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Sample records for beneath central america

  1. Frequency Dependant P Wave Structure of D" Beneath Central America Imaged by Kirchhoff Migration

    Science.gov (United States)

    Hutko, A. R.; Lay, T.; Revenaugh, J.

    2006-12-01

    We use thousands of seismograms from South and Central American earthquakes recorded by western North American seismic networks to image the lowermost mantle beneath Central America using a 3D Kirchhoff migration scheme. P wave studies of the deep mantle often rely on some form of stacking of many records in order to enhance the signal-to-noise ratio of weak phases generated by deep structure, such as reflections off of the D" discontinuity. These methods, however, often assume one-dimensional structure, which is at odds with the evidence for significant heterogeneity. Kirchhoff migration is a three-dimensional stacking method that allows interactions with structure off of the source-receiver plane, thus imaging a much larger volume and avoiding false projections of scattered arrivals onto specular reflectors. The D" discontinuity beneath Central America has been readily observed in S wave studies and may be the result of the shear wave velocity increase associated with the recently discovered perovskite to post-perovskite phase transition. This phase transition is expected to have weaker effects on P wave velocities than on S wave velocities and the sharpness of this transition is unknown. We observe structures consistent with a discontinuity about 200 km above the core-mantle boundary (CMB). The fact that this is seen at all in short period data suggests that its boundary must be less than 10 to 20 km thick, while observation with broadband data exclude the possibility of it being a thin layer or lamella. Whether the discontinuity is co-located for both P and S waves is difficult to resolve given uncertainties in the long-scale velocity heterogeneity. In addition, both broadband and short period P wave data sets reveal a sharp out-of-plane scatterer, which may be located close to the CMB. The short period data also indicate reflectivity about 400 km above the CMB, well above the aforementioned D" discontinuity, and similar reflectivity is observed under the

  2. The Lowermost Mantle Beneath Central America Imaged by Kirchhoff Migration of Scatterers and Reflectors

    Science.gov (United States)

    Hutko, A.; Lay, T.; Revenaugh, J.

    2007-05-01

    We use tens of thousands of seismograms from South and Central American earthquakes recorded by western North American seismic networks to image the lowermost mantle beneath Central America using a 3D Kirchhoff migration method. P wave studies of the deep mantle often rely on some form of stacking of many records in order to enhance the signal-to-noise ratio of weak phases generated by deep structure, such as reflections off of the D" discontinuity. These methods, however, often assume one-dimensional structure, which is at odds with the evidence for significant heterogeneity. Kirchhoff migration is a three-dimensional stacking method that allows interactions with structure outside of the source-receiver plane, thus illuminating a much larger volume. The D" discontinuity beneath Central America has been readily observed in S wave studies and may be the result of the shear wave velocity increase associated with the recently discovered perovskite to post-perovskite phase transition. This phase transition is expected to have weaker effects on P wave velocities than on S wave velocities and the sharpness of this transition is unknown. Using data at post-critical distances, we observe structures consistent with a P velocity discontinuity about 200 km above the core-mantle boundary (CMB). Observing this using short period data suggests that the boundary must be less than a few 10s of km thick, while observation with lower frequency broadband data exclude the possibility of it being a thin layer. Whether this discontinuity is co-located for both P and S waves is difficult to resolve. Both the broadband and the short period P wave data sets also reveal a sharp out-of-plane scatterer, which may be located close to the CMB. The short period data also indicate reflectivity about 400 km above the CMB, well above the D" discontinuity, and similar reflectivity is observed under the Central Pacific. This feature appears to be more consistent with a discontinuity than a scatterer

  3. Continuous subduction of oceanic crust into the deep mantle beneath central America

    Science.gov (United States)

    Kito, T.; Korenaga, J.

    2008-12-01

    Recent tomographic images imply that subducted slabs may penetrate into the lower mantle in some regions. However the behavior of the subducted materials around and below the mantle transition zone remains poorly understood. In order to investigate the fate of the subducted slab beneath central America, we have analyzed broadband teleseismic data from intermediate- and deep-earthquakes in south America recorded at several Californian seismic networks. To suppress artifacts and obtain a high resolution image, we have applied seismic migration method called Slowness Back azimuth Weighted Migration (SBWM) which utilizes not only travel time but also slowness and back azimuth information in the wavefield. We have observed reflected/scattered waves from heterogeneities associated with subduction processes. The migrated seismic energy has then been evaluated using the jackknife algorithm to determine statistically significant seismic signals. The observed reflected seismic waves can be explained by the subducted former oceanic lithosphere (MORB) in the deep mantle, which provides independent evidence for slab penetration into the lower mantle and mass transportation across the mantle transition zone, at least in this region.

  4. Extreme Short Scale Variations in D" Topography Beneath the Pacific Ocean Just West of Central America

    Science.gov (United States)

    Garnero, E. J.; Thomas, C.; Lay, T.

