement, valuable new data can be obtained by tagging central diffractive processes.

  4. Central ballast tanker design

    SciTech Connect

    1997-01-01

    The purpose of this paper is to present the CENTRAL BALLAST TANKER Design. This design is intended to reduce the volume of oil spilled from tankers by giving the crew a tanker properly designed and equipped to allow large quantities of oil from ruptured tank(s) to flow safely to a fully-inerted central ballast tank. In addition to reducing the volume of oil spilled, the design also addresses many of the shortcomings of the DOUBLE HULL DESIGN which are increasingly becoming a concern. The following is a brief review of the development of the CENTRAL BALLAST TANKER. The simple operational features, stability, low cost and ease of maintenance of the single hull tanker were important and can be retained with the CENTRAL BALLAST DESIGN.

  5. Central sleep apnea

    MedlinePlus

    ... Ramar K, et al. The treatment of central sleep apnea syndromes in adults: practice parameters with an evidence-based literature review and meta-analyses. SLEEP . 2012;35:17-40. Clodagh MR, Bradley TD. ...

  6. Central nervous system

    MedlinePlus

    The central nervous system is composed of the brain and spinal cord. Your brain and spinal cord serve as the main "processing center" for your entire nervous system. They control all the workings of your body.

  7. Pigmented central neurocytoma.

    PubMed

    Kiehl, Tim-Rasmus; Kalkanis, Steven N; Louis, David N

    2004-06-01

    Central neurocytoma is a low-grade neuronal neoplasm that occurs most often within the lateral ventricles. We report the case of a 60-year-old woman who presented with gait problems, headache and memory loss. Preoperative evaluation demonstrated a heterogeneous, hypervascular and partially cystic mass in the left lateral ventricle. Histopathological examination revealed characteristic features of central neurocytoma, including immunoreactivity for synaptophysin, as well as the unusual feature of abundant pigment in the cytoplasm of tumor cells. Special stains revealed iron, consistent with hemosiderin, but found no evidence of melanin or melanosomes. Previous reports of pigmented central neurocytoma have described the presence of lipofuscin or neuromelanin. To our knowledge, the present case represents the first example of pigmented central neurocytoma secondary to hemosiderin deposition.

  8. Central Peak Crater

    NASA Image and Video Library

    2010-10-07

    As crater size increases, craters become more complex. This moderate size crater contains a central peak, created by rebound of molten material just following the impact. This image was captured by NASA Mars Odyssey on Sept. 8, 2010.

  9. TACS Central Control Facility.

    DTIC Science & Technology

    1981-02-12

    Central Control Facility 6 3. System Management Data Flow 7 B. Hardware Operating Environment 9 1. Computer 9 2. TACS Interfaces 9 3. Other Central...TERMINATION TIMING 131 Appendix C SYSTEM MANAGEMENT DATA FORMATS 135 Appendix D FIVE- AND NINE-SLOT SYSTEM IMPLEMENTATION DIFFERENCES 147 Appendix E...control burst management ) 26 2-7 Call Progress Messages 29 2-8 Flowchart of Assignment/Blockage Decision Process for All-Member Net Requests 30 2-9

  10. Central Diffraction in ALICE

    SciTech Connect

    Schicker, R.

    2011-07-15

    The ALICE experiment consists of a central barrel in the pseudorapidity range -0.9<{eta}<0.9 and of additional detectors covering about 3 units of pseudorapidity on either side of the central barrel. Such a geometry allows the tagging of single and double gap events. The status of the analysis of such diffractive events in proton-proton collisions at {radical}(s) = 7 TeV is presented.

  11. Balanced Centrality of Networks.

    PubMed

    Debono, Mark; Lauri, Josef; Sciriha, Irene

    2014-01-01

    There is an age-old question in all branches of network analysis. What makes an actor in a network important, courted, or sought? Both Crossley and Bonacich contend that rather than its intrinsic wealth or value, an actor's status lies in the structures of its interactions with other actors. Since pairwise relation data in a network can be stored in a two-dimensional array or matrix, graph theory and linear algebra lend themselves as great tools to gauge the centrality (interpreted as importance, power, or popularity, depending on the purpose of the network) of each actor. We express known and new centralities in terms of only two matrices associated with the network. We show that derivations of these expressions can be handled exclusively through the main eigenvectors (not orthogonal to the all-one vector) associated with the adjacency matrix. We also propose a centrality vector (SWIPD) which is a linear combination of the square, walk, power, and degree centrality vectors with weightings of the various centralities depending on the purpose of the network. By comparing actors' scores for various weightings, a clear understanding of which actors are most central is obtained. Moreover, for threshold networks, the (SWIPD) measure turns out to be independent of the weightings.

  12. CENTRAL PLATEAU REMEDIATION

    SciTech Connect

    ROMINE, L.D.

    2006-02-01

    A systematic approach to closure planning is being implemented at the Hanford Site's Central Plateau to help achieve the goal of closure by the year 2035. The overall objective of Central Plateau remediation is to protect human health and the environment from the significant quantity of contaminated material that resulted from decades of plutonium production in support of the nation's defense. This goal will be achieved either by removing contaminants or placing the residual contaminated materials in a secure configuration that minimizes further migration to the groundwater and reduces the potential for inadvertent intrusion into contaminated sites. The approach to Central Plateau cleanup used three key concepts--closure zones, closure elements, and closure process steps--to create an organized picture of actions required to complete remediation. These actions were merged with logic ties, constraints, and required resources to produce an integrated time-phased schedule and cost profile for Central Plateau closure. Programmatic risks associated with implementation of Central Plateau closure were identified and analyzed. Actions to mitigate the most significant risks are underway while high priority remediation projects continue to make progress.

  13. Central auditory imperception.

    PubMed

    Snow, J B; Rintelmann, W F; Miller, J M; Konkle, D F

    1977-09-01

    The development of clinically applicable techniques for the evaluation of hearing impairment caused by lesions of the central auditory pathways has increased clinical interest in the anatomy and physiology of these pathways. A conceptualization of present understanding of the anatomy and physiology of the central auditory pathways is presented. Clinical tests based on reduction of redundancy of the speech message, degradation of speech and binaural interations are presented. Specifically performance-intensity functions, filtered speech tests, competing message tests and time-compressed speech tests are presented with the emphasis on our experience with time-compressed speech tests. With proper use of these tests not only can central auditory impairments by detected, but brain stem lesions can be distinguished from cortical lesions.

  14. Hale Central Peak

    NASA Technical Reports Server (NTRS)

    2004-01-01

    19 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows some of the mountains that make up the central peak region of Hale Crater, located near 35.8oS, 36.5oW. Dark, smooth-surfaced sand dunes are seen to be climbing up the mountainous slopes. The central peak of a crater consists of rock brought up during the impact from below the crater floor. This autumn image is illuminated from the upper left and covers an area approximately 3 km (1.9 mi) across.

  15. Central venous access.

    PubMed

    Ganeshan, Arul; Warakaulle, Dinuke R; Uberoi, Raman

    2007-01-01

    Central venous access plays an important role in the management of an ever-increasing population of patients ranging from those that are critically ill to patients with difficult clinical access. Interventional radiologists are key in delivering this service and should be familiar with the wide range of techniques and catheters now available to them. A comprehensive description of these catheters with regard to indications, technical aspects of catheterization, success rates, and associated early and late complications, as well as a review of various published guidelines on central venous catheter insertion are given in this article.

  16. CENTRALIZATION AND HIGHER EDUCATION.

    ERIC Educational Resources Information Center

    MCKEAN, ROLAND N.

    SUGGESTED COSTS AND BENEFITS OF CENTRALIZED AUTHORITY IN HIGHER EDUCATION AS THEY AFFECT THE BEHAVIOR OF LEGISLATORS, ADMINISTRATORS, VOTERS, TEACHERS, AND STUDENTS, WERE EXAMINED BY COMPARING POLICIES OF DIFFERENT INSTITUTIONS (TWO MULTIVERSITIES OR COORDINATED STATE COLLEGE SYSTEMS, TWO RELATIVELY INDEPENDENT PUBLIC UNIVERSITIES IN ONE STATE,…

  17. CENTRALIZATION OF CAMPUS CONTROLS.

    ERIC Educational Resources Information Center

    1967

    A COLLEGE CAMPUS HAVING A LARGE NUMBER OF SEPARATE BUILDINGS WITH ONE BASIC HEATING AND COOLING SYSTEM IS AN IDEAL SITUATION FOR REALIZING GREAT BENEFITS FROM CENTRALIZED BUILDING CONTROL SYSTEMS. TYPICAL REQUIREMENTS AND ADVANTAGES OF SUCH SYSTEMS ARE DISCUSSED BRIEFLY AND DESCRIPTIONS OF THE SYSTEM AT FOUR MAJOR UNIVERSITIES ARE GIVEN. THIS…

  18. Ghrelin in central neurons.

    PubMed

    Ferrini, F; Salio, C; Lossi, L; Merighi, A

    2009-03-01

    Ghrelin, an orexigenic peptide synthesized by endocrine cells of the gastric mucosa, is released in the bloodstream in response to a negative energetic status. Since discovery, the hypothalamus was identified as the main source of ghrelin in the CNS, and effects of the peptide have been mainly observed in this area of the brain. In recent years, an increasing number of studies have reported ghrelin synthesis and effects in specific populations of neurons also outside the hypothalamus. Thus, ghrelin activity has been described in midbrain, hindbrain, hippocampus, and spinal cord. The spectrum of functions and biological effects produced by the peptide on central neurons is remarkably wide and complex. It ranges from modulation of membrane excitability, to control of neurotransmitter release, neuronal gene expression, and neuronal survival and proliferation. There is not at present a general consensus concerning the source of ghrelin acting on central neurons. Whereas it is widely accepted that the hypothalamus represents the most important endogenous source of the hormone in CNS, the existence of extra-hypothalamic ghrelin-synthesizing neurons is still controversial. In addition, circulating ghrelin can theoretically be another natural ligand for central ghrelin receptors. This paper gives an overview on the distribution of ghrelin and its receptor across the CNS and critically analyses the data available so far as regarding the effects of ghrelin on central neurotransmission.

  19. Multicultural Central Asia.

    ERIC Educational Resources Information Center

    Boyle, Eric D.

    This article addresses the multicultural aspect of Central Asia in response to the discussion on diversity in U.S. classrooms. Many areas of the world are more diverse than the U.S., and these areas experience successes and failures with many of the same issues the U.S. is currently struggling with. Comparing the U.S. diversity debate with similar…

  20. Education in Central America.

    ERIC Educational Resources Information Center

    Waggoner, George R.; Waggoner, Barbara Ashton

    The first chapter of this book describes the physical and cultural environment of Central America and includes analytical comments showing the complexity of the problems confronting the region. Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, and Panama are then treated in separate chapters including: 1) political, economic, social and…

  1. The central hardwood forest

    Treesearch

    F. Bryan Clark

    1989-01-01

    The central hardwood forest covers a vast area of the United States where the dominant native vegetation is hardwood trees. It is one of the largest forest areas in the country and contains about 100 million acres. The forests include more than 70 hardwood tree species, several conifers, many shrubs and herbaceous plants, and a large number of animal species.

  2. Central hardwood notes

    Treesearch

    F. Bryan Clark; Jay G. Hutchinson

    1989-01-01

    The central hardwood forest covers a vast area of the United States where the dominant native vegetation is hardwood trees. It is one of the largest forest areas in the country and contains about 100 million acres. The forests include more than 70 hardwood tree species, several conifers, many shrubs and herbaceaous plants, and a large number of animal species. This...

  3. Central College Perspectives.

    ERIC Educational Resources Information Center

    Knapp, Wesley L.; Hawkins, Calvin H.

    Institutional data are presented which reflect five-year trends in the characteristics of Central College, a two-year institution established by members of the Free Methodist Church of North America in 1884. Data tables present a profile of the faculty with figures for 1972 through 1977 for the following: number and characteristics of full- and…

  4. Central Exclusive Dijet Production

    SciTech Connect

    Dechambre, A.; Cudell, J. R.; Ivanov, I. P.; Hernandez, O.

    2008-08-29

    The ingredients of central exclusive production cross section include large perturbative corrections and soft quantities that must be parametrized and fitted to data. In this talk, we summarize the results of a study of the uncertainties coming from these ingredients, in the case of exclusive dijet production.

  5. Ghrelin in Central Neurons

    PubMed Central

    Ferrini, F; Salio, C; Lossi, L; Merighi, A

    2009-01-01

    Ghrelin, an orexigenic peptide synthesized by endocrine cells of the gastric mucosa, is released in the bloodstream in response to a negative energetic status. Since discovery, the hypothalamus was identified as the main source of ghrelin in the CNS, and effects of the peptide have been mainly observed in this area of the brain. In recent years, an increasing number of studies have reported ghrelin synthesis and effects in specific populations of neurons also outside the hypothalamus. Thus, ghrelin activity has been described in midbrain, hindbrain, hippocampus, and spinal cord. The spectrum of functions and biological effects produced by the peptide on central neurons is remarkably wide and complex. It ranges from modulation of membrane excitability, to control of neurotransmitter release, neuronal gene expression, and neuronal survival and proliferation. There is not at present a general consensus concerning the source of ghrelin acting on central neurons. Whereas it is widely accepted that the hypothalamus represents the most important endogenous source of the hormone in CNS, the existence of extra-hypothalamic ghrelin-synthesizing neurons is still controversial. In addition, circulating ghrelin can theoretically be another natural ligand for central ghrelin receptors. This paper gives an overview on the distribution of ghrelin and its receptor across the CNS and critically analyses the data available so far as regarding the effects of ghrelin on central neurotransmission. PMID:19721816

  6. Diurnal Patterns of Blowing Dust on the Llano Estacado

    USDA-ARS?s Scientific Manuscript database

    Using a Tapered Element Oscillating Microbalance (TEOM), hourly dust data was collected in Lubbock, Texas, from January 1, 2003, to January 1, 2008. Diurnal patterns of dust concentration were computed by averaging hourly values associated with a given “time of day” for all days within the 5-yr sa...

  7. Velarde and the Llano Canal: A Case Study

    ERIC Educational Resources Information Center

    Horvath, Rosemary

    1976-01-01

    In arid New Mexico, decisions about water have always been a particularly strong source of tension between local communities and the bureaucracy. In one revent case, the community of Velarde had successfully blocked plans for a diversion dam and canal which would have brought new water into the Espanola valley, but would also have destroyed…

  8. [CENTRAL ANTICHOLINERGIC... SYNDROME?].

    PubMed

    Danilov, M S; Lebedinskii, K M

    2015-01-01

    While reading special literature in diferent languages the authors noted surprising fact: the term and concept of "central anticholinergic syndrome" is well-known as common anaesthesia complication in German (abbr: ZAS) and partially Spanish sources, but in Russian, English or French literature is used only in toxicological context. Describing etiology, pathogenesis, symptoms, diagnosis and treatment of the complication manifesting with comatose, agitated or shivering forms, the authors analyzing the reasons for such a noticeably diferent approaches to the situation reaching 10% of all the general anaesthesia cases. Probably, ZAS isn't nosologically clearly defined syndrome, but just adverse appearance of one of the fundamental general anaesthesia mechanisms? Anyway, the problem of central cholinergic activity suppression, excessive by its amplitude and/or duration, exists all over the world. German concept of ZAS allows the anaesthesiologist to resolve it on pathogenically generalized basis, while in other professional communities various symptomatic approaches seem to be more common.

  9. FNAL central email systems

    SciTech Connect

    Schmidt, Jack; Lilianstrom, Al; Pasetes, Ray; Hill, Kevin; /Fermilab

    2004-10-01

    The FNAL Email System is the primary point of entry for email destined for an employee or user at Fermilab. This centrally supported system is designed for reliability and availability. It uses multiple layers of protection to help ensure that: (1) SPAM messages are tagged properly; (2) All mail is inspected for viruses; and (3) Valid mail gets delivered. This system employs numerous redundant subsystems to accomplish these tasks.

  10. Fires in Central America

    NASA Technical Reports Server (NTRS)

    2002-01-01

    As can be seen in this true-color scene acquired on April 2, 2002, many fires dot the landscape across portions of Central America. This image spans from Mexico's Yucatan Peninsula across Guatemala and into El Salvador and Honduras. This image was acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra satellite. The red boxes indicate where active fires were burning.

  11. Central nervous system toxicity.

    PubMed

    Ruha, Anne-Michelle; Levine, Michael

    2014-02-01

    Central nervous system toxicity caused by xenobiotic exposure is a common reason for presentation to the emergency department. Sources of exposure may be medicinal, recreational, environmental, or occupational; the means of exposure may be intentional or unintended. Toxicity may manifest as altered thought content resulting in psychosis or confusion; may affect arousal, resulting in lethargy, stupor, or coma; or may affect both elements of consciousness. Seizures may also occur. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. [Central neurocytoma: case report].

    PubMed

    Bouaziz, M; Mansour, A; Feknous, S; Yassi, F; Smati, S; Belhouchet, S; Lankar, A

    2009-12-01

    In this study, we report one case of central neurocytoma treated in our department. It is a benign tumor of the lateral ventricles of the brain with neuronal differentiation. The clinical symptoms mainly consisted in intracranial hypertension syndrome. Immunohistochemical studies are necessary for the histopathological diagnosis. The treatment of choice is surgical. To guarantee good progression, complete ablation is necessary. The clinical progression, radiological aspects, treatment, histopathology, and postoperative progression will be discussed.

  13. [Centralization versus decentralization. Hematology].

    PubMed

    Borregaard, Niels

    2006-04-10

    Clinical haematology is the result of teamwork among dedicated specialists in pathology, molecular diagnostics, imaging, radiotherapy and the haematologist, who in turn can focus on only a limited fraction of the various and highly complex diseases that together constitute clinical haematology. The treatment of patients should be centralized in departments large enough to permit internal subspecialization and to provide expert service focused on haematology. No more than three such hematology centers are needed in Denmark.

  14. Centrality based Document Ranking

    DTIC Science & Technology

    2014-11-01

    approach. We model the documents to be ranked as nodes in a graph and place edges between documents based on their similarity. Given a query, we compute...similarity of the query with respect to every document in the graph . Based on these similarity values, documents are ranked for a given query...clinical documents using centrality based approach. We model the documents to be ranked as nodes in a graph and place edges between documents based on their

  15. [The central pattern generators].

    PubMed

    Balaban, P M; Vorontsov, D D; Dyakonova, V E; Dyakonova, T L; Zakharov, I S; Korshunova, T A; Orlov, O Yu; Pavlova, G A; Panchin, Yi V; Sakharov, D A; Falikman, M V

    2013-01-01

    The central pattern generator (CPG) is defined as a set of neurons involved in joint production of patterned motor output. The roundtable discussion on the CPG was a part of the 5th All-Russian Conference on Animal Behavior (Moscow, Nov. 21, 2012). The discussion centred on three core themes: 1) the mechanisms of the organization and reconfiguration of pattern generating neuronal ensembles, 2) extrapolations that extend the CPG concept beyond the motor systems, and 3) evolutionary and developmental aspects of CPG.

  16. Central corneal abscess.

    PubMed

    van Bijsterveld, O P

    1976-05-01

    Central corneal abscess developed in the experimental animal after inoculation of biologically active staphylococcal strains in a paracentral epithelial lesion of the cornea. These abscesses did not ulcerate, developed only with high inocula, occurred more frequently in immunized rabbits. A serpiginous type of ulceration did not develop at the site of the initial epithelial lesion nor at any other place in the cornea. Histologically, the lesions consisted of densely packed polymorphonuclear leukocytes between the corneal lamellae.

  17. Gangs in Central America

    DTIC Science & Technology

    2007-08-02

    564 ( Engel ) recognizing that violence poses an increasingly serious threat to peace and stability in Central America and supporting expanded...2005; UNODC, May 2007. 10 For example, see Federico Brevé, former Minister of Defense of Honduras, “The Maras: A Menace to the Americas,” Military...police training and judicial reform. On July 31, 2007, the House Committee on Foreign Affairs approved H.Res. 564 ( Engel ) recognizing that violence

  18. Gangs in Central America

    DTIC Science & Technology

    2008-10-17

    activity and in the handling of deported gang members. However, none of those bills were enacted. On October 2, 2007, the House passed H.Res. 564 ( Engel ...UNODC, May 2007. 12 For example, see Federico Brevé, former Minister of Defense of Honduras, “The Maras: A Menace to the Americas,” Military Review...passed H.Res. 564 ( Engel ) supporting expanded cooperation between the United States and Central America to combat crime and violence. Mérida

  19. Gangs in Central America

    DTIC Science & Technology

    2008-03-27

    handling of deported gang members, but none of those bills were enacted. On October 2, 2007, the House passed H.Res. 564 ( Engel ) supporting expanded...crimes committed CRS-4 12 For example, see Federico Brevé, former Minister of Defense of Honduras, “The Maras: A Menace to the Americas,” Military...examined the effects of U.S. deportations on Central America. On October 2, 2007, the House passed H.Res. 564 ( Engel ) supporting expanded

  20. [Central precocious puberty].

    PubMed

    Krysiak, Robert; Marek, Bogdan; Okopień, Bogusław

    2008-01-01

    Central precocious puberty, defined as the onset of puberty before the age 8 years in girls and 9 years in boys, results from a premature activation of gonadotropin-releasing hormone neurons in the hypothalamus. This condition is characterised by early pubertal changes, acceleration of growth velocity, and rapid bone maturation that often result in reduced adult height. It may be either idiopathic or associated with hypothalamic hamartoma, brain neoplasms, numerous non-cancerous disorders of the central nervous system and treatment of peripheral precocious puberty. The goal of the initial assessment of children is to exclude the presence of all these organic disorders. The diagnosis should include detailed anamnesis and clinical examination, measurement of pituitary and sex hormones, assessment of bone age, and imaging of the hypothalamus, pituitary gland, abdomen, pelvis and gonads. The treatment of choice are gonadotropin-releasing hormone agonists. In this paper, we review the current views on the etiopathogenesis, clinical presentation, diagnosis and management of central precocious puberty.

  1. West and Central Africa.

    PubMed

    Lydie, N; Robinson, N J

    1998-01-01

    This article reviews scientific and other literature during the 1990s that links migration and mobility with the spread of sexually transmitted diseases (STDs), including HIV/AIDS. The focus is on key population groups linked to the spread of HIV and STDs in West and Central Africa: migrant laborers, truck drivers, itinerant traders, commercial sex workers (CSWs), and refugees. Countries with high emigration and immigration tend to have high levels of HIV infection, with the exception of Senegal. The main destination of immigrants are Senegal, Nigeria, and Cote d'Ivoire in West Africa and Cameroon, Congo, Gabon, and Congo in Central Africa. The risk of infection and the spread of HIV is variable among migrants. There is little in the literature that substantiates hypotheses about the strong association between migration and HIV-positive status. Information is needed on the duration, frequency of return visits, living conditions, sexual activities with multiple partners, and information before departure, along the routes, at final destination, and at the time of returns. Action-based research in five West African countries (Burkina Faso, Cote d'Ivoire, Mali, Niger, and Senegal) should produce results in late 1998. Comparable studies in Central Africa are unknown. Regional studies should be complemented by local studies. Prevention would benefit from studies on the relative size of these five population groups by geographic location.

  2. Central effects of fingolimod.

    PubMed

    Cruz, Vítor T; Fonseca, Joaquim

    2014-08-01

    Introduccion. El fingolimod, un modulador del receptor de la esfingosina-1-fosfato (S1P) dotado de un mecanismo de accion novedoso, fue el primer tratamiento oral aprobado para la esclerosis multiple remitente recurrente. Su union a los receptores S1P1 de los linfocitos promueve la retencion selectiva de los linfocitos T virgenes y de memoria central en los tejidos linfoides secundarios, lo que impide su salida hacia el sistema nervioso central (SNC). Asimismo, el fingolimod atraviesa con facilidad la barrera hematoencefalica, y diversos estudios le atribuyen un efecto neuroprotector directo en el SNC. Objetivo. Revisar la informacion disponible acerca de los efectos centrales del fingolimod. Desarrollo. El desequilibrio entre los procesos lesivos y reparadores constituye un reflejo de la desmielinizacion cronica, la degeneracion axonal y la gliosis, y parece contribuir a la discapacidad que la esclerosis multiple acarrea. La facilidad con la que el fingolimod atraviesa la barrera hematoencefalica le permite actuar directamente sobre los receptores S1P localizados en las celulas del SNC. Una vez en el interior del SNC, ocupa los receptores S1P de los oligodendrocitos y de sus celulas precursoras, de los astrocitos, los microgliocitos y las neuronas, fomentando la remielinizacion, la neuroproteccion y los procesos endogenos de regeneracion. La eficacia evidenciada en los ensayos clinicos concuerda con un mecanismo de accion que incluiria efectos directos sobre las celulas del SNC. Conclusiones. Los datos disponibles indican que la eficacia del fingolimod en el tratamiento de la esclerosis multiple se debe a su ambivalencia como molecula inmunomoduladora y moduladora directa de los receptores S1P del SNC. Tanto es asi que estudios recientes le atribuyen efectos neuroprotectores en varios modelos que suscitan expectativas en torno a su posible aplicacion terapeutica en la enfermedad de Alzheimer, el paludismo cerebral y el neuroblastoma, asi como en la neuroproteccion

  3. Central American resource studies

    SciTech Connect

    Van Eeckhout, E.; Laughlin, A.W.

    1989-01-01

    Los Alamos National Laboratory has been working with five Central American countries to assist in the development of their energy and mineral resources. Since 1985, mineral resources in Costa Rica, peat resources in Costa Rica and Panama, geothermal energy resources in Honduras and Guatemala, and geothermal field development in El Salvador and Costa Rica have been topics of study. This paper presents an overview of this work -- within these proceedings are papers that deal with specific aspects of each topic, and these will be duly noted. 15 refs., 4 figs.

  4. Fires in Central America

    NASA Technical Reports Server (NTRS)

    2002-01-01

    As can be seen in this true-color scene acquired on April 2, 2002, many fires dot the landscape across portions of Central America. This image spans from Mexico's Yucatan Peninsula across Guatemala and into El Salvador and Honduras. This image was acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra satellite. The red boxes (click on the image above to see it at 250-meter resolution) indicate where active fires were burning. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  5. Fires in Central Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Hundreds of fires are set every year during the dry season in Central Africa. This true color image from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) shows dozens of smoke plumes in the Democratic Republic of the Congo on June 29, 2000. Residents burn away scrub and brush annually in the woody savanna to clear land for farming and grazing. For more information, visit the SeaWiFS Home Page, Global Fire Monitoring Fact Sheet, and 4km2 Fire Data Image Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  6. Flooding in Central Siberia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A mixture of snowmelt and ice jams in late May and June of this year caused the Taz River (left) and the Yenisey River (right) in central Siberia to overflow their banks. The flooding can be seen in this image taken on June 11, 2002, by the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard the Terra satellite. Normally, the rivers would resemble thin black lines in MODIS imagery. In the false-color images sage green and rusty orange is land, and water is black. Clouds are white and pink. Credit: Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  7. Floods in Central China

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This pair of true- and false-color images from the Moderate resolution Imaging Spectroradiometer (MODIS) shows flooding in central China on July 4, 2002. In the false-color image vegetation appears orange and water appears dark blue to black. Because of the cloud cover and the fact that some of the water is filled with sediment, the false-color image provides a clearer picture of where rivers have exceeded their banks and lakes have risen. The river in this image is the Yangtze River, and the large lake is the Poyang Hu. Credits: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  8. Flooding in Central Siberia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A mixture of snowmelt and ice jams in late May and June of this year caused the Taz River (left) and the Yenisey River (right) in central Siberia to overflow their banks. The flooding can be seen in this image taken on June 11, 2002, by the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard the Terra satellite. Normally, the rivers would resemble thin black lines in MODIS imagery. In the false-color images sage green and rusty orange is land, and water is black. Clouds are white and pink. Credit: Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  9. Central Campus Construction Progress

    NASA Image and Video Library

    2016-10-18

    A large crane towers overhead as the new, seven-story headquarters building takes shape in the industrial area at NASA’s Kennedy Space Center in Florida. The 200,000-square-foot facility will anchor the spaceport’s Central Campus and house about 500 NASA civil service and contractor employees. The building will be more energy efficient than the current Headquarters building and will feature the latest in office and administrative building technology to fulfill Kennedy's role as the premiere multi-user spaceport for NASA and, increasingly, commercial entities.

  10. Floods in Central China

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This pair of true- and false-color images from the Moderate resolution Imaging Spectroradiometer (MODIS) shows flooding in central China on July 4, 2002. In the false-color image vegetation appears orange and water appears dark blue to black. Because of the cloud cover and the fact that some of the water is filled with sediment, the false-color image provides a clearer picture of where rivers have exceeded their banks and lakes have risen. The river in this image is the Yangtze River, and the large lake is the Poyang Hu. Credits: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  11. Fires in Central Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Hundreds of fires are set every year during the dry season in Central Africa. This true color image from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) shows dozens of smoke plumes in the Democratic Republic of the Congo on June 29, 2000. Residents burn away scrub and brush annually in the woody savanna to clear land for farming and grazing. For more information, visit the SeaWiFS Home Page, Global Fire Monitoring Fact Sheet, and 4km2 Fire Data Image Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  12. Central Campus Construction Progress

    NASA Image and Video Library

    2016-10-18

    The new headquarters building’s seven floors are clearly visible as construction continues in the industrial area at NASA’s Kennedy Space Center in Florida. The 200,000-square-foot facility will anchor the spaceport’s Central Campus and house about 500 NASA civil service and contractor employees. The building will be more energy efficient than the current Headquarters building and will feature the latest in office and administrative building technology to fulfill Kennedy's role as the premiere multi-user spaceport for NASA and, increasingly, commercial entities.

  13. Central Vision in the Newborn.

    ERIC Educational Resources Information Center

    Lewis, Terri L.; Maurer, Daphne

    1980-01-01

    Tests newborns' ability to detect a dot with central vision and compares both the proportion of time the infants fixated centrally and the duration of each central fixation. Subjects were 46 newborns ranging in age from 1 to 7 days. (MP)

  14. Feature Centrality and Property Induction

    ERIC Educational Resources Information Center

    Hadjichristidis, Constantinos; Sloman, Steven; Stevenson, Rosemary; Over, David

    2004-01-01

    A feature is central to a concept to the extent that other features depend on it. Four studies tested the hypothesis that people will project a feature from a base concept to a target concept to the extent that they believe the feature is central to the two concepts. This centrality hypothesis implies that feature projection is guided by a…

  15. Central diabetes insipidus.

    PubMed

    Arima, Hiroshi; Azuma, Yoshinori; Morishita, Yoshiaki; Hagiwara, Daisuke

    2016-12-01

    Central diabetes insipidus (CDI), characterized by polyuria and polydipsia, is caused by deficiency of arginine vasopressin (AVP), an antidiuretic hormone which acts on V2 receptors in kidney to promote reabsorption of free water. CDI is classified into three subtypes; idiopathic, secondary and familial. A previous study suggests that infundibulo-neurohypophysitis might be an underlying cause of idiopathic CDI. Among secondary CDI, the tumors in the central nervous system such as craniopharyngioma and germ cell tumors are the most frequent causes. Familial CDI is inherited mostly in an autosomal dominant mode, and the number of causal mutations in the AVP gene locus reported so far exceeds 80. CDI is treated with desmopressin, an analogue of vasopressin, and the tablet is preferred to the nasal form because it is easier to administer. It is also shown that the oral disintegrating tablet formula increases QOL and decreases the incidence of hyponatremia in CDI patients. In some CDI patients, the osmoreceptors in the hypothalamus do not function and patients do not sense thirst. These adipsic CDI patients are treated with desmopressin and adjusting the amount of daily water intake based on body weight measurement; but controlling the water balance is extremely difficult, and morbidity and mortality are shown to be high in these patients.

  16. Central diabetes insipidus

    PubMed Central

    Arima, Hiroshi; Azuma, Yoshinori; Morishita, Yoshiaki; Hagiwara, Daisuke

    2016-01-01

    ABSTRACT Central diabetes insipidus (CDI), characterized by polyuria and polydipsia, is caused by deficiency of arginine vasopressin (AVP), an antidiuretic hormone which acts on V2 receptors in kidney to promote reabsorption of free water. CDI is classified into three subtypes; idiopathic, secondary and familial. A previous study suggests that infundibulo-neurohypophysitis might be an underlying cause of idiopathic CDI. Among secondary CDI, the tumors in the central nervous system such as craniopharyngioma and germ cell tumors are the most frequent causes. Familial CDI is inherited mostly in an autosomal dominant mode, and the number of causal mutations in the AVP gene locus reported so far exceeds 80. CDI is treated with desmopressin, an analogue of vasopressin, and the tablet is preferred to the nasal form because it is easier to administer. It is also shown that the oral disintegrating tablet formula increases QOL and decreases the incidence of hyponatremia in CDI patients. In some CDI patients, the osmoreceptors in the hypothalamus do not function and patients do not sense thirst. These adipsic CDI patients are treated with desmopressin and adjusting the amount of daily water intake based on body weight measurement; but controlling the water balance is extremely difficult, and morbidity and mortality are shown to be high in these patients. PMID:28008190

  17. Future Flight Central

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA 'Future Flight Central,' the world's first full-scale virtual airport control tower, opened December 13, 1999 at NASA Ames Research Center, Moffett Field, California. Constructed at a cost of $10 million, the two story facility was jointly funded by NASA and the Federal Aviation Administration (FAA). The facility is designed to test ways to solve potential air and ground traffic problems at commercial airports under realistic airport conditions and configurations. The facility provides an opportunity for airlines and airports to mitigate passenger delays by fine tuning airport hub operations, gate management, ramp movement procedures, and various other airport improvements. Twelve rear projection screens provide a seamless 360 degree high- resolution view of the airport or other screens being depicted. The imaging system, powered by supercomputers, provides a realistic view of weather conditions, enviromental and seasonal effects and the movement of up to 200 active aircraft and ground vehicles.

  18. Flooding in Central China

    NASA Technical Reports Server (NTRS)

    2002-01-01

    During the summer of 2002, frequent, heavy rains gave rise to floods and landslides throughout China that have killed over 1,000 people and affected millions. This false-color image of the western Yangtze River and Dongting Lake in central China was acquired on August 21, 2002, by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. (right) The latest flooding crisis in China centers on Dingtong Lake in the center of the image. Heavy rains have caused it to swell over its banks and swamp lakefront towns in the province of Hunan. As of August 23, 2002, more than 250,000 people have been evacuated, and over one million people have been brought in to fortify the dikes around the lake. Normally the lake would appear much smaller and more defined in the MODIS image. Credit: Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC.

  19. Central solar energy receiver

    DOEpatents

    Drost, M. Kevin

    1983-01-01

    An improved tower-mounted central solar energy receiver for heating air drawn through the receiver by an induced draft fan. A number of vertically oriented, energy absorbing, fin-shaped slats are radially arranged in a number of concentric cylindrical arrays on top of the tower coaxially surrounding a pipe having air holes through which the fan draws air which is heated by the slats which receive the solar radiation from a heliostat field. A number of vertically oriented and wedge-shaped columns are radially arranged in a number of concentric cylindrical clusters surrounding the slat arrays. The columns have two mirror-reflecting sides to reflect radiation into the slat arrays and one energy absorbing side to reduce reradiation and reflection from the slat arrays.

  20. Familial central serous retinopathy.

    PubMed

    Oosterhuis, J A

    1996-05-01

    To study the familial occurrence of central serous retinopathy (CSR). We pooled data from eight eye clinics in Western Europe. We collected 11 families that each had two to four members with CSR. In 10 families siblings and in one family a mother and son were affected. Sixty percent of the patients were male and 40% female. CSR was found in 55 (92%) of 60 eyes, 44 (80%) showing a chronic course. In 25 patients (83%) both eyes were affected. Most recent visual acuity was 0.5 or less in 17 (39%) and 0.2 or less in 8 (18%) of the eyes with chronic CSR. Our findings of familial occurrence and a chronic disorder that is progressive, diffuse, and bilateral suggest an inborn disposition to develop a clinically manifest disintegration of the retinal pigment epithelium in adulthood.

  1. Central Campus Construction Progress

    NASA Image and Video Library

    2017-03-17

    NASA's Kennedy Space Center in Florida is a premier, multi-user spaceport with ongoing construction adding new, ultra-modern facilities. A key element of the Central Campus makeover is a new, seven-story, 200,000-square-foot headquarters building that has taken shape in the heart of the spaceport. The headquarters building's glass facade, as seen from NASA Causeway, is complete. The exterior skin of the building also is nearly finished. The remainder of the glass components are being installed on each floor. Construction of interior walls and utilities on most floors is well underway. Construction of the headquarters building is targeted for completion in November 2017 and employees are expected to be able to move in soon after.

  2. Flooding in Central China

    NASA Technical Reports Server (NTRS)

    2002-01-01

    During the summer of 2002, frequent, heavy rains gave rise to floods and landslides throughout China that have killed over 1,000 people and affected millions. This false-color image of the western Yangtze River and Dongting Lake in central China was acquired on August 21, 2002, by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. (right) The latest flooding crisis in China centers on Dingtong Lake in the center of the image. Heavy rains have caused it to swell over its banks and swamp lakefront towns in the province of Hunan. As of August 23, 2002, more than 250,000 people have been evacuated, and over one million people have been brought in to fortify the dikes around the lake. Normally the lake would appear much smaller and more defined in the MODIS image. Credit: Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC.

  3. Haze in central China

    NASA Image and Video Library

    2017-09-27

    The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite acquired this natural-color image of central China on January 23, 2013 at 04:05 UTC. The image shows extensive haze over the region. In areas where the ground is visible, some of the landscape is covered with lingering snow. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  4. Central pit craters on Ganymede

    NASA Astrophysics Data System (ADS)

    Alzate, Nathalia; Barlow, Nadine G.

    2011-02-01

    Central pit craters are common on Mars, Ganymede and Callisto, and thus are generally believed to require target volatiles in their formation. The purpose of this study is to identify the environmental conditions under which central pit craters form on Ganymede. We have conducted a study of 471 central pit craters with diameters between 5 and 150 km on Ganymede and compared the results to 1604 central pit craters on Mars (diameter range 5-160 km). Both floor and summit pits occur on Mars whereas floor pits dominate on Ganymede. Central peak craters are found in similar locations and diameter ranges as central pit craters on Mars and overlap in location and at diameters <60 km on Ganymede. Central pit craters show no regional variations on either Ganymede or Mars and are not concentrated on specific geologic units. Central pit craters show a range of preservation states, indicating that conditions favoring central pit formation have existed since crater-retaining surfaces have existed on Ganymede and Mars. Central pit craters on Ganymede are generally about three times larger than those on Mars, probably due to gravity scaling although target characteristics and resolution also may play a role. Central pits tend to be larger relative to their parent crater on Ganymede than on Mars, probably because of Ganymede's purer ice crust. A transition to different characteristics occurs in Ganymede's icy crust at depths of 4-7 km based on the larger pit-to-crater-diameter relationship for craters in the 70-130-km-diameter range and lack of central peaks in craters larger than 60-km-diameter. We use our results to constrain the proposed formation models for central pits on these two bodies. Our results are most consistent with the melt-drainage model for central pit formation.

  5. Central America's shrinking forests.

    PubMed

    1992-01-01

    This news brief reports that 66% of deforestation in Central America has happened in the past 40 years, based on World Conservation Union (WCU) data. Deforestation is expected to continue. The population of Central America and Mexico grew by 28% between 1977 and 1987. Growth is decreasing but remains high at 2.5% in all countries of the region except Panama. 29 million was the regional population in 1990; the projection is for 63 million by 2025. Population is migrating to urban centers. Forests declined by 13% and croplands increased from 4% to 13% of total land area and pasture land from 2% to 37%. There was an increase in unproductive land from 145 to 24%, i.e., 50% of El Salvador's land had soil degradation as does 30% of Guatemala's. In addition to deforestation and soil degradation, there has been soil erosion leading to sedimentation buildup near dam sites and in rivers, which diminishes hydroelectric power capability. Silting also affects groundwater resources, which impact on a safe drinking water supply. Population growth results in increased demand for fuelwood, urban land, and agricultural land. New techniques practiced widely are needed in order to meet the region's needs or demands. Slowing population growth buys time for adjusting to the necessary changes needed for sustaining the region's population. WCU urges conservation organizations to raise awareness about the role population plays in environmental degradation, and to support efforts to reduce birth rates. Women's status needs to be improved through income-generating projects, for instance, and cooperation is needed between conservation groups and organizations involved with improving maternal and child health.

  6. [MANAGEMENT OF CENTRAL HYPERSOMNIAS].

    PubMed

    Dauvilliers, Yves; Lopez, Régis

    2016-06-01

    Central hypersomnias include narcolepsy type 1, type 2 and idiopathic hypersomnia with daytime sleepiness excessive in the foreground of the clinical symptoms. Despite major advances in our understanding of the mechanisms of the narcolepsy type 1 with a low level of hypocretin-1 in cerebrospinal fluid, its current management is only symptomatic. The current management is also only symptomatic for type 2 narcolepsy and idiopathic hypersomnia with an unknown pathophysiology. Treatment options may vary from a single drug targeting several symptoms or several drugs treating a specific symptom. The treatment of daytime sleepiness is based on modafinil in first intention. Other psychostimulants such as methylphenidate, pitolisant and exceptionally dextro-amfetamine may be considered. In narcolepsy type 1, antidepressants such as inhibitors of the reuptake of serotonin and noradrenaline will be considered to improve cataplexy. Sodium oxybate is an effective treatment on sleepiness, cataplexy and bad night sleep in narcolepsy. The management for other symptoms or comorbidities should be considered it necessary such as hallucinations, sleep paralysis, the disturbed nighttime sleep, unpleasant dreams, parasomnias, depressive symptoms, overweight/obesity, cardiovascular disease and obstructive sleep apnea syndrome. Important therapeutic perspectives are to be expected concerning new psychostimulant and anticataplectiques, but mainly on immune-based therapies administered as early as possible after disease onset and on hypocretin replacement therapy for patients with severe symptoms.

  7. Mexico and Central America.

    PubMed

    Bronfman, M

    1998-01-01

    This article reviews the literature on migration and HIV/AIDS in Mexico and Central America, including Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama. Most migrants travel to the US through Mexico. US-Mexico trade agreements created opportunities for increased risk of HIV transmission. The research literature focuses on Mexico. Most countries, with the exception of Belize and Costa Rica, are sending countries. Human rights of migrants are violated in transit and at destination. Migration policies determine migration processes. The Mexican-born population in the US is about 3% of US population and 8% of Mexico's population. About 22% arrived during 1992-97, and about 500,000 are naturalized US citizens. An additional 11 million have a Mexican ethnic background. Mexican migrants are usually economically active men who had jobs before leaving and were urban people who settled in California, Texas, Illinois, and Arizona. Most Mexican migrants enter illegally. Many return to Mexico. The main paths of HIV transmission are homosexual, heterosexual, and IV-drug-injecting persons. Latino migrants frequently use prostitutes, adopt new sexual practices including anal penetration among men, greater diversity of sexual partners, and use of injectable drugs.

  8. Central Disorders of Hypersomnolence

    PubMed Central

    Khan, Zeeshan

    2015-01-01

    The central disorders of hypersomnolence are characterized by severe daytime sleepiness, which is present despite normal quality and timing of nocturnal sleep. Recent reclassification distinguishes three main subtypes: narcolepsy type 1, narcolepsy type 2, and idiopathic hypersomnia (IH), which are the focus of this review. Narcolepsy type 1 results from loss of hypothalamic hypocretin neurons, while the pathophysiology underlying narcolepsy type 2 and IH remains to be fully elucidated. Treatment of all three disorders focuses on the management of sleepiness, with additional treatment of cataplexy in those patients with narcolepsy type 1. Sleepiness can be treated with modafinil/armodafinil or sympathomimetic CNS stimulants, which have been shown to be beneficial in randomized controlled trials of narcolepsy and, quite recently, IH. In those patients with narcolepsy type 1, sodium oxybate is effective for the treatment of both sleepiness and cataplexy. Despite these treatments, there remains a subset of hypersomnolent patients with persistent sleepiness, in whom alternate therapies are needed. Emerging treatments for sleepiness include histamine H3 antagonists (eg, pitolisant) and possibly negative allosteric modulators of the gamma-aminobutyric acid-A receptor (eg, clarithromycin and flumazenil). PMID:26149554

  9. Central nervous system stimulants.

    PubMed

    George, A J

    2000-03-01

    Three major types of CNS stimulant are currently abused in sport: amphetamine, cocaine and caffeine. Each drug type has its own characteristic mechanism of action on CNS neurones and their associated receptors and nerve terminals. Amphetamine is widely abused in sports requiring intense anaerobic exercise where it prolongs the tolerance to anaerobic metabolism. It is addictive, and chronic abuse causes marked behavioural change and sometimes psychosis. Major sports abusing amphetamine are cycling, American football, ice-hockey and baseball. Cocaine increases tolerance to intense exercise, yet most of its chronic effects on energy metabolism are negative. Its greatest effects seem to be as a central stimulant and the enhancement of short-term anaerobic exercise. It is highly addictive and can cause cerebral and cardiovascular fatalities. Caffeine enhances fatty acid metabolism leading to glucose conservation, which appears to benefit long-distance endurance events such as skiing. Caffeine is also addictive, and chronic abuse can lead to cardiac damage. Social abuse of each of the three drugs is often difficult to distinguish from their abuse in sport.

  10. [Central infantile hypotonia syndrome].

    PubMed

    Lesný, I; Prosková, M; Lehovský, M

    1989-04-14

    Czechoslovak child neurologists devoted much attention to central infantile hypotonic syndrome (CIHS) in a series of investigations conducted in 1959-1986. They found that it is a developmental syndrome caused by affection of the immature brain, and later, at the age of 3-5 years, it disappears or transforms into other syndromes: most frequently cerebellar syndromes and developmental disintegrations (disintegration of the development of the CNS and medium-grade mental retardation). These groups overlap only little. From the hypotonic syndrome also the spastic syndrome or minor cerebral syndromes may develop. CIHS has, similarly as some other manifestations of CNS affections, multiple causes. One of them is most probably a defect of or lack of development of facilitating pathways of gamma fibres from the cerebellum or possibly from the reticular formation of the brain stem to the spinal cord; another probable cause is longer immaturity of the afferent system (which leads finally to developmental disintegration). It may be assumed that the facilitating systems of pathways develop later and are thus more immature and therefore more vulnerable. According to the latest information it seems that in CIHS also the muscular component participates as prenatal cerebral affections can cause myopathy with hypotonia.

  11. Central African Republic.

    PubMed

    1989-11-01

    The Central African Republic contains 242,000 square miles, which rolling terrain almost 2000 feet above sea level. The climate is tropical, and it has a population of 2.8 million people with a 2.5% growth rate. There are more than 80 ethnic groups including Baya 34%, Banda 28%, Sara 10%, Mandja 9%, Mboum 9%, and M'Baka 7%. The religions are traditional African 35%, protestant 25%, Roman Catholic 25%, and Muslim 15%, and the languages are French and Sangho. The infant mortality rate is 143/1000, with expectancy at 49 years and a 40% literacy rate. The work force of 1 million is 70% agricultural, industry 6% and commerce and service 6% and government 3%. The government consists of a president assisted by cabinet ministers and a single party. Natural resources include diamonds, uranium, timber, gold, and oil, and major industries are beverages, textiles, and soap. Agricultural products feature coffee, cotton, peanuts, tobacco, food crops and livestock. Most of the population live in rural areas and most of the 80 ethnic groups have their own language. This is one of the world's least developed countries, with a per capita income of $375/year. The main problems with development are the poor transportation infrastructure, and the weak internal and international marketing systems. The US and various international organizations have aided in agriculture development, health programs, and family planning. US investment is mainly in diamond and gold mining, and although oil drilling has been successful it is not economically feasible at current prices.

  12. Recurrent central neurocytomas.

    PubMed

    Bertalanffy, Alexander; Roessler, Karl; Koperek, Oskar; Gelpi, Ellen; Prayer, Daniela; Knosp, Engelbert

    2005-07-01

    Since the first description of Central neurocytomas (CNs) as a benign tumor entity in 1982, there has been great enthusiasm regarding the benign course and the curative surgical approach to this disease. The current study was performed to investigate the frequency of disease recurrence during long-term follow-up. A retrospective analysis of the medical files with emphasis on clinicoradiologic findings and histologic and immunohistochemical features was performed. Between 1985-2003. surgical resection was performed in 14 patients with CNs ages 16-43 years (7 were female and 7 were male). Two patients (14%) died postoperatively and one patient had a malignant disease course (7%). In the remaining 11 patients, one patient with an incompletely resected CN had disease progression after 37 months but at the time of last follow-up had had stable disease for 10 years. In addition, the authors reported 5 patients with disease recurrence occurring at a median of 67 months after surgery (range, 51-79 months after surgery), all of which occurred after complete surgical resection was performed. The observation period for the remaining 5 patients was short (median of 34 months [range, 5-44 months]). Extensive histologic and immunohistochemical workup did not identify any significant prognostic parameters. The MIB-1 proliferation index ranged from 0.8-11% (median of 4.6%), but was reported to be 46.8% in the malignant transformed tumor. All patients with disease recurrence responded well to different forms of focal radiation therapy (gamma knife radiosurgery in three patients and interstitial irradiation in one patient) and for one patient with a recently detected recurrence, gamma knife radiosurgery was planned. CNs appear to have a higher tendency to recur during long-term follow-up than previously reported, even after complete resection. Therefore, periodic neuroradiologic follow-up examinations should be considered mandatory in all patients, even after several years.

  13. Central and southern Africa

    SciTech Connect

    McGrew, H.J.

    1981-10-01

    Exploration in central and southern Africa continued to expand during 1980. The greatest concentration of activity was in Nigeria. However, there was considerable increase in the level of exploratory work in Cameroon and Congo. Significant new finds have been made in Ivory Coast. Geological and geophysical activity was carried out in 18 of the countries, with those in the western part having the largest share. Seismic work involved 225 party months of operation. Most of this time was spent on land, but marine operations accounted for 73,389 km of new control. Gravity and magnetic data were recorded during the marine surveys, and several large aeromagnetic projects were undertaken to obtain a total of 164,498 line km of data. Exploratory and development drilling accounted for a total of 304 wells and 2,605,044 ft (794,212 m) of hole. The 92 exploratory wells that were drilled resulted in 47 oil and gas discoveries. In development drilling 89% of the 212 wells were successful. At the end of the year, 27 exploratory wells were underway, and 34 development wells were being drilled for a total of 61. Oil production from the countries that this review covers was 918,747,009 bbl in 1980, a drop of about 9% from the previous year. Countries showing a decline in production were Nigeria, Gabon, Cabinda, and Zaire. Increases were recorded in Cameroon, Congo, and Ghana. A new country was added to the list of producers when production from the Belier field in Ivory Coast came on stream. 33 figures, 15 tables.

  14. Recursion Formulas of Central Configurations.

    NASA Astrophysics Data System (ADS)

    Tien, Fangcheng

    1993-01-01

    This paper analyzes central configurations which are special configurations leading to homothetic solutions of the n-body problem. For the planar central configurations, these solutions also provide periodic solutions of the n-body problem. Chapter 1 defines the problem and provides an overview of the area. There is historical interest in knowing the total number of these central configurations. For n >= 4 the problem remains unsolved. Furthermore, a different mass ratio between the n bodies will produce a different total number of central configurations. This paper will provide the total number of central configurations which has a special mass ratio. For the planar central configurations the total number of central configurations grows at the speed n!2n, and the three dimensional case is n!3^{n }. Chapters 2, 3 and 5 give details and proofs of the analytical continuation method. This method begins with three bodies, then creates the central configurations with four bodies with one small mass, using the implicit function theorem. If the process is repeated, the total number of central configurations for any n-body problem may be calculated, provided (n-3) masses are sufficiently small. In Chapters 4 and 7, the formulas are derived for the total number of central configurations of the n-body problem with special mass ratio (m _1,m_2,m_3,epsilon_1, ...,epsilonn) in both planar and three-dimensional cases. Examples of formulas provided are: n!(2^{n+1} + 1) , n!((n^2 - n + 4)2^{n+1 } - n - 7), and (n!/6) ((n ^3 + 11n - 12)2^{n+2} + 6n + 54). Chapter 6 solves a very special degenerate case during the continuation process. The Morse Index of these central configurations is discussed in Chapter 8.

  15. Central control of body temperature

    PubMed Central

    Morrison, Shaun F.

    2016-01-01

    Central neural circuits orchestrate the behavioral and autonomic repertoire that maintains body temperature during environmental temperature challenges and alters body temperature during the inflammatory response and behavioral states and in response to declining energy homeostasis. This review summarizes the central nervous system circuit mechanisms controlling the principal thermoeffectors for body temperature regulation: cutaneous vasoconstriction regulating heat loss and shivering and brown adipose tissue for thermogenesis. The activation of these thermoeffectors is regulated by parallel but distinct efferent pathways within the central nervous system that share a common peripheral thermal sensory input. The model for the neural circuit mechanism underlying central thermoregulatory control provides a useful platform for further understanding of the functional organization of central thermoregulation, for elucidating the hypothalamic circuitry and neurotransmitters involved in body temperature regulation, and for the discovery of novel therapeutic approaches to modulating body temperature and energy homeostasis. PMID:27239289

  16. Controlling centrality in complex networks

    PubMed Central

    Nicosia, V.; Criado, R.; Romance, M.; Russo, G.; Latora, V.

    2012-01-01

    Spectral centrality measures allow to identify influential individuals in social groups, to rank Web pages by popularity, and even to determine the impact of scientific researches. The centrality score of a node within a network crucially depends on the entire pattern of connections, so that the usual approach is to compute node centralities once the network structure is assigned. We face here with the inverse problem, that is, we study how to modify the centrality scores of the nodes by acting on the structure of a given network. We show that there exist particular subsets of nodes, called controlling sets, which can assign any prescribed set of centrality values to all the nodes of a graph, by cooperatively tuning the weights of their out-going links. We found that many large networks from the real world have surprisingly small controlling sets, containing even less than 5 – 10% of the nodes. PMID:22355732

  17. North Central Thailand

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This radar image shows the dramatic landscape in the Phang Hoei Range of north central Thailand, about 40 kilometers (25 miles) northeast of the city of Lom Sak. The plateau, shown in green to the left of center, is the area of Phu Kradung National Park. This plateau is a remnant of a once larger plateau, another portion of which is seen along the right side of the image. The plateaus have been dissected by water erosion over thousands of years. Forest areas appear green on the image; agricultural areas and settlements appear as red and blue. North is toward the lower right. The area shown is 38 by 50 kilometers (24 by 31 miles) and is centered at 16.96 degrees north latitude, 101.67 degrees east longitude. Colors are assigned to different radar frequencies and polarizations as follows: red is L-band horizontally transmitted and horizontally received; green is L-band horizontally transmitted and vertically received; blue is C-band horizontally transmitted and vertically received. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture (SIR-C/X-SAR) imaging radar on October 3, 1994, when it flew aboard the space shuttle Endeavour. SIR-C/X-SAR is a joint mission of the U.S./German and Italian space agencies.

    Spaceborne Imaging Radar-C and X-Band Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves allowing detailed observations at any time, regardless of weather or sunlight conditions. SIR-C/X-SAR uses three microwave wavelengths: L-band (24 cm), C-band (6 cm) and X-band (3 cm). The multi-frequency data will be used by the international scientific community to better understand the global environment and how it is changing. The SIR-C/X-SAR data, complemented by aircraft and ground studies, will give scientists clearer insights into those environmental changes which are caused by nature and those changes which are induced by human activity. SIR-C was developed by

  18. North Central Thailand

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This radar image shows the dramatic landscape in the Phang Hoei Range of north central Thailand, about 40 kilometers (25 miles) northeast of the city of Lom Sak. The plateau, shown in green to the left of center, is the area of Phu Kradung National Park. This plateau is a remnant of a once larger plateau, another portion of which is seen along the right side of the image. The plateaus have been dissected by water erosion over thousands of years. Forest areas appear green on the image; agricultural areas and settlements appear as red and blue. North is toward the lower right. The area shown is 38 by 50 kilometers (24 by 31 miles) and is centered at 16.96 degrees north latitude, 101.67 degrees east longitude. Colors are assigned to different radar frequencies and polarizations as follows: red is L-band horizontally transmitted and horizontally received; green is L-band horizontally transmitted and vertically received; blue is C-band horizontally transmitted and vertically received. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture (SIR-C/X-SAR) imaging radar on October 3, 1994, when it flew aboard the space shuttle Endeavour. SIR-C/X-SAR is a joint mission of the U.S./German and Italian space agencies.

    Spaceborne Imaging Radar-C and X-Band Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves allowing detailed observations at any time, regardless of weather or sunlight conditions. SIR-C/X-SAR uses three microwave wavelengths: L-band (24 cm), C-band (6 cm) and X-band (3 cm). The multi-frequency data will be used by the international scientific community to better understand the global environment and how it is changing. The SIR-C/X-SAR data, complemented by aircraft and ground studies, will give scientists clearer insights into those environmental changes which are caused by nature and those changes which are induced by human activity. SIR-C was developed by

  19. Significance of detrital zircons in upper Devonian ocean-basin strata of the Sonora allochthon and Lower Permian synorogenic strata of the Mina Mexico foredeep, central Sonora, Mexico

    USGS Publications Warehouse

    Poole, F.G.; Gehrels, G.E.; Stewart, John H.

    2008-01-01

    U-Pb isotopic dating of detrital zircons from a conglomeratic barite sandstone in the Sonora allochthon and a calciclastic sandstone in the Mina Mexico foredeep of the Minas de Barita area reveals two main age groups in the Upper Devonian part of the Los Pozos Formation, 1.73-1.65 Ga and 1.44-1.42 Ga; and three main age groups in the Lower Permian part of the Mina Mexico Formation, 1.93-1.91 Ga, 1.45-1.42 Ga, and 1.1-1.0 Ga. Small numbers of zircons with ages of 2.72-2.65 Ga, 1.30-1.24 Ga, ca. 2.46 Ga, ca. 1.83 Ga, and ca. 0.53 Ga are also present in the Los Pozos sandstone. Detrital zircons ranging in age from 1.73 to 1.65 Ga are considered to have been derived from the Yavapai, Mojave, and Mazatzal Provinces and their transition zones of the southwestern United States and northwestern Mexico. The 1.45-1.30 Ga detrital zircons were probably derived from scattered granite bodies within the Mojave and Mazatzal basement rocks in the southwestern United States and northwestern Mexico, and possibly from the Southern and Eastern Granite-Rhyolite Provinces of the southern United States. The 1.24-1.0 Ga detrital zircons are believed to have been derived from the Grenville (Llano) Province to the east and northeast or from Grenvilleage intrusions or anatectites to the north. Several detrital zircon ages ranging from 2.72 to 1.91 Ga were probably derived originally from the Archean Wyoming Province and Early Paleoproterozoic rocks of the Lake Superior region. These older detrital zircons most likely have been recycled one or more times into the Paleozoic sandstones of central Sonora. The 0.53 Ga zircon is believed to have been derived from a Lower Cambrian granitoid or meta-morphic rock northeast of central Sonora, possibly in New Mexico and Colorado, or Oklahoma. Detrital zircon geochronology suggests that most of the detritus in both samples was derived from Laurentia to the north, whereas some detritus in the Permian synorogenic foredeep sequence was derived from the

  20. Centralized versus Decentralized Information Systems

    NASA Astrophysics Data System (ADS)

    Hugoson, Mats-Åke

    This paper brings into question whether information systems should be centralized or decentralized in order to provide greater support for different business processes. During the last century companies and organizations have used different approaches for centralization and decentralization; a simple answer to the question does not exist. This paper provides a survey of the evolution of centralized and decentralized approaches, mainly in a Nordic perspective. Based on critical reflections on the situation in the end of the century we can discuss what we can learn from history to achieve alignment between centralized and decentralized systems and the business structure. The conclusion is that theories, management and practice for decisions on centralization or decentralization of information systems must be improved. A conscious management and control of centralization /decentralization of IT support is a vital question in the company or the organization, and this is not a task that can be handled only by IT-specialists. There is a need for business oriented IT management of centralization/decentralization.

  1. Central Chemoreceptors: Locations and Functions

    PubMed Central

    Nattie, Eugene; Li, Aihua

    2016-01-01

    Central chemoreception traditionally refers to a change in ventilation attributable to changes in CO2/H+ detected within the brain. Interest in central chemoreception has grown substantially since the previous Handbook of Physiology published in 1986. Initially, central chemoreception was localized to areas on the ventral medullary surface, a hypothesis complemented by the recent identification of neurons with specific phenotypes near one of these areas as putative chemoreceptor cells. However, there is substantial evidence that many sites participate in central chemoreception some located at a distance from the ventral medulla. Functionally, central chemoreception, via the sensing of brain interstitial fluid H+, serves to detect and integrate information on 1) alveolar ventilation (arterial PCO2), 2) brain blood flow and metabolism and 3) acid-base balance, and, in response, can affect breathing, airway resistance, blood pressure (sympathetic tone) and arousal. In addition, central chemoreception provides a tonic ‘drive’ (source of excitation) at the normal, baseline PCO2 level that maintains a degree of functional connectivity among brainstem respiratory neurons necessary to produce eupneic breathing. Central chemoreception responds to small variations in PCO2 to regulate normal gas exchange and to large changes in PCO2 to minimize acid-base changes. Central chemoreceptor sites vary in function with sex and with development. From an evolutionary perspective, central chemoreception grew out of the demands posed by air vs. water breathing, homeothermy, sleep, optimization of the work of breathing with the ‘ideal’ arterial PCO2, and the maintenance of the appropriate pH at 37°C for optimal protein structure and function. PMID:23728974

  2. Centralized digital control of accelerators

    SciTech Connect

    Melen, R.E.

    1983-09-01

    In contrasting the title of this paper with a second paper to be presented at this conference entitled Distributed Digital Control of Accelerators, a potential reader might be led to believe that this paper will focus on systems whose computing intelligence is centered in one or more computers in a centralized location. Instead, this paper will describe the architectural evolution of SLAC's computer based accelerator control systems with respect to the distribution of their intelligence. However, the use of the word centralized in the title is appropriate because these systems are based on the use of centralized large and computationally powerful processors that are typically supported by networks of smaller distributed processors.

  3. The CDF Central Outer Tracker

    SciTech Connect

    Pitts, K.T.; CDF Collaboration

    1997-01-01

    We describe the CDF Central Outer Tracker (COT), an open-cell drift chamber currently being constructed for the CDF detector to run at the upgraded Fermilab Tevatron collider. This detector will provide central tracking with excellent momentum resolution in the high- density environment of a hadron collider. It will be able to resolve 132 ns beam crossings and provide tracking trigger information to the Level 1 trigger. The design is based upon the existing and successful CDF Central Tracking Chamber. The preliminary mechanical and electrical designs are presented. 5 refs., 5 figs., 1 tab.

  4. Demographic tensions in Central America.

    PubMed

    1986-08-01

    This discussion of Central America focuses on the rapid growth of its population, its stagnating economy, and those countries that are socioeconomically advanced. Between 1950-85 the population of Central America tripled, from 9.1 million to 26. 4 million, due to marked mortality declines and the absence of off-setting fertility declines. The distribution of Central Americas's growing populations sets its population growth apart from that of other developing regions. Currently, almost half of all Central Americans live in cities. Although the average growth rate for Central American countries has fallen and is expected to drop further, the decline does not counterbalance the effect of the absolute rise in population numbers. The average annual growth rate of more than 3% annually in the 1960s fell to about 2.6% in recent years, but this decline is due primarily to socioeconomically advanced Costa Rica and Panama. Central America's age structure further complicates the population crisis. About 43% of Central Americans are under the age of 15. When the increasingly larger young population group enters it reproductive years, the potential for future growth (albeit the falling rate of population increase) is unparalleled. UN population projections show the region's population at 40 million by the year 2000. The 1973 oil crisis began a downward spiral for the buoyant post World War II Central American economy. Between 1950-79, real per capita income growth in Central America doubled, with Central American economies growing an average of 5.3% annually. By the early 1980s, overseas markets of the trade-dependent countries of Central America had dried up due to protectionism abroad and slumping basic commodity prices. These and other factors plunged Central America into its current economic malaise of falling real per capita income, rising unemployment, curtailed export led economic growth, and a rising cost of living. In general, economic growth in Central America

  5. Central-Office Real Estate.

    ERIC Educational Resources Information Center

    Pardini, Priscilla

    2003-01-01

    Describes how to upgrade a school district's central-office facilities without incurring taxpayer enmity. Includes case studies from Harford County, Maryland; Orange and Broward Counties, Florida; South Milwaukee, Wisconsin; Mt. Baker, Washington; Chicago, Illinois; and Rochester, New Hampshire. (PKP)

  6. Super Kitchen Centralizes Food Service

    ERIC Educational Resources Information Center

    Modern Schools, 1975

    1975-01-01

    To centralize food service within the entire Pittsburgh school district, a 90,000-square-foot food service preparation building contains cranes and monorails to move 500-pound capacity vats throughout the kitchen. (Author/MLF)

  7. Central Fan Integrated Ventilation Systems

    SciTech Connect

    2009-05-12

    This information sheet describes one example of a ventilation system design, a central fan integrated supply (CFIS) system, a mechanical ventilation and pollutant source control to ensure that there is reasonable indoor air quality inside the house.

  8. The Centrality of Media Economics.

    ERIC Educational Resources Information Center

    Gomery, Douglas

    1993-01-01

    Argues that the study of media economics should stand at the core of the field of communication. Describes central concerns to be addressed, such as economic influence and effect, economic structure and conduct, and analysis of performance. (SR)

  9. Solitary median maxillary central incisor.

    PubMed

    Bolan, Michele; Derech, Carla D'Agostini; Ribeiro, Gerson Luiz Ulema; Pereira, Eliana Ternes; Almeida, Izabel Cristina Santos

    2009-01-01

    Solitary median maxillary central incisor syndrome (SMMCIS) is a rare abnormality characterized by the presence of a central incisor positioned at the maxillary mid-axis. This morphologic defect also can be associated with other diseases. The purpose of this paper was to present a case report of a 4-year-old twin child with SMMCIS. The patient showed a symmetrical primary maxillary central incisor located at the midline, with an absence of labial frenulum, an indistinct philtrum, and an incisive papilla. Radiographic examination confirmed the presence of only a maxillary central incisor in both dentitions. The patient was referred for a genetic and otolaryngological assessment, however, no other abnormality than the ones reported were detected.

  10. Central-Office Real Estate.

    ERIC Educational Resources Information Center

    Pardini, Priscilla

    2003-01-01

    Describes how to upgrade a school district's central-office facilities without incurring taxpayer enmity. Includes case studies from Harford County, Maryland; Orange and Broward Counties, Florida; South Milwaukee, Wisconsin; Mt. Baker, Washington; Chicago, Illinois; and Rochester, New Hampshire. (PKP)

  11. Peripherally inserted central catheter - insertion

    MedlinePlus

    ... nontunneled central venous catheters. In: Mauro MA, Murphy KPJ, Thomson KR, et al., eds. Image-Guided Interventions . ... by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is ...

  12. CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY

    SciTech Connect

    BERGMAN, T. B.; STEFANSKI, L. D.; SEELEY, P. N.; ZINSLI, L. C.; CUSACK, L. J.

    2012-09-19

    THE CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY WAS CONDUCTED TO DEVELOP AN OPTIMAL SEQUENCE OF REMEDIATION ACTIVITIES IMPLEMENTING THE CERCLA DECISION ON THE CENTRAL PLATEAU. THE STUDY DEFINES A SEQUENCE OF ACTIVITIES THAT RESULT IN AN EFFECTIVE USE OF RESOURCES FROM A STRATEGIC PERSPECTIVE WHEN CONSIDERING EQUIPMENT PROCUREMENT AND STAGING, WORKFORCE MOBILIZATION/DEMOBILIZATION, WORKFORCE LEVELING, WORKFORCE SKILL-MIX, AND OTHER REMEDIATION/DISPOSITION PROJECT EXECUTION PARAMETERS.

  13. Rosette Central Configurations, Degenerate Central Configurations and Bifurcations

    NASA Astrophysics Data System (ADS)

    Lei, J.; Santoprete, M.

    2006-03-01

    In this paper we find a class of new degenerate central configurations and bifurcations in the Newtonian n-body problem. In particular we analyze the Rosette central configurations, namely a coplanar configuration where n particles of mass m 1 lie at the vertices of a regular n-gon, n particles of mass m 2 lie at the vertices of another n-gon concentric with the first, but rotated of an angle π / n, and an additional particle of mass m 0 lies at the center of mass of the system. This system admits two mass parameters μ = m 0/ m 1 and ɛ = m 2/ m 1. We show that, as μ varies, if n > 3, there is a degenerate central configuration and a bifurcation for every ɛ > 0, while if n = 3 there is a bifurcation only for some values of ɛ.

  14. Coverage centralities for temporal networks*

    NASA Astrophysics Data System (ADS)

    Takaguchi, Taro; Yano, Yosuke; Yoshida, Yuichi

    2016-02-01

    Structure of real networked systems, such as social relationship, can be modeled as temporal networks in which each edge appears only at the prescribed time. Understanding the structure of temporal networks requires quantifying the importance of a temporal vertex, which is a pair of vertex index and time. In this paper, we define two centrality measures of a temporal vertex based on the fastest temporal paths which use the temporal vertex. The definition is free from parameters and robust against the change in time scale on which we focus. In addition, we can efficiently compute these centrality values for all temporal vertices. Using the two centrality measures, we reveal that distributions of these centrality values of real-world temporal networks are heterogeneous. For various datasets, we also demonstrate that a majority of the highly central temporal vertices are located within a narrow time window around a particular time. In other words, there is a bottleneck time at which most information sent in the temporal network passes through a small number of temporal vertices, which suggests an important role of these temporal vertices in spreading phenomena. Contribution to the Topical Issue "Temporal Network Theory and Applications", edited by Petter Holme.Supplementary material in the form of one pdf file available from the Journal web page at http://dx.doi.org/10.1140/epjb/e2016-60498-7

  15. Inferring Centrality from Network Snapshots

    NASA Astrophysics Data System (ADS)

    Shao, Haibin; Mesbahi, Mehran; Li, Dewei; Xi, Yugeng

    2017-01-01

    The topology and dynamics of a complex network shape its functionality. However, the topologies of many large-scale networks are either unavailable or incomplete. Without the explicit knowledge of network topology, we show how the data generated from the network dynamics can be utilised to infer the tempo centrality, which is proposed to quantify the influence of nodes in a consensus network. We show that the tempo centrality can be used to construct an accurate estimate of both the propagation rate of influence exerted on consensus networks and the Kirchhoff index of the underlying graph. Moreover, the tempo centrality also encodes the disturbance rejection of nodes in a consensus network. Our findings provide an approach to infer the performance of a consensus network from its temporal data.

  16. Central Hyperthermia Treated with Bromocriptine

    PubMed Central

    Natteru, P.; George, P.; Bell, R.; Nattanmai, P.

    2017-01-01

    Introduction. Central hyperthermia is common in patients with brain injury. It typically has a rapid onset with high temperatures and marked fluctuations and responds poorly to antibiotics and antipyretics. It is also associated with worse outcomes in the brain injured patient. Recognizing this, it is important to aggressively manage it. Case Report. We report a 34-year-old male with a right thalamic hemorrhage extending to the midbrain and into the ventricles. During his admission, he developed intractable fevers with core temperatures as high as 39.3°C. Infectious workup was unremarkable. The fever persisted despite empiric antibiotics, antipyretics, and cooling wraps. Bromocriptine was started resulting in control of the central hyperthermia. The fever spikes were reduced to minor fluctuations that significantly worsened with any attempt to wean off the bromocriptine. Conclusion. Diagnosing and managing central hyperthermia can be challenging. The use of bromocriptine can be beneficial as we have reported. PMID:28348904

  17. Inferring Centrality from Network Snapshots

    PubMed Central

    Shao, Haibin; Mesbahi, Mehran; Li, Dewei; Xi, Yugeng

    2017-01-01

    The topology and dynamics of a complex network shape its functionality. However, the topologies of many large-scale networks are either unavailable or incomplete. Without the explicit knowledge of network topology, we show how the data generated from the network dynamics can be utilised to infer the tempo centrality, which is proposed to quantify the influence of nodes in a consensus network. We show that the tempo centrality can be used to construct an accurate estimate of both the propagation rate of influence exerted on consensus networks and the Kirchhoff index of the underlying graph. Moreover, the tempo centrality also encodes the disturbance rejection of nodes in a consensus network. Our findings provide an approach to infer the performance of a consensus network from its temporal data. PMID:28098166

  18. MRDIS Standalone Central Alarm Station

    SciTech Connect

    2012-09-12

    The MRDIS Standalone Central Alarm Station(MRDIS-CAS} is a software system for receiving, storing, and reviewing radiation data collected by the Mobile Radiation Detection and Identification System (MRDIS}, a mobile radiation scanning system developed for use in foreign ports for the DOE Megaports Initiative. It is designed to run on one of the on board computers in the MRDIS cab. It will collect, store, and display data from the MRDIS without the need for wireless communications or centralized server technology. It is intended to be a lightweight replacement for a distributed Megaports communication system in ports where the necessary communications infrastructure does not exist for a full Megaports communications system.

  19. Geothermal activities in Central America

    SciTech Connect

    Whetten, J.T.; Hanold, R.J.

    1985-09-11

    The Agency for International Development is funding a new program in energy and minerals for Central America. Geothermal energy is an important component. A country-wide geothermal assessment has started in Honduras, and other assessment activities are in progress or planned for Costa Rica, El Salvador, Guatemala, and Panama. Instrumentation for well logging has been provided to Costa Rica, and a self-contained logging truck will be made available for use throughout Central America. An important objective of this program is to involve the private sector in resource development. 4 refs., 3 figs.

  20. Fire management in central America

    Treesearch

    Andrea L. Koonce; Armando González-Cabán

    1992-01-01

    Information on fire management operations in Central America is scant. To evaluate the known level of fire occurrence in seven countries in that area, fire management officers were asked to provide information on their fire control organizations and on any available fire statistics. The seven countries surveyed were Guatemala, Belize, Honduras, El Salvador, Nicaragua,...

  1. The Centrality of Ethical Leadership

    ERIC Educational Resources Information Center

    Ehrich, Lisa C.; Harris, Jessica; Klenowski, Val; Smeed, Judy; Spina, Nerida

    2015-01-01

    Purpose: The central argument in this paper is that ethical school leadership is imperative in a context of increasing performance-driven accountability. The purpose of this paper is to focus on school principals' perceptions of how they understand ethical leadership and how they lead the ethical use of data. Design/Methodology/Approach: This…

  2. Putting Central Registers to Work

    ERIC Educational Resources Information Center

    Besharov, Douglas J.

    1977-01-01

    Cites shortcomings of existing centralized state systems for processing child protection case records. Diagnostic, monitoring and statistical functions of these registers are described as severely limited by inaccurate and incomplete reporting. Confidentiality of records, subjects' access to records and problems of verification are discussed. (BF)

  3. Central Statistical Libraries in Europe.

    ERIC Educational Resources Information Center

    Kaiser, Lisa

    The paper tries to clarify the position special governmental libraries hold in the system of libraries of today by investigating only one specific type of library mainly from a formal and historical point of view. Central statistical libraries in Europe were first regarded as administrative and archival libraries. Their early holdings of foreign…

  4. Earth Works Central. [Educational Packet].

    ERIC Educational Resources Information Center

    Kids for Saving Earth Worldwide, Minneapolis, MN.