    2003-12-01

    In this study we use a wavefield migration technique to infer D" reflectance and topography in a densely sampled region just west of Central America beneath the Cocos plate. High quality broadband waveforms from seismic networks in California of 13 deep focus South American earthquakes are instrument and source wavelet deconvolved to displacement, aligned on ScS as a reference phase, then studied for coherency of energy between ScS and S. A search for potential lowermost mantle reflector locations is achieved by migrating the wavefield for each earthquake to each node of a 3D grid of potential reflector locations, with spacing every 1 deg laterally and 10 km vertically (with ranges: -2 to 18 deg N; -100 to -80 deg E, 2200 to 2888 km depth). Grouping our data into densely sampled latitudinal bins resulted in 41 clusters of bounce points between 0 and 15 deg N. The migrated images for all bounce point clusters show an abrupt increase in velocity that is thickest to the north in our study area (up to 300 km and greater) and dramatically reduces to as thin as 100 km thick in the south. We also see evidence for the main positive velocity increase being underlain by a negative velocity discontinuity in the northern half of our study region, though this feature is not visible in all migrations. These results are compatible with the general picture from simpler 1D studies (which indicate a thicker high velocity D" layer to the north beneath the neighboring Central American and Caribbean than that to the south) but demonstrate increased complexity at shorter scale lengths. The thickening of the D" layer to the north coincides with inference for higher velocities there implied by ScS-S and S-SKS differential travel time residuals. Evidence for out of plane reflections is also visible in some migrated images. Such strong topographical variations (~200 km change over several hundred km laterally) are likely intimately coupled to overlying mantle currents related to subduction

  5. Large-scale trench-normal mantle flow beneath central South America

    Science.gov (United States)

    Reiss, M. C.; Rümpker, G.; Wölbern, I.

    2018-01-01

    We investigate the anisotropic properties of the fore-arc region of the central Andean margin between 17-25°S by analyzing shear-wave splitting from teleseismic and local earthquakes from the Nazca slab. With partly over ten years of recording time, the data set is uniquely suited to address the long-standing debate about the mantle flow field at the South American margin and in particular whether the flow field beneath the slab is parallel or perpendicular to the trench. Our measurements suggest two anisotropic layers located within the crust and mantle beneath the stations, respectively. The teleseismic measurements show a moderate change of fast polarizations from North to South along the trench ranging from parallel to subparallel to the absolute plate motion and, are oriented mostly perpendicular to the trench. Shear-wave splitting measurements from local earthquakes show fast polarizations roughly aligned trench-parallel but exhibit short-scale variations which are indicative of a relatively shallow origin. Comparisons between fast polarization directions from local earthquakes and the strike of the local fault systems yield a good agreement. To infer the parameters of the lower anisotropic layer we employ an inversion of the teleseismic waveforms based on two-layer models, where the anisotropy of the upper (crustal) layer is constrained by the results from the local splitting. The waveform inversion yields a mantle layer that is best characterized by a fast axis parallel to the absolute plate motion which is more-or-less perpendicular to the trench. This orientation is likely caused by a combination of the fossil crystallographic preferred orientation of olivine within the slab and entrained mantle flow beneath the slab. The anisotropy within the crust of the overriding continental plate is explained by the shape-preferred orientation of micro-cracks in relation to local fault zones which are oriented parallel to the overall strike of the Andean range. Our

  6. Seismic Imaging of the Middle America Subduction Zone Beneath Mexico

    Science.gov (United States)

    Miller, M. S.; Kim, Y.; Pearce, F. D.; Clayton, R. W.

    2011-12-01

    P-wave coda from teleseismic events were used to compute receiver functions followed by formal inversions for discontinuous variations in elastic properties beneath a dense seismic array that crosses Mexico from Acapulco on the Pacific coast, through Mexico City, almost to Tempico on the Gulf of Mexico. Broadband data from the Meso-America Subduction Experiment (MASE) line were used to image the subducted Cocos plate and the overriding continental lithosphere beneath central Mexico using a generalized radon transform based migration. Our images provide insight into the process of subducting relatively young oceanic lithosphere. We observe nearly horizontal tectonic underplating of the Cocos oceanic lithosphere beneath the North American continent for a distance of approximately 300 km from the Middle America Trench, with a clear image of a very thin low-velocity oceanic crust (7-8 km) which dips at 15-20 degrees then flattens and slightly thickens (~10 km). At approximately 250 km inland the inferred subducting crust undergoes a change in seismic character, specifically a disruption in the crustal velocity signature, which may reflect the initiation of partial eclogitization of the subducting crust or release of fluids via dehydration that would result in a reduced velocity contrast at the Moho. Farther inland the slab then appears to abruptly change from nearly horizontal to a steeply dipping geometry of approximately 75 degrees underneath the Trans-Mexican Volcanic Belt (TMVB). The image of the steeply subducted Cocos slab underneath the TMVB is enhanced by using the P-to-S converted phases, following the method used in southern Central America to image a steeply dipping subducted slab (> 60 degrees) for the TUCAN experiment (MacKenzie et al, 2010), however is complicated by the wide active volcanic arc and deep sedimentary basins in the middle of the array. The continental Moho is clearly imaged at ~40 km deep beneath the TMVB and shallows (~25 km) towards the

  7. Central America's shrinking forests.

    Science.gov (United States)

    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.