    Earth Works Central is an educational curriculum tool designed to provide environmental education support for the classroom. It features environmental materials for science, geography, history, art, music, dramatics, and physical education. It includes information on creating an environmental center where kids can learn and become empowered to…

  5. Readability of Central Florida Newspapers.

    ERIC Educational Resources Information Center

    Olmstead, Phyllis M.

    A study analyzed the readability of seven central Florida newspapers (one of which is a college newspaper) and "USA Today.""Rightwriter," a grammar checker and readability computer program, was used to evaluate front page articles for each of the eight newspapers. The readability formulas invoked in the readability program…

  6. Central Asian Drug Trafficking Dilemma

    DTIC Science & Technology

    2003-12-01

    DRUG ADDICTION AND HIV/AIDS ........................................................18 G. UNITED STATES AND RUSSIA...throughout the area since the breakup. Heroin , opium, hashish, cocaine, and many other large-scale drugs have spread throughout the region in epidemic...The wider Central Asia region was experiencing a sharp rise in drug addiction . Tajikistan is not a major producer of narcotics, but is a major

  7. Despair at the Central Office.

    ERIC Educational Resources Information Center

    Tewel, Kenneth J.

    1995-01-01

    The psychological fallout of school restructuring can paralyze central office staff. Superintendents need effective incentives to keep people engaged in organization-building. They must create a trusting, risk-taking environment, develop a shared mission, empower staff to make decisions, provide learning opportunities, afford professional…

  8. Investing in the Central Office

    ERIC Educational Resources Information Center

    Shields, Regis Anne

    2010-01-01

    Benchmarking against similar districts, ideally higher-performing ones, can be a valuable tool for determining the appropriate level of central-office investment. Unfortunately, reliable benchmarks on district spending in teaching and learning support are not readily available. This should not preclude districts from using this valuable method to…

  9. Music Libraries: Centralization versus Decentralization.

    ERIC Educational Resources Information Center

    Kuyper-Rushing, Lois

    2002-01-01

    Considers the decision that branch libraries, music libraries in particular, have struggled with concerning a centralized location in the main library versus a decentralized collection. Reports on a study of the Association of Research Libraries that investigated the location of music libraries, motivation for the location, degrees offered,…

  10. The Centrality of Ethical Leadership

    ERIC Educational Resources Information Center

    Ehrich, Lisa C.; Harris, Jessica; Klenowski, Val; Smeed, Judy; Spina, Nerida

    2015-01-01

    Purpose: The central argument in this paper is that ethical school leadership is imperative in a context of increasing performance-driven accountability. The purpose of this paper is to focus on school principals' perceptions of how they understand ethical leadership and how they lead the ethical use of data. Design/Methodology/Approach: This…

  11. Grazing in central hardwood forests

    Treesearch

    Robert A. McQuilkin; Harold Scholten

    1989-01-01

    Woodland grazing is a major forestry and land management problem in parts of the central hardwood region. Most forest grazing is by cattle and, to a lesser extent, hogs in woodlands adjacent to pastures or feedlots. The practice is particularly common in the cattle producing areas of the Corn Belt where often 50 percent or more of the upland forest is grazed. Woodland...

  12. Illustrating the Central Limit Theorem

    ERIC Educational Resources Information Center

    Corcoran, Mimi

    2016-01-01

    Statistics is enjoying some well-deserved limelight across mathematics curricula of late. Some statistical concepts, however, are not especially intuitive, and students struggle to comprehend and apply them. As an AP Statistics teacher, the author appreciates the central limit theorem as a foundational concept that plays a crucial role in…

  13. Central Bureau Status and Perspective

    NASA Technical Reports Server (NTRS)

    Neilan, Ruth

    2004-01-01

    The Central Bureau continues to promote the IGS organization, data and data products as setting the world standard for GPS/GNSS geodetic applications as outlined in the IGS Strategic Plan. The Central Bureau was responsible for the organization of the strategic planning process, preparation of all documents, and the editing and publication of the plan. This was a major activity and the Board s consensus on the plan is a significant milestone in the evolution of the IGS. The Central Bureau is responsible for the day-to-day management of the Service. With 200 organizations in over 80 countries and a ground network of approx. 350 stations, this requires daily interfaces on many different levels globally. The separate summary of the IGS Network Coordinator is included in this annual report and demonstrates the vital technical tasks of the Central Bureau. The CB is also responsible to arrange and organize all Board activities and is involved in the supporting the planning and logistics of all IGS workshops and meetings.

  14. Chapter 1: Central Arizona Highlands

    Treesearch

    Peter F. Ffolliott

    1999-01-01

    The Central Arizona Highlands are a distinct biogeographic, climatic, and physiographic province that forms a diverse ecotone between the larger Colorado Plateau to the north and the Sonoran Desert ecoregions to the south (figure 1). The Highlands coincide approximately with the Arizona Transition Zone identified by ecologists, geologists and others. This region is one...

  15. Central configurations for -body problems

    NASA Astrophysics Data System (ADS)

    Zhao, Furong; Chen, Jian

    2015-01-01

    We show the existence of planar central configurations for -body problems with Newtonian potentials; in such configurations, -bodies are located at the vertices of regular -gons with a common center, where regular -gons are homothetic, and regular -gons are homothetic rotated by compared to the first set of -gons, and all masses on the same -gon are equal.

  16. The CMS central hadron calorimeter

    SciTech Connect

    Freeman, J.; E892 Collaboration

    1996-12-31

    The CMS central hadron calorimeter is a copper absorber/ scintillator sampling structure. We describe design choices that led us to this concept, details of the mechanical and optical structure, and test beam results. We discuss calibration techniques, and finally the anticipated construction schedule.

  17. Illustrating the Central Limit Theorem

    ERIC Educational Resources Information Center

    Corcoran, Mimi

    2016-01-01

    Statistics is enjoying some well-deserved limelight across mathematics curricula of late. Some statistical concepts, however, are not especially intuitive, and students struggle to comprehend and apply them. As an AP Statistics teacher, the author appreciates the central limit theorem as a foundational concept that plays a crucial role in…

  18. Forest statistics of central Kentucky

    Treesearch

    The Forest Survey Organization. Central States Forest Experiment Station

    1950-01-01

    This Survey Release presents the more significant preliminary statistics on the forest area and timber volume for each of the four regions of Central Kentucky. A similar report has been published for the Western Kentucky region and a release for the eastern region will be issued as soon as field work and tabulations are completed. Later an analytical report for the...

  19. Central America: A Regional Study.

    ERIC Educational Resources Information Center

    Mowry, George; Lacy, Ann

    This lesson is a series of activities and multi-media presentations designed to enable students to understand the historic and geographic roots of some of the problems that Central American nations have faced. Geography, history, writing, and storytelling are used as ways of understanding a multicultural world. Creative thinking and participation…

  20. Today's central receiver power plant

    NASA Astrophysics Data System (ADS)

    Alpert, D. J.; Kolb, G. J.; Chavez, J. M.

    1991-04-01

    For 15 years, the United States Department of Energy has worked with industry, both utilities and manufacturers, to develop the technology of solar central receiver power plants. In this type of plant, sunlight is concentrated by a field of sun-tracking mirrors, called heliostats, onto a centrally located receiver. The solar energy is collected in the form of a heated fluid, which is used to generate steam to power a conventional turbine generator. For a number of reasons, molten nitrate salt is now the preferred heat transfer fluid. Commercial plants will be sized between 100 and 200 MW. The impetus for developing central receivers comes from their unique advantages: (1) they produce clean, reliable, low-cost electricity; (2) they have practical energy storage that provides a high degree of dispatchability (annually up to 60 percent) - without fossil fuels; and (3) they are environmentally benign. Development efforts around the world have brought the technology to the brink of commercialization: The technical feasibility has been proven, and cost, performance, and reliability can be confidently predicted. Plans are currently being developed for the final steps toward commercial central receiver power plants.

  1. Central New York's New Workforce

    ERIC Educational Resources Information Center

    Center for an Urban Future, 2009

    2009-01-01

    Conducted in late 2008 in partnership with the Greater Syracuse Chamber of Commerce and the Mohawk Valley Chamber of Commerce, this is the largest survey ever taken of Central New York businesses regarding the English language skills of the area workforce. The online survey was emailed to several hundred local businesses; 126 responses were…

  2. Central Corneal Thickness in Children

    PubMed Central

    2011-01-01

    Objective To report the central corneal thickness (CCT) in healthy white, African-American, and Hispanic children from birth to 17 years of age. Design Prospective observational multicenter study. Central corneal thickness was measured with a hand-held contact pachymeter. Results Two thousand seventy-nine children were included in the study, with ages ranging from day of birth to 17 years. Included were 807 white, 494 Hispanic, and 474 African-American individuals, in addition to Asian, unknown and mixed race individuals. African-American children had thinner corneas on average than that of both white (p< .001) and Hispanic children (p< .001) by approximately 20 micrometers. Thicker median CCT was observed with each successive year of age from age 1 to 11 years, with year-to-year differences steadily decreasing and reaching a plateau after age 11 at 573 micrometers in white and Hispanic children and 551 micrometers in African-American children. For every 100 micrometers of thicker CCT measured, the intraocular pressure was 1.5 mmHg higher on average (p< 0.001). For every diopter of increased myopic refractive error (p< 0.001) CCT was 1 micrometer thinner on average. Conclusions Median CCT increases with age from 1 to 11 years with the greatest increase present in the youngest age groups. African-American children on average have thinner central corneas than white and Hispanic children, while white and Hispanic children demonstrate similar central corneal thickness. PMID:21911662

  3. Central American geologic map project

    SciTech Connect

    Dengo, G.

    1986-07-01

    During the Northeast Quadrant Panel meeting of the Circum-Pacific Map Project held in Mexico City, February 1985, Central American panel members proposed and adopted plans for compiling a geologic map of Central America, probably at a scale of 1:500,000. A local group with participants from each country was organized and coordinated by Rolando Castillo, director, Central American School of Geology, University of Costa Rica, for the geologic aspects, and Fernando Rudin, director, Geographic Institute of Costa Rica, for the topographic base. In 1956, the US Geological Survey published a geologic map of the region at a scale of 1:1 million. Subsequent topographic and geologic mapping projects have provided a large amount of new data. The entire area is now covered by topographic maps at a scale of 1:50,000, and these maps have been used in several countries as a base for geologic mapping. Another regional map, the Metallogenic Map of Central America (scale = 1:2 million), was published in 1969 by the Central American Research Institute for Industry (ICAITI) with a generalized but updated geologic base map. Between 1969 and 1980, maps for each country were published by local institutions: Guatemala-Belize at 1:500,000, Honduras at 1:500,000, El Salvador at 1:100,000, Nicaragua at 1:1 million, Costa Rica at 1:200,000, and Panama at 1:1 million. This information, in addition to that of newly mapped areas, served as the base for the Central American part of the Geologic-Tectonic Map of the Caribbean Region (scale = 1:2.5 million), published by the US Geological Survey in 1980, and also fro the Northeast Quadrant Maps of the Circum-Pacific Region. The new project also involves bathymetric and geologic mapping of the Pacific and Caribbean margins of the Central American Isthmus. A substantial amount of new information of the Middle America Trench has been acquired through DSDP Legs 67 and 84.

  4. 34 CFR 303.301 - Central directory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Central directory. 303.301 Section 303.301 Education....301 Central directory. (a) Each system must include a central directory of information about— (1... to contact, by telephone or letter, any of the sources listed in the directory. (c) The central...

  5. Network Centrality of Metro Systems

    PubMed Central

    Derrible, Sybil

    2012-01-01

    Whilst being hailed as the remedy to the world’s ills, cities will need to adapt in the 21st century. In particular, the role of public transport is likely to increase significantly, and new methods and technics to better plan transit systems are in dire need. This paper examines one fundamental aspect of transit: network centrality. By applying the notion of betweenness centrality to 28 worldwide metro systems, the main goal of this paper is to study the emergence of global trends in the evolution of centrality with network size and examine several individual systems in more detail. Betweenness was notably found to consistently become more evenly distributed with size (i.e. no “winner takes all”) unlike other complex network properties. Two distinct regimes were also observed that are representative of their structure. Moreover, the share of betweenness was found to decrease in a power law with size (with exponent 1 for the average node), but the share of most central nodes decreases much slower than least central nodes (0.87 vs. 2.48). Finally the betweenness of individual stations in several systems were examined, which can be useful to locate stations where passengers can be redistributed to relieve pressure from overcrowded stations. Overall, this study offers significant insights that can help planners in their task to design the systems of tomorrow, and similar undertakings can easily be imagined to other urban infrastructure systems (e.g., electricity grid, water/wastewater system, etc.) to develop more sustainable cities. PMID:22792373

  6. Public water supplies in central and north-central Texas

    USGS Publications Warehouse

    Sundstrom, Raymond W.; Broadhurst, W.L.; Dwyer, B.C.

    1949-01-01

    This report gives a summarized description of the public water supplies in 35 counties of central and north-central Texas, extending from the southern boundaries of Travis, Blanco, Gillespie, and Kerr Counties northward to the TexasOklahoma State line. It gives the available data as follows for each of the 145 communities: Population of the community; name of the official from whom the information was obtained; ownership of water works, whether private or municipal source of supply, whether ground water or surface water; the amount of water consumed; the facilities for storage; the number of customers served; the character of the chemical and sanitary treatment, if any; and chemical analyses of the water. Where ground water is used, the following is also given: Records of wells, including drillers' logs; character of the pumping equipment; yields of the wells, and records of water levels, if available.

  7. Is Central Asia really exsiccating?

    NASA Astrophysics Data System (ADS)

    Aizen, V. B.; Aizen, E. M.; Surazakov, A. B.

    2008-12-01

    At the end of 20th and the beginning of 21st century central Asia oases suffered from serious drought caused lack of water for agriculture, economy growth and population increase. However, people of this region always experienced lack of water for irrigation and fought a war over the rights to control river streams. The drying up of central Asian rivers is not a new phenomenon according to the ancient manuscripts. Thus, lets see about what has happened with the past century climate and water resources of central Asia using the long-term observational data. We analyzed data from more than 200 meteorological stations and stream gauges over the central Asia in elevation range from 25 m. b.s.l. to 4,000 m. a.s.l. to understand the last 100 years variability in climate and water resources, examining changes in the extreme and mean monthly air temperatures, precipitation and river runoff. The evaluation of seasonal snow and glacier's covered areas between 1970th and 2007th in central Asia derived from AVHRR, MODIS, Hexagon KH-9, Landsat ETM and ASTER data exhibit 15% reduction of the seasonal snow covered area and 10.1% of the glacier area. It has been found that during last twenty years the duration of snowmelt, from the date of maximum snow cover to date of its disappearance, reduced by 30 days and in 2007 was equal to 138 days in the central Asian mountains. The decrease of seasonal snow cover is not a linear process. The further decrease may be accelerated due to increase of rainfall instead of snowfall in early spring months at high elevations, and consequently a lesser heat expenditure for the snowmelt. The growth in summer air temperatures, especially observable since the 1970th, accompanied by increase of evapotranspiration and precipitation, notably in summer and autumn, and at high elevations over 3,000 m, and at the western peripheral mountain ridges. Average difference in the means of annual air temperatures for the two thirty-year periods before and after

  8. The Bivariate Central Normal Distribution

    NASA Astrophysics Data System (ADS)

    Pratikno, B.; Jajang; Putri, A. C. C.; Haryono, Y. W. W.

    2017-04-01

    The research studied Probability Density Function (pdf), Cumulative Distribution Function (CDF) and graphical analysis of the bivariate central normal distribution. The CDF of this distribution is then used to compute power of the test Pre-Test-Test (PTT) in the testing intercept. The tables and graphs of the pdf (and CDF) of the bivariate central normal distribution (BCND) and power of the test in testing intercept are produced using R-code. The results showed that the mean and coefficient correlation have a significant affect on the curve, but the variance is not. The curves tend to be leptokurtic for small coefficient correlation, and they will be mesocurtic for large coefficient correlation. The power of the PTT increases as the CDF of the BCND increases.

  9. The Central Valley Hydrologic Model

    NASA Astrophysics Data System (ADS)

    Faunt, C.; Belitz, K.; Hanson, R. T.

    2009-12-01

    Historically, California’s Central Valley has been one of the most productive agricultural regions in the world. The Central Valley also is rapidly becoming an important area for California’s expanding urban population. In response to this competition for water, a number of water-related issues have gained prominence: conjunctive use, artificial recharge, hydrologic implications of land-use change, subsidence, and effects of climate variability. To provide information to stakeholders addressing these issues, the USGS made a detailed assessment of the Central Valley aquifer system that includes the present status of water resources and how these resources have changed over time. The principal product of this assessment is a tool, referred to as the Central Valley Hydrologic Model (CVHM), that simulates surface-water flows, groundwater flows, and land subsidence in response to stresses from human uses and from climate variability throughout the entire Central Valley. The CVHM utilizes MODFLOW combined with a new tool called “Farm Process” to simulate groundwater and surface-water flow, irrigated agriculture, land subsidence, and other key processes in the Central Valley on a monthly basis. This model was discretized horizontally into 20,000 1-mi2 cells and vertically into 10 layers ranging in thickness from 50 feet at the land surface to 750 feet at depth. A texture model constructed by using data from more than 8,500 drillers’ logs was used to estimate hydraulic properties. Unmetered pumpage and surface-water deliveries for 21 water-balance regions were simulated with the Farm Process. Model results indicate that human activities, predominately surface-water deliveries and groundwater pumping for irrigated agriculture, have dramatically influenced the hydrology of the Central Valley. These human activities have increased flow though the aquifer system by about a factor of six compared to pre-development conditions. The simulated hydrology reflects spatial

  10. A centralized audio presentation manager

    SciTech Connect

    Papp, A.L. III; Blattner, M.M.

    1994-05-16

    The centralized audio presentation manager addresses the problems which occur when multiple programs running simultaneously attempt to use the audio output of a computer system. Time dependence of sound means that certain auditory messages must be scheduled simultaneously, which can lead to perceptual problems due to psychoacoustic phenomena. Furthermore, the combination of speech and nonspeech audio is examined; each presents its own problems of perceptibility in an acoustic environment composed of multiple auditory streams. The centralized audio presentation manager receives abstract parameterized message requests from the currently running programs, and attempts to create and present a sonic representation in the most perceptible manner through the use of a theoretically and empirically designed rule set.

  11. Central exclusive production at RHIC

    SciTech Connect

    Adamczyk, Leszek; Guryn, Włodek; Turnau, Jacek

    2014-11-10

    The present status and future plans of the physics program of Central Exclusive Production (CEP) at RHIC are described. The measurements are based on the detection of the forward protons from the Double Pomeron Exchange (DPE) process in the Roman Pot system and of the recoil system of charged particles from the DPE process measured in the STAR experiment’s Time Projection Chamber (TPC). The data described here were taken using polarized proton-proton collisions at ps = 200 GeV. The preliminary spectra of two pion and four pion invariant mass reconstructed by STAR TPC in central region of pseudo-rapidity | | < 1, are presented. Near future plans to take data with the current system at center-of-mass energy ps = 200 GeV and plans to upgrade the forward proton tagging sys- tem are presented. Also a possible addition of the Roman Pots to the sPHENIX detector is discussed.

  12. [Central agenesis of the hand].

    PubMed

    Turki, Moez; Daghfous, Mehdi; Ennouri, Khalil; Khalfaoui, Faouzi; Baccari, Sayed; Tarhouni, Lamjed; Bahri, Hichem

    2002-06-01

    Central aplasia represent under 10% of congenital malformations of the hand. It is characterised by the partial or complete absence of the median ray. We adopted the classification of Swanson and considered this anomaly a stop of median longitudinal development. We separate 2 groups: Hand in folk: the aplasia interested only the median digits, all metacarpal are present. Hand in lobster's pincer: all median rays are absent including the metacarpal. We report a set of 16 children carriers of 23 central aplasia of the hand, it was about 14 hands in lobster'pincer and 9 hands in folk. In any case, the gene was merely aesthetic, the hand's function was complete. A child has been operated, and benefitted a closing of the median crack defect, he had a free thumb. For the other cases, abstention has been decided, indeed to close this cracks deprive these hands of a first corner the alone present.

  13. Central Nucleon-Nucleon Potential

    NASA Astrophysics Data System (ADS)

    Robilotta, M. R.

    2001-12-01

    The outer region of the NN interactions is dominated by the one pion exchange potential (OPEP), followed by the two-pion exchange potential (TPEP). Chiral calculations of the TPEP have been performed using either heavy baryon1 (HB) or relativistic2 perturbation theories. We compare the predictions from these two approaches for the dominant central interaction and show that they fail to agree by 25% ...

  14. Central collisions of heavy ions

    SciTech Connect

    Fung, Sun-yiu.

    1992-10-01

    This report describes the activities of the Heavy Ion Physics Group at the University of California, Riverside from October 1, 1991 to September 30, 1992. During this period, the program focused on particle production at AGS energies, and correlation studies at the Bevalac in nucleus-nucleus central collisions. As part of the PHENIX collaboration, contributions were made to the Preliminary Conceptual Design Report (pCDR), and work on a RHIC silicon microstrip detector R D project was performed.

  15. Tectonics of the central Andes

    NASA Technical Reports Server (NTRS)

    Bloom, Arthur L.; Isacks, Bryan L.; Fielding, Eric J.; Fox, Andrew N.; Gubbels, Timothy L.

    1989-01-01

    Acquisition of nearly complete coverage of Thematic Mapper data for the central Andes between about 15 to 34 degrees S has stimulated a comprehensive and unprecedented study of the interaction of tectonics and climate in a young and actively developing major continental mountain belt. The current state of the synoptic mapping of key physiographic, tectonic, and climatic indicators of the dynamics of the mountain/climate system are briefly reviewed.

  16. Geochronology Database for Central Colorado

    USGS Publications Warehouse

    Klein, T.L.; Evans, K.V.; deWitt, E.H.

    2010-01-01

    This database is a compilation of published and some unpublished isotopic and fission track age determinations in central Colorado. The compiled area extends from the southern Wyoming border to the northern New Mexico border and from approximately the longitude of Denver on the east to Gunnison on the west. Data for the tephrochronology of Pleistocene volcanic ash, carbon-14, Pb-alpha, common-lead, and U-Pb determinations on uranium ore minerals have been excluded.

  17. The CDF Central Analysis Farm

    SciTech Connect

    Kim, T.H.; Neubauer, M.; Sfiligoi, I.; Weems, L.; Wurthwein, F.; /UC, San Diego

    2004-01-01

    With Run II of the Fermilab Tevatron well underway, many computing challenges inherent to analyzing large volumes of data produced in particle physics research need to be met. We present the computing model within CDF designed to address the physics needs of the collaboration. Particular emphasis is placed on current development of a large O(1000) processor PC cluster at Fermilab serving as the Central Analysis Farm for CDF. Future plans leading toward distributed computing and GRID within CDF are also discussed.

  18. [Bases of central venous catheterization].

    PubMed

    Schmalz-Ott, Stéphane; Monti, Matteo; Vollenweider, Peter

    2008-10-29

    Central venous catheterization is a frequently performed procedure in internal medicine units. Residents in training frequently share the same questions, doubts and fears about this procedure : "Should I perform a subclavian catheterization in a patient with mild thrombopenia?"; "Which site has the lesser complication rate?"; "After how long does a catheter need to be replaced?". This mini-review of the current literature tries to answer this and other questions.

  19. Celtic Sites of Central Iberia

    NASA Astrophysics Data System (ADS)

    Pérez Gutiérrez, Manuel

    This chapter concerns the astronomy practiced by Celtic peoples in some parts of central Iberia, specifically the Vetton and Celtiberian peoples, inhabitants of the so-called Late Iron Age. The construction of some elements of religion or worship was perfectly determined by geometry, topography, and especially astronomy, because their spatial orientation occurs in locations of great interest for maintaining the local calendar. The maintenance of this calendar was probably the primary objective of some of the elements studied.

  20. Central Asia Active Fault Database

    NASA Astrophysics Data System (ADS)

    Mohadjer, Solmaz; Ehlers, Todd A.; Kakar, Najibullah

    2014-05-01

    The ongoing collision of the Indian subcontinent with Asia controls active tectonics and seismicity in Central Asia. This motion is accommodated by faults that have historically caused devastating earthquakes and continue to pose serious threats to the population at risk. Despite international and regional efforts to assess seismic hazards in Central Asia, little attention has been given to development of a comprehensive database for active faults in the region. To address this issue and to better understand the distribution and level of seismic hazard in Central Asia, we are developing a publically available database for active faults of Central Asia (including but not limited to Afghanistan, Tajikistan, Kyrgyzstan, northern Pakistan and western China) using ArcGIS. The database is designed to allow users to store, map and query important fault parameters such as fault location, displacement history, rate of movement, and other data relevant to seismic hazard studies including fault trench locations, geochronology constraints, and seismic studies. Data sources integrated into the database include previously published maps and scientific investigations as well as strain rate measurements and historic and recent seismicity. In addition, high resolution Quickbird, Spot, and Aster imagery are used for selected features to locate and measure offset of landforms associated with Quaternary faulting. These features are individually digitized and linked to attribute tables that provide a description for each feature. Preliminary observations include inconsistent and sometimes inaccurate information for faults documented in different studies. For example, the Darvaz-Karakul fault which roughly defines the western margin of the Pamir, has been mapped with differences in location of up to 12 kilometers. The sense of motion for this fault ranges from unknown to thrust and strike-slip in three different studies despite documented left-lateral displacements of Holocene and late

  1. Central auditory testing and dyslexia.

    PubMed

    Welsh, L W; Welsh, J J; Healy, M P

    1980-06-01

    A group of dyslexic pupils with normal end organ function was studied by a central auditory battery to determine whether a hearing disability existed. The clinical features of dyslexia are presented with emphasis on the psychological developmental and functional disorders associated with this reading problem. The central battery of Willeford was selected as the test medium and the results of the 77 dyslexic students were compared to the normative data. The model proposed by Sparks, et al., is accepted as the mechanism for dichotic audition. Reference is made to the organic basis of reading disorders from lesion in the calcarine area to the angular gyrus. The competing sentence test, binaural fusion, rapidly alternating speech perception, and filtered speech are described in detail and are organic foundation for the study. The authors indentified a high rate of failure in this investigation. Over 50% of the dyslexic students failed two of the four tests, and each of the 77 failed at least one component. The most sensitive tests were binaural fusion and filtered speech with less variation from the norm in the remaining two components. The effect of maturation in central audition was measured in each of the four tests. The data suggest: 1. the scores are lower in the early ages in each test; 2. that rapidly alternating speech and competing sentences approach the normal range albeit somewhat delayed; and 3. that binaural fusion and filtered speech improve in score somewhat but rather moderately and never approach the normal range. Based upon the central auditory data and in conjunction with the anatomical pathways of vision, the authors suggest the site of lesion to be in the temporo-parietal cortex and the association fibers.

  2. Volcanic hazards in Central America

    USGS Publications Warehouse

    Rose, William I.; Bluth, Gregg J.S.; Carr, Michael J.; Ewert, John W.; Patino, Lina C.; Vallance, James W.

    2006-01-01

    This volume is a sampling of current scientific work about volcanoes in Central America with specific application to hazards. The papers reflect a variety of international and interdisciplinary collaborations and employ new methods. The book will be of interest to a broad cross section of scientists, especially volcanologists. The volume also will interest students who aspire to work in the field of volcano hazards mitigation or who may want to work in one of Earth’s most volcanically active areas.

  3. Central corneal thickness in children.

    PubMed

    Bradfield, Yasmin S; Melia, B Michele; Repka, Michael X; Kaminski, Brett M; Davitt, Bradley V; Johnson, David A; Kraker, Raymond T; Manny, Ruth E; Matta, Noelle S; Weise, Katherine K; Schloff, Susan

    2011-09-01

    To determine the central corneal thickness (CCT) in healthy white, African American, and Hispanic children from birth to 17 years of age and to determine whether CCT varies by age, race, or ethnicity. Prospective observational multicenter study. Central corneal thickness was measured with a handheld contact pachymeter. A total of 2079 children were included in the study, with ages ranging from birth to 17 years. Included were 807 whites, 494 Hispanics, and 474 African Americans, in addition to Asian, unknown race, and mixed-race individuals. African American children had thinner corneas on average than that of both white and Hispanic children (P < .001 for both) by approximately 20 μm. Thicker median CCT was observed with each successive year of age from age 1 to 11 years, with year-to-year differences steadily decreasing and reaching a plateau after age 11 at 573 μm in white and Hispanic children and 551 μm in African American children. For every 100 μm of thicker CCT measured, the intraocular pressure was 1.5 mm Hg higher on average (P < .001). For every diopter of increased myopic refractive error, CCT was 1 μm thinner on average (P < .001). Median CCT increases with age from 1 to 11 years, with the greatest increase present in the youngest age groups. African American children on average have thinner central corneas than white and Hispanic children, whereas white and Hispanic children demonstrate similar CCT.

  4. Neuroimaging of central breathlessness mechanisms.

    PubMed

    Pattinson, Kyle T S; Johnson, Miriam J

    2014-09-01

    Breathlessness debilitates millions of people with cardiorespiratory conditions and cancer. Symptoms correlate poorly with the objective measures of disease (e.g. spirometry). Altered brain processing of respiratory sensations may contribute to this disparity. This article summarizes how functional neuroimaging works, focussing on functional MRI (FMRI) and magnetoencephalography, how neuroimaging has shed light on the central mechanisms of breathlessness and thus how it may help target new therapies. Current understanding of central neural activity in breathlessness comes mainly from a small number of studies in healthy volunteers using models of induced acute breathlessness. Parallels with neuroimaging findings in pain and fear or anxiety have been used to interpret the neuroimaging studies of breathlessness to form hypotheses. Despite the lack of recent neuroimaging studies in breathlessness, there have been methodological advances in overcoming confounders with respiratory FMRI. In addition, developing interest in the distinction of emotional from the sensory aspects of breathlessness and the use of opioids for breathlessness has driven mechanistic understandings. Neuroimaging of breathlessness remains in its infancy. However, advances in the understanding of central perception, combined with novel neuroimaging techniques, means that we are poised to increase our understanding of the brain processes of breathlessness and their modulation.

  5. Central core of the cerebrum.

    PubMed

    Choi, Chan-Young; Han, Seong-Rok; Yee, Gi-Taek; Lee, Chae-Heuck

    2011-02-01

    The purpose of this study was to understand 3D relationships of white matter fibers and subcortical areas of gray matter in the central core. The lateral and medial aspects of 4 cerebral hemispheres were dissected, applying the fiber dissection technique under the microscope. The central core between the insula and midline includes the extreme, external, and internal capsules; claustrum; putamen; globus pallidus; caudate nucleus; amygdala; diencephalon; substantia innominata; fornix; anterior commissure; mammillothalamic tract; fasciculus retroflexus; thalamic peduncles, including optic and auditory radiations; ansa peduncularis; thalamic fasciculus; and lenticular fasciculus. It is attached to the remainder of the cerebral hemisphere by the cerebral isthmus, which is composed of white matter fibers located between the dorsolateral margin of the caudate nucleus and the full circumference of the circular sulcus of insula. The rostral fibers of the corpus callosum are included in the frontal portion of the cerebral isthmus. It is very useful for neurosurgeons to facilitate the understanding of spatial relationships and pertinent surgical approaches in and around the central core with a highly complex anatomy by using fiber dissection.

  6. Evidence for central regulation of glucose metabolism.

    PubMed

    Carey, Michelle; Kehlenbrink, Sylvia; Hawkins, Meredith

    2013-12-06

    Evidence for central regulation of glucose homeostasis is accumulating from both animal and human studies. Central nutrient and hormone sensing in the hypothalamus appears to coordinate regulation of whole body metabolism. Central signals activate ATP-sensitive potassium (KATP) channels, thereby down-regulating glucose production, likely through vagal efferent signals. Recent human studies are consistent with this hypothesis. The contributions of direct and central inputs to metabolic regulation are likely of comparable magnitude, with somewhat delayed central effects and more rapid peripheral effects. Understanding central regulation of glucose metabolism could promote the development of novel therapeutic approaches for such metabolic conditions as diabetes mellitus.

  7. Central hypersensitivity in chronic musculoskeletal pain.

    PubMed

    Curatolo, Michele; Arendt-Nielsen, Lars

    2015-05-01

    Clinical research has consistently detected alteration in central pain processing leading to hypersensitivity. Most methods used in humans are reliable and have face validity to detect widespread central hypersensitivity. However, construct validity is difficult to investigate due to lack of gold standards. Reference values in the pain-free population have been generated, but need replication. Research on pain biomarkers that reflect specific central hypersensitivity processes is warranted. Few studies have analyzed the prognostic value of central hypersensitivity. Most medications acting at central level and some non-pharmacological approaches, including psychological interventions, are likely to attenuate central hypersensitivity.

  8. Central vascular catheter infections in a Hospital of Central Italy.

    PubMed

    Lombardi, Silvia; Scutell, Massimiliano; Felice, Valentina; Di Campli, Emanuela; Di Giulio, Mara; Cellini, Luigina

    2014-01-01

    The insertion and the permanence of central venous catheters (CVC) represent potential sources of infection contracted in hospital. The evaluation of the risk of CVC-associated infections was evaluated in a retrospective study during the period 2007-2010 in a Hospital of Central Italy. A total of 514 CVC were collected and examined by microbiological techniques and, among the examined patients, 450 CVC blood cultures were collected. Cultures were performed collecting a portion of 5-6 cm of intravenous catheters in liquid medium and spread on selective media for Gram-positive and Gram-negative bacteria and yeasts; blood specimens were obtained through peripheral venous punctures and analyzed by a commercial automated system. 308/514 (59.90%) samples were positive to the microbiological culture. Staphylococcus aureus, S. epidermidis and other coagulase negative Staphylococci (CNS) were the prevalent Gram-positive bacteria. Among Gram-negative bacteria, Enterobacteriaceae and Pseudomonaceae were the main bacteria isolated. A higher prevalence of Gram-positive bacteria was observed in Neonatal Pathology (90.90%). The Intensive Care Unit (ICU) showed 73.10% of positive cultures with 54.12% of Gram-positive isolates. Among positive blood cultures (38%), Gram-positive bacteria were the main bacteria isolated. The high prevalence of catheter-related infections requires accurate surveillance and the assumption of preventive measures in particular during catheter insertion.

  9. Training Educational Administrators in Central America

    ERIC Educational Resources Information Center

    Bernede, Jean-Francois

    1977-01-01

    Training of educational administrators in Central America is described and evaluated and future prospects are discussed. It is recommended that the six countries of Central America cooperate to achieve educational reform. (Author/DB)

  10. Central Saudi Arabia, Persian Gulf

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This panoramic view of Central Saudi Arabia and the Persian Gulf (28.0N, 47.0E) dramatically illustrates the stark beauty of the deserts. Riyadh, the capital city, lies in the foreground, with the Persian Gulf in the middle and Iran in the background. The coastal oil terminals of Al Hufuf and Ad Dammam are also visible. Black smudges of soot from the oil fires set during the Gulf War can be seen on the sands to the north and south of Kuwait City.

  11. Centralized Storm Information System (CSIS)

    NASA Technical Reports Server (NTRS)

    Norton, C. C.

    1985-01-01

    A final progress report is presented on the Centralized Storm Information System (CSIS). The primary purpose of the CSIS is to demonstrate and evaluate real time interactive computerized data collection, interpretation and display techniques as applied to severe weather forecasting. CSIS objectives pertaining to improved severe storm forecasting and warning systems are outlined. The positive impact that CSIS has had on the National Severe Storms Forecast Center (NSSFC) is discussed. The benefits of interactive processing systems on the forecasting ability of the NSSFC are described.

  12. The central arctic caribou herd

    USGS Publications Warehouse

    Cameron, Raymond D.; Smith, Walter T.; White, Robert G.; Griffith, Brad; Douglas, David C.; Reynolds, Patricia E.; Rhode, E.B.

    2002-01-01

    From the mid-1970s through the mid-1980s, use of calving and summer habitats by Central Arctic herd caribou (Rangifer tarandus granti) declined near petroleum development infrastructure on Alaska's arctic coastal plain (Cameron et al. 1979; Cameron and Whitten 1980, Smith and Cameron 1983. Whitten and Cameron 1983a, 1985: Dau and Cameron 1986).With surface development continuing to expand westward from the Prudhoe Bay petroleum development area (Fig. 4.1), concerns arose that the resultant cumulative losses of habitat would eventually reduce productivity of the caribou herd. Specifically, reduced access of adult females to preferred foraging areas might adversely affect growth and fattening (Elison et al. 1986. Clough et al. 1987), in turn depressing calf production (Dauphiné 1976, Thomas 1982, Reimers 1983, White 1983, Eloranta and Nieminen 1986. Lenvik et al. 1988, Thomas and Kiliaan 1991) and survival (Haukioja and Salovaara 1978, Rognmo et al. 1983, Skogland 1984, Eloranta and Nieminen 1986, Adamczewski et al. 1987).Those concerns, though justified in theory, lacked empirical support. With industrial development in arctic Alaska virtually unprecedented, there was little basis for predicting the extent and duration of habitat loss, much less the secondary short- and long-term effects on the well-being of a particular caribou herd.Furthermore, despite a general acceptance that body condition and fecundity of the females are functionally related for reindeer and caribou, it seemed unlikely that any single model would apply to all subspecies of Rangifer, and perhaps not even within a subspecies in different geographic regions. We therefore lacked a complete understanding of the behavioral responses of arctic caribou to industrial development, the manner in which access to habitats might be affected, and how changes in habitat use might translate into measurable effects on fecundity and herd growth rate.Our study addressed the following objectives: 1) estimate

  13. (Centralized Reliability Data Organization (CRDO))

    SciTech Connect

    Haire, M J

    1987-04-21

    One of the primary goals of the Centralized Reliability Data Organization (CREDO) is to be an international focal point for the collection, analysis, and dissemination of liquid metal reactor (LMR) component reliability, availability, and maintainability (RAM) data. During FY-1985, the Department of Energy (DOE) entered into a Specific Memorandum of Agreement (SMA) with Japan's Power Reactor and Nuclear Fuel Development Corporation (PNC) regarding cooperative data exchange efforts. This agreement was CREDO's first step toward internationalization and represented an initial realization of the previously mentioned goal. DOE's interest in further internationalization of the CREDO system was the primary motivation for the traveler's attendance at the Reliability '87 conference.

  14. Central and Southern Florida, USA

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This oblique view documents conditions in South Florida (27.0N, 81.0W) in the aftermath of Hurricane Andrew that severly mauled south Florida on 24 Aug 92, battering Dade County with a 16.9 ft. storm surge and wind gusts of up to 169 mph. An additional feature is the band of haze running across the central portion of the state The band of air pollution has been drawn from the north by a weak cold front and was focused along the east/west axis of the front.

  15. A Military Strategy for Central Asia

    DTIC Science & Technology

    2006-05-31

    Policy Toward Kazakhstan,” in Thinking Strategically : The Major Powers, Kazakhstan, and the Central Asian Nexus, ed. Robert Legvold (Cambridge, MA: MIT...Sherman W. “The Strategic Challenge of Kazakhstan and Inner Asia” In Thinking Strategically . The Major Powers, Kazakhstan, and the Central Asian Nexus, ed...Legvold, Robert, ed. “Great Power Stakes in Central Asia” In Thinking Strategically . The Major Powers, Kazakhstan, and the Central Asian Nexus, 1-38

  16. Distributed trace using central performance counter memory

    DOEpatents

    Satterfield, David L; Sexton, James C

    2013-10-22

    A plurality of processing cores, are central storage unit having at least memory connected in a daisy chain manner, forming a daisy chain ring layout on an integrated chip. At least one of the plurality of processing cores places trace data on the daisy chain connection for transmitting the trace data to the central storage unit, and the central storage unit detects the trace data and stores the trace data in the memory co-located in with the central storage unit.

  17. Distributed trace using central performance counter memory

    DOEpatents

    Satterfield, David L.; Sexton, James C.

    2013-01-22

    A plurality of processing cores, are central storage unit having at least memory connected in a daisy chain manner, forming a daisy chain ring layout on an integrated chip. At least one of the plurality of processing cores places trace data on the daisy chain connection for transmitting the trace data to the central storage unit, and the central storage unit detects the trace data and stores the trace data in the memory co-located in with the central storage unit.

  18. Government Venture Capital: Centralized or Decentralized Execution

    DTIC Science & Technology

    2007-12-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA MBA PROFESSIONAL REPORT Government Venture Capital: Centralized or...DATE December 2007 3. REPORT TYPE AND DATES COVERED MBA Professional Report 4. TITLE AND SUBTITLE Government Venture Capital: Centralized or...these questions is the following issue: Should the DoD manage VC in a centralized or decentralized manner? B. OBJECTIVES The purpose of this MBA

  19. 20 CFR 346.1 - Central register.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Central register. 346.1 Section 346.1... RAILROAD HIRING § 346.1 Central register. (a) The Board shall maintain a central register of railroad... employment. The register shall indicate which of those employees claims a first right of hire. (b)...

  20. 49 CFR 71.6 - Central zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Central zone. 71.6 Section 71.6 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.6 Central zone. The third zone, the central standard time zone, includes that part of the United States that is west of the...

  1. Central State University: Phase III Report

    ERIC Educational Resources Information Center

    Ohio Board of Regents, 2013

    2013-01-01

    This document is the final report on Central State University's implementation of Section 371 of Ohio Amended Substitute House Bill 153. Implementation of Phase I action items required that deliverables and timelines be shifted to give Central State the best opportunity for early success. In Phase II, Central State responded aggressively to a…

  2. 34 CFR 303.162 - Central directory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Central directory. 303.162 Section 303.162 Education... Central directory. Each application must include information and assurances demonstrating to the satisfaction of the Secretary that the State has developed a central directory of information that meets the...

  3. 20 CFR 346.1 - Central register.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Central register. 346.1 Section 346.1 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT RAILROAD HIRING § 346.1 Central register. (a) The Board shall maintain a central register of...

  4. Low clouds in central California

    NASA Image and Video Library

    2017-09-28

    Low clouds filled California’s Central Valley in late January, 2015. Such winter fog is considered a common phenomenon, and can be so dense that it snarls traffic, causes fender-benders, and can make symptoms worse in those with respiratory disease. At the same time, the moist winter fog helps keep temperatures low in the rich agricultural region by reflecting sunlight and keeping the ground from warming, which helps keep the abundant fruit and nut trees dormant, allowing for bountiful harvests. Scientific studies have reported that winter fogs (also called Thule fogs) are occurring less frequently in the Central Valley. One study, by Dennis Baldocchi and Eric Waller, was published in May, 2014. It finds that since 1981 the number of fog days between November and February has decreased by 46 percent. The severe drought that California has experienced in recent years may also have decreased the number of fog events even more since 2012. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image on January 24, 2015. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  5. Hazardous pesticides in Central America.

    PubMed

    Wesseling, C; Aragón, A; Castillo, L; Corriols, M; Chaverri, F; de la Cruz, E; Keifer, M; Monge, P; Partanen, T J; Ruepert, C; van Wendel de Joode, B

    2001-01-01

    Pesticides are an extensively documented occupational and environmental hazard in Central America. Yet, severe problems persist. Toxic pesticide use in the Region increased during 1985-1999. High exposure levels and ineffectiveness of personal protective equipment evidence the difficulties for risk reduction. Acute poisonings remain a severe problem. Delayed and/or long-lasting health effects include dermatoses, cancer, and genotoxic, neurotoxic, and respiratory effects. The use of hazardous pesticides persists through deficiencies in government-driven assessment and risk management; excessive focus on regional harmonization; short-term economic interests; strong links between industry and governments; aggressive marketing; weak trade unions; and failure of universities to reach decision makers. Regulation based on local data is lacking. An agreement of the Ministries of Health for restricting the most toxic pesticides in Central America has potential for progress. The most effective way to reduce risk is to greatly reduce pesticide use. Actions needed include development of multidisciplinary strategies for local studies on health and environmental impact of pesticides; development of sustainable nonchemical agricultural technologies; evaluation of interventions; extending and sharing of expertise within the Region; strengthening of unions and communities; and redefining the role of industry toward development of safer products, with responsible marketing and reliable information.

  6. [Central venous blood gas analysis].

    PubMed

    Marano, Marco; D'Amato, Anna; Guiotto, Giovanna; Schiraldi, Fernando

    2015-01-01

    The hemodialysis might interfere with patients hemodynamic, as the technique allows a sophisticated game with extra and intravascular fluids. As the cardiocirculatory response could sometimes be unpredictable, it is interesting to collect valuable information by reaching a deep understanding of the tissue metabolism which is mirrored by the blood gas analysis of variations in arterial and central venous blood samples. Particularly interesting are the time course variations of the central venous hemoglobin saturation (ScvO2), which are directly related to the patient with O2-demand as well as to the O2-Delivery (DO2). The ScvO2 is determined by four parameters (cardiac output, Hb concentration, arterial Hb saturation and O2 consumption): If the fluids subtraction during dialysis was about to determine an occult hypoperfusion, the ScvO2 reduction would be a timely warning sign to be considered. Moreover, while the normal veno-arterial PCO2 difference is 2-4 mmHg, whenever a mismatch between O2-demand and DO2arise, a larger v-aPCO2 difference should be observed.

  7. Primary hypersomnias of central origin.

    PubMed

    Frenette, Eric; Kushida, Clete A

    2009-09-01

    Hypersomnia is a frequently encountered symptom in clinical practice. The cardinal manifestation is inappropriate daytime sleepiness, common to all types of hypersomnias. Hypersomnias of central origin are a rare cause of excessive daytime sleepiness, much rarer than the hypersomnia related to other pathologies, such as sleep-disordered breathing. Narcolepsy, with or without cataplexy, remains the most well studied of the primary hypersomnias. Although recognized more than a century ago, it was not until the end of the 20th century that major breakthroughs led to a better understanding of the disease, with hope of more specific therapies. The authors review the major aspects of this disorder, including the newer treatment modalities. Idiopathic hypersomnia is also part of the primary hypersomnias. Although difficult to diagnose, certain peculiarities stand out to help us differentiate it from the more commonly seen narcolepsy. The recurrent hypersomnias, particularly the Kleine-Levin syndrome, will be discussed. This rare disorder has been studied more closely in the last few years with abundant epidemiologic data assembled through literature and worldwide case reviews. Understanding the primary central hypersomnias warrants a thorough look from the original description, as well as a peek at the future, while more efficacious diagnostic and therapeutic interventions are currently being developed.

  8. Precipitation chemistry in central Amazonia

    NASA Technical Reports Server (NTRS)

    Andreae, M. O.; Talbot, R. W.; Berresheim, H.; Beecher, K. M.

    1990-01-01

    Rain samples from three sites in central Amazonia were collected over a period of 6 weeks during the 1987 wet season and analyzed for ionic species and dissolved organic carbon. A continuous record of precipitation chemistry and amount was obtained at two of these sites, which were free from local or regional pollution, for a time period of over 1 month. The volume-weighted mean concentrations of most species were found to be about a factor of 5 lower during the wet season compared with previous results from the dry season. Only sodium, potassium, and chloride showed similar concentrations in both seasons. When the seasonal difference in rainfall amount is taken into consideration, the deposition fluxes are only slightly lower for most species during the wet season than during the dry season, again with the exception of chloride, potassium, and sodium. Sodium and chloride are present in the same ratio as in sea salt; rapid advection of air masses of marine origin to the central Amazon Basin during the wet season may be responsible for the observed higher deposition flux of these species. Statistical analysis suggests that sulfate is, to a large extent, of marine (sea salt and biogenic) origin, but that long-range transport of combustion-derived aerosols also makes a significant contribution to sulfate and nitrate levels in Amazonian rain. Organic acid concentrations in rain were responsible for a large fraction of the observed precipitation acidity; their concentration was strongly influenced by gas/liquid interactions.

  9. Central East Pacific Flight Routing

    NASA Technical Reports Server (NTRS)

    Grabbe, Shon; Sridhar, Banavar; Kopardekar, Parimal; Cheng, Nadia

    2006-01-01

    With the introduction of the Federal Aviation Administration s Advanced Technology and Oceanic Procedures system at the Oakland Oceanic Center, a level of automation now exists in the oceanic environment to potentially begin accommodating increased user preferred routing requests. This paper presents the results of an initial feasibility assessment which examines the potential benefits of transitioning from the fixed Central East Pacific routes to user preferred routes. As a surrogate for the actual user-provided routing requests, a minimum-travel-time, wind-optimal dynamic programming algorithm was developed and utilized in this paper. After first describing the characteristics (e.g., origin airport, destination airport, vertical distribution and temporal distribution) of the westbound flights utilizing the Central East Pacific routes on Dec. 14-16 and 19-20, the results of both a flight-plan-based simulation and a wind-optimal-based simulation are presented. Whereas the lateral and longitudinal distribution of the aircraft trajectories in these two simulations varied dramatically, the number of simulated first-loss-of-separation events remained relatively constant. One area of concern that was uncovered in this initial analysis was a potential workload issue associated with the redistribution of traffic in the oceanic sectors due to thc prevailing wind patterns.

  10. Central exclusive production at RHIC

    DOE PAGES

    Adamczyk, Leszek; Guryn, Włodek; Turnau, Jacek

    2014-11-10

    The present status and future plans of the physics program of Central Exclusive Production (CEP) at RHIC are described. The measurements are based on the detection of the forward protons from the Double Pomeron Exchange (DPE) process in the Roman Pot system and of the recoil system of charged particles from the DPE process measured in the STAR experiment’s Time Projection Chamber (TPC). The data described here were taken using polarized proton-proton collisions at ps = 200 GeV. The preliminary spectra of two pion and four pion invariant mass reconstructed by STAR TPC in central region of pseudo-rapidity | |more » < 1, are presented. Near future plans to take data with the current system at center-of-mass energy ps = 200 GeV and plans to upgrade the forward proton tagging sys- tem are presented. Also a possible addition of the Roman Pots to the sPHENIX detector is discussed.« less

  11. The phylogeny of central chemoreception.

    PubMed

    Milsom, W K

    2010-10-31

    Respiratory chemoreceptors responsive to changes in CO(2)/H(+) appear to be present in all vertebrates from fish to birds and mammals. They appear to have arisen first in the periphery sensitive to the external environment. Thus, in most fish CO(2)/H(+) chemoreceptors reside primarily in the gills and respond to changes in aquatic rather than arterial P(CO)₂ . In the air-breathing tetrapods (amphibians, mammals, reptiles and birds), the branchial arches regress developmentally and the derivatives of the branchial arteries are now exclusively internal. The receptors associated with these arteries now sense only arterial (not environmental) P(CO)₂/pH . Central CO(2)/H(+) chemoreception also appears to have arisen with the advent of air breathing, presumably as a second line of defense. These receptors may have arisen multiple times in association with several (but not all) of the independent origins of air breathing in fishes. There is strong evidence for multiple central sites of CO(2)/H(+) sensing, at least in amphibians and mammals, suggesting that it may not only have originated multiple times in different species but also multiple times within a single species.

  12. Occupational health in Central America.

    PubMed

    Wesseling, Catharina; Aragón, Aurora; Morgado, Hugo; Elgstrand, Kaj; Hogstedt, Christer; Partanen, Timo

    2002-01-01

    The 12.4 million economically active population (EAP) of the seven Central American countries includes a large informal sector. Social security covers only 14-60%. No surveillance of occupational safety and health (OSH) hazards or accidents exists. Extrapolating the incidence of occupational accidents among insured Costa Rican workers to the Central American EAP yields two million accidents yearly, still a gross underestimate. Occupational diseases are underreported, misdiagnosed, and not recognized as such. A number of regional OSH programs aim at modernization of the labor administrations and address the formal sector, in particular textile maquila, in connection with free trade agreements. The weak role of the ministries of health is expected to strengthen under the Pan American Health Organization OSH program. Employers largely influence new policies. Workers' influence on OSH policies has been weak, with only about 10% unionization rate and scarce resources and OSH knowledge. Informal workers, however, are getting organized. OSH research is underdeveloped and not linked to policy making. Construction, agriculture, and general un/underemployment are considered priorities for intervention. The informal sector needs to be included in national and regional OSH policies. Regional collaboration and international development support are of strategic importance to achieve sustainable improvement in OSH.

  13. Central vascular catheters and infections.

    PubMed

    Dioni, Elisabetta; Franceschini, Renata; Marzollo, Roberto; Oprandi, Daniela; Chirico, Gaetano

    2014-03-01

    Newborn infants in critical conditions require a permanent intra-venous line to allow for the administration of fluids, parenteral nutrition and drugs. The use of central venous catheters, however, is associated with an increased risk of infections, leading to prolongation of length of stay and higher hospitalization costs, particularly in extremely preterm infants. Dwell time is a significant factor for complications, with a predicted risk of catheter related infections of about 4 per 1000 catheter-days. To reduce the incidence of complications, several requirements must be met, including adequate staff and resources to provide education, training, and quality improvement programs, within a culture of communication and teamwork. Rigorous reporting schedule on line care and the implementation of unique bundle elements, the use of health care failure mode and effect analysis, the judicious use of antibiotics through an antimicrobial stewardship strategy, the application of specific antifungal prophylaxis are among the most effective interventions, while the addition of heparin to parenteral solution, or the use of antibiotic plus heparin lock therapy are under evaluation. Nursing assistance plays a fundamental role in managing central venous lines and in reducing or preventing the incidence of infection, by the application of several complex professional strategies.

  14. Exploration potential of Central Europe

    SciTech Connect

    Krueger, W.C. )

    1991-03-01

    Because of governmental changes an entire region of Central Europe has received exploration scrutiny not possible during the past 40-50 years. This entire area - Hungary, Czechoslovakia, Romania, Bulgaria, Yugoslavia, Albania, Poland, and East Germany - is tectonically related. Yugoslavia, although not under the same restrictions, is also considered in the same tectonic setting. Therefore, these countries can be expected to reflect some of the same stratigraphy, source rock, reservoir, trap and field types, and production history. Much of the region can be considered frontier while other parts mature. Production from all is about 55,000 T/D, 380,000 BO/D and 63.1 Bm{sup 3}/yr, 2,203 Bft{sup 3}/yr. Major source rocks have been identified as Tertiary-Oligocene, Miocene-Mesozoic, Triassic, Jurassic, and Cretaceous. Carboniferous coal sequences are considered source for the Permian. The East European platform and Tethyian plates are the foundation of the Central Europe states. Plate collisions during the late Mesozoic and into the Tertiary affected the Carpathian, Balkans, Dinarides, and Helenide Mountain chains. Mesozoic and Tertiary foredeep deposits have been proven productive from normal-, thrust-, and wrench-faulted anticlinal structures. Paleozoic, Mesozoic erosional remnants, and Tertiary lacustrine and deltaic stratigraphic deposits are the major productive reservoirs in the Pannonian basin. Permian shelf and reefal deposits are found in such areas as the Permian Shelf in Eastern Germany and Poland. Reefal plays may be found in Bulgaria and Romania offshore.

  15. Central Equatorial Pacific Experiment (CEPEX)

    SciTech Connect

    Not Available

    1993-01-01

    The Earth's climate has varied significantly in the past, yet climate records reveal that in the tropics, sea surface temperatures seem to have been remarkably stable, varying by less than a few degrees Celsius over geologic time. Today, the large warm pool of the western Pacific shows similar characteristics. Its surface temperature always exceeds 27[degree]C, but never 31[degree]C. Heightened interest in this observation has been stimulated by questions of global climate change and the exploration of stabilizing climate feedback processes. Efforts to understand the observed weak sensitivity of tropical sea surface temperatures to climate forcing has led to a number of competing ideas about the nature of this apparent thermostat. Although there remains disagreement on the processes that regulate tropical sea surface temperature, most agree that further progress in resolving these differences requires comprehensive field observations of three-dimensional water vapor concentrations, solar and infrared radiative fluxes, surface fluxes of heat and water vapor, and cloud microphysical properties. This document describes the Central Equatorial Pacific Experiment (CEPEX) plan to collect such observations over the central equatorial Pacific Ocean during March of 1993.

  16. Central Solenoid Insert Technical Specification

    SciTech Connect

    Martovetsky, Nicolai N; Smirnov, Alexandre

    2011-09-01

    The US ITER Project Office (USIPO) is responsible for the ITER central solenoid (CS) contribution to the ITER project. The Central Solenoid Insert (CSI) project will allow ITER validation the appropriate lengths of the conductors to be used in the full-scale CS coils under relevant conditions. The ITER Program plans to build and test a CSI to verify the performance of the CS conductor. The CSI is a one-layer solenoid with an inner diameter of 1.48 m and a height of 4.45 m between electric terminal ends. The coil weight with the terminals is approximately 820 kg without insulation. The major goal of the CSI is to measure the temperature margin of the CS under the ITER direct current (DC) operating conditions, including determining sensitivity to load cycles. Performance of the joints, ramp rate sensitivity, and stability against thermal or electromagnetic disturbances, electrical insulation, losses, and instrumentation are addressed separately and therefore are not major goals in this project. However, losses and joint performance will be tested during the CSI testing campaign. The USIPO will build the CSI that will be tested at the Central Solenoid Model Coil (CSMC) Test Facility at the Japan Atomic Energy Agency (JAEA), Naka, Japan. The industrial vendors (the Suppliers) will report to the USIPO (the Company). All approvals to proceed will be issued by the Company, which in some cases, as specified in this document, will also require the approval of the ITER Organization. Responsibilities and obligations will be covered by respective contracts between the USIPO, called Company interchangeably, and the industrial Prime Contractors, called Suppliers. Different stages of work may be performed by more than one Prime Contractor, as described in this specification. Technical requirements of the contract between the Company and the Prime Contractor will be covered by the Fabrication Specifications developed by the Prime Contractor based on this document and approved by

  17. Anatomical basis of central venous catheter fracture.

    PubMed

    Jensen, Mark O

    2008-03-01

    Central venous catheter fracture is a rare complication of long-term indwelling subclavian venous access. Subclavian vein access has been the recommended approach for placing central venous catheters. The anatomical landmark method for subclavian access remains a highly successful and nonequipment-dependent method for rapid central access. More recently, the internal jugular vein approach has emerged as the preferred route for long-term central venous access. However, variations in internal jugular vein anatomy make the landmark method less reliable. Use of two-dimensional real-time ultrasound during internal jugular vein access is associated with better success, a lower complication rate, and faster access. A case of central venous catheter fracture initiated an internal review of long-term central venous access procedures. We have converted to a predominantly internal jugular vein approach. This case report and literature review may assist other physicians and institutions in re-evaluating long-term central venous access protocols.

  18. Geology of central Lake Michigan.

    USGS Publications Warehouse

    Wood, R.J.; Paull, R.A.; Wolosin, C.A.; Friedel, R.J.

    1981-01-01

    The geology beneath central Lake Michigan is interpreted from a synthesis of 1,700 km of continuous seismic reflection profile data, bathymetry, grab samples, and onshore surface and subsurface information. The map of unconsolidated sediment (primarily Pleistocene) shows thicknesses ranging from 180 m in a steep- walled, northeast-trending valley to less than 10 m over a mid-lake topographic high. These are the dominant features developed on the gently eastward-dipping Paleozoic rocks along this part of the western flank of the Michigan basin. Two structural-stratigraphic cross sections of the study area were constructed. The cross sections, grab samples and other information were used to construct a Paleozoic geologic map. Speculations are made about the petroleum potential beneath Lake Michigan. -from Authors

  19. Central solar-energy receiver

    DOEpatents

    Not Available

    1981-10-27

    An improved tower-mounted central solar energy receiver for heating air drawn through the receiver by an induced draft fan is described. A number of vertically oriented, energy absorbing, fin-shaped slats are radially arranged in a number of concentric cylindrical arrays on top of the tower coaxially surrounding a pipe having air holes through which the fan draws air which is heated by the slats which receive the solar radiation from a heliostat field. A number of vertically oriented and wedge-shaped columns are radially arranged in a number of concentric cylindrical clusters surrounding the slat arrays. The columns have two mirror-reflecting sides to reflect radiation into the slat arrays and one energy absorbing side to reduce reradiation and reflection from the slat arrays.

  20. [Suppurative thrombophlebitis central venous catheterization].

    PubMed

    Ramos Martínez, A; Sánchez Romero, I; Saura Lorente, P A; Parajón Díaz, A

    2008-06-01

    Suppurative thrombophlebitisis a very infrequent complication of the central venous catheterization. The majority of the cases are produced by species of staphylococci. A 22-year-old colombian-woman, student, without toxic habits was admitted because of temporary left astrocytoma (grade II). Nine days after implementing a catheter in the right subclavian vein she presented high fever (39.5 degrees C), shivers, progressive right side neck swelling and odinofagia. She had leukocytosis (26,300 cells/microl) and normal cerebrospinal fluid. After withdrawing the catheter, Staphylococcus aureus was isolated in the tip of the catheter and in four bottles of blood cultures. A neck CT demonstrated expansion and absence of contrast in the right internal jugular vein. The patient evolved satisfactorily with cloxacillin, gentamycin and low molecular weight heparin.

  1. Peripherally Inserted Central Catheters and Hemodialysis Outcomes.

    PubMed

    McGill, Rita L; Ruthazer, Robin; Meyer, Klemens B; Miskulin, Dana C; Weiner, Daniel E

    2016-08-08

    Use of peripherally inserted central catheters has expanded rapidly, but the consequences for patients who eventually require hemodialysis are undefined. Our national, population-based analysis included 33,918 adult Medicare beneficiaries from the US Renal Data System who initiated hemodialysis with central venous catheters as their sole vascular access in 2010 and 2011. We used linked Medicare claims to identify peripherally inserted central catheter exposures and evaluate the associations of peripherally inserted central catheter placement with transition to working arteriovenous fistulas or grafts and patient survival using a Cox model with time-dependent variables. Among 33,918 individuals initiating hemodialysis with a catheter as sole access, 12.6% had received at least one peripherally inserted central catheter. Median follow-up was 404 days (interquartile range, 103-680 days). Among 6487 peripherally inserted central catheters placed, 3435 (53%) were placed within the 2 years before hemodialysis initiation, and 3052 (47%) were placed afterward. Multiple peripherally inserted central catheters were placed in 30% of patients exposed to peripherally inserted central catheters. Recipients of peripherally inserted central catheters were more likely to be women and have comorbid diagnoses and less likely to have received predialysis nephrology care. After adjustment for clinical and demographic factors, peripherally inserted central catheters placed before or after hemodialysis initiation were independently associated with lower likelihoods of transition to any working fistula or graft (hazard ratio for prehemodialysis peripherally inserted central catheter, 0.85; 95% confidence interval, 0.79 to 0.91; hazard ratio for posthemodialysis peripherally inserted central catheter, 0.81; 95% confidence interval, 0.73 to 0.89). Peripherally inserted central catheter placement was common and associated with adverse vascular access outcomes. Recognition of potential long

  2. Unsettled weather across central Australia

    NASA Image and Video Library

    2017-09-27

    In late July 2013, a low pressure system off Australia’s southeast coast and moist onshore winds combined to create unsettled weather across central Australia – and a striking image of a broad cloud band across the stark winter landscape. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image on July 22 at 01:05 UTC (10:35 a.m. Australian Central Standard Time). To the west of the low pressure trough the skies are clear and dry. To the east, the broad band of bright white clouds obscures the landscape. The system brought wind, precipitation and cooler temperatures to the region. The same day as MODIS captured this image, the Naval Research Lab (NRL) published an edition of the Global Storm Tracker (GST), which gave a world-wide view of the low-pressure systems across the world. This tracker shows the entire cloud band across Australia, as well as the location of the low pressure system. A good view of the Storm Tracker is provided by Red Orbit at: www.redorbit.com/media/uploads/2013/07/072213-weather-003... Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  3. Wooden Calendars from Central Rhodopes

    NASA Astrophysics Data System (ADS)

    Koleva, V.

    2008-10-01

    Four wooden calendars from the village of Polkovnik Serafimovo, Smolyan region, in the Central Rhodopes are presented here, and three of them - for the first time. The shape and size, the kind of the signs and structure of the calendar record bear the characteristic features of the rest of the Bulgarian wooden calendars. The short notches on the edges represent the days of the year in the Julian (solar) calendar. The special signs on the sides mark the fixed festivals of the Orthodox Church calendar and are also influenced by the local tradition. The type of the signs confirms that the wooden sticks belong to the group of calendars from the Central Rhodopes. According to the beginning date of the calendar record on the sticks, two of the calendars are of the April (May) or October (November) type which corresponds to the very popular economic division of the year in the folk calendar into two periods -- warm and cold. The other two sticks, which are very similar to each other, make an exception in this respect among the rest of the Bulgarian wooden calendars. The months are divided into four groups (seasons) on each of the four edges of the stick (only one calendar from Burgas region has the same structure). The most interesting thing about the two sticks is that this is the only case among all known Bulgarian calendars that the beginning of the calendar record coincides with the beginning of the civil year on 1st January (January type) like some wooden calendars from Western Europe. Nowadays it is getting harder and harder to find wooden calendars in Bulgaria and in the neighbouring Balkan countries. The thorough knowledge about them could be helpful in various scientific fields, e.g. history of religion, ethnology, history of astronomy and mathematics, as well as semiotics.

  4. Oil and gas developments in South America, Central America, Caribbean area, and Mexico in 1983

    SciTech Connect

    Tappmeyer, D.M.

    1984-10-01

    Petroleum exploration in the region was generally less in 1983 than in 1982. Brazil, Colombia, Ecuador, and Barbados increased crude production, whereas Argentina, Bolivia, Brazil, Colombia, Ecuador, Mexico, and Trinidad-Tobago reported increases in gas production. Although drilling activities remained low compared to past years, significant oil discoveries were reported in Colombia, Mexico, and Brazil. In Colombia, Cano Limon field is reported to be the largest field found in the Llanos region. In Brazil, important oil discoveries were made offshore in the Para, Potiquas, and Ampos basins. In Mexico, discoveries were reported in the Cerro Azul, Poza Rica (Chicontepec, Villahermosa, and Tabasco) areas onshore and in the Bay of Campeche offshore. In Argentina, discoveries were made in the San Jorge basin and the Noreste Tarija basin. 10 figures, 11 tables.

  5. Approximating centrality in evolving graphs: toward sublinearity

    NASA Astrophysics Data System (ADS)

    Priest, Benjamin W.; Cybenko, George

    2017-05-01

    The identification of important nodes is a ubiquitous problem in the analysis of social networks. Centrality indices (such as degree centrality, closeness centrality, betweenness centrality, PageRank, and others) are used across many domains to accomplish this task. However, the computation of such indices is expensive on large graphs. Moreover, evolving graphs are becoming increasingly important in many applications. It is therefore desirable to develop on-line algorithms that can approximate centrality measures using memory sublinear in the size of the graph. We discuss the challenges facing the semi-streaming computation of many centrality indices. In particular, we apply recent advances in the streaming and sketching literature to provide a preliminary streaming approximation algorithm for degree centrality utilizing CountSketch and a multi-pass semi-streaming approximation algorithm for closeness centrality leveraging a spanner obtained through iteratively sketching the vertex-edge adjacency matrix. We also discuss possible ways forward for approximating betweenness centrality, as well as spectral measures of centrality. We provide a preliminary result using sketched low-rank approximations to approximate the output of the HITS algorithm.

  6. Central Gain Control in Tinnitus and Hyperacusis

    PubMed Central

    Auerbach, Benjamin D.; Rodrigues, Paulo V.; Salvi, Richard J.

    2014-01-01

    Sensorineural hearing loss induced by noise or ototoxic drug exposure reduces the neural activity transmitted from the cochlea to the central auditory system. Despite a reduced cochlear output, neural activity from more central auditory structures is paradoxically enhanced at suprathreshold intensities. This compensatory increase in the central auditory activity in response to the loss of sensory input is referred to as central gain enhancement. Enhanced central gain is hypothesized to be a potential mechanism that gives rise to hyperacusis and tinnitus, two debilitating auditory perceptual disorders that afflict millions of individuals. This review will examine the evidence for gain enhancement in the central auditory system in response to cochlear damage. Further, it will address the potential cellular and molecular mechanisms underlying this enhancement and discuss the contribution of central gain enhancement to tinnitus and hyperacusis. Current evidence suggests that multiple mechanisms with distinct temporal and spectral profiles are likely to contribute to central gain enhancement. Dissecting the contributions of these different mechanisms at different levels of the central auditory system is essential for elucidating the role of central gain enhancement in tinnitus and hyperacusis and, most importantly, the development of novel treatments for these disorders. PMID:25386157

  7. Anisotropy Studies in Central Greece

    NASA Astrophysics Data System (ADS)

    Kaviris, G.; Papadimitriou, P.; Makropoulos, K.

    2007-12-01

    The Gulf of Corinth, located in Central Greece, is a tectonic graben characterized by high seismicity level. GPS measurements indicate extension of the Gulf in an approximately N-S direction, with a rate of 10 to 15 mm/year. The southern part of the Gulf is dominated by the presence of large active normal faults in an almost E-W direction, dipping north, resulting to the subsidence of the central part of the graben. Analysis of data recorded by the Cornet network, which is the permanent network of the University of Athens, revealed the existence of an anisotropic upper crust at the eastern part of the Gulf of Corinth. Anisotropy was also observed at the western part of Corinth Gulf, using data recorded by a temporary seismological network installed in the area. Furthermore, shear wave splitting analysis was performed in the region of Attica (to the NE of the Gulf) that hosts Athens, the capital of Greece, using aftershocks of the 1999 Athens earthquake (Mw=6.0) that caused 143 fatalities. The methods used for the determination of the splitting parameters are the polarization vector as a function of time (polarigram) and the hodogram. For each selected event the direction of polarization of the fast shear wave, the delay between the two split shear waves and the polarization of the source were measured. Concerning both parts of the Gulf of Corinth, the obtained mean values of anisotropy vary between N90° and N142°. In the region of Attica the mean values of the anisotropy direction of all stations vary between N95° and N100°, almost parallel to the azimuth of the Parnitha fault. The time delay between the split shear waves vary between 0.020s and 0.130s. The obtained anisotropy measurements are in agreement with the extensive dilatancy anisotropy (EDA) model, since the direction of anisotropy is independent from the event-station azimuth and perpendicular to the direction of extension. ACKNOWLEDGMENTS The present study was co-funded by the European Social Fund

  8. ITER Central Solenoid Module Fabrication

    SciTech Connect

    Smith, John

    2016-09-23

    The fabrication of the modules for the ITER Central Solenoid (CS) has started in a dedicated production facility located in Poway, California, USA. The necessary tools have been designed, built, installed, and tested in the facility to enable the start of production. The current schedule has first module fabrication completed in 2017, followed by testing and subsequent shipment to ITER. The Central Solenoid is a key component of the ITER tokamak providing the inductive voltage to initiate and sustain the plasma current and to position and shape the plasma. The design of the CS has been a collaborative effort between the US ITER Project Office (US ITER), the international ITER Organization (IO) and General Atomics (GA). GA’s responsibility includes: completing the fabrication design, developing and qualifying the fabrication processes and tools, and then completing the fabrication of the seven 110 tonne CS modules. The modules will be shipped separately to the ITER site, and then stacked and aligned in the Assembly Hall prior to insertion in the core of the ITER tokamak. A dedicated facility in Poway, California, USA has been established by GA to complete the fabrication of the seven modules. Infrastructure improvements included thick reinforced concrete floors, a diesel generator for backup power, along with, cranes for moving the tooling within the facility. The fabrication process for a single module requires approximately 22 months followed by five months of testing, which includes preliminary electrical testing followed by high current (48.5 kA) tests at 4.7K. The production of the seven modules is completed in a parallel fashion through ten process stations. The process stations have been designed and built with most stations having completed testing and qualification for carrying out the required fabrication processes. The final qualification step for each process station is achieved by the successful production of a prototype coil. Fabrication of the first

  9. Central Diabetes Insipidus presenting with manic symptoms.

    PubMed

    Sachdeva, Jasmine Kaur; Chalana, Harsh

    2011-09-01

    Central Diabetes Insipidus mostly presents with polydipsia and polyuria but may also present with confusion, psychosis, seizure or coma. We present a case of Central Diabetes Insipidus presenting with manic symptoms. A 21 year old Indian male had Central Diabetes Insipidus, which was confirmed by water deprivation test. He presented to our hospital with full blown manic symptoms meeting the ICD 10 criteria. He was managed with intranasal Desmopressin, water restriction and Olanzapine. In contrary to routine psychiatric patients which may present with psychogenic polydipsia or Central Diabetes Insipidus patients presenting in delirium or psychosis, our case presents a unique example of Central Diabetes Insipidus presenting with manic symptoms. It hints about a relationship between a common pathway for Central Diabetes Insipidus and mood disorders which needs further research. Diencephalon has already been the focus of attention for several researchers but no concrete evidence is available yet. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Properties of the Central American cold surge

    NASA Technical Reports Server (NTRS)

    Mcguirk, James P.; Reding, Philip J.; Zhang, Yuxia

    1993-01-01

    The Central American cold surge (CACS) is a frontal incursion from the United States into Central America and resembles the East Asian cold surge. They occur more frequently than analyzed by NMC or by published results, based on our observations between 1979 and 1990. Climatology and structure are quantified, based on surface and upper air stations throughout Central America and satellite products from GOES visible and infrared sensors and SSM/I precipitable water and rain rate sensors.

  11. The economics of central billing offices.

    PubMed

    Woodcock, E; Nguyen, L

    2000-01-01

    The anticipation of economies of scale in physician billing has led many medical practices to consolidate their billing operations. This article analyzes these economies of scale, comparing performance indicators from centralized and decentralized operations. While consolidation provides compliance, control and information, diseconomies of scale can exist in the centralized receivables management process. The authors conclude that physician practices should consider a hybrid approach to billing, thus reaping the benefits of both centralization and decentralization.

  12. A central theory of biology.

    PubMed

    Torday, John S

    2015-07-01

    The history of physiologic cellular-molecular interrelationships can be traced all the way back to the unicellular state by following the pathway formed by lipids ubiquitously accommodating calcium homeostasis, and its consequent adaptive effects on oxygen uptake by cells, tissues and organs. As a result, a cohesive, mechanistically integrated view of physiology can be formulated by recognizing the continuum comprising conception, development, physiologic homeostasis and death mediated by soluble growth factor signaling. Seeing such seemingly disparate processes as embryogenesis, chronic disease and dying as the gain and subsequent loss of cell-cell signaling provides a novel perspective for physiology and medicine. It is emblematic of the self-organizing, self-referential nature of life, starting from its origins. Such organizing principles obviate the pitfalls of teleologic evolution, conversely providing a way of resolving such seeming dichotomies as holism and reductionism, genotype and phenotype, emergence and contingence, proximate and ultimate causation in evolution, cells and organisms. The proposed approach is scale-free and predictive, offering a Central Theory of Biology.

  13. Conductivity Anomalies in Central Europe

    NASA Astrophysics Data System (ADS)

    Neska, Anne

    2016-01-01

    This paper is a review of studies which, by applying the magnetotelluric, geomagnetic deep sounding, and magnetovariational sounding methods (the latter refers to usage of the horizontal magnetic tensor), investigate Central Europe for zones of enhanced electrical conductivity. The study areas comprise the region of the Trans-European Suture Zone (i.e. the south Baltic region and Poland), the North German Basin, the German and Czech Variscides, the Pannonian Basin (Hungary), and the Polish, Slovakian, Ukrainian, and Romanian Carpathians. This part of the world is well investigated in terms of data coverage and of the density of published studies, whereas the certainty that the results lead to comprehensive interpretations varies within the reviewed literature. A comparison of spatially coincident or adjacent studies reveals the important role that the data coverage of a distinct conductivity anomaly plays for the consistency of results. The encountered conductivity anomalies are understood as linked to basin sediments, asthenospheric upwelling, large differences in lithospheric age, and—this concerns most of them, which all concentrate in the middle crust—tectonic boundaries that developed during all mountain building phases that have taken place on the continent.

  14. [Aniseikonia of central serous chorioretinopathy].

    PubMed

    Hisada, H; Awaya, S

    1992-03-01

    Central serous chorioretinopathy (CRS) is one of the typical diseases that accompany micropsia. However very little is known about micropsia of CRS, because of the difficulty to measure "aniseikonia" in terms of micropsia. Aniseikonia in 65 cases of CRS was measured quantitatively by Awaya's New Aniseikonia Tests (NAT). The tests were performed at two different distances of 40 cm (visual angle: 6 degrees) and 20 cm (12 degrees) and under 4 meridians of the halfmoon on NAT, horizontal, 45 degrees, vertical and 135 degrees, respectively. The mean value of aniseikonia under each testing condition was as follows: 6 degrees horizontal -3.13%, 45 degrees -2.56%, vertical -2.13%, 135 degrees -2.57%, 12 degrees; horizontal -1.38%, 45 degrees -1.69%, vertical -1.84%, 135 degrees -1.50%. At 6 degrees aniseikonia is larger in the horizontal meridian than in the vertical with statistical significance (t-test, p less than 0.05), while at 12 degrees aniseikonia is smaller than at 6 degrees and shows no particular tendency in terms of meridian. The phenomenon observed at 6 degrees may be what is called "oriented metamorphopsia".

  15. A Central Theory of Biology

    PubMed Central

    Torday, John S.

    2015-01-01

    The history of physiologic cellular–molecular interrelationships can be traced all the way back to the unicellular state by following the pathway formed by lipids ubiquitously accommodating calcium homeostasis, and its consequent adaptive effects on oxygen uptake by cells, tissues and organs. As a result, a cohesive, mechanistically integrated view of physiology can be formulated by recognizing the continuum comprising conception, development, physiologic homeostasis and death mediated by soluble growth factor signaling. Seeing such seemingly disparate processes as embryogenesis, chronic disease and dying as the gain and subsequent loss of cell–cell signaling provides a novel perspective for physiology and medicine. It is emblematic of the self-organizing, self-referential nature of life, starting from its origins. Such organizing principles obviate the pitfalls of teleologic evolution, conversely providing a way of resolving such seeming dichotomies as holism and reductionism, genotype and phenotype, emergence and contingence, proximate and ultimate causation in evolution, cells and organisms. The proposed approach is scale-free and predictive, offering a Central Theory of Biology. PMID:25911556

  16. Geology of central Lake Michigan

    SciTech Connect

    Wold, R.J.; Paull, R.A.; Wolosin, C.A.; Friedel, R.J.

    1981-09-01

    The geology beneath Lake Michigan between 43/sup 0/00' and 44/sup 0/00'N and between 86/sup 0/30' and 87/sup 0/40' W is interpreted from a synthesis of 1,700 km of continuous seismic reflection profile data, bathymetry, grab samples, and onshore surface and subsurface information. The continuous seismic reflection profiles and bathymetry provided information for maps of unconsolidated sediment thickness and Paleozoic bedrock topography. Two structural-stratigraphic cross sections of the study area were constructed by utilizing a composite subsurface-surface section for eastern Wisconsin and two control wells in western Michigan. The cross sections, grab samples previously described in the literature, the bedrock topographic map, and published maps were used to construct a Paleozoic geologic map for central Lake Michigan. Rocks from Middle Silurian through Early Mississippian age form subcrops beneath the study area, whereas rocks of Early Silurian, Ordovician, and Late Cambrian age are present at greater depth. The Upper Cambrian rocks unconformably overlie Precambrian igneous and metamorphic rocks. The structural-stratigraphic cross sections also allow speculation about the petroleum potential beneath Lake Michigan. The possibility of oil occurrences within the Silurian is enhanced by major east-west facies changes, and other horizons with promise are present in Devonian and Ordovician rocks. Although Michigan and Wisconsin laws currently prohibit petroleum exploration in Lake Michigan, it is an area with future potential.

  17. Central neural pathways for thermoregulation

    PubMed Central

    Morrison, Shaun F.; Nakamura, Kazuhiro

    2010-01-01

    Central neural circuits orchestrate a homeostatic repertoire to maintain body temperature during environmental temperature challenges and to alter body temperature during the inflammatory response. This review summarizes the functional organization of the neural pathways through which cutaneous thermal receptors alter thermoregulatory effectors: the cutaneous circulation for heat loss, the brown adipose tissue, skeletal muscle and heart for thermogenesis and species-dependent mechanisms (sweating, panting and saliva spreading) for evaporative heat loss. These effectors are regulated by parallel but distinct, effector-specific neural pathways that share a common peripheral thermal sensory input. The thermal afferent circuits include cutaneous thermal receptors, spinal dorsal horn neurons and lateral parabrachial nucleus neurons projecting to the preoptic area to influence warm-sensitive, inhibitory output neurons which control thermogenesis-promoting neurons in the dorsomedial hypothalamus that project to premotor neurons in the rostral ventromedial medulla, including the raphe pallidus, that descend to provide the excitation necessary to drive thermogenic thermal effectors. A distinct population of warm-sensitive preoptic neurons controls heat loss through an inhibitory input to raphe pallidus neurons controlling cutaneous vasoconstriction. PMID:21196160

  18. Maximal switchability of centralized networks

    NASA Astrophysics Data System (ADS)

    Vakulenko, Sergei; Morozov, Ivan; Radulescu, Ovidiu

    2016-08-01

    We consider continuous time Hopfield-like recurrent networks as dynamical models for gene regulation and neural networks. We are interested in networks that contain n high-degree nodes preferably connected to a large number of N s weakly connected satellites, a property that we call n/N s -centrality. If the hub dynamics is slow, we obtain that the large time network dynamics is completely defined by the hub dynamics. Moreover, such networks are maximally flexible and switchable, in the sense that they can switch from a globally attractive rest state to any structurally stable dynamics when the response time of a special controller hub is changed. In particular, we show that a decrease of the controller hub response time can lead to a sharp variation in the network attractor structure: we can obtain a set of new local attractors, whose number can increase exponentially with N, the total number of nodes of the nework. These new attractors can be periodic or even chaotic. We provide an algorithm, which allows us to design networks with the desired switching properties, or to learn them from time series, by adjusting the interactions between hubs and satellites. Such switchable networks could be used as models for context dependent adaptation in functional genetics or as models for cognitive functions in neuroscience.

  19. Towards a centralized Grid Speedometer

    NASA Astrophysics Data System (ADS)

    Dzhunov, I.; Andreeva, J.; Fajardo, E.; Gutsche, O.; Luyckx, S.; Saiz, P.

    2014-06-01

    Given the distributed nature of the Worldwide LHC Computing Grid and the way CPU resources are pledged and shared around the globe, Virtual Organizations (VOs) face the challenge of monitoring the use of these resources. For CMS and the operation of centralized workflows, the monitoring of how many production jobs are running and pending in the Glidein WMS production pools is very important. The Dashboard Site Status Board (SSB) provides a very flexible framework to collect, aggregate and visualize data. The CMS production monitoring team uses the SSB to define the metrics that have to be monitored and the alarms that have to be raised. During the integration of CMS production monitoring into the SSB, several enhancements to the core functionality of the SSB were required; They were implemented in a generic way, so that other VOs using the SSB can exploit them. Alongside these enhancements, there were a number of changes to the core of the SSB framework. This paper presents the details of the implementation and the advantages for current and future usage of the new features in SSB.

  20. Primary central nervous system lymphoma.

    PubMed

    Pels, Hendrik; Schlegel, Uwe

    2006-07-01

    There is no class I evidence for any therapeutic option in primary central nervous system lymphoma (PCNSL). When possible, patients should be included in clinical trials. The role of surgery is restricted to stereotactic biopsy in order to gain material for histopathologic diagnosis. Radiotherapy alone is associated with a median survival of no more than 1.5 years; cure is exceptional. However, in patients aged younger than 60 years, cure is the therapeutic aim. Polychemotherapy based on high-dose methotrexate with deferred radiation results in long-term survival in most of these patients and possibly cure in a substantial fraction of these patients. With regard to chemotherapy in PCNSL, the following must be considered: 1) the most efficient drug in PCNSL is methotrexate at a dosage of at least 1.5 g/m(2) per single dose; 2) methotrexate alone will lead to complete remission in only some patients, whereas the combination of methotrexate with other drugs is more efficient; and 3) the value of additional intraventricular chemotherapy and the necessity of "consolidation" radiotherapy after response to chemotherapy are not yet defined. For patients aged older than 60 years, no curative regimen with acceptable toxicity has yet been established. The combination of radiotherapy with methotrexate-based chemotherapy leads to severe long-term neurotoxic sequelae, ie, cognitive dysfunction, in most older patients and in some patients aged younger than 60 years.

  1. Towards a centralized Grid Speedometer

    SciTech Connect

    Dzhunov, I.; Andreeva, J.; Fajardo, E.; Gutsche, O.; Luyckx, S.; Saiz, P.

    2014-01-01

    Given the distributed nature of the Worldwide LHC Computing Grid and the way CPU resources are pledged and shared around the globe, Virtual Organizations (VOs) face the challenge of monitoring the use of these resources. For CMS and the operation of centralized workflows, the monitoring of how many production jobs are running and pending in the Glidein WMS production pools is very important. The Dashboard Site Status Board (SSB) provides a very flexible framework to collect, aggregate and visualize data. The CMS production monitoring team uses the SSB to define the metrics that have to be monitored and the alarms that have to be raised. During the integration of CMS production monitoring into the SSB, several enhancements to the core functionality of the SSB were required, They were implemented in a generic way, so that other VOs using the SSB can exploit them. Alongside these enhancements, there were a number of changes to the core of the SSB framework. This paper presents the details of the implementation and the advantages for current and future usage of the new features in SSB.

  2. Central-Monitor Software Module

    NASA Technical Reports Server (NTRS)

    Bachelder, Aaron; Foster, Conrad

    2005-01-01

    One of the software modules of the emergency-vehicle traffic-light-preemption system of the two preceding articles performs numerous functions for the central monitoring subsystem. This module monitors the states of all units (vehicle transponders and intersection controllers): It provides real-time access to the phases of traffic and pedestrian lights, and maps the positions and states of all emergency vehicles. Most of this module is used for installation and configuration of units as they are added to the system. The module logs all activity in the system, thereby providing information that can be analyzed to minimize response times and optimize response strategies. The module can be used from any location within communication range of the system; with proper configuration, it can also be used via the Internet. It can be integrated into call-response centers, where it can be used for alerting emergency vehicles and managing their responses to specific incidents. A variety of utility subprograms provide access to any or all units for purposes of monitoring, testing, and modification. Included are "sniffer" utility subprograms that monitor incoming and outgoing data for accuracy and timeliness, and that quickly and autonomously shut off malfunctioning vehicle or intersection units.

  3. Children in Central America: Victims of War.

    ERIC Educational Resources Information Center

    Ronstrom, Anitha

    1989-01-01

    Discusses the armed conflicts in Central America and their influence on civilian populations. Discusses the psychosocial consequences and therapeutic considerations of warfare, displacement and refuge for children. (RJC)

  4. Central poststroke pain: A systematic review.

    PubMed

    Singer, Jonathan; Conigliaro, Alyssa; Spina, Elizabeth; Law, Susan W; Levine, Steven R

    2017-06-01

    Background Physical, psychological, and/or social impairment can result after a stroke and can be exacerbated by pain. One type of pain after stroke, central poststroke pain, is believed to be due to primary central nervous system mechanisms. Estimated prevalence of central poststroke pain ranges widely from 8% to 55% of stroke patients, suggesting a difficulty in reliably, accurately, and consistently identifying central poststroke pain. This may be due to the absence of a generally accepted definition. Aim We aimed to clarify the role of thalamic strokes and damage to the spinothalamic pathway in central poststroke pain patients. Also, we aimed to gain a current understanding of anatomic substrates, brain imaging, and treatment of central poststroke pain. Summary of review Two independent reviewers identified 10,144 publications. Based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, we extracted data from 23 papers and categorized the articles' aims into four sections: somatosensory deficits, pathway stimulation, clinical trials, and brain imaging. Conclusions Our systematic review suggests that damage to the spinothalamic pathway is associated with central poststroke pain and this link could provide insights into mechanisms and treatment. Moreover, historical connection of strokes in the thalamic region of the brain and central poststroke pain should be reevaluated as many studies noted that strokes in other regions of the brain have high occurrence of central poststroke pain as well.

  5. Central cell confinement in MFTF-B

    SciTech Connect

    Jong, R.A.

    1981-05-05

    The point code TANDEM has been used to survey the range of plasma parameters which can be attained in MFTF-B. The code solves for the electron and ion densities and temperatures in the central cell, yin-yang, barrier, and A-cell regions as well as the plasma potential in each region. In these studies, the A-cell sloshing ion beams were fixed while the neutral beams in the yin-yang and central cell, the gas feed in the central cell, and the applied ECRH power ..beta.., central cell ion density and temperature, and the confining potential are discussed.

  6. Central blood pressure and chronic kidney disease

    PubMed Central

    Ohno, Yoichi; Kanno, Yoshihiko; Takenaka, Tsuneo

    2016-01-01

    In this review, we focused on the relationship between central blood pressure and chronic kidney diseases (CKD). Wave reflection is a major mechanism that determines central blood pressure in patients with CKD. Recent medical technology advances have enabled non-invasive central blood pressure measurements. Clinical trials have demonstrated that compared with brachial blood pressure, central blood pressure is a stronger risk factor for cardiovascular (CV) and renal diseases. CKD is characterized by a diminished renal autoregulatory ability, an augmented direct transmission of systemic blood pressure to glomeruli, and an increase in proteinuria. Any elevation in central blood pressure accelerates CKD progression. In the kidney, interstitial inflammation induces oxidative stress to handle proteinuria. Oxidative stress facilitates atherogenesis, increases arterial stiffness and central blood pressure, and worsens the CV prognosis in patients with CKD. A vicious cycle exists between CKD and central blood pressure. To stop this cycle, vasodilator antihypertensive drugs and statins can reduce central blood pressure and oxidative stress. Even in early-stage CKD, mineral and bone disorders (MBD) may develop. MBD promotes oxidative stress, arteriosclerosis, and elevated central blood pressure in patients with CKD. Early intervention or prevention seems necessary to maintain vascular health in patients with CKD. PMID:26788468

  7. The deglaciation of Central Scandinavia

    NASA Astrophysics Data System (ADS)

    Faulkner, T. L.

    2009-12-01

    'Central Scandinavia' extends from the Norwegian coast across the Helgeland Nappe Complex to the Caledonide thrust front in Sweden (Faulkner, 2005, who studied the effects of Weichselian deglaciation on the speleogenesis of ~1000 local Caledonide marble caves). Deglaciation was driven by two summer heat fluxes: warming by the sea as it encroached up fjords and caused the icesheet margin to retreat eastwards (accompanied by deglacial seismicity) and direct solar warming that caused the icesheet to ablate from its upper surface (Grønlie, 1975; Mörner, 1979; Andersen and Karlsen, 1986; Sørensen et al., 1987; Mangerud, 1991; Bergstrøm, 1995). The melting height followed an empirical parabolic time relationship (H=0.75t2: Grønlie, 1975), based on many geomorphological observations. Faulkner (2005) reconstructed the Grønlie formula using information about the Younger Dryas (YD) isostatic uplift that increased inland as: H=1700+5(YD isobase-220)-0.75x10-4x(13500-t)2 m, where t=14Ca BP. Deglaciation was modelled by drawing deglacial maps at c. 300a intervals that show the advance of the sea, the recession of the icesheet margin, the synchronous thinning of the icesheet, and the evolution of ice-dammed lakes (IDLs), after the ice began to melt vigorously in the Bølling interstadial below the present 1700m altitude (at the 220m YD isobase at Børgefjell) that was already ice-free. After c. 11ka BP, the melting height lowered at roughly 0.5ma-1 at all isobases. The formula agrees with many marine dates to within 300a in the central and northern part of the area, but downwasting by calving was much faster along the coast, as the sea submerged large areas of the isostatically-depressed strandflat. Across the Swedish border, there is evidence that large IDLs and glaciers remained longer than predicted. Most of the area was systematically flooded by glacial meltwater for periods of 800-120014Ca during deglaciation as local IDLs lowered and coalesced (commonly at j

  8. Geology of offshore central California

    SciTech Connect

    McCulloch, D.S.; Lewis, S.D.

    1988-03-01

    The offshore central California margin records Mesozoic and Cenozoic events attributable to continental and oceanic plate interactions. Terranes, some carried thousands of kilometers northward on the Kula and/or Farallon plates, were accreted to North America by late Eocene. Following accretion to North America, terranes along the margin were silvered and redistributed by strike-slip motion along the San Andreas and related faults. During Oligocene global low sea level, much of the coastal margin was subareal and erosion stripped Upper Cretaceous and Eocene strata from elevated basement blocks. These basement blocks subsequently subsided along large-displacement near-coastal faults, and shallow-water marine upper Oligocene and/or lower Miocene volcanics on the present shelf were covered by hemipelagic sediment at bathyal to mid-bathyal depths. This subsidence coincided with tectonism and significant changes in water depth elsewhere around the Pacific margin, and may have been related to a change in Pacific and North American plate relative motion that produced transtensional motion along the California margin. Transtension may have initiated both rupture and volcanism along the San Andreas fault system at about 23 Ma and wrench tectonic deformation on the shelf. During the late Miocene, growing structural highs on the shelf edge formed elongate shelf basins. A compressional component in Pacific and North America plate relative motion, which began between 5 and 3 Ma, produced strike-parallel folds and compressional faults that now dominate the structural grain of the offshore basins. Continued compressive deformation along coastal California is documented by active thrust faults, rapid coastal uplift, and earthquake focal mechanism solutions indicative of northeast-southwest compression.

  9. Historical Seismicity of Central Panama

    NASA Astrophysics Data System (ADS)

    Camacho, E.

    2013-05-01

    Central Panama lies in the Panama microplate, neighboring seismically active regions of Costa Rica and Colombia. This region, crossed by the Panama Canal, concentrates most of the population and economic activity of the Republic of Panama. Instrumental observation of earthquakes in Panama began on 1882 by the Compagnie Universelle du Canal Interocéanique de Panama and continued from 1904 to 1977 by the Panama Canal Company. From October 1997 to March 1998 the USGS deployed a temporary digital seismic network. Since 2003 this region is monitored by a digital seismic network operated by the Panama Canal Authority and I complemented by the broad band stations of the University of Panama seismic network. The seismicity in this region is very diffuse and the few events which are recorded have magnitudes less than 3.0. Historical archives and antique newspapers from Spain, Colombia, Panama and the United Sates have been searched looking for historical earthquake information which could provide a better estimate of the seismicity in this region. We find that Panama City has been shaken by two destructive earthquakes in historical times. One by a local fault (i.e. Pedro Miguel fault) on May 2, 1621 (I=Vlll MM), and a subduction event from the North Panama Deformed Belt (NPDB) on September 7, 1882 (I=Vll MM). To test these findings two earthquakes scenarios were generated, using SELENA, for Panama City Old Quarter. Panama City was rebuilt on January 21, 1673, on a rocky point facing the Pacific Ocean after the sack by pirate Morgan on January 28, 1671. The pattern of damage to calicanto (unreinforced colonial masonry) and wood structures for a crustal local event are higher than those for an event from the NPDB and seem to confirm that the city has not been shaken by a major local event since May 2, 1621 and a subduction event since September 7, 1882

  10. Centralized consolidation/recycling center

    SciTech Connect

    St. Georges, L.T.; Poor, A.D.

    1995-05-01

    There are approximately 175 separate locations on the Hanford Site where dangerous waste is accumulated in hundreds of containers according to compatibility. Materials that are designated as waste could be kept from entering the waste stream by establishing collection points for these materials and wastes and then transporting them to a centralized consolidation/recycling center (hereinafter referred to as the consolidation center). Once there the materials would be prepared for offsite recycling. This document discusses the removal of batteries, partially full aerosol cans, and DOP light ballasts from the traditional waste management approach, which eliminates 89 satellite accumulation areas from the Hanford Site (43 for batteries, 33 for aerosols, and 13 for DOP ballasts). Eliminating these 89 satellite accumulation areas would reduce by hundreds the total number of containers shipped offsite as hazardous waste (due to the increase in containers when the wastes that are accumulated are segregated according to compatibility for final shipment). This new approach is in line with the U.S. Environmental Protection Agency`s (EPA) draft Universal Waste Rules for these {open_quotes}nuisance{close_quotes} and common waste streams. Additionally, future reviews of other types of wastes that can be handled in this less restrictive and more cost-effective manner will occur as part of daily operations at the consolidation center. The Hanford Site has been identified as a laboratory for reinventing government by the Secretary of the U.S. Department of Energy (DOE), Hazel O`Leary, and as a demonstration zone where {open_quotes}innovative ideas, processes and technologies can be created, tested and demonstrated.{close_quotes} Additionally, DOE, EPA, and the Washington State Department of Ecology (Ecology) have agreed to cut Hanford cleanup costs by $1 billion over a 5-year period.

  11. Tethyan evolution of central Asia

    SciTech Connect

    Sengor, A.M.C. )

    1990-05-01

    The study area extends from the eastern shores of the Caspian Sea in the west to the Helan Shan and Longmen Shan in the east and from about 40{degree}N parallel in the north to the neo-Tethyan sutures in the south, thus including what is called Middle Asia in the Soviet literature. In the region thus delineated lies the boundary between the largely late Paleozoic core of Asia (Altaids) and the Tethyside superorogenic complex. This boundary passes through continental objects that collided with nuclear Asia in the late Paleozoic to terminate its Altaid evolution. Subduction to the south of some of these had commenced before they collided (e.g., Tarim in the Kuen-Lun), in others later (e.g., South Ghissar area west of Pamirs). This subduction 1ed, in the late Paleozoic, to the opening of marginal basins, at least one of which may be partly extant (Tarim). Giant subduction accretion complexes of Paleozoic to earliest Triassic age dominate farther south in the basement of Turan (mainly in Turkmenian SSR) and in the Kuen-Lun/Nan Shan ranges. No discrete continental collisions or any continental basement in these regions could be unequivocally recognized contrary to most current interpretations. Magmatic arcs that developed along the southern margin of Asia in the late Paleozoic to early Mesozoic grew atop these subduction-accretion complexes and record a gradual southerly migration of magmatism through time. Subduction also dominated the northern margin of Gondwanaland between Iran and China in late Paleozoic time, although the record in Afghanistan and northwest Tibet is scrappy. It led to back-arc basin formation, which in Iran and Oman became neo-Tethys and, in at least parts of central Asia, the Waser-Mushan-Pshart/Banggong Co-Nu Jiang ocean. This ocean was probably connected with the Omani part of the neo-Tethys via the Sistan region.

  12. 12 CFR 234.4 - Standards for central securities depositories and central counterparties.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... disclosed, and permit fair and open access. (3) The central securities depository or central counterparty holds assets in a manner whereby risk of loss or of delay in its access to them is minimized. Assets...

  13. 12 CFR 234.4 - Standards for central securities depositories and central counterparties.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... disclosed, and permit fair and open access. (3) The central securities depository or central counterparty holds assets in a manner whereby risk of loss or of delay in its access to them is minimized. Assets...

  14. The Latino Experience in Central Falls

    ERIC Educational Resources Information Center

    Holland, William R.

    2011-01-01

    Central Falls is, by far, the poorest community in Rhode Island. More than 40 percent of the children under 18 live in poverty, and 40 percent of that group live in severe poverty. At Central Falls High School, low-income Latino students have fallen behind their white counterparts, with shockingly low graduation, poor literacy, and low…

  15. Traveling Policies: Hijacked in Central Asia

    ERIC Educational Resources Information Center

    Silova, Iveta

    2005-01-01

    Since the collapse of the Soviet Union, Central Asian education reform discourses have become increasingly similar to distinctive Western policy discourses traveling globally across national boundaries. Tracing the trajectory of "traveling policies" in Central Asia, this article discusses the way Western education discourses have been…

  16. 32 CFR 154.41 - Central adjudication.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PERSONNEL SECURITY PROGRAM REGULATION Adjudication § 154.41 Central adjudication. (a) To ensure uniform... Defense Agencies shall establish a single Central Adjudication Facility for his/her component. The... to act on behalf of the head of the Component concerned with respect to personnel...

  17. 32 CFR 154.41 - Central adjudication.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PERSONNEL SECURITY PROGRAM REGULATION Adjudication § 154.41 Central adjudication. (a) To ensure uniform... Defense Agencies shall establish a single Central Adjudication Facility for his/her component. The... to act on behalf of the head of the Component concerned with respect to personnel...

  18. External Review Teams Training in Central America

    ERIC Educational Resources Information Center

    Silva-Trivino, Moises; Ramirez-Gatica, Soledad

    2004-01-01

    Many Latin American countries have started actions to promote a higher education quality assurance system. Central America appears as a regional effort that includes universities from all seven countries under the initiative of Central American University Higher Council (CSUCA). After focusing in quality management and self-study processes, CSUCA…

  19. Connecting Students, Creating Futures at Central Campus

    ERIC Educational Resources Information Center

    Rosin, Julie; Erbes, Elizabeth; Britt, James; Good, Bill

    2012-01-01

    Des Moines is an urban community located in the heart of Iowa. Des Moines Public Schools serves 32,000 students in a system with 62 buildings, including Central Campus--a Regional Academy. Central Campus is housed in four buildings, including the main campus at 1800 Grand located on the western edge of downtown Des Moines. As a regional academy,…

  20. Investigation of differential evolution using temporal centralities

    NASA Astrophysics Data System (ADS)

    Tomaszek, Lukas; Zelinka, Ivan

    2017-07-01

    In this article we are continuing in our research to show mutual intersection of two different areas of research: complex network and evolutionary computation. In this article we briefly describe cost functions and temporal centralities, than we show how to convert differential evolution into complex network and show plots for temporal centralities for two selected functions.

  1. Raising the Bar in Central America

    ERIC Educational Resources Information Center

    Campbell, Monica

    2007-01-01

    Several years ago, students in Central America rarely leave their countries to find work elsewhere. Such is the case of Sebastian Pinto who felt that his degree would not mean much beyond Guatemala, his country. But now, universities in Central American have started to offer regionally accredited degrees that would allow students' credentials to…

  2. Tree biomass in the North Central Region.

    Treesearch

    Gerhard K. Raile; Pamela J. Jakes

    1982-01-01

    Methods for calculating tree biomass are outlined, and the biomass on commercial forest land is estimated for 11 north-central states. Tree biomass in the North Central Region totals 3.6 billion tons, or 50 tons per commercial forest acre. For all species, total tree biomass is concentrated in growing-stock boles.

  3. Comment on ``Subgraph centrality in complex networks''

    NASA Astrophysics Data System (ADS)

    Stevanović, Dragan

    2013-08-01

    We disprove a conjecture of Estrada and Rodríguez-Velázquez [Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.71.056103 71, 056103 (2005)] that if a graph has identical subgraph centrality for all nodes, then the closeness and betweenness centralities are also identical for all nodes.

  4. Visualizing the Central Limit Theorem through Simulation

    ERIC Educational Resources Information Center

    Ruggieri, Eric

    2016-01-01

    The Central Limit Theorem is one of the most important concepts taught in an introductory statistics course, however, it may be the least understood by students. Sure, students can plug numbers into a formula and solve problems, but conceptually, do they really understand what the Central Limit Theorem is saying? This paper describes a simulation…

  5. External Review Teams Training in Central America

    ERIC Educational Resources Information Center

    Silva-Trivino; Moises; Ramirez-Gatica, Soledad

    2004-01-01

    Many Latin American countries have started actions to promote a higher education quality assurance system. Central America appears as a regional effort that includes universities from all seven countries under the initiative of Central American University Higher Council (CSUCA). After focusing in quality management and self-study processes, CSUCA…

  6. Lymphatic Leak Complicating Central Venous Catheter Insertion

    SciTech Connect

    Barnacle, Alex M. Kleidon, Tricia M.

    2005-12-15

    Many of the risks associated with central venous access are well recognized. We report a case of inadvertent lymphatic disruption during the insertion of a tunneled central venous catheter in a patient with raised left and right atrial pressures and severe pulmonary hypertension, which led to significant hemodynamic instability. To our knowledge, this rare complication is previously unreported.

  7. Voices from the Field: Central Office Administrators

    ERIC Educational Resources Information Center

    Dickson, Ken

    2015-01-01

    School systems' central office administrators sometimes take paths that seem easiest, even when it is clear the paths will not lead to sustained positive results that are needed--particularly in terms of twice-exceptional (2e) students. To appropriately address the needs of 2e learners, we must ensure that central office administrative services…

  8. Centralized scheduling an unanticipated revenue cycle opportunity.

    PubMed

    O'Neill, Daniel P; Kenniff, Peter B

    2007-09-01

    Centralized outpatient scheduling can provide acute care hospitals with accessibility and service levels equal to freestanding facilities, enabling hospitals to recapture lost market share. Two implementation strategies are critical to the success of centralized scheduling: Correctly developing the schedule. Managing the incoming call volume.

  9. South Central California Coastline and Channel Islands

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This distant and very oblique image of the south Central California Coastline and Channel Islands (35.0N, 119.0W) offers a spectacular and scenic view of the southern west coast, the central San Joaquin Valley, the entire Sierra Nevada Range and across the southwest to the Rocky Mountains on the horizon.

  10. Forest statistics of central and northern Indiana

    Treesearch

    The Forest Survey Organization. Central States Forest Experiment Station

    1952-01-01

    The Forest Survey is conducted in the various regions by the forest experiment stations of the Forest Service. In Indiana the project is directed by the Central States Forest Experiment Station with headquarters in Columbus, Ohio. This Survey Release presents the more significant preliminary statistics on the forest area and timber volume for Central and Northern...

  11. The Role Centrality on Story Category Saliency.

    ERIC Educational Resources Information Center

    Omanson, Richard C.

    Four experiments involving 54 adults were performed to examine the relationship between the effects of story grammar categories and content centrality on subjects' importance ratings, summaries, immediate recall, and delayed recall. Results of the studies indicated that central content units were judged as more important and were better recalled…

  12. Central Falls' Kids First: A Case Study.

    ERIC Educational Resources Information Center

    Tufts Univ., Medford, MA. Center on Hunger, Poverty and Nutrition Policy.

    Central Falls' Kids First, a 3-year initiative was designed to eradicate local childhood hunger through the expansion of federal child nutrition programs in Central Falls, a small, densely populated, ethnically diverse and low-income city in northeastern Rhode Island. A strong community partnership was created and included the office of the city's…

  13. Raising the Bar in Central America

    ERIC Educational Resources Information Center

    Campbell, Monica

    2007-01-01

    Several years ago, students in Central America rarely leave their countries to find work elsewhere. Such is the case of Sebastian Pinto who felt that his degree would not mean much beyond Guatemala, his country. But now, universities in Central American have started to offer regionally accredited degrees that would allow students' credentials to…

  14. Voices from the Field: Central Office Administrators

    ERIC Educational Resources Information Center

    Dickson, Ken

    2015-01-01

    School systems' central office administrators sometimes take paths that seem easiest, even when it is clear the paths will not lead to sustained positive results that are needed--particularly in terms of twice-exceptional (2e) students. To appropriately address the needs of 2e learners, we must ensure that central office administrative services…

  15. Central State University: Phase II Report

    ERIC Educational Resources Information Center

    Ohio Board of Regents, 2012

    2012-01-01

    In accordance with Ohio Amended Substitute House Bill 153, the Chancellor submitted to the state Legislature and the Governor a plan, developed in consultation with Central State University, that assures the Central State Supplement will be used to promote the goals of increasing enrollment, improving course completion, and increasing the number…

  16. Proceedings, 8th Central Hardwood Forest Conference

    Treesearch

    Larry H. McCormick; Kurt W., eds. Gottschalk

    1991-01-01

    Two invited papers, forty-five volunteer papers, and twenty volunteer poster summaries presented at the 8th Central Hardwood Forest Conference. Presentations were on economics, forest amenities, harvesting, utilization, physiology, genetics, ecology, regeneration, silviculture, protection, management, hydrology, soils, nutrient cycling, and hardwood markets of central...

  17. Visualizing the Central Limit Theorem through Simulation

    ERIC Educational Resources Information Center

    Ruggieri, Eric

    2016-01-01

    The Central Limit Theorem is one of the most important concepts taught in an introductory statistics course, however, it may be the least understood by students. Sure, students can plug numbers into a formula and solve problems, but conceptually, do they really understand what the Central Limit Theorem is saying? This paper describes a simulation…

  18. Centralization and Decentralization in American Education Policy

    ERIC Educational Resources Information Center

    DeBoer, Jennifer

    2012-01-01

    This article examines the trend toward centralization in American education policy over the last century through a variety of lenses. The overall picture that emerges is one of a continuous tug-of-war, with national and local policymakers stumbling together toward incrementally more standardized and centralized policies. There is a center of power…

  19. Central Falls' Kids First: A Case Study.

    ERIC Educational Resources Information Center

    Tufts Univ., Medford, MA. Center on Hunger, Poverty and Nutrition Policy.

    Central Falls' Kids First, a 3-year initiative was designed to eradicate local childhood hunger through the expansion of federal child nutrition programs in Central Falls, a small, densely populated, ethnically diverse and low-income city in northeastern Rhode Island. A strong community partnership was created and included the office of the city's…

  20. Traveling Policies: Hijacked in Central Asia

    ERIC Educational Resources Information Center

    Silova, Iveta

    2005-01-01

    Since the collapse of the Soviet Union, Central Asian education reform discourses have become increasingly similar to distinctive Western policy discourses traveling globally across national boundaries. Tracing the trajectory of "traveling policies" in Central Asia, this article discusses the way Western education discourses have been…

  1. South-central Alaska forests: inventory highlights.

    Treesearch

    Sally Campbell; Willem W.S. van Hees; Bert. Mead

    2005-01-01

    This publication presents highlights of a recent south-central Alaska inventory conducted by the Pacific Northwest Research Station Forest Inventory and Analysis Program (USDA Forest Service). South-central Alaska has about 18.5 million acres, of which one-fifth (4 million acres) is forested. Species diversity is greatest in closed and open Sitka spruce forests, spruce...

  2. Central Life Interests and Job Satisfaction.

    ERIC Educational Resources Information Center

    Dubin, Robert; And Others

    Data on central life interests (CLI) and five aspects of job satisfaction were obtained in a sample of bluecollar males and two samples of clerical females. Both a multiple discriminant analysis and a bivariate analysis were performed. The results of these analyses showed that central life interest was significantly related to the total set of job…

  3. Novel central nervous system drug delivery systems.

    PubMed

    Stockwell, Jocelyn; Abdi, Nabiha; Lu, Xiaofan; Maheshwari, Oshin; Taghibiglou, Changiz

    2014-05-01

    For decades, biomedical and pharmaceutical researchers have worked to devise new and more effective therapeutics to treat diseases affecting the central nervous system. The blood-brain barrier effectively protects the brain, but poses a profound challenge to drug delivery across this barrier. Many traditional drugs cannot cross the blood-brain barrier in appreciable concentrations, with less than 1% of most drugs reaching the central nervous system, leading to a lack of available treatments for many central nervous system diseases, such as stroke, neurodegenerative disorders, and brain tumors. Due to the ineffective nature of most treatments for central nervous system disorders, the development of novel drug delivery systems is an area of great interest and active research. Multiple novel strategies show promise for effective central nervous system drug delivery, giving potential for more effective and safer therapies in the future. This review outlines several novel drug delivery techniques, including intranasal drug delivery, nanoparticles, drug modifications, convection-enhanced infusion, and ultrasound-mediated drug delivery. It also assesses possible clinical applications, limitations, and examples of current clinical and preclinical research for each of these drug delivery approaches. Improved central nervous system drug delivery is extremely important and will allow for improved treatment of central nervous system diseases, causing improved therapies for those who are affected by central nervous system diseases.

  4. Connecting Students, Creating Futures at Central Campus

    ERIC Educational Resources Information Center

    Rosin, Julie; Erbes, Elizabeth; Britt, James; Good, Bill

    2012-01-01

    Des Moines is an urban community located in the heart of Iowa. Des Moines Public Schools serves 32,000 students in a system with 62 buildings, including Central Campus--a Regional Academy. Central Campus is housed in four buildings, including the main campus at 1800 Grand located on the western edge of downtown Des Moines. As a regional academy,…

  5. Historic America: The South Central States.

    ERIC Educational Resources Information Center

    Beardsley, Donna A.

    Many sites in the south central states recall the procession of people who came across the continent with the passing frontier. This paper elaborates on several historic sites in the south central United States. The purpose of the paper is to introduce a series of places to the students and teachers of U.S. history. The paper recommends that…

  6. Central station market development strategies for photovoltaics

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Federal market development strategies designed to accelerate the market penetration of central station applications of photovoltaic energy system are analyzed. Since no specific goals were set for the commercialization of central station applications, strategic principles are explored which, when coupled with specific objectives for central stations, can produce a market development implementation plan. The study includes (1) background information on the National Photovoltaic Program, photovoltaic technology, and central stations; (2) a brief market assessment; (3) a discussion of the viewpoints of the electric utility industry with respect to solar energy; (4) a discussion of commercialization issues; and (5) strategy principles. It is recommended that a set of specific goals and objectives be defined for the photovoltaic central station program, and that these goals and objectives evolve into an implementation plan that identifies the appropriate federal role.

  7. Central registry in psychiatry: A structured review

    PubMed Central

    Prakash, Jyoti; Ramakrishnan, TS; Das, R. C.; Srivastava, K.; Mehta, Suresh; Shashikumar, R.

    2014-01-01

    Background: Central registry in psychiatry is being practiced in few countries and has been found useful in research and clinical management. Role of central registry has also expanded over the years. Materials and Methods: All accessible internet database Medline, Scopus, Embase were accessed from 1990 till date. Available data were systematically reviewed in structured manner and analyzed. Results: Central registry was found useful in epidemiological analysis, association studies, outcome studies, comorbidity studies, forensic issue, effective of medication, qualitative analysis etc., Conclusion: Central registry proves to be effective tool in quantitative and qualitative understanding of psychiatry practice. Findings of studies from central registry can be useful in modifying best practice and evidence based treatment in psychiatry. PMID:25535438

  8. AAPT Diagnostic Criteria for Central Neuropathic Pain.

    PubMed

    Widerström-Noga, Eva; Loeser, John D; Jensen, Troels Staehelin; Finnerup, Nanna Brix

    2017-06-27

    Central neuropathic pain, which is pain caused by a lesion or disease of the central somatosensory nervous system, is a serious consequence of spinal cord injury, stroke, multiple sclerosis, and other conditions affecting the central nervous system. A collaborative effort between the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks public-private partnership and the American Pain Society, the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks-American Pain Society Pain Taxonomy (AAPT) initiative, invited a working group to develop diagnostic criteria for central neuropathic pain. The criteria for central neuropathic pain that were developed expand upon existing criteria for neuropathic pain and the International Classification of Diseases 11th Revision draft criteria to ensure consistency. This article focuses on central neuropathic pain associated with spinal cord injury, stroke, and multiple sclerosis, but the AAPT framework can be extended to central pain due to other causes such as traumatic brain injury. The classification of central neuropathic pain is organized according to the AAPT multidimensional framework, specifically: 1) core diagnostic criteria, 2) common features, 3) common medical and psychiatric comorbidities, 4) neurobiological, psychosocial, and functional consequences, and 5) putative neurobiological and psychosocial mechanisms, risk factors, and protective factors. The AAPT chronic central neuropathic pain taxonomy provides a classification for central pain associated with spinal cord injury, stroke, and multiple sclerosis. The diagnostic criteria are organized according to the AAPT multidimensional framework, specifically: 1) core diagnostic criteria, 2) common features, 3) common medical and psychiatric comorbidities, 4) neurobiological, psychosocial, and functional consequences, and 5) putative neurobiological and psychosocial

  9. Central hypothyroidism - a neglected thyroid disorder.

    PubMed

    Beck-Peccoz, Paolo; Rodari, Giulia; Giavoli, Claudia; Lania, Andrea

    2017-10-01

    Central hypothyroidism is a rare and heterogeneous disorder that is characterized by a defect in thyroid hormone secretion in an otherwise normal thyroid gland due to insufficient stimulation by TSH. The disease results from the abnormal function of the pituitary gland, the hypothalamus, or both. Moreover, central hypothyroidism can be isolated or combined with other pituitary hormone deficiencies, which are mostly acquired and are rarely congenital. The clinical manifestations of central hypothyroidism are usually milder than those observed in primary hypothyroidism. Obtaining a positive diagnosis for central hypothyroidism can be difficult from both a clinical and a biochemical perspective. The diagnosis of central hypothyroidism is based on low circulating levels of free T4 in the presence of low to normal TSH concentrations. The correct diagnosis of both acquired (also termed sporadic) and congenital (also termed genetic) central hypothyroidism can be hindered by methodological interference in free T4 or TSH measurements; routine utilization of total T4 or T3 measurements; concurrent systemic illness that is characterized by low levels of free T4 and normal TSH concentrations; the use of the sole TSH-reflex strategy, which is the measurement of the sole level of TSH, without free T4, if levels of TSH are in the normal range; and the diagnosis of congenital hypothyroidism based on TSH analysis without the concomitant measurement of serum levels of T4. In this Review, we discuss current knowledge of the causes of central hypothyroidism, emphasizing possible pitfalls in the diagnosis and treatment of this disorder.

  10. Central Hemodynamics for Management of Arteriosclerotic Diseases.

    PubMed

    Hashimoto, Junichiro

    2017-08-01

    Arteriosclerosis, particularly aortosclerosis, is the most critical risk factor associated with cardiovascular, cerebrovascular, and renal diseases. The pulsatile hemodynamics in the central aorta consists of blood pressure, flow, and stiffness and substantially differs from the peripheral hemodynamics in muscular arteries. Arteriosclerotic changes with age appear earlier in the elastic aorta, and age-dependent increases in central pulse pressure are more marked than those apparent from brachial pressure measurement. Central pressure can be affected by lifestyle habits, metabolic disorders, and endocrine and inflammatory diseases in a manner different from brachial pressure. Central pulse pressure widening due to aortic stiffening increases left ventricular afterload in systole and reduces coronary artery flow in diastole, predisposing aortosclerotic patients to myocardial hypertrophy and ischemia. The widened pulse pressure is also transmitted deep into low-impedance organs such as the brain and kidney, causing microvascular damage responsible for lacunar stroke and albuminuria. In addition, aortic stiffening increases aortic blood flow reversal, which can lead to retrograde embolic stroke and renal function deterioration. Central pressure has been shown to predict cardiovascular events in most previous studies and potentially serves as a surrogate marker for intervention. Quantitative and comprehensive evaluation of central hemodynamics is now available through various noninvasive pressure/flow measurement modalities. This review will focus on the clinical usefulness and mechanistic rationale of central hemodynamic measurements for cardiovascular risk management.

  11. DrugCentral: online drug compendium

    PubMed Central

    Ursu, Oleg; Holmes, Jayme; Knockel, Jeffrey; Bologa, Cristian G.; Yang, Jeremy J.; Mathias, Stephen L.; Nelson, Stuart J.; Oprea, Tudor I.

    2017-01-01

    DrugCentral (http://drugcentral.org) is an open-access online drug compendium. DrugCentral integrates structure, bioactivity, regulatory, pharmacologic actions and indications for active pharmaceutical ingredients approved by FDA and other regulatory agencies. Monitoring of regulatory agencies for new drugs approvals ensures the resource is up-to-date. DrugCentral integrates content for active ingredients with pharmaceutical formulations, indexing drugs and drug label annotations, complementing similar resources available online. Its complementarity with other online resources is facilitated by cross referencing to external resources. At the molecular level, DrugCentral bridges drug-target interactions with pharmacological action and indications. The integration with FDA drug labels enables text mining applications for drug adverse events and clinical trial information. Chemical structure overlap between DrugCentral and five online drug resources, and the overlap between DrugCentral FDA-approved drugs and their presence in four different chemical collections, are discussed. DrugCentral can be accessed via the web application or downloaded in relational database format. PMID:27789690

  12. Centralized drug review processes: are they fair?

    PubMed

    Mitton, Craig R; McMahon, Meghan; Morgan, Steve; Gibson, Jennifer

    2006-07-01

    Numerous countries have implemented centralized drug review processes to assist in making drug coverage decisions. In addition to examining the final recommendations of these bodies, it is also important to ensure fairness in decision making. Accountability for reasonableness is an ethics-based framework for examining the fairness of priority setting processes. The objective of this study was to assess the fairness of four internationally established centralized drug review processes using accountability for reasonableness. Semi-structured telephone interviews were conducted with stakeholders in Canada, New Zealand, Australia and the UK (n=16). Participants were asked to evaluate their country's centralized drug review process against the four conditions of accountability for reasonableness. Each centralized drug review process satisfied at least one of the four ethical conditions, but none satisfied all four conditions. All participants viewed transparency as critical to both the legitimacy and fairness of centralized drug review processes. Additional strides need to be made in each of the four countries under study to improve the fairness of their centralized drug review processes. Ideally, a fair priority setting process should foster constructive stakeholder engagement and enhance the legitimacy of decisions made in assessing pharmaceutical products for funding. As policy makers are under increasing scrutiny in allocating limited resources, fair process should be seen as a critical component of such activity. This study represents the first attempt to conduct an international comparison of the fairness of centralized drug review agencies in the eyes of participating stakeholders.

  13. XNAT Central: Open sourcing imaging research data.

    PubMed

    Herrick, Rick; Horton, William; Olsen, Timothy; McKay, Michael; Archie, Kevin A; Marcus, Daniel S

    2016-01-01

    XNAT Central is a publicly accessible medical imaging data repository based on the XNAT open-source imaging informatics platform. It hosts a wide variety of research imaging data sets. The primary motivation for creating XNAT Central was to provide a central repository to host and provide access to a wide variety of neuroimaging data. In this capacity, XNAT Central hosts a number of data sets from research labs and investigative efforts from around the world, including the OASIS Brains imaging studies, the NUSDAST study of schizophrenia, and more. Over time, XNAT Central has expanded to include imaging data from many different fields of research, including oncology, orthopedics, cardiology, and animal studies, but continues to emphasize neuroimaging data. Through the use of XNAT's DICOM metadata extraction capabilities, XNAT Central provides a searchable repository of imaging data that can be referenced by groups, labs, or individuals working in many different areas of research. The future development of XNAT Central will be geared towards greater ease of use as a reference library of heterogeneous neuroimaging data and associated synthetic data. It will also become a tool for making data available supporting published research and academic articles.

  14. Central Hemodynamics for Management of Arteriosclerotic Diseases

    PubMed Central

    2017-01-01

    Arteriosclerosis, particularly aortosclerosis, is the most critical risk factor associated with cardiovascular, cerebrovascular, and renal diseases. The pulsatile hemodynamics in the central aorta consists of blood pressure, flow, and stiffness and substantially differs from the peripheral hemodynamics in muscular arteries. Arteriosclerotic changes with age appear earlier in the elastic aorta, and age-dependent increases in central pulse pressure are more marked than those apparent from brachial pressure measurement. Central pressure can be affected by lifestyle habits, metabolic disorders, and endocrine and inflammatory diseases in a manner different from brachial pressure. Central pulse pressure widening due to aortic stiffening increases left ventricular afterload in systole and reduces coronary artery flow in diastole, predisposing aortosclerotic patients to myocardial hypertrophy and ischemia. The widened pulse pressure is also transmitted deep into low-impedance organs such as the brain and kidney, causing microvascular damage responsible for lacunar stroke and albuminuria. In addition, aortic stiffening increases aortic blood flow reversal, which can lead to retrograde embolic stroke and renal function deterioration. Central pressure has been shown to predict cardiovascular events in most previous studies and potentially serves as a surrogate marker for intervention. Quantitative and comprehensive evaluation of central hemodynamics is now available through various noninvasive pressure/flow measurement modalities. This review will focus on the clinical usefulness and mechanistic rationale of central hemodynamic measurements for cardiovascular risk management. PMID:28603219

  15. Report of the Central Tracking Group

    SciTech Connect

    Cassel, D.G.; Hanson, G.G.

    1986-10-01

    Issues involved in building a realistic central tracking system for a general-purpose 4..pi.. detector for the SSC are addressed. Such a central tracking system must be capable of running at the full design luminosity of 10/sup 33/ cm/sup -2/s/sup -1/. Momentum measurement was required in a general-purpose 4..pi.. detector. Limitations on charged particle tracking detectors at the SSC imposed by rates and radiation damage are reviewed. Cell occupancy is the dominant constraint, which led us to the conclusion that only small cells, either wires or straw tubes, are suitable for a central tracking system at the SSC. Mechanical problems involved in building a central tracking system of either wires or straw tubes were studied, and our conclusion was that it is possible to build such a large central tracking system. Of course, a great deal of research and development is required. We also considered central tracking systems made of scintillating fibers or silicon microstrips, but our conclusion was that neither is a realistic candidate given the current state of technology. We began to work on computer simulation of a realistic central tracking system. Events from interesting physics processes at the SSC will be complex and will be further complicated by hits from out-of-time bunch crossings and multiple interactions within the same bunch crossing. Detailed computer simulations are needed to demonstrate that the pattern recognition and tracking problems can be solved.

  16. [WN] central stars of planetary nebulae

    NASA Astrophysics Data System (ADS)

    Todt, H.; Peña, M.; Hamann, W.-R.; Gräfener, G.

    2010-11-01

    Hydrogen-deficient central stars are commonly considered as the progenitors of H-deficient white dwarfs. Spectroscopically, many H-deficient central stars resemble massive Wolf-Rayet stars of the carbon sequence and are therefore classified as [WC] stars. The massive WR stars of the nitrogen sequence (WN), however, have no spectroscopic counterpart among the central stars. With PB 8 we found for the first time a central star with a WR-type emission line spectrum that resembles the nitrogen sequence with only a slight enhancement of carbon lines, and therefore we classified this star as [WN/C]. Our analysis reveals that its atmosphere consists mainly of helium, with some hydrogen and only traces of carbon, nitrogen, and oxygen. This is very different from any other Wolf-Rayet type central stars. The results of our analyses, especially the chemical composition, strongly constrains possible scenarios for the formation of PB 8. For the time being, we don't know any path of single-star evolution that could explain this enigmatic central star. In this context, we will also discuss the status of the central star of PMR 5, which is another candidate for a [WN] spectral type.

  17. Current and future centrally acting antitussives☆

    PubMed Central

    Bolser, Donald C.

    2011-01-01

    The purpose of this review is to highlight some important issues regarding current centrally acting antitussive drugs as well as discuss the implications of these matters on the development of future cough suppressants. Drugs that act in the central nervous system to inhibit cough are termed centrally acting and this designation is based exclusively on evidence obtained from animal models. This classification can include drugs that act both at peripheral and central sites following systemic administration. These drugs are intended to reduce the frequency and/or intensity of coughing resulting from disorders of any etiology. There are a number of central cough suppressants identified by their efficacy in animal models and the most prominent of these are codeine and dextromethorphan. Although the exact neural elements on which these drugs act are currently unknown, they are thought to inhibit a functionally identified component of the central system for cough known as the gating mechanism. The efficacy of codeine and dextromethorphan in humans has recently been questioned. These drugs are less effective on cough induced by upper airway disorders than in pathological conditions involving the lower airways in humans. The reasons for this difference in antitussive sensitivity are not clear. We propose that sensory afferents from different regions of the airways actuate coughing in humans by antitussive sensitive and insensitive control elements in the central nervous system. This hypothesis is consistent with results from an animal model in which laryngeal and tracheobronchial cough had different sensitivities to codeine. Other factors that may be very important in the action of central antitussive drugs in humans include the role of sensations produced by a tussigenic stimulus as well as plasticity of central pathways in response to airway inflammation. Resolution of these issues in the human will be a challenging process, but one which will lay the foundation for the

  18. [Functional anatomy of the central nervous system].

    PubMed

    Krainik, A; Feydy, A; Colombani, J M; Hélias, A; Menu, Y

    2003-03-01

    The central nervous system (CNS) has a particular regional functional anatomy. The morphological support of cognitive functions can now be depicted using functional imaging. Lesions of the central nervous system may be responsible of specific symptoms based on their location. Current neuroimaging techniques are able to show and locate precisely macroscopic lesions. Therefore, the knowledge of functional anatomy of the central nervous system is useful to link clinical disorders to symptomatic lesions. Using radio-clinical cases, we present the functional neuro-anatomy related to common cognitive impairments.

  19. Central serous chorioretinopathy after solar eclipse viewing.

    PubMed

    Lee, Allie; Lai, Timothy Y Y

    2010-07-01

    To report a case of central serous chorioretinopathy after solar eclipse viewing. A middle-age man developed a sudden-onset unilateral scotoma after viewing a partial solar eclipse in Hong Kong. Fundus examination, fluorescein angiography, and optical coherence tomography showed features compatible with central serous chorioretinopathy. The patient was managed conservatively and reevaluated periodically. Serial optical coherence tomographic evaluations demonstrated an initial increase in the amount of subretinal fluid which spontaneously resolved 10 weeks after the onset of symptoms. This case demonstrates the possibility of development of central serous chorioretinopathy following solar eclipse viewing.

  20. [Mechanical complication of central venous catheterization].

    PubMed

    Koja, Hiroki; Tokumine, Joho; Sugahara, Kazuhiro

    2007-01-01

    Central venous catheterization is a procedure with a high success rate. However, life-threatening complications are occasionally caused by mechanical injury during the catheterization process. Therefore, surgeons should have sufficient knowledge of the potential complications and the effective use of preventative measures when performing catheterization. We herein review and discuss the mechanical complications previously reported to have occurred in association with central venous catheterization. Comprehensive knowledge about various complication-inducing factors, the ability to make a quick and accurate diagnosis of such complications, and sufficient skill to prevent worsening of these complications can thus help patients from suffering lethal complications due to central venous catheterization.

  1. Central Serous Chorioretinopathy after Solar Eclipse Viewing

    PubMed Central

    Lee, Allie; Lai, Timothy Y Y

    2010-01-01

    Purpose To report a case of central serous chorioretinopathy after solar eclipse viewing. Case Report A middle-age man developed a sudden-onset unilateral scotoma after viewing a partial solar eclipse in Hong Kong. Fundus examination, fluorescein angiography, and optical coherence tomography showed features compatible with central serous chorioretinopathy. The patient was managed conservatively and reevaluated periodically. Serial optical coherence tomographic evaluations demonstrated an initial increase in the amount of subretinal fluid which spontaneously resolved 10 weeks after the onset of symptoms. Conclusion This case demonstrates the possibility of development of central serous chorioretinopathy following solar eclipse viewing. PMID:22737356

  2. Central black hole masses of galaxies

    NASA Astrophysics Data System (ADS)

    Fan, Jun-Hui

    2003-11-01

    In this paper, the stellar velocity dispersions in the host galaxies are used to estimate the central black hole masses for a sample of elliptical galaxies. We find that the central black hole masses are in the range of 10(5.5-9.5)Modot. Based on the estimated masses in this paper and those by Woo & Urry (2002) and the measured host galaxy absolute magnitude, a relation, log (MBH/Modot) = -(0.25±4.3×10-3)MR + (2.98±0.208) is found for central black hole mass and the host galaxy magnitude. Some discussions are presented.

  3. Cellular Mechanisms of Central Nervous Modulation.

    DTIC Science & Technology

    1983-06-30

    achieve selective disruption of the neuroglia in the central nervous system 4 of our experimental animal, the cockroach (Periplaneta americana). Such...RD-A147 878 CELLULAR MECHANISMIS OF CENTRAL NERVOUS MODULATION(U) i/i I CAMBRIDGE UNIV (ENGLAND) DEPT OF ZOOLOGY J E TRENERNE 30 JUN 83 DHJA37-8i-C...BOOBI UNCLASSFE F/G 6/16 NL bi L& 2. MICROCOPY RESOLUTION TEST CHART NATIONA BUJREAUJ OF STANDOW-S1963-A [.1 PI CELLULAR MECHANISMIS OF CENTRAL NERVOUS

  4. Cellular Mechanisms of Central Nervous Modulation.

    DTIC Science & Technology

    1981-12-31

    Schofield, P.K. (1981) Mechanism of ionic homeostasis in the central nervous system of an insect. J. exp. Biol., 95, 61-73. Treherne, J.E., Schofield...P.K. & Lane, N.J. (1982) Physiological and ultra- structural evidence for an extracellular anion matrix in the central nervous system of an insect...AD-R147 875 CELLULAR MECHANISM1S OF CENTRAL NERVOUS tODULATION(U) I/i CAMBRIDGE UNIV (ENGLAND) DEPT OF ZOOLOGY J E TREHERNE 31 DEC 81 DAJA37-Si-C

  5. Erroneous laboratory values obtained from central catheters.

    PubMed

    Johnston, J B; Messina, M

    1991-01-01

    Serious analytic errors in potassium measurements have been identified in blood specimens obtained from newly inserted central catheters. Erroneous elevated readings have been related to interactions of chemistry analyzer electrodes and substances fixed to external and intraluminal walls of the central catheter. Anecdotal summaries of this phenomenon are presented to enable the nurse to recognize potential problems when sampling blood from central catheters. Studies were performed to determine the amount of flush necessary to clear the catheter of interfering residue. To eliminate this potentially hazardous occurrence, recommended flush volumes, nursing implications, and actions are described.

  6. Colorful Central Peak in an Unnamed Crater

    NASA Image and Video Library

    2011-10-05

    The colorful rocks exposed in the central peak visible in this image from NASA Mars Reconnaissance Orbiter probably reflect variations in mineral content that were caused by water activity early in Mars history.

  7. Cohomological invariants of central simple algebras

    NASA Astrophysics Data System (ADS)

    Merkurjev, A. S.

    2016-10-01

    We determine the indecomposable degree 3 cohomological invariants of tuples of central simple algebras with linear relations. Equivalently, we determine the degree 3 reductive cohomological invariants of all split semisimple groups of type A.

  8. NCI Central Review Board Receives Accreditation

    Cancer.gov

    The Association for the Accreditation of Human Research Protection Programs has awarded the NCI Central Institutional Review Board full accreditation. AAHRPP awards accreditation to organizations demonstrating the highest ethical standards in clinical res

  9. Centralized Copying Saves Time and Money.

    ERIC Educational Resources Information Center

    Benson, Paul

    1996-01-01

    Describes how Deer Park School District, Long Island, New York, is saving money while boosting efficiency by centralizing its high-volume printing and duplicating operations. The new arrangement saves space, time, and expenses. (LMI)

  10. Genetics and diagnosis of central diabetes insipidus.

    PubMed

    Bichet, Daniel G

    2012-04-01

    Most of the central diabetes insipidus cases seen in general practice are acquired but the rare cases of hereditary autosomal dominant or recessive neurohypophyseal diabetes insipidus have provided further cellular understanding of the mechanisms responsible for pre-hormone folding, maturation and release. Autosomal dominant central diabetes insipidus is secondary to the toxic accumulation of vasopressin mutants as fibrillar aggregates in the endoplasmic reticulum of hypothalamic magnocellular neurons producing vasopressin. As well, Trpv1(-/-) and Trpv4(-/-) mice have shed new light on the perception of tonicity through the stretch receptors TRPVs expressed both in central and peripheral neurons. The genomic information provided by sequencing the AVP gene is key to the routine care of these patients and, as in other genetic diseases, reduces health costs and provides psychological benefits to patients and families. In addition, simple, inexpensive blood and urine measurements together with clinical characteristics and brain magnetic resonance imaging (MRI) could distinguish between central, nephrogenic and polydipsic cases.

  11. Centralized Copying Saves Time and Money.

    ERIC Educational Resources Information Center

    Benson, Paul

    1996-01-01

    Describes how Deer Park School District, Long Island, New York, is saving money while boosting efficiency by centralizing its high-volume printing and duplicating operations. The new arrangement saves space, time, and expenses. (LMI)

  12. Genetics Home Reference: central precocious puberty

    MedlinePlus

    ... girls and between ages 9 and 14 in boys, girls with central precocious puberty begin exhibiting signs before ... of puberty is even earlier than normal in girls than in boys. Boys with an MKRN3 gene mutation inherited from ...

  13. Random walk centrality in interconnected multilayer networks

    NASA Astrophysics Data System (ADS)

    Solé-Ribalta, Albert; De Domenico, Manlio; Gómez, Sergio; Arenas, Alex

    2016-06-01

    Real-world complex systems exhibit multiple levels of relationships. In many cases they require to be modeled as interconnected multilayer networks, characterizing interactions of several types simultaneously. It is of crucial importance in many fields, from economics to biology and from urban planning to social sciences, to identify the most (or the less) influent nodes in a network using centrality measures. However, defining the centrality of actors in interconnected complex networks is not trivial. In this paper, we rely on the tensorial formalism recently proposed to characterize and investigate this kind of complex topologies, and extend two well known random walk centrality measures, the random walk betweenness and closeness centrality, to interconnected multilayer networks. For each of the measures we provide analytical expressions that completely agree with numerically results.

  14. Francis Crick, DNA, and the Central Dogma

    ERIC Educational Resources Information Center

    Olby, Robert

    1970-01-01

    This essay describes how Francis Crick, ex-physicist, entered the field of biology and discovered the structure of DNA. Emphasis is upon the double helix, the sequence hypothesis, the central dogma, and the genetic code. (VW)

  15. Central exclusive production and the Durham model

    NASA Astrophysics Data System (ADS)

    Harland-Lang, L. A.; Khoze, V. A.; Ryskin, M. G.

    2014-11-01

    We review some selected results within the Durham model of central exclusive production. We discuss the theoretical aspects of this approach and consider the phenomenological implications for a selection of processes.

  16. A perturbative approach to central exclusive production

    NASA Astrophysics Data System (ADS)

    Harland-Lang, L. A.; Khoze, V. A.; Ryskin, M. G.

    2015-02-01

    We review some selected results within the Durham model of central exclusive production. We present a detailed discussion of this theoretical approach for modeling exclusive processes and we briefly review some of its phenomenological applications.

  17. Central respiratory failure during acute organophosphate poisoning.

    PubMed

    Carey, Jennifer L; Dunn, Courtney; Gaspari, Romolo J

    2013-11-01

    Organophosphate (OP) pesticide poisoning is a global health problem with over 250,000 deaths per year. OPs affect neuronal signaling through acetylcholine (Ach) neurotransmission via inhibition of acetylcholinesterase (AChE), leading to accumulation of Ach at the synaptic cleft and excessive stimulation at post-synaptic receptors. Mortality due to OP agents is attributed to respiratory dysfunction, including central apnea. Cholinergic circuits are integral to many aspects of the central control of respiration, however it is unclear which mechanisms predominate during acute OP intoxication. A more complete understanding of the cholinergic aspects of both respiratory control as well as neural modification of pulmonary function is needed to better understand OP-induced respiratory dysfunction. In this article, we review the physiologic mechanisms of acute OP exposure in the context of the known cholinergic contributions to the central control of respiration. We also discuss the potential central cholinergic contributions to the known peripheral physiologic effects of OP intoxication.

  18. Francis Crick, DNA, and the Central Dogma

    ERIC Educational Resources Information Center

    Olby, Robert

    1970-01-01

    This essay describes how Francis Crick, ex-physicist, entered the field of biology and discovered the structure of DNA. Emphasis is upon the double helix, the sequence hypothesis, the central dogma, and the genetic code. (VW)

  19. Overview of Glutamatergic Dysregulation in Central Pathologies

    PubMed Central

    Miladinovic, Tanya; Nashed, Mina G.; Singh, Gurmit

    2015-01-01

    As the major excitatory neurotransmitter in the mammalian central nervous system, glutamate plays a key role in many central pathologies, including gliomas, psychiatric, neurodevelopmental, and neurodegenerative disorders. Post-mortem and serological studies have implicated glutamatergic dysregulation in these pathologies, and pharmacological modulation of glutamate receptors and transporters has provided further validation for the involvement of glutamate. Furthermore, efforts from genetic, in vitro, and animal studies are actively elucidating the specific glutamatergic mechanisms that contribute to the aetiology of central pathologies. However, details regarding specific mechanisms remain sparse and progress in effectively modulating glutamate to alleviate symptoms or inhibit disease states has been relatively slow. In this report, we review what is currently known about glutamate signalling in central pathologies. We also discuss glutamate’s mediating role in comorbidities, specifically cancer-induced bone pain and depression. PMID:26569330

  20. Central Station DHC Phase 1 feasibility

    SciTech Connect

    Henderson, H.L.

    1992-03-01

    This project assisted a private real estate developer in technically assessing the feasibility of integrating a central DHC system into a proposed 72 acre area mixed-use Planned Development (Central Station) just south of the Chicago Central Business District (Loop). The technical assessment concluded that a district heating and cooling system for Central Station will be feasible, provided that a major anchor load can be connected to the system. The system conceived for the site employs a modular approach that adjusts production capacity to actual load growth. The design concept includes gas-fired boilers for heating, gas turbine driven chillers for base loading, electric motor driven chillers for peaking, steam turbines for peak power and back pressure operation, and chilled water storage. Energy will be supplied to the users in the form of steam or low temperature hot water for heating, and low temperature chilled water for cooling.

  1. Proceedings. 14th Central Hardwood Forest Conference

    Treesearch

    Daniel A. Yaussy; David M. Hix; Robert P. Long; P. Charles, eds. Goebel

    2004-01-01

    Proceedings of the 14th Central Hardwood Forest conference held 16-19 March in Wooster Ohio. Includes 102 papers and abstracts dealing with silviculture, wildlife, human dimensions, harvesting and utilization, physiology, genetics, soils, nutrient cycling, and biometrics.

  2. Initial TMX central-cell ICRH experiments

    SciTech Connect

    Molvik, A.W.; Coffield, F.E.; Falabella, S.; Griffin, D.; McVey, B.; Pickles, W.; Poulsen, P.; Simonen, T.C.; Yugo, J.

    1980-12-09

    Four topics are discussed in this report: the feasibility of applying ion cyclotron resonance heating (ICRH) in the TMX central cell, some applications of heating, the results of preliminary experiments, and plans for further ICRH experiments.

  3. The CMS central hadron calorimeter: Update

    SciTech Connect

    Freeman, J.

    1998-06-01

    The CMS central hadron calorimeter is a brass absorber/ scintillator sampling structure. We describe details of the mechanical and optical structure. We also discuss calibration techniques, and finally the anticipated construction schedule.

  4. Space Radar Image of Tuva, Central Asia

    NASA Image and Video Library

    1999-04-15

    This spaceborne radar image shows part of the remote central Asian region of Tuva, an autonomous republic of the Russian Federation. Tuva is a mostly mountainous region that lies between western Mongolia and southern Siberia.

  5. A handbook for solar central receiver design

    SciTech Connect

    Falcone, P.K.

    1986-12-01

    This Handbook describes central receiver technology for solar thermal power plants. It contains a description and assessment of the major components in a central receiver system configured for utility scale production of electricity using Rankine-cycle steam turbines. It also describes procedures to size and optimize a plant and discussed examples from recent system analyses. Information concerning site selection criteria, cost estimation, construction, and operation and maintenance is also included, which should enable readers to perform design analyses for specific applications.

  6. Gullies in a Central Pit Crater

    NASA Image and Video Library

    2015-10-14

    Sometimes a central pit forms inside some Martian craters, especially when there substantial ground ice. Such is the case in this observation from NASA Mars Reconnaissance Orbiter spacecraft. Sometimes what we call "mass wasting" processes (think small avalanches or landslides) occur on the slopes of the central pit. We took this image to search for any recent activity that would add to or modify previously identified gullies. http://photojournal.jpl.nasa.gov/catalog/PIA20005

  7. Central neurocytoma: establishment of the disease entity.

    PubMed

    Kim, Dong Gyu; Park, Chul-Kee

    2015-01-01

    The establishment and identification of central neurocytoma as a distinct disease entity are invaluable in catalyzing investigations of neuronal differentiation in central nervous system tumors. The discovery of neuronal differentiation in neuroepithelial tumors has been extended to extraventricular tumors and potentially to various glial tumors undergoing neuronal differentiation. Understanding the disease spectrum of neuronal and mixed neuronal-glial tumors is important for deciphering the mechanism of gliomagenesis. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Midwifery education in Central-Eastern Europe.

    PubMed

    Mivšek, Polona; Baškova, Martina; Wilhelmova, Radka

    2016-02-01

    Problems in midwifery in many Central-Eastern European countries are very similar; it is possible to speak about the evolving Central-Eastern model of midwifery care. The educational models of this region have a relatively strong theoretical part; however, there is an insufficient practical dimension. Theoretical part of midwifery education in the universities is relatively autonomous and is slowly changing the professional identity of graduates.

  9. Collection development at the NOAA Central Library

    NASA Technical Reports Server (NTRS)

    Quillen, Steve R.

    1994-01-01

    The National Oceanic and Atmospheric Administration (NOAA) Central Library collection, approximately one million volumes, incorporates the holdings of its predecessor agencies. Within the library, the collections are filed separately, based on their source and/or classification schemes. The NOAA Central Library provides a variety of services to users, ranging from quick reference and interlibrary loan to in-depth research and online data bases.

  10. Neuropathic Pain: Central vs. Peripheral Mechanisms.

    PubMed

    Meacham, Kathleen; Shepherd, Andrew; Mohapatra, Durga P; Haroutounian, Simon

    2017-06-01

    Our goal is to examine the processes-both central and peripheral-that underlie the development of peripherally-induced neuropathic pain (pNP) and to highlight recent evidence for mechanisms contributing to its maintenance. While many pNP conditions are initiated by damage to the peripheral nervous system (PNS), their persistence appears to rely on maladaptive processes within the central nervous system (CNS). The potential existence of an autonomous pain-generating mechanism in the CNS creates significant implications for the development of new neuropathic pain treatments; thus, work towards its resolution is crucial. Here, we seek to identify evidence for PNS and CNS independently generating neuropathic pain signals. Recent preclinical studies in pNP support and provide key details concerning the role of multiple mechanisms leading to fiber hyperexcitability and sustained electrical discharge to the CNS. In studies regarding central mechanisms, new preclinical evidence includes the mapping of novel inhibitory circuitry and identification of the molecular basis of microglia-neuron crosstalk. Recent clinical evidence demonstrates the essential role of peripheral mechanisms, mostly via studies that block the initially damaged peripheral circuitry. Clinical central mechanism studies use imaging to identify potentially self-sustaining infra-slow CNS oscillatory activity that may be unique to pNP patients. While new preclinical evidence supports and expands upon the key role of central mechanisms in neuropathic pain, clinical evidence for an autonomous central mechanism remains relatively limited. Recent findings from both preclinical and clinical studies recapitulate the critical contribution of peripheral input to maintenance of neuropathic pain. Further clinical investigations on the possibility of standalone central contributions to pNP may be assisted by a reconsideration of the agreed terms or criteria for diagnosing the presence of central sensitization in humans.

  11. Single fibre electromyography in central core disease

    PubMed Central

    Martínez, A. Cruz; Ferrer, M. T.; López-Terradas, J. M.; Pascual-Castroviejo, I.; Mingo, P.

    1979-01-01

    Single fibre electromyography in the extensor digitorum communis muscle was studied in five patients with central core disease. The average number of muscle fibre action potentials belonging to the same motor unit was higher in patients than in healthy subjects of the same age. The increase in motor unit fibre density is consistent with increased terminal innervation ratio described in other papers about central core disease. PMID:479907

  12. Centralizing physician office functions. A paradigm shift.

    PubMed

    Croopnick, J G

    1999-01-01

    Recent trends show that organizations that once thought business office centralization was beneficial are re-thinking their strategies and decentralizing business office functions. This article focuses on the paradigm shift from business office centralization to decentralization and the political factors effecting this shift. It provides actual case summaries to demonstrate what has transpired, and presents an alternative strategy to establishing successful business office functions, a hybrid business office.

  13. Central diffractive resonance production at the LHC

    NASA Astrophysics Data System (ADS)

    Fiore, Roberto; Jenkovszky, Laszlo; Schicker, Rainer

    2016-07-01

    Central production of resonances resulting from the scattering of Pomerons in the central rapidity region of proton-proton scattering is studied. Estimates for relevant cross sections are presented. L.J. gratefully acknowledges an EMMI visiting Professorship at the University of Heidelberg for completion of this work. He is grateful to the organizers of this meeting for their hospitality and support. His work was supported also by DOMUS, Hungarian Academy of Sciences

  14. De-centralized and centralized control for realistic EMS Maglev systems

    NASA Astrophysics Data System (ADS)

    Moawad, Mohamed M. Aly M.

    A comparative study of de-centralized and centralized controllers when used with real EMS Maglev Systems is introduced. This comparison is divided into two parts. Part I is concerned with numerical simulation and experimental testing on a two ton six-magnet EMS Maglev vehicle. Levitation and lateral control with these controllers individually and when including flux feedback control in combination with these controllers to enhance stability are introduced. The centralized controller is better than the de-centralized one when the system is exposed to a lateral disturbing force such as wind gusts. The flux feedback control when combined with de-centralized or centralized controllers does improve the stability and is more resistant and robust with respect to the air gap variations. Part II is concerned with the study of Maglev vehicle-girder dynamic interaction system and the comparison between these two controllers on this typical system based on performance and ride quality achieved. Numerical simulations of the ODU EMS Maglev vehicle interacting with girder are conducted with these two different controllers. The de-centralized and centralized control for EMS Maglev systems that interact with a flexible girder provides similar ride quality. Centralized control with flux feedback could be the best controller for the ODU Maglev system when operating on girder. The centralized control will guarantee the suppression of the undesired lateral displacements; hence it will provide smoother ride quality. Flux feedback will suppress air gap variations due to the track discontinuities.

  15. CENTRAL ROTATIONS OF MILKY WAY GLOBULAR CLUSTERS

    SciTech Connect

    Fabricius, Maximilian H.; Rukdee, Surangkhana; Saglia, Roberto P.; Bender, Ralf; Hopp, Ulrich; Thomas, Jens; Williams, Michael J.; Noyola, Eva; Opitsch, Michael

    2014-06-01

    Most Milky Way globular clusters (GCs) exhibit measurable flattening, even if on a very low level. Both cluster rotation and tidal fields are thought to cause this flattening. Nevertheless, rotation has only been confirmed in a handful of GCs, based mostly on individual radial velocities at large radii. We are conducting a survey of the central kinematics of Galactic GCs using the new Integral Field Unit instrument VIRUS-W. We detect rotation in all 11 GCs that we have observed so far, rendering it likely that a large majority of the Milky Way GCs rotate. We use published catalogs of GCs to derive central ellipticities and position angles. We show that in all cases where the central ellipticity permits an accurate measurement of the position angle, those angles are in excellent agreement with the kinematic position angles that we derive from the VIRUS-W velocity fields. We find an unexpected tight correlation between central rotation and outer ellipticity, indicating that rotation drives flattening for the objects in our sample. We also find a tight correlation between central rotation and published values for the central velocity dispersion, most likely due to rotation impacting the old dispersion measurements.

  16. Central Rotations of Milky Way Globular Clusters

    NASA Astrophysics Data System (ADS)

    Fabricius, Maximilian H.; Noyola, Eva; Rukdee, Surangkhana; Saglia, Roberto P.; Bender, Ralf; Hopp, Ulrich; Thomas, Jens; Opitsch, Michael; Williams, Michael J.

    2014-06-01

    Most Milky Way globular clusters (GCs) exhibit measurable flattening, even if on a very low level. Both cluster rotation and tidal fields are thought to cause this flattening. Nevertheless, rotation has only been confirmed in a handful of GCs, based mostly on individual radial velocities at large radii. We are conducting a survey of the central kinematics of Galactic GCs using the new Integral Field Unit instrument VIRUS-W. We detect rotation in all 11 GCs that we have observed so far, rendering it likely that a large majority of the Milky Way GCs rotate. We use published catalogs of GCs to derive central ellipticities and position angles. We show that in all cases where the central ellipticity permits an accurate measurement of the position angle, those angles are in excellent agreement with the kinematic position angles that we derive from the VIRUS-W velocity fields. We find an unexpected tight correlation between central rotation and outer ellipticity, indicating that rotation drives flattening for the objects in our sample. We also find a tight correlation between central rotation and published values for the central velocity dispersion, most likely due to rotation impacting the old dispersion measurements. This Letter includes data taken at The McDonald Observatory of The University of Texas at Austin.

  17. Dynamics-based centrality for directed networks

    NASA Astrophysics Data System (ADS)

    Masuda, Naoki; Kori, Hiroshi

    2010-11-01

    Determining the relative importance of nodes in directed networks is important in, for example, ranking websites, publications, and sports teams, and for understanding signal flows in systems biology. A prevailing centrality measure in this respect is the PageRank. In this work, we focus on another class of centrality derived from the Laplacian of the network. We extend the Laplacian-based centrality, which has mainly been applied to strongly connected networks, to the case of general directed networks such that we can quantitatively compare arbitrary nodes. Toward this end, we adopt the idea used in the PageRank to introduce global connectivity between all the pairs of nodes with a certain strength. Numerical simulations are carried out on some networks. We also offer interpretations of the Laplacian-based centrality for general directed networks in terms of various dynamical and structural properties of networks. Importantly, the Laplacian-based centrality defined as the stationary density of the continuous-time random walk with random jumps is shown to be equivalent to the absorption probability of the random walk with sinks at each node but without random jumps. Similarly, the proposed centrality represents the importance of nodes in dynamics on the original network supplied with sinks but not with random jumps.

  18. Health challenges in Kazakhstan and Central Asia.

    PubMed

    Adambekov, Shalkar; Kaiyrlykyzy, Aiym; Igissinov, Nurbek; Linkov, Faina

    2016-01-01

    The Central Asian region, which encompasses Kazakhstan, Uzbekistan, Tajikistan, Turkmenistan and Kyrgyzstan, is an interesting geographic region with a rich history dating back to the Silk Road, Mongol conquests and expansion of the Russian Empire. However, from a public health viewpoint, the Central Asian region is under-investigated, and many public health challenges exist, as countries of Central Asia inherited the centralised medical systems practiced in the Soviet Union, and are currently undergoing rapid transitions. A large number of low and middle-income countries around the world, including countries of Central Asia, face a double burden of chronic and infectious disease. This essay focuses on the exploration of the most important public health challenges in the Central Asian region, including limited scientific productivity, the double burden of chronic and infectious disease, the need for healthcare reform and the reduction in care variation. Central Asia has a large number of medical schools, medical centres, and emerging research institutes that can be used to foster a change in medical and public health practice in the region.

  19. Community centrality and social science research.

    PubMed

    Allman, Dan

    2015-12-01

    Community centrality is a growing requirement of social science. The field's research practices are increasingly expected to conform to prescribed relationships with the people studied. Expectations about community centrality influence scholarly activities. These expectations can pressure social scientists to adhere to models of community involvement that are immediate and that include community-based co-investigators, advisory boards, and liaisons. In this context, disregarding community centrality can be interpreted as failure. This paper considers evolving norms about the centrality of community in social science. It problematises community inclusion and discusses concerns about the impact of community centrality on incremental theory development, academic integrity, freedom of speech, and the value of liberal versus communitarian knowledge. Through the application of a constructivist approach, this paper argues that social science in which community is omitted or on the periphery is not failed science, because not all social science requires a community base to make a genuine and valuable contribution. The utility of community centrality is not necessarily universal across all social science pursuits. The practices of knowing within social science disciplines may be difficult to transfer to a community. These practices of knowing require degrees of specialisation and interest that not all communities may want or have.

  20. Velocardiofacial syndrome with single central incisor.

    PubMed

    Oberoi, Snehlata; Vargervik, Karin

    2005-01-15

    Three siblings and their mother are reported who all had cytogenetically proven velocardiofacial syndrome (VCFS). One boy had normal dental and craniofacial findings, except for an increased cranial base angle. His sister had only one central incisor in the maxilla. One central incisor had also been missing in the primary dentition. She had no labial frenulum present. Cephalometry showed a small maxillary unit length indicating mild maxillary hypoplasia, an increased anterior face height, steep mandibular plane angle, retruded chin, and a large cranial base angle. Dental measurements showed retroclined lower incisors and increased interincisal angle. A second sister had a cleft of the secondary palate. All permanent teeth were present with the exception of a missing central incisor in the lower jaw: the single lower central incisor was situated in the midline. Her cephalometry showed similar findings as in her sister. All three siblings required palate surgery for speech. Mother was not available for detailed dental and other oral investigations. A single maxillary central incisor has previously been reported in VCFS, but to our knowledge a single central incisor in the mandible has not been reported previously in this entity.

  1. Central auditory function of deafness genes.

    PubMed

    Willaredt, Marc A; Ebbers, Lena; Nothwang, Hans Gerd

    2014-06-01

    The highly variable benefit of hearing devices is a serious challenge in auditory rehabilitation. Various factors contribute to this phenomenon such as the diversity in ear defects, the different extent of auditory nerve hypoplasia, the age of intervention, and cognitive abilities. Recent analyses indicate that, in addition, central auditory functions of deafness genes have to be considered in this context. Since reduced neuronal activity acts as the common denominator in deafness, it is widely assumed that peripheral deafness influences development and function of the central auditory system in a stereotypical manner. However, functional characterization of transgenic mice with mutated deafness genes demonstrated gene-specific abnormalities in the central auditory system as well. A frequent function of deafness genes in the central auditory system is supported by a genome-wide expression study that revealed significant enrichment of these genes in the transcriptome of the auditory brainstem compared to the entire brain. Here, we will summarize current knowledge of the diverse central auditory functions of deafness genes. We furthermore propose the intimately interwoven gene regulatory networks governing development of the otic placode and the hindbrain as a mechanistic explanation for the widespread expression of these genes beyond the cochlea. We conclude that better knowledge of central auditory dysfunction caused by genetic alterations in deafness genes is required. In combination with improved genetic diagnostics becoming currently available through novel sequencing technologies, this information will likely contribute to better outcome prediction of hearing devices.

  2. Community centrality and social science research

    PubMed Central

    Allman, Dan

    2015-01-01

    Community centrality is a growing requirement of social science. The field's research practices are increasingly expected to conform to prescribed relationships with the people studied. Expectations about community centrality influence scholarly activities. These expectations can pressure social scientists to adhere to models of community involvement that are immediate and that include community-based co-investigators, advisory boards, and liaisons. In this context, disregarding community centrality can be interpreted as failure. This paper considers evolving norms about the centrality of community in social science. It problematises community inclusion and discusses concerns about the impact of community centrality on incremental theory development, academic integrity, freedom of speech, and the value of liberal versus communitarian knowledge. Through the application of a constructivist approach, this paper argues that social science in which community is omitted or on the periphery is not failed science, because not all social science requires a community base to make a genuine and valuable contribution. The utility of community centrality is not necessarily universal across all social science pursuits. The practices of knowing within social science disciplines may be difficult to transfer to a community. These practices of knowing require degrees of specialisation and interest that not all communities may want or have. PMID:26440071

  3. Perturbation Centrality and Turbine: A Novel Centrality Measure Obtained Using a Versatile Network Dynamics Tool

    PubMed Central

    Szalay, Kristóf Z.; Csermely, Peter

    2013-01-01

    Analysis of network dynamics became a focal point to understand and predict changes of complex systems. Here we introduce Turbine, a generic framework enabling fast simulation of any algorithmically definable dynamics on very large networks. Using a perturbation transmission model inspired by communicating vessels, we define a novel centrality measure: perturbation centrality. Hubs and inter-modular nodes proved to be highly efficient in perturbation propagation. High perturbation centrality nodes of the Met-tRNA synthetase protein structure network were identified as amino acids involved in intra-protein communication by earlier studies. Changes in perturbation centralities of yeast interactome nodes upon various stresses well recapitulated the functional changes of stressed yeast cells. The novelty and usefulness of perturbation centrality was validated in several other model, biological and social networks. The Turbine software and the perturbation centrality measure may provide a large variety of novel options to assess signaling, drug action, environmental and social interventions. PMID:24205090

  4. Atmospheric stability and diurnal patterns of aeolian saltation on the Llano Estacado

    USDA-ARS?s Scientific Manuscript database

    Aeolian transport is driven by aerodynamic surface stress imposed by turbulent winds in the Earth’s atmospheric boundary layer (ABL). ABL regime is influenced by stratification, which can either enhance or suppress production of turbulence by shear associated with the vertical gradient of streamwise...

  5. Fluid evolution and transport during metamorphism: evidence from the Llano Uplift, Texas

    NASA Astrophysics Data System (ADS)

    Bebout, Gray E.; Carlson, William D.

    1986-04-01

    A field, petrologic and stable isotopic investigation of the marbles and calc-silicates of the 1.15 b.y. Valley Spring Gneiss documents the dilution of internally evolved CO2-rich fluids by externally derived aqueous fluids introduced along channelways. Reaction textures within calcsilicates record the evolution through time of initially CO2-rich fluids toward increasingly more aqueous compositions. Assemblage zonations within calc-silicates require equilibration within local gradients of the mole fraction of CO2 in the fluid, and suggest that the infiltration of aqueous fluids was largely channelized along more permeable lithologies. Localized depletions in 13C and 18O corroborate petrologic evidence for channelized infiltration. Isotopic compositions reflect both devolatilization and the introduction of low- δ 18O fluids; estimated minimum oxygen-equivalent fluid-to-rock ratios are near unity. Both mineralogical and stable isotopic systematics document the essential role of infiltration in driving decarbonation reactions during calc-silicate formation. The calc-silicate assemblages which equilibrated with fluids of the lowest mole fraction of CO2 record isotopic exchange equilibrium with fluids of δ 18O typical of those derived from “normal granites”, as do the granitic aplites and pegmatites which transect most calcsilicate occurrences. Thus the infiltrating fluids are believed to be genetically linked to the intrusion of a suite of granitic plutons emplaced after the peak of regional metamorphism.

  6. [Soil microbial activity variation after land use changes in savannah, Llanos Orientales, Venezuela].

    PubMed

    Gómez, Yrma; Paolini, Jorge

    2011-03-01

    In West plains of Venezuela, the traditional land use of the Trachypogon savannah, has been the extensive grazing. The pressure over these savannahs to obtain a major animal productivity has stimulated the introduction of exotic forage plants, such as Brachiaria brizantha and Andropogon gayanus. In spite that great savannah extensions have been subject to this land use change, information about the effect that pastures and grazing activity have on microbial activity in these soils is scarce. So the objective of this study was to determine the impact that the extensive grazing and cover substitution have on microbial activity. The soil sampling was carried out during the dry and rainy seasons. The employed parameters to determine changes in soil microbial activity were the substrate induced respiration (SIR), basal respiration (BR), the dehydrogenase activity (DHS), the fluorescein diacetate hydrolysis (FDA) and the arginene ammonification (AA). The similarity of the structural soil characteristics studied allows us to infer, that the differences in the microbiological parameters are determined by climatic conditions and soil management. The results show that there is a low microbial activity in these soils. The rainy season caused an increase in all the microbiological parameters determined. B. brizantha made a greater contribution to soil carbon and promoted a greater heterotrophic activity. The extensive grazing and the low stocking rate in the West plain savannas did not affect the microbial activity in these soils.

  7. Feeding chronology of juvenile piranhas, Pygocentrus notatus, in the Venezuelan llanos

    USGS Publications Warehouse

    Nico, L.G.

    1990-01-01

    During the 1988 rainy season, I studied the 24 h feeding chronology of juvenile (40–68 mm standard length) piranhas, Pygocentrus notatus (Characidae: Serrasalminae) from a natural population inhabiting a small savanna stream in Apure State, Venezuela. Stomach contents analyses, supported by laboratory determinations of digestion rate, showed that these fish are primarily diurnal carnivores. Predatory activity on 4–5 August 1988 increased markedly after sunrise, peaked around 1100 h, and essentially stopped after sunset. Means of stomach content weight-to-fish weight ratios among the periods sampled were significantly different. Small fish were the major prey at all hours (81% of total prey volume). Underlying factors responsible for the observed 24 h feeding patterns were not investigated, but avoidance of predation by adult piranhas, which were very active near sunset, may have been important.

  8. GRB Jets with Time Variable Central Engines

    NASA Astrophysics Data System (ADS)

    Morsony, Brian J.; Lazzati, D.; Begelman, M. C.

    2009-01-01

    We study the long-term evolution of relativistic jets in collapsars and examine the effects of time variable energy input on the subsequent gamma ray bursts. We carry out a series of high-resolution simulations of a jet propagating through a stellar envelope in 2D cylindrical coordinates using the FLASH relativistic hydrodynamics module. We carry out a series of simulations of central engines that vary on long time periods, comparable to the breakout time of the jet, short time periods (0.1s) much less than the breakout time, and that decay as a powerlaw at late times. Long period simulations show the opening angle of the jet rapidly adjusts to changes in input energy, in about 0.1s. For short period variability, the structure of the jet is not significantly effected by changes of the central engine output, but the signature of these changes is clearly visible in the energy flux seen by an observer. Short period changes are preserved from the central engine to well outside the star, indicating that short timescale fluctuation seen in prompt GRB emission can be due to central engine activity and will reflect the history of that activity. Models with a decaying energy input have a constant opening angle at late times. This is significant because it allows energy to escape from the central engine to a large radius even with a small energy input at late times, indicating that the central engine could be responsible for the shallow decay seen in X-ray afterglow lightcurves and for X-ray flares. A simulation of a flare from the central engine during the decay phase produces a flare of energy with a sharp rise and decay that is not significantly modified by passing through the stellar envelope.

  9. Microsurgical anatomy of the central lobe.

    PubMed

    Frigeri, Thomas; Paglioli, Eliseu; de Oliveira, Evandro; Rhoton, Albert L

    2015-03-01

    The central lobe consists of the pre- and postcentral gyri on the lateral surface and the paracentral lobule on the medial surface and corresponds to the sensorimotor cortex. The objective of the present study was to define the neural features, craniometric relationships, arterial supply, and venous drainage of the central lobe. Cadaveric hemispheres dissected using microsurgical techniques provided the material for this study. The coronal suture is closer to the precentral gyrus and central sulcus at its lower rather than at its upper end, but they are closest at a point near where the superior temporal line crosses the coronal suture. The arterial supply of the lower two-thirds of the lateral surface of the central lobe was from the central, precentral, and anterior parietal branches that arose predominantly from the superior trunk of the middle cerebral artery. The medial surface and the superior third of the lateral surface were supplied by the posterior interior frontal, paracentral, and superior parietal branches of the pericallosal and callosomarginal arteries. The venous drainage of the superior two-thirds of the lateral surface and the central lobe on the medial surface was predominantly through the superior sagittal sinus, and the inferior third of the lateral surface was predominantly through the superficial sylvian veins to the sphenoparietal sinus or the vein of Labbé to the transverse sinus. The pre- and postcentral gyri and paracentral lobule have a morphological and functional anatomy that differentiates them from the remainder of their respective lobes and are considered by many as a single lobe. An understanding of the anatomical relationships of the central lobe can be useful in preoperative planning and in establishing reliable intraoperative landmarks.

  10. Central retinal vessel blood flow after surgical treatment for central retinal vein occlusion.

    PubMed

    Crama, Niels; Gualino, Vincent; Restori, Marie; Charteris, David G

    2010-01-01

    The purpose of this study was to determine the effect of radial optic neurotomy and retinal endovascular surgery on retinal blood flow velocity in patients with central retinal vein occlusion. A prospective interventional case series. Six patients with a central retinal vein occlusion of <12 months' duration were included. Three patients were treated with radial optic neurotomy and three with retinal endovascular surgery. Five patients had decreased central venous blood flow velocity compared with the fellow eye, and one patient had similar central venous blood flow in both eyes at baseline. All study eyes had decreased central venous blood flow velocity compared with the fellow eye at 24 weeks after treatment. Two patients had a further decrease in central venous blood flow during the study. Three patients had no minimal change in central venous blood flow, and 1 patient showed a minimal increase from 3 cm/s at baseline to 4 cm/s 24 weeks after surgery. Radial optic neurotomy and retinal endovascular surgery do not alter central retinal blood flow velocity. The place of these therapies in the treatment for central retinal vein occlusion should be questioned.

  11. 21 CFR 1305.24 - Central processing of orders.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... or more registered locations and maintains a central processing computer system in which orders are... order with all linked records on the central computer system. (b) A company that has central processing... the company owns and operates....

  12. Central depression of nuclear charge density distribution

    SciTech Connect

    Chu Yanyun; Ren Zhongzhou; Wang Zaijun; Dong Tiekuang

    2010-08-15

    The center-depressed nuclear charge distributions are investigated with the parametrized distribution and the relativistic mean-field theory, and their corresponding charge form factors are worked out with the phase shift analysis method. The central depression of nuclear charge distribution of {sup 46}Ar and {sup 44}S is supported by the relativistic mean-field calculation. According to the calculation, the valence protons in {sup 46}Ar and {sup 44}S prefer to occupy the 1d{sub 3/2} state rather than the 2s{sub 1/2} state, which is different from that in the less neutron-rich argon and sulfur isotopes. As a result, the central proton densities of {sup 46}Ar and {sup 44}S are highly depressed, and so are their central charge densities. The charge form factors of some argon and sulfur isotopes are presented, and the minima of the charge form factors shift upward and inward when the central nuclear charge distributions are more depressed. Besides, the effect of the central depression on the charge form factors is studied with a parametrized distribution, when the root-mean-square charge radii remain constant.

  13. Geometry of complex networks and topological centrality

    NASA Astrophysics Data System (ADS)

    Ranjan, Gyan; Zhang, Zhi-Li

    2013-09-01

    We explore the geometry of complex networks in terms of an n-dimensional Euclidean embedding represented by the Moore-Penrose pseudo-inverse of the graph Laplacian (L). The squared distance of a node i to the origin in this n-dimensional space (lii+), yields a topological centrality index, defined as C∗(i)=1/lii+. In turn, the sum of reciprocals of individual node centralities, ∑i1/C∗(i)=∑ilii+, or the trace of L, yields the well-known Kirchhoff index (K), an overall structural descriptor for the network. To put into context this geometric definition of centrality, we provide alternative interpretations of the proposed indices that connect them to meaningful topological characteristics - first, as forced detour overheads and frequency of recurrences in random walks that has an interesting analogy to voltage distributions in the equivalent electrical network; and then as the average connectedness of i in all the bi-partitions of the graph. These interpretations respectively help establish the topological centrality (C∗(i)) of node i as a measure of its overall position as well as its overall connectedness in the network; thus reflecting the robustness of i to random multiple edge failures. Through empirical evaluations using synthetic and real world networks, we demonstrate how the topological centrality is better able to distinguish nodes in terms of their structural roles in the network and, along with Kirchhoff index, is appropriately sensitive to perturbations/re-wirings in the network.

  14. Central Venous Occlusion in the Hemodialysis Patient.

    PubMed

    Krishna, Vinay Narasimha; Eason, Joseph B; Allon, Michael

    2016-11-01

    Central venous stenosis (CVS) is encountered frequently among hemodialysis patients. Prior ipsilateral central venous catheterization and cardiac rhythm device insertions are common risk factors, but CVS can also occur in the absence of this history. Chronic CVS can cause thrombosis with partial or complete occlusion of the central vein at the site of stenosis. CVS is frequently asymptomatic and identified as an incidental finding during imaging studies. Symptomatic CVS presents most commonly as an upper- or lower-extremity edema ipsilateral to the CVS. Previously unsuspected CVS may become symptomatic after placement of an ipsilateral vascular access. The likelihood of symptomatic CVS may be affected by the central venous catheter (CVC) location; CVC side; duration of CVC dependence; type, location, and blood flow of the ipsilateral access; and extent of collateral veins. Venous angiography is the gold standard for diagnosis. Percutaneous transluminal angioplasty and stent placement can improve the stenosis and alleviate symptoms, but CVS typically recurs frequently, requiring repeated interventions. Refractory symptomatic CVS may require ligation of the ipsilateral vascular access. Because no available treatment option is curative, the goal should be to prevent CVS by minimizing catheters and central vein instrumentation in patients with chronic kidney disease and dialysis patients. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  15. Central nervous system complications after liver transplantation.

    PubMed

    Kim, Jeong-Min; Jung, Keun-Hwa; Lee, Soon-Tae; Chu, Kon; Roh, Jae-Kyu

    2015-08-01

    We investigated the diversity of central nervous system complications after liver transplantation in terms of clinical manifestations and temporal course. Liver transplantation is a lifesaving option for end stage liver disease patients but post-transplantation neurologic complications can hamper recovery. Between 1 January 2001 and 31 December 2010, patients who had undergone liver transplantation at a single tertiary university hospital were included. We reviewed their medical records and brain imaging data and classified central nervous system complications into four categories including vascular, metabolic, infectious and neoplastic. The onset of central nervous system complications was grouped into five post-transplantation intervals including acute (within 1 month), early subacute (1-3 months), late subacute (3-12 months), chronic (1-3 years), and long-term (after 3 years). During follow-up, 65 of 791 patients (8.2%) experienced central nervous system complications, with 30 occurring within 1 month after transplantation. Vascular etiology was the most common (27 patients; 41.5%), followed by metabolic (23; 35.4%), infectious (nine patients; 13.8%), and neoplastic (six patients). Metabolic encephalopathy with altered consciousness was the most common etiology during the acute period, followed by vascular disorders. An initial focal neurologic deficit was detected in vascular and neoplastic complications, whereas metabolic and infectious etiologies presented with non-focal symptoms. Our study shows that the etiology of central nervous system complications after liver transplantation changes over time, and initial symptoms can help to predict etiology.

  16. 1. EXTERIOR OF CENTRAL HEATING STATION, BUILDING 102, LOOKING NORTH. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. EXTERIOR OF CENTRAL HEATING STATION, BUILDING 102, LOOKING NORTH. - Mill Valley Air Force Station, Central Heating Station, East Ridgecrest Boulevard, Mount Tamalpais, Mill Valley, Marin County, CA

  17. The fermilab central computing facility architectural model

    NASA Astrophysics Data System (ADS)

    Nicholls, J.

    1989-12-01

    The goal of the current Central Computing Upgrade at Fermilab is to create a computing enviroment that maximizes total productivity, particularly for high energy physics analysis. The Computing Department and the Next Computer Acquisition Committee decided upon a model which includes five components: an interactive front-end, a LargeScale Scientific Computer (LSSC, a mainframe computing engine), a microprocessor farm system, a file server, and workstations. With the exception of the file server, all segments of this model are currently in production: a VAX/VMS cluster interactive front-end, an Amdahl VM computing engine, ACP farms, and (primary) VMS workstations. This paper will discuss the implemetation of the Fermilab Central Computing Facility Architectural Model. Implications for Code Management in such a heterogeneous environment, including issues such as modularity and centrality, will be considered. Special emphasis will be placed on connectivity and communications between the front-end, LSSC, and workstations, as practiced at Fermilab.

  18. Diagnosis and management of central hypersomnias

    PubMed Central

    Susta, Marek

    2012-01-01

    Central hypersomnias are diseases manifested in excessive daytime sleepiness (EDS) not caused by disturbed nocturnal sleep or misaligned circadian rhythms. Central hypersomnias includes narcolepsy with and without cataplexy, recurrent hypersomnia, idiopathic hypersomnia, with and without long sleep time, behaviorally induced insufficient sleep syndrome, hypersomnia and narcolepsy due to medical conditions, and finally hypersomnia induced by substance intake. The Epworth Sleepiness Scale is a subjective tool mostly used for EDS assessment, while the Multiple Sleep Latency Test serves as an objective diagnostic method for narcolepsy and idiopathic hypersomnias. As for symptomatic therapy of EDS, the central nervous system stimulants modafinil and methylphenidate seem to work well in most cases and in narcolepsy and Parkinson’s disease; sodium oxybate also has notable therapeutic value. PMID:22973425

  19. Effect of sound deprivation on central hearing.

    PubMed

    Welsh, L W; Welsh, J J; Healy, M P

    1983-12-01

    The authors have investigated the thesis that intermittent hearing impairment due to middle ear disease in the early years of life results in a central auditory disturbance which may persist in adulthood. The concept that, during the speech development years, auditory disturbances interfere with the normal maturation of central auditory processing appear to be clearly established. Thirty-five children, free of active ear disease and normally hearing by standard peripheral audiometry, are the basis for the study. The monotic tests employing temporal and frequency distortion and the dichotic challenges of competing stimuli and central integration provide the test data. Approximately 75% of the study group fail at least 1 segment of the battery, beyond 2 standard deviations from the normal data. A decreasing percentage of the study group exceed the normative values in 2 or more of the test components. In view of these data on aggressive program of auditory conservation is suggested during the early years of life.

  20. Dry needling - peripheral and central considerations.

    PubMed

    Dommerholt, Jan

    2011-11-01

    Dry needling is a common treatment technique in orthopedic manual physical therapy. Although various dry needling approaches exist, the more common and best supported approach targets myofascial trigger points. This article aims to place trigger point dry needling within the context of pain sciences. From a pain science perspective, trigger points are constant sources of peripheral nociceptive input leading to peripheral and central sensitization. Dry needling cannot only reverse some aspects of central sensitization, it reduces local and referred pain, improves range of motion and muscle activation pattern, and alters the chemical environment of trigger points. Trigger point dry needling should be based on a thorough understanding of the scientific background of trigger points, the differences and similarities between active and latent trigger points, motor adaptation, and central sensitize application. Several outcome studies are included, as well as comments on dry needling and acupuncture.

  1. Late Quaternary Eolian Deposition in Central Italy

    NASA Astrophysics Data System (ADS)

    Narcisi, Biancamaria

    2000-09-01

    Records of eolian quartz from two continuous sediment sequences drilled in Lagaccione and Lago di Vico volcanic lakes in central Italy contribute to the knowledge of eolian deposition in the central Mediterranean during the last 100,000 years. The chronology is based on 14C and 40Ar/39Ar dating and tephra analysis. Pollen data provide the paleoenvironmental framework and enable correlation between the cores. Eolian inputs were high during the steppe phases corresponding to oxygen isotope stages 4 and 2. Low inputs correspond to the forest phases of the last interglacial and the middle Holocene. Eolian inputs have increased in the late Holocene. Patterns of eolian deposition in central Italy resemble the Antarctic dust record from the Vostok ice core. The Italian patterns may also correspond with hydrological changes registered in North Africa. The main source of dust loading over the Mediterranean now, North Africa, may have played an important role in dust supply throughout the last climatic cycle.

  2. A magnetotelluric profile across Central Java, Indonesia

    NASA Astrophysics Data System (ADS)

    Ritter, O.; Hoffmann-Rothe, A.; Müller, A.; Dwipa, S.; Arsadi, E. M.; Mahfi, A.; Nurnusanto, I.; Byrdina, S.; Echternacht, F.; Haak, V.

    1998-12-01

    Along a N30°E striking profile in central Java, Indonesia we recorded broadband magnetotelluric data at 8 sites in the period range 0.01 s-10000s. A preliminary analysis of apparent resistivity, phase and magnetic transfer function data favours a one-dimensional interpretation of most sites for the upper 3-5 km of the crust and a two- or three- dimensional structure for the lower crust. Several conductive features can be distinguished: (i) a strong “ocean effect” at the southern most site, (ii) a zone of very high conductivity in the central part of the profile, and (iii) a conductor in the north that cannot be caused by the shallow Java sea. We discuss tentatively causes for these anomalies. The conductor in the central part of the profile is probably connected with volcanic or geothermal activity, while the anomaly in the north could be an expression of processes associated with an active fault zone.

  3. Impacted primary mandibular central incisors: case report.

    PubMed

    Darwish, Salwa M; Salama, Fouad S

    2002-01-01

    Impaction of primary teeth is very rare especially in the maxillary anterior teeth. A tooth that fails to erupt into a normal functional position by the time it normally should, is considered impacted. The purpose of this article is to present a case of a 2 year and 4-month-old male with an impacted primary mandibular central incisors. Clinical examination did not reveal systemic diseases or trauma in the facial region. Clinical and radiographic examinations are described. Treatment consisted of a period of observation for 6 months and the extraction of the impacted primary mandibular central incisors. Eight months after the surgery, the permanent central incisors were erupted in the proper position.

  4. Central venous obstruction in the thorax.

    PubMed

    Collin, G; Jones, R G; Willis, A P

    2015-06-01

    Central venous stenosis and occlusion can occur secondary to a spectrum of conditions ranging from aggressive malignancy to benign extrinsic anatomical compression in otherwise healthy individuals. Irrespective of aetiology, significant morbidity in the acute setting and long term can occur unless prompt accurate diagnosis and appropriate management is initiated, the radiologist being central to both. The present review will provide radiologists with a thorough illustration and explanation of the range of central venous conditions in the thorax (including deep vein thrombosis, thoracic outlet syndrome, haemodialysis, and malignancy related causes), the salient imaging findings and interventional management using case examples from the authors' practice. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  5. Hydrogels for central nervous system therapeutic strategies.

    PubMed

    Russo, Teresa; Tunesi, Marta; Giordano, Carmen; Gloria, Antonio; Ambrosio, Luigi

    2015-12-01

    The central nervous system shows a limited regenerative capacity, and injuries or diseases, such as those in the spinal, brain and retina, are a great problem since current therapies seem to be unable to achieve good results in terms of significant functional recovery. Different promising therapies have been suggested, the aim being to restore at least some of the lost functions. The current review deals with the use of hydrogels in developing advanced devices for central nervous system therapeutic strategies. Several approaches, involving cell-based therapy, delivery of bioactive molecules and nanoparticle-based drug delivery, will be first reviewed. Finally, some examples of injectable hydrogels for the delivery of bioactive molecules in central nervous system will be reported, and the key features as well as the basic principles in designing multifunctional devices will be described.

  6. Dry needling — peripheral and central considerations

    PubMed Central

    Dommerholt, Jan

    2011-01-01

    Dry needling is a common treatment technique in orthopedic manual physical therapy. Although various dry needling approaches exist, the more common and best supported approach targets myofascial trigger points. This article aims to place trigger point dry needling within the context of pain sciences. From a pain science perspective, trigger points are constant sources of peripheral nociceptive input leading to peripheral and central sensitization. Dry needling cannot only reverse some aspects of central sensitization, it reduces local and referred pain, improves range of motion and muscle activation pattern, and alters the chemical environment of trigger points. Trigger point dry needling should be based on a thorough understanding of the scientific background of trigger points, the differences and similarities between active and latent trigger points, motor adaptation, and central sensitize application. Several outcome studies are included, as well as comments on dry needling and acupuncture. PMID:23115475

  7. Thrombolytic therapy for central venous catheter occlusion

    PubMed Central

    Baskin, Jacquelyn L.; Reiss, Ulrike; Wilimas, Judith A.; Metzger, Monika L.; Ribeiro, Raul C.; Pui, Ching-Hon; Howard, Scott C.

    2012-01-01

    Background Long-term central venous catheters have improved the quality of care for patients with chronic illnesses, but are complicated by obstructions which can result in delay of treatment or catheter removal. Design and Methods This paper reviews thrombolytic treatment for catheter obstruction. Literature from Medline searches using the terms “central venous catheter”, “central venous access device” OR “central venous line” associated with the terms “obstruction”, “occlusion” OR “thrombolytic” was reviewed. Efficacy of thrombolytic therapy, central venous catheter clearance rates and time to clearance were assessed. Results Alteplase, one of the current therapies, clears 52% of obstructed catheters within 30 min with 86% overall clearance (after 2 doses, when necessary). However, newer medications may have higher efficacy or shorter time to clearance. Reteplase cleared 67–74% within 30–40 min and 95% of catheters overall. Occlusions were resolved in 70 and 83% of patients with one and 2 doses of tenecteplase, respectively. Recombinant urokinase cleared 60% of catheters at 30 min and 73% overall. Alfimeprase demonstrated rapid catheter clearance with resolution in 40% of subjects within 5 min, 60% within 30 min, and 80% within 2 h. Additionally, urokinase prophylaxis decreased the incidence of catheter occlusions from 16–68% in the control group to 4–23% in the treatment group; in some studies, rates of catheter infections were also decreased in the urokinase group. Conclusions Thrombolytic agents successfully clear central venous catheter occlusions in most cases. Newer agents may act more rapidly and effectively than currently utilized therapies, but randomized studies with direct comparisons of these agents are needed to determine optimal management for catheter obstruction. PMID:22180420

  8. HANFORD SITE CENTRAL PLATEAU CLEANUP COMPLETION STRATEGY

    SciTech Connect

    BERGMAN TB

    2011-01-14

    Cleanup of the Hanford Site is a complex and challenging undertaking. The U.S. Department of Energy (DOE) has developed a comprehensive vision for completing Hanford's cleanup mission including transition to post-cleanup activities. This vision includes 3 principle components of cleanup: the {approx}200 square miles ofland adjacent to the Columbia River, known as the River Corridor; the 75 square miles of land in the center of the Hanford Site, where the majority of the reprocessing and waste management activities have occurred, known as the Central Plateau; and the stored reprocessing wastes in the Central Plateau, the Tank Wastes. Cleanup of the River Corridor is well underway and is progressing towards completion of most cleanup actions by 2015. Tank waste cleanup is progressing on a longer schedule due to the complexity of the mission, with construction of the largest nuclear construction project in the United States, the Waste Treatment Plant, over 50% complete. With the progress on the River Corridor and Tank Waste, it is time to place increased emphasis on moving forward with cleanup of the Central Plateau. Cleanup of the Hanford Site has been proceeding under a framework defmed in the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement). In early 2009, the DOE, the State of Washington Department of Ecology, and the U.S. Environmental Protection Agency signed an Agreement in Principle in which the parties recognized the need to develop a more comprehensive strategy for cleanup of the Central Plateau. DOE agreed to develop a Central Plateau Cleanup Completion Strategy as a starting point for discussions. This DOE Strategy was the basis for negotiations between the Parties, discussions with the State of Oregon, the Hanford Advisory Board, and other Stakeholder groups (including open public meetings), and consultation with the Tribal Nations. The change packages to incorporate the Central Plateau Cleanup Completion Strategy were signed by

  9. 75 FR 14436 - Ameren Corporation, Illinois Power Company, Central Illinois Light Company, Central Illinois...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-25

    ... Energy Regulatory Commission Ameren Corporation, Illinois Power Company, Central Illinois Light Company, Central Illinois Public Service Company, Ameren Energy Resources Company, LLC, AmerenEnergy Resources Generating Company; Notice of Filing March 18, 2010. Take notice that on March 15, 2010, Ameren...

  10. Agreement Between Central Michigan University and Central Michigan University District of Michigan Association of Higher Education.

    ERIC Educational Resources Information Center

    Central Michigan Univ., Mount Pleasant.

    This document presents the agreement between the Central Michigan University (CMU) and Central Michigan University, District of Michigan Association of Higher Education. The agreement covers the purpose and intent, recognition, aid to other collective bargaining agents, deduction of district dues and initiation fees, special conferences, grievance…

  11. District Central Office Leadership as Teaching: How Central Office Administrators Support Principals' Development as Instructional Leaders

    ERIC Educational Resources Information Center

    Honig, Meredith I.

    2012-01-01

    Purpose: Research on educational leadership underscores the importance of principals operating as instructional leaders and intensive job-embedded supports for such work; this research also identifies central office staff as key support providers. However, it teaches little about what central office staff do when they provide such support and how…

  12. What Can We Learn from 15,000 Teachers in Central Europe and Central Asia?

    ERIC Educational Resources Information Center

    Temple, Charles

    2000-01-01

    Describes the "Reading and Writing for Critical Thinking Project" which has now sent more than 70 volunteer teacher educators into 20 countries across Central Europe and Central Asia to help teachers to try out methods that foster active learning and critical thinking. Discusses support for the project, teaching strategies introduced,…

  13. District Central Office Leadership as Teaching: How Central Office Administrators Support Principals' Development as Instructional Leaders

    ERIC Educational Resources Information Center

    Honig, Meredith I.

    2012-01-01

    Purpose: Research on educational leadership underscores the importance of principals operating as instructional leaders and intensive job-embedded supports for such work; this research also identifies central office staff as key support providers. However, it teaches little about what central office staff do when they provide such support and how…

  14. What Can We Learn from 15,000 Teachers in Central Europe and Central Asia?

    ERIC Educational Resources Information Center

    Temple, Charles

    2000-01-01

    Describes the "Reading and Writing for Critical Thinking Project" which has now sent more than 70 volunteer teacher educators into 20 countries across Central Europe and Central Asia to help teachers to try out methods that foster active learning and critical thinking. Discusses support for the project, teaching strategies introduced,…

  15. Flash Flooding Events in South Central Texas.

    DTIC Science & Technology

    1982-08-01

    I AD-ALI 977 AIR FORCE INST OF TECH WRIGHT-PATTERSON AFa OH F/G 4/2 FLASH FLOODING EVENTS IN SOUTH CENTRAL TEXAS. CU) N AU 82 T W UTLEY UNCLASSIFIED...COVERED Flash Flooding Events in South Central Texas THESIS/ESeAMAN S. PERFORMING ORG. REPORI NUMBER 7. AUTHOR(*) S. CONTRACT OR GRANT NUMBER(s) Tom...and to flash flooding events which occurred in 1981 they proved to be excellent predi’ctors. When compared to the 1981 National Weather Service

  16. Hydrological climate change projections for Central America

    NASA Astrophysics Data System (ADS)

    Hidalgo, Hugo G.; Amador, Jorge A.; Alfaro, Eric J.; Quesada, Beatriz

    2013-07-01

    Runoff climate change projections for the 21st century were calculated from a suite of 30 General Circulation Model (GCM) simulations for the A1B emission scenario in a 0.5° × 0.5° grid over Central America. The GCM data were downscaled using a version of the Bias Correction and Spatial Downscaling (BCSD) method and then used in the Variable Infiltration Capacity (VIC) macroscale hydrological model. The VIC model showed calibration skill in Honduras, Nicaragua, Costa Rica and Panama, but the results for some of the northern countries (Guatemala, El Salvador and Belize) and for the Caribbean coast of Central America was not satisfactory. Bias correction showed to remove effectively the biases in the GCMs. Results of the projected climate in the 2050-2099 period showed median significant reductions in precipitation (as much as 5-10%) and runoff (as much as 10-30%) in northern Central America. Therefore in this sub-region the prevalence of severe drought may increase significantly in the future under this emissions scenario. Northern Central America could warm as much as 3 °C during 2050-2099 and southern Central America could reach increases as much as 4 °C during the same period. The projected dry pattern over Central America is consistent with a southward displacement of the Intertropical Convergence Zone (ITCZ). In addition, downscaling of the NCEP/NCAR Reanalysis data from 1948 to 2012 and posterior run in VIC, for two locations in the northern and southern sub-regions of Central America, suggested that the annual runoff has been decreasing since ca. 1980, which is consistent with the sign of the runoff changes of the GCM projections. However, the Reanalysis 1980-2012 drying trends are generally much stronger than the corresponding GCM trends. Among the possible reasons for that discrepancy are model deficiencies, amplification of the trends due to constructive interference with natural modes of variability in the Reanalysis data, errors in the Reanalysis

  17. Anatomic considerations for central venous cannulation

    PubMed Central

    Bannon, Michael P; Heller, Stephanie F; Rivera, Mariela

    2011-01-01

    Central venous cannulation is a commonly performed procedure which facilitates resuscitation, nutritional support, and long-term vascular access. Mechanical complications most often occur during insertion and are intimately related to the anatomic relationship of the central veins. Working knowledge of surface and deep anatomy minimizes complications. Use of surface anatomic landmarks to orient the deep course of cannulating needle tracts appropriately comprises the crux of complication avoidance. The authors describe use of surface landmarks to facilitate safe placement of internal jugular, subclavian, and femoral venous catheters. The role of real-time sonography as a safety-enhancing adjunct is reviewed. PMID:22312225

  18. Qualification testing for a central station

    NASA Technical Reports Server (NTRS)

    Forrester, D. L.

    1983-01-01

    Qualification testing for a Central Station Photovoltaic (PV) Facility depends to a great extent on the system design, (fixed versus tracking), and the level of data acquisition/control which is incorporated into the system. The basic elements which require qualification tests include: dc power production/collection; tracker conversion systems; ac utility interface; system level control; and data acquisition/reporting. The qualification tests from the Lungo (ARCO) 1 MW Facility which were completed in January 1983 are discussed. The philosophy and many of the procedures are applicable to any central station PV facility.

  19. Church Orientations in Central and Eastern Europe

    NASA Astrophysics Data System (ADS)

    Laužikas, Rimvydas

    The objective of this case study is to discuss church orientation in Central and Eastern Europe. Due to its geographical situation, this region is a specific part of European cultural space: it is remote from the main cultural centers, it was the last to adopt Christianity, and it experienced intensive interactions with Byzantine culture. Therefore, we can assess church orientation in Central and Eastern Europe as a tradition affected by multicultural interactions and in which there is an interlacement of Catholicism from Western Europe, Byzantinism, local pagan faiths and, in part, the ideas of conception of geographical space of the Jews, Karaites, and Muslims.

  20. Central Calorimeter Thermal Gradient Module Connection Analysis

    SciTech Connect

    Rudland, D.L.; /Fermilab

    1987-08-07

    Two 20 kW condensing and one 10 kW steady state cooling coils will be used to cool and condense gaseous argon in the Central Calorimeter (CC) Cryostat. Since this cool down (300K to 90K) will inevitably cause shrinkage in the modules contained inside the cryostat, the connections between the modules have to be designed to withstand the increase in forces and moments induced by this contraction. This paper presents finite element analysis (ANSYS{reg_sign}) results to aid in the design or modification of the Central Calorimeter module connections.

  1. Hemodialysis catheter-associated central venous stenosis.

    PubMed

    Yevzlin, Alexander S

    2008-01-01

    The purpose of this review is to explore the pathophysiology, epidemiology, and interventional treatment of central vein stenosis (CVS) that may result from central vein catheter (CVC) placement. The precise mechanism of CVC-associated CVS remains largely undefined, though anatomic considerations appear to play a prominent pathologic role. The impact of CVC-associated CVS on arteriovenous fistula outcomes is reviewed. The percutaneous treatment of CVS, observation, angioplasty, or angioplasty with stent placement is reviewed, along with potential surgical treatment options. As the treatment outcomes of CVC-associated CVS have been disappointing, catheter avoidance remains the best strategy.

  2. Central pattern generators and interphyletic awareness.

    PubMed

    Stein, P S

    1999-01-01

    Our understandings of how neuronal networks organized as central pattern generators generate motor behavior have greatly increased in the last 40 years. In the 60s, many investigators studying invertebrate motor behaviors were not aware of the work of those studying vertebrate motor behaviors, and vice versa. In the 70s, key conferences provided venues for important interactions among investigators working on preparations in different species. These interactions, termed interphyletic awareness, continued in the 80s and 90s at major conferences and played important roles in the development of our understandings of central pattern generators for motor behavior in these decades.

  3. Peripheral and central mechanisms of stress resilience

    PubMed Central

    Pfau, Madeline L.; Russo, Scott J.

    2014-01-01

    Viable new treatments for depression and anxiety have been slow to emerge, likely owing to the complex and incompletely understood etiology of these disorders. A budding area of research with great therapeutic promise involves the study of resilience, the adaptive maintenance of normal physiology and behavior despite exposure to marked psychological stress. This phenomenon, documented in both humans and animal models, involves coordinated biological mechanisms in numerous bodily systems, both peripheral and central. In this review, we provide an overview of resilience mechanisms throughout the body, discussing current research in animal models investigating the roles of the neuroendocrine, immune, and central nervous systems in behavioral resilience to stress. PMID:25506605

  4. On central-difference and upwind schemes

    NASA Technical Reports Server (NTRS)

    Swanson, R. C.; Turkel, Eli

    1990-01-01

    A class of numerical dissipation models for central-difference schemes constructed with second- and fourth-difference terms is considered. The notion of matrix dissipation associated with upwind schemes is used to establish improved shock capturing capability for these models. In addition, conditions are given that guarantee that such dissipation models produce a Total Variation Diminishing (TVD) scheme. Appropriate switches for this type of model to ensure satisfaction of the TVD property are presented. Significant improvements in the accuracy of a central-difference scheme are demonstrated by computing both inviscid and viscous transonic airfoil flows.

  5. Hydrology of Central Florida Lakes - A Primer

    USGS Publications Warehouse

    Schiffer, Donna M.

    1998-01-01

    INTRODUCTION Lakes are among the most valued natural resources of central Florida. The landscape of central Florida is riddled with lakeswhen viewed from the air, it almost seems there is more water than land. Florida has more naturally formed lakes than other southeastern States, where many lakes are created by building dams across streams. The abundance of lakes on the Florida peninsula is a result of the geology and geologic history of the State. An estimated 7,800 lakes in Florida are greater than 1 acre in surface area. Of these, 35 percent are located in just four counties (fig. 1): Lake, Orange, Osceola, and Polk (Hughes, 1974b). Lakes add to the aesthetic and commercial value of the area and are used by many residents and visitors for fishing, boating, swimming, and other types of outdoor recreation. Lakes also are used for other purposes such as irrigation, flood control, water supply, and navigation. Residents and visitors commonly ask questions such as Whyare there so many lakes here?, Why is my lake drying up (or flooding)?, or Is my lake spring-fed? These questions indicate that the basic hydrology of lakes and the interaction of lakes with ground water and surface water are not well understood by the general population. Because of the importance of lakes to residents of central Florida and the many questions and misconceptions about lakes, this primer was prepared by the U.S. Geological Survey (USGS) in cooperation with the St. Johns River Water Management District and the South Florida Water Management District. The USGS has been collecting hydrologic data in central Florida since the 1920s, obtaining valuable information that has been used to better understand the hydrology of the water resources of central Florida, including lakes. In addition to data collection, as of 1994, the USGS had published 66 reports and maps on central Florida lakes (Garcia and Hoy, 1995). The main purpose of this primer is to describe the hydrology of lakes in central

  6. Central and non-central networks, cognition, clinical symptoms, and polygenic risk scores in schizophrenia.

    PubMed

    Alloza, Clara; Bastin, Mark E; Cox, Simon R; Gibson, Jude; Duff, Barbara; Semple, Scott I; Whalley, Heather C; Lawrie, Stephen M

    2017-09-07

    Schizophrenia is a complex disorder that may be the result of aberrant connections between specific brain regions rather than focal brain abnormalities. Here, we investigate the relationships between brain structural connectivity as described by network analysis, intelligence, symptoms, and polygenic risk scores (PGRS) for schizophrenia in a group of patients with schizophrenia and a group of healthy controls. Recently, researchers have shown an interest in the role of high centrality networks in the disorder. However, the importance of non-central networks still remains unclear. Thus, we specifically examined network-averaged fractional anisotropy (mean edge weight) in central and non-central subnetworks. Connections with the highest betweenness centrality within the average network (>75% of centrality values) were selected to represent the central subnetwork. The remaining connections were assigned to the non-central subnetwork. Additionally, we calculated graph theory measures from the average network (connections that occur in at least 2/3 of participants). Density, strength, global efficiency, and clustering coefficient were significantly lower in patients compared with healthy controls for the average network (pFDR  < 0.05). All metrics across networks were significantly associated with intelligence (pFDR  < 0.05). There was a tendency towards significance for a correlation between intelligence and PGRS for schizophrenia (r = -0.508, p = 0.052) that was significantly mediated by central and non-central mean edge weight and every graph metric from the average network. These results are consistent with the hypothesis that intelligence deficits are associated with a genetic risk for schizophrenia, which is mediated via the disruption of distributed brain networks. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  7. Central Mississippi River Basin LTAR site overview

    USDA-ARS?s Scientific Manuscript database

    The Central Mississippi River Basin (CMRB) member of the Long-Term Agro-ecosystem Research (LTAR) network is representative of the southern Corn Belt, where subsoil clay content makes tile drainage challenging and make surface runoff and associated erosion problematic. Substantial research infrastru...

  8. Universities and Knowledge Production in Central Europe

    ERIC Educational Resources Information Center

    Kwiek, Marek

    2012-01-01

    The article discusses an East/West divide in Europe in university knowledge production. It argues that the communist and post-communist legacies in the four major Central European economies studied (Poland, Hungary, the Czech Republic and the Slovak Republic) matter substantially for educational and research systems. The differences in university…

  9. Central Asia: A New Great Game?

    DTIC Science & Technology

    2007-11-02

    southward from civil war, or of revolutionary slogans hitting a chord with Iran’s own ethnic minorities, can only be met by economic investment and reliance...concern, both public and private, over the impact of radiation drifting into Kazakhstan has also been quite vocal .108 Chinese concerns about Central

  10. The Centrality of Engagement in Higher Education

    ERIC Educational Resources Information Center

    Fitzgerald, Hiram E.; Bruns, Karen; Sonka, Steven T.; Furco, Andrew; Swanson, Louis

    2012-01-01

    The centrality of engagement is critical to the success of higher education in the future. Engagement is essential to most effectively achieving the overall purpose of the university, which is focused on the knowledge enterprise. Today's engagement is scholarly, is an aspect of learning and discovery, and enhances society and higher education.…

  11. English Language Teaching Profile: Central African Republic.

    ERIC Educational Resources Information Center

    British Council, London (England). English-Teaching Information Centre.

    This profile in outline form of the English language teaching situation in the Central African Republic discusses the role of English and English within the educational system. While French is the official language and Sango is the national language, English is taught in all secondary schools, is used as the medium of instruction in the University…

  12. Prescribed burning in the North Central States.

    Treesearch

    Linda R. Donoghue; Von J. Johnson

    1975-01-01

    Describes 5 years of prescribed burning in the North Central States from 1968 through 1972. Provides information concerning participating agencies, burned-acreage, purpose-of-burn, fuels, and weather. Also examines other aspects such as ignition and burning techniques, hours-to-complete, time of fire start, and cost-per-acre.

  13. Equity and Difference in Centralized Policy

    ERIC Educational Resources Information Center

    Macedo, Elizabeth

    2013-01-01

    The paper focuses on the promise of equity that underlies centralized evaluation policies and its relation to difference, or in other words to the singularity of the subject. I defend that without taking the issue of difference into consideration, there is no education, and that the unique subject is what is aspired by education. The analyses rely…

  14. Forest statistics for Central Mississippi counties - 1987

    Treesearch

    John F. Kelly; F. Dee Hines

    1987-01-01

    The 1987 survey of the 14 counties in the Central Mississippi unit indicated the following changes since the previous survey in 1977:Timberland area, now covering 4,097.0 thousand acres, has increased 6 percent.Forest industry-owned timberland increased 112.5 thousand acres or 13 percent.Pine forest types...

  15. Forest statistics for Central Tennessee counties - 1989

    Treesearch

    Dennis M. May; John S. Vissage

    1989-01-01

    The 1989 survey of the Central Unit of Tennessee revealed the following:Timberland now covers 2,416.3 thousand acres, an increase of 14 percent since 1980.Ninety-five percent of the unit’s timberland is privately owned.Cedar and mixed cedar-hardwood stands occupy 456.1 thousand acres of timberland....

  16. 20 CFR 346.1 - Central register.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Central register. 346.1 Section 346.1 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT... employees with at least one year of service who have declared their current availability for rail...

  17. SPIRONOLACTONE FOR NONRESOLVING CENTRAL SEROUS CHORIORETINOPATHY

    PubMed Central

    Bousquet, Elodie; Beydoun, Talal; Rothschild, Pierre-Raphaël; Bergin, Ciara; Zhao, Min; Batista, Rui; Brandely, Marie-Laure; Couraud, Benedicte; Farman, Nicolette; Gaudric, Alain; Chast, François

    2015-01-01

    Purpose: To evaluate the effect of spironolactone, a mineralocorticoid receptor antagonist, for nonresolving central serous chorioretinopathy. Methods: This is a prospective, randomized, double-blinded, placebo-controlled crossover study. Sixteen eyes of 16 patients with central serous chorioretinopathy and persistent subretinal fluid (SRF) for at least 3 months were enrolled. Patients were randomized to receive either spironolactone 50 mg or placebo once a day for 30 days, followed by a washout period of 1 week and then crossed over to either placebo or spironolactone for another 30 days. The primary outcome measure was the changes from baseline in SRF thickness at the apex of the serous retinal detachment. Secondary outcomes included subfoveal choroidal thickness and the ETDRS best-corrected visual acuity. Results: The mean duration of central serous chorioretinopathy before enrollment in study eyes was 10 ± 16.9 months. Crossover data analysis showed a statistically significant reduction in SRF in spironolactone treated eyes as compared with the same eyes under placebo (P = 0.04). Secondary analysis on the first period (Day 0–Day 30) showed a significant reduction in subfoveal choroidal thickness in treated eyes as compared with placebo (P = 0.02). No significant changes were observed in the best-corrected visual acuity. There were no complications related to treatment observed. Conclusion: In eyes with persistent SRF due to central serous chorioretinopathy, spironolactone significantly reduced both the SRF and the subfoveal choroidal thickness as compared with placebo. PMID:26017871

  18. Forest statistics for Central Tennessee counties

    Treesearch

    Renewable Resources Evaluation Research Work Unit

    1981-01-01

    These tables were derived from data obtained during a 1980 inventory of 23 counties comprising the Central Unit of Tennessee (fig. 1). The data on forest acreage and timber volume were secured by a systematic sampling method involving a forest-non-forest classification on aerial photographs and on-the-ground measurements of trees at sample locations. The sample...

  19. Evolution in a centralized transfusion service.

    PubMed

    AuBuchon, James P; Linauts, Sandra; Vaughan, Mimi; Wagner, Jeffrey; Delaney, Meghan; Nester, Theresa

    2011-12-01

    The metropolitan Seattle area has utilized a centralized transfusion service model throughout the modern era of blood banking. This approach has used four laboratories to serve over 20 hospitals and clinics, providing greater capabilities for all at a lower consumption of resources than if each depended on its own laboratory and staff for these functions. In addition, this centralized model has facilitated wider use of the medical capabilities of the blood center's physicians, and a county-wide network of transfusion safety officers is now being developed to increase the impact of the blood center's transfusion expertise at the patient's bedside. Medical expectations and traffic have led the blood center to evolve the centralized model to include on-site laboratories at facilities with complex transfusion requirements (e.g., a children's hospital) and to implement in all the others a system of remote allocation. This new capability places a refrigerator stocked with uncrossmatched units in the hospital but retains control over the dispensing of these through the blood center's computer system; the correct unit can be electronically cross-matched and released on demand, obviating the need for transportation to the hospital and thus speeding transfusion. This centralized transfusion model has withstood the test of time and continues to evolve to meet new situations and ensure optimal patient care.

  20. Proceedings, 16th central hardwood forest conference

    Treesearch

    Douglass F. Jacobs; Charles H., eds. Michler

    2008-01-01

    Proceedings of the 16th Central Hardwood Forest Conference held April 8-9, 2008, in West Lafayette, IN. Includes 64 papers pertaining to forest regeneration and propagation, forest products, ecology and forest dynamics, human dimensions and economics, forest biometrics and modeling, silviculture and genetics, forest health and protection, and soil and mineral nutrition...

  1. Procedures of Operation at Cranbrook Central Library.

    ERIC Educational Resources Information Center

    Cranbrook Institutions, Bloomfield Hills, MI. Central Library.

    This manual outlines the ordering, cataloging and classification, and processing procedures for books, periodicals, government documents, and non-book materials for a central library serving three schools--a co-ed elementary school and separate junior-senior high schools for boys and girls--and four special libraries--a fine and rare books…

  2. Central New York Climate Change Innovation Program

    EPA Pesticide Factsheets

    This page is about the Central New York Regional Planning and Development Board's EPA CSC grant. EPA’s CSC Program helps local governments and tribal nations pilot innovative, cost-effective and replicable community-based greenhouse gas reduction projects.

  3. Bruxism is mainly regulated centrally, not peripherally.

    PubMed

    Lobbezoo, F; Naeije, M

    2001-12-01

    Bruxism is a controversial phenomenon. Both its definition and the diagnostic procedure contribute to the fact that the literature about the aetiology of this disorder is difficult to interpret. There is, however, consensus about the multifactorial nature of the aetiology. Besides peripheral (morphological) factors, central (pathophysiological and psychological) factors can be distinguished. In the past, morphological factors, like occlusal discrepancies and the anatomy of the bony structures of the orofacial region, have been considered the main causative factors for bruxism. Nowadays, these factors play only a small role, if any. Recent focus is more on the pathophysiological factors. For example, bruxism has been suggested to be part of a sleep arousal response. In addition, bruxism appears to be modulated by various neurotransmitters in the central nervous system. More specifically, disturbances in the central dopaminergic system have been linked to bruxism. Further, factors like smoking, alcohol, drugs, diseases and trauma may be involved in the bruxism aetiology. Psychological factors like stress and personality are frequently mentioned in relation to bruxism as well. However, research to these factors comes to equivocal results and needs further attention. Taken all evidence together, bruxism appears to be mainly regulated centrally, not peripherally.

  4. Central Virginia Community College 1999 Fact Book.

    ERIC Educational Resources Information Center

    Hicks, Geoffrey

    The Fact Book is an annual publication of the Office of Research, Assessment and Planning at Central Virginia Community College (CVCC). It includes data and trends from 1994-1998 and is divided into six parts: (1) "The College" includes information on the College Board, institutional history, facilities, mission and goals, revenues and…

  5. Proceedings, 10th Central Hardwood Forest Conference

    Treesearch

    Kurt W. Gottschalk; Sandra L.C., eds. Fosbroke

    1995-01-01

    Two invited papers, 57 volunteer papers, and 22 volunteer poster summaries presented at the 10th Central Hardwood Forest Conference. Presentation topics included economics, forest amenities, harvesting, logging safety, utilization, physiology, genetics, ecology, regeneration, silviculture, protection, management, hydrology, soils, nutrient cycling, and hardwood markets...

  6. Intracranial calcification in central diabetes insipidus.

    PubMed

    Al-Kandari, Salwa Ramadan; Pandey, Tarun; Badawi, Mona H

    2008-01-01

    Intracranial calcification is a known but extremely rare complication of diabetes insipidus. To date, only 16 patients have been reported and all had the peripheral (nephrogenic) type of diabetes insipidus. We report a child with intracranial calcification complicating central diabetes insipidus. We also report a child with nephrogenic diabetes insipidus, and compare the patterns of intracranial calcification.

  7. Central State University: Phase I Report

    ERIC Educational Resources Information Center

    Ohio Board of Regents, 2012

    2012-01-01

    In December of 2011, a team of eight consultants authored a report to the Ohio Board of Regents and Central State University titled "Accentuating Strengths/Accelerating Progress (AS/AP)." AS/AP provided a road map for the administration, faculty, and staff of CSU to achieve the excellence it has sought under the leadership of President…

  8. Central Park East: An Alternative Story.

    ERIC Educational Resources Information Center

    Meier, Deborah

    1987-01-01

    Central Park East school was founded in 1974 in Harlem (NY) as an alternative elementary school within the public inner city school system. In 1984 it had expanded into three elementary alternative schools and added a fourth secondary school. It is considered a progressive school following in the tradition of New York city's private schools. (MD)

  9. Characterization of high elevation central Appalachian wetlands

    Treesearch

    K.E. Francl; W.M. Ford; S.B. and Castleberry

    2004-01-01

    We characterized 20 high elevation wetlands in the central Appalachian Mountains in West Virginia and Maryland, in terms of vegetation, soils, hydrology, and geology. Plant species were distributed along soil chemical (pH, conductivity) and physical (organic matter depth) gradients across sites. Topography and geology appear to explain differences among these wetlands...

  10. Forest statistics for Central Florida - 1995

    Treesearch

    Mark J. Brown

    1996-01-01

    This report highlights the principal findings of the seventh forest survey of Central Florida. Field work began in February 1995 and was completed in May 1995. Six previous surveys, completed in 1936, 1949, 1959, 1970, 1960, and 1988 provide statistics for measuring changes and trends over the past 59 years. This report primarily emphasizes the changes and trends since...

  11. Forest statistics for Central Georgia, 1997

    Treesearch

    Michael T. Thompson

    1998-01-01

    This report highlights the principal findings of the seventh forest survey of Central Georgia. Field work began in November 1996 and was completed in August 1997. Six previous surveys, completed in 1936, 1952, 1961, 1972, 1982, and 1989 provide statistics for measuring changes and trends over the past 61 years. This report primarily emphasizes the changes and trends...

  12. Forest statistics for North Central Georgia, 1998

    Treesearch

    Michael T. Thompson

    1998-01-01

    This report highlights the principal findings of the seventh forest survey of North Central Georgia. Field work began in June 1997 and was completed in November 1997. Six previous surveys, completed in 1936, 1953, 196 1, 1972, 1983, and 1989 provide statistics for measuring changes and trends over the past 6 1 years. This report primarily emphasizes the changes and...

  13. The Physics of Central Heating of Houses

    ERIC Educational Resources Information Center

    Cowking, A.; And Others

    1978-01-01

    Explains the function of a central heating system and calculates the total heat energy required to heat a house. Estimates annual heat requirement and amount of fuel needed. Gives detailed calculation of heat required for a particular house as an example. (G A)

  14. Recovery of central Appalachian forested watershed

    Treesearch

    Mary Beth Adams; James N. Kochendenfer [sic

    2014-01-01

    The Fernow Experimental Forest (FEF) was established to conduct research in forest and watershed management in the central Appalachians. The 1868-ha FEF, located south of Parsons, West Virginia, is administered by the Northern Research Station of the USDA Forest Service and provides a valuable point of comparison with the Coweeta Hydrologic Laboratory (CHL), located in...

  15. Peripherally inserted central catheters. Intravenous Nurses Society.

    PubMed

    1997-01-01

    The Intravenous Nurses Society (INS) recognizes the need for uniform terminology for peripherally inserted central catheters (PICCs) to encourage standardization for indications, care, and maintenance strategies for these devices. It also recognizes the need for recommendations regarding the choice, use, management, and discontinuation of PICCs to promote positive patient outcomes and enhance patient comfort, safety, and satisfaction.

  16. Forest habitat types of central Idaho

    Treesearch

    Robert Steele; Robert D. Pfister; Russell A. Ryker; Jay A. Kittams

    1981-01-01

    A land-classification system based upon potential natural vegetation is presented for the forests of central Idaho. It is based on reconnaissance sampling of about 800 stands. A hierarchical taxonomic classification of forest sites was developed using the habitat type concept. A total of eight climax series, 64 habitat types, and 55 additional phases of habitat types...

  17. Forest statistics for west central Oregon.

    Treesearch

    John W. Hazard; Melvin E. Metcalf

    1965-01-01

    This publication summarizes the results of the latest reinventory of four counties centrally located in western Oregon: Benton, Lane, Lincoln, and Linn. This block of four counties is one of 10 such blocks set up in the States of Oregon and Washington by the Forest Survey to facilitate orderly reinventories of the timber resources. Each block will be reinventoried at...

  18. Gravimetric maps of the Central African Republic

    NASA Technical Reports Server (NTRS)

    Albouy, J.; Godivier, R. (Principal Investigator)

    1982-01-01

    Gravimetric maps of the Central African Republic are described including a map of Bouguer anomalies at 1/1,000,000 in two sections (eastern sheet, western sheet) and a map, in color, of Bouguer anomalies at 1/2,000,000. Instrumentation, data acquisition, calibration, and data correction procedures are discussed.

  19. Central carbon metabolism of Leishmania parasites.

    PubMed

    Saunders, Eleanor C; DE Souza, David P; Naderer, Thomas; Sernee, Marijke F; Ralton, Julie E; Doyle, Maria A; Macrae, James I; Chambers, Jenny L; Heng, Joanne; Nahid, Amsha; Likic, Vladimir A; McConville, Malcolm J

    2010-08-01

    Leishmania spp. are sandfly-transmitted protozoa parasites that cause a spectrum of diseases in humans. Many enzymes involved in Leishmania central carbon metabolism differ from their equivalents in the mammalian host and are potential drug targets. In this review we summarize recent advances in our understanding of Leishmania central carbon metabolism, focusing on pathways of carbon utilization that are required for growth and pathogenesis in the mammalian host. While Leishmania central carbon metabolism shares many features in common with other pathogenic trypanosomatids, significant differences are also apparent. Leishmania parasites are also unusual in constitutively expressing most core metabolic pathways throughout their life cycle, a feature that may allow these parasites to exploit a range of different carbon sources (primarily sugars and amino acids) rapidly in both the insect vector and vertebrate host. Indeed, recent gene deletion studies suggest that mammal-infective stages are dependent on multiple carbon sources in vivo. The application of metabolomic approaches, outlined here, are likely to be important in defining aspects of central carbon metabolism that are essential at different stages of mammalian host infection.

  20. Forest statistics for Central Georgia, 1972

    Treesearch

    Robert A. Cathey

    1971-01-01

    Annual growth exceeded removals in this 43-county area by 219 million cubic feet, or 73 percent. Southern yellow pines account for about 61 percent of this surplus growth. The average annual growth rate for Central Georgia is 68 cubic feet per acre of-commercial forest land, substantially higher than that found in either Southeast or Southwest Georgia. The area of...

  1. Forest statistics for North Central Georgia, 1989

    Treesearch

    Tony G. Johnson

    1989-01-01

    This report highlights the principal findings of the sixth forest survey in North Central Georgia. Field work began in February 1989 and was completed in April 1989. Five previous surveys, completed in 1936, 1953, 1961, 1972, and 1983, provide statistics for measuring changes and trends over the past 53 years. The primary emphasis in this report is on the changes and...

  2. Central Computational Facility CCF communications subsystem options

    NASA Technical Reports Server (NTRS)

    Hennigan, K. B.

    1979-01-01

    A MITRE study which investigated the communication options available to support both the remaining Central Computational Facility (CCF) computer systems and the proposed U1108 replacements is presented. The facilities utilized to link the remote user terminals with the CCF were analyzed and guidelines to provide more efficient communications were established.

  3. B-52 Aircraft on the Central Front

    DTIC Science & Technology

    1989-03-21

    57-58. 12. Gen. Leopold Chalupa , German Army, "Controlling Tactical Air and Ground Forces Within the Central European Command," Signal, October 1987...Conventional Warfare." Strategic Review, Vol. XVI, No. 2, Spring 1988, pp. 23-32. 10. Chalupa , Leopold, Gen., German Army. "Controlling Tactical Air

  4. Oak Regeneration Guidelines for the Central Appalachians

    Treesearch

    Kim C. Steiner; James C. Finley; Peter J. Gould; Songlin Fei; Marc McDill

    2008-01-01

    This article presents the first explicit guidelines for regenerating oaks in the central Appalachians. The objectives of this paper are (1) to describe the research foundation on which the guidelines are based and (2) to provide users with the instructions, data collection forms, supplementary tables, and decision charts needed to apply the guidelines in the field. The...

  5. The Centrality of Engagement in Higher Education

    ERIC Educational Resources Information Center

    Fitzgerald, Hiram E.; Bruns, Karen; Sonka, Steven T.; Furco, Andrew; Swanson, Louis

    2016-01-01

    The centrality of engagement is critical to the success of higher education in the future. Engagement is essential to most effectively achieving the overall purpose of the university, which is focused on the knowledge enterprise. Today's engagement is scholarly, is an aspect of learning and discovery, and enhances society and higher education.…

  6. Eye Movement Correlates of Acquired Central Dyslexia

    ERIC Educational Resources Information Center

    Schattka, Kerstin I.; Radach, Ralph; Huber, Walter

    2010-01-01

    Based on recent progress in theory and measurement techniques, the analysis of eye movements has become one of the major methodological tools in experimental reading research. Our work uses this approach to advance the understanding of impaired information processing in acquired central dyslexia of stroke patients with aphasia. Up to now there has…

  7. Gabapentin inhibits central sensitization during migraine.

    PubMed

    Zhang, Yanbo; Shao, Guo; Zhang, Wei; Li, Sijie; Niu, Jingzhong; Hu, Dongmei; Yang, Mingfeng; Ji, Xunming

    2013-11-15

    Peripheral and central sensitizations are phenomena that occur during migraine. The role of pentin, a migraine preventive drug, on central sensitization remains unclear. In this study, a rat model of migraine was established by electrical stimulation of the trigeminal ganglion, and the an-imals were given intragastric gabapentin. Changes in amino acid content in the cerebrospinal fluid and protein kinase C membrane translocation in the spinal trigeminal nucleus were examined to clarify the mechanisms underlying the efficacy of gabapentin in the treatment of central sensitization during migraine. Electrophysiology, liquid chromatography-mass spectrometry and western blot analysis results revealed that gabapentin reduces neuronal excitability in the spinal nucleus in the trigeminal nerve, decreases excitatory amino acid content and inhibits the activation of protein ki-nase C. This provides evidence that excitatory amino acids and protein kinase C are involved in the formation and maintenance of central sensitization during migraine. Gabapentin inhibits migraine by reducing excitatory amino acid content in the cerebrospinal fluid and inhibiting protein kinase C ac-tivation.

  8. Central cornea involvement in Terrien's degeneration.

    PubMed

    Nirankari, V S; Kelman, S E; Richards, R D

    1983-03-01

    A 15-year-old female showed classical signs of Terrien's corneal degeneration including peripheral corneal thinning, vascularization, lipid deposition, and ectasia. She also showed episodes of conjunctival inflammation and perforation following minor trauma, all in the presence of an intact epithelium. She also showed progressive central corneal thinning and opacification, features not reported in the literature in the last 30 years.

  9. [Central effects of ORL1 receptor ligands].

    PubMed

    Maslov, L N; Lishmanov, Iu B; Calo, G; Ma, L

    2003-01-01

    It has been discussed literature data on molecular structure of ORL1 receptor and its interaction with intracellular signal systems and neurotransmitters. Data on chemical structure of ORL1 receptor ligands and their central effects (nociception, locomotion, feeding, cognition) are presented.

  10. Central Auditory Processing Disorders: Mostly Management.

    ERIC Educational Resources Information Center

    Masters, M. Gay; Stecker, Nancy A.; Katz, Jack

    This book offers the latest available information on central auditory processing disorders (CAPDs) drawn from a State University of New York at Buffalo conference on CAPDs in September of 1996. It is divided into three parts: introduction, management approaches, and specific methods and populations. Chapters include: (1) "Overview and Update…

  11. Best Minds Sought for Central Office, Startups

    ERIC Educational Resources Information Center

    Maxwell, Lesli A.

    2009-01-01

    The central office isn't being overlooked in the movement to find and develop top talent for school districts. Although ways to recruit, groom, and keep top teachers and strong principals tend to dominate discussions of "human capital" needs in education, a handful of nonprofit organizations and foundations also see providing smart managers as…

  12. 13th Central Hardwoods Forest Conference

    Treesearch

    J.W. Van Sambeek; Jeffrey O. Dawson; Felix Jr Ponder; Edward F. Loewenstein; James S. Fralish

    2003-01-01

    This conference was the 13th in a series of biennial meetings that have been hosted by numerous universities and research stations of the USDA Forest Service in the Central Hardwood forest region in the eastern United States. The purpose of the Conference has remained the same since it's inception -- that is to provide a forum for the formal and informal exchange...

  13. 12th Central Hardwood Forest Conference

    Treesearch

    Jeffrey W. Stringer; David L. Loftis; Michael Lacki; Thomas Barnes; Robert A. Muller

    1999-01-01

    There were 32 oral presentations, 11 abstracts, and 22 poster presentations presented at the 12th Central Hardwood Forest Conference. Presentation topics included wildlife management, nutrient dynamics, stand structure, reforestation/reclamation, timber harvesting, modeling and inventory, silviculture, disturbance effects, and genetics/tree improvement.

  14. Central African Security: Conflict in the Congo

    DTIC Science & Technology

    2002-01-01

    Alliances mouvantes et conflits extraterritoriaux en Afrique Centrale. Paris: L’Hamarttan. Jean-Claude Willame, Banyarwanda et Banyamulenge: Violence...ethnique et gestion de l’identitaire au Kivu. Paris; L’Harmattan, 1997. Crawford Young, “Zaire: The Anatomy of a Failed State,” in David Birmingham & Phyllis

  15. Forest resources of west central Alabama

    Treesearch

    A.R. Spillers

    1940-01-01

    Lying west of Birmingham and north of Demopolis, West Central Alabama (Forest survey Unit Alabama No. 4) includes almost 4.5 million acres within the following 9 counties: Bibb, Fayette, Greene, Hale, Lamar, Marion, Perry, Pickens, and Tuscaloosa (map, fig. 1). This distinctly rural area includes only one incorporated city or town with a population of 2,500 people or...

  16. Stand hazard rating for central Idaho forests

    Treesearch

    Robert Steele; Ralph E. Williams; Julie C. Weatherby; Elizabeth D. Reinhardt; James T. Hoffman; R. W. Thier

    1996-01-01

    Growing concern over sustainability of central ldaho forests has created a need to assess the health of forest stands on a relative basis. A stand hazard rating was developed as a composite of 11 individual ratings to compare the health hazards of different stands. The composite rating includes Douglas-fir beetle, mountain pine beetle, western pine beetle, spruce...

  17. Computers in Central Government Ten Years Ahead.

    ERIC Educational Resources Information Center

    Her Majestys Stationery Office, London (England).

    A consultant team made an independent assessment of future prospects for the field of computer use in the central government of Great Britain. They first assessed the level of use of computers at the present time in all governmental agencies. They then forecast the future computer applications which developing technology will permit. They…

  18. Eye Movement Correlates of Acquired Central Dyslexia

    ERIC Educational Resources Information Center

    Schattka, Kerstin I.; Radach, Ralph; Huber, Walter

    2010-01-01

    Based on recent progress in theory and measurement techniques, the analysis of eye movements has become one of the major methodological tools in experimental reading research. Our work uses this approach to advance the understanding of impaired information processing in acquired central dyslexia of stroke patients with aphasia. Up to now there has…

  19. English Language Assessment in Central America.

    ERIC Educational Resources Information Center

    Crandall, JoAnn; And Others

    This document, the final report of a project assessing the general status of English language training (ELT) in Central America, includes an overview of the process, general recommendations, and country-specific information and recommendations for training and policy development. The purpose was to assess the potential effects of the ELT situation…

  20. Timber resource statistics for central Oregon.

    Treesearch

    John M. Berger

    1968-01-01

    This publication summarizes the results of the third inventory of the timber resources of nine counties in central Oregon: Crook, Deschutes, Gilliam, Jefferson, Klamath, Lake, Sherman, Wasco, and Wheeler. This block of nine counties is one of 10 such blocks set up in the States of Oregon and Washington by the Forest Survey to facilitate orderly reinventories of the...