  8. Mexico and Central America.

    Science.gov (United States)

    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.

  9. Demographic tensions in Central America.

    Science.gov (United States)

    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

  10. Anisotropic structure beneath central Java from local earthquake tomography

    Science.gov (United States)

    Koulakov, Ivan; Jakovlev, Andrey; Luehr, Birger G.

    2009-02-01

    In this study we present the new tomographic code ANITA which provides 3-D anisotropic P and isotropic S velocity distribution based on P and S traveltimes from local seismicity. For the P anisotropic model, we determine four parameters for each parameterization cell. This represents an orthorhombic anisotropy with one predefined direction oriented vertically. Three of the parameters describe slowness variations along three horizontal orientations with azimuths of 0°, 60°, and 120°, and one is a perturbation along the vertical axis. The nonlinear iterative inversion procedure is similar to that used in the LOTOS code. We have implemented this algorithm for the updated data set of central Java, part of which was previously used for the isotropic inversion. It was obtained that the crustal and uppermost mantle velocity structure beneath central Java is strongly anisotropic with 7-10% of maximal difference between slow and fast velocity in different directions. In the forearc (area between southern coast and volcanoes), the structure of both isotropic and anisotropic structure is strongly heterogeneous. Variety of anisotropy orientations and highly contrasted velocity patterns can be explained by a complex block structure of the crust. Beneath volcanoes we observe faster velocities in vertical direction, which is probably an indicator for vertically oriented structures (channels, dykes). In the crust beneath the middle part of central Java, north to Merapi and Lawu volcanoes, we observe a large and very intense anomaly with a velocity decrease of up to 30% and 35% for P and S models, respectively. Inside this anomaly E-W orientation of fast velocity takes place, probably caused by regional extension stress regime. In a vertical section we observe faster horizontal velocities inside this anomaly that might be explained by layering of sediments and/or penetration of quasi-horizontal lenses with molten magma. In the mantle, trench parallel anisotropy is observed

  11. Tectonic implications of tomographic images of subducted lithosphere beneath northwestern South America

    NARCIS (Netherlands)

    Hilst, R.D. van der; Mann, P.

    1994-01-01

    We used seismic tomography to investigate the complex structure of the upper mantle below northwestern South America. Images of slab structure not delineated by previous seismicity studies help us to refine existing tectonic models of subducted Caribbean-Pacific lithosphere beneath the study area.

  12. Biomass energy in Central America

    International Nuclear Information System (INIS)

    Blanco, J.M.

    1995-01-01

    The objective of this paper is to introduce the concept of biomass to energy issues and opportunities in Central America. In this region, made up of seven countries (Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama), the biomass sector has the potential to play a crucial role in alleviating the environmental and development predicaments faced by all economies of the region. This paper assesses the available biomass resources at the regional and country levels and gives an overview of the current utilization of biomass fuels. It also describes the overall context in which the biomass-to-energy initiatives are immersed. At the regional level, biomass energy consumption accounts for more than 50% of total energy consumption. In regard to the utilization of biomass for energy purposes, it is clear that Central America faces a critical juncture at two levels, both mainly in rural areas: in the productive sector and at the household level. The absence of sustainable development policies and practices has jeopardized the availability of biomass fuels, particularly wood. Firewood is an important source of energy for rural industries such as coffee processing, which is one of the largest productive activities in the region. This paper comments on some of the most successful technological innovations already in place in the region, for instance, the rapid development of co-generation projects by the sugar cane industry, especially in El Salvador and Guatemala, the substitution of coffee husks for firewood in coffee processing plants in Costa Rica and El Salvador and the sustainable use of pine forests for co-generation in Honduras. Only one out of every two inhabitants in Central America now has access to electricity from the public grid. Biomass fuels, mainly firewood but also, to a lesser extent, other crop residues such as corn stalks, are the main source of energy for cooking and heating by most of the population. (It is foreseen that by the end

  13. Central and South America GPS geodesy - CASA Uno

    Science.gov (United States)

    Kellogg, James N.; Dixon, Timothy H.

    1990-01-01

    In January 1988, scientists from over 25 organizations in 13 countries and territories cooperated in the largest GPS campaign in the world to date. A total of 43 GPS receivers collected approximately 590 station-days of data in American Samoa, Australia, Canada, Colombia, Costa Rica, Ecuador, New Zealand, Norway, Panama, Sweden, United States, West Germany, and Venezuela. The experiment was entitled CASA Uno. Scientific goals of the project include measurements of strain in the northern Andes, subduction rates for the Cocos and Nazca plates beneath Central and South America, and relative motion between the Caribbean plate and South America. A second set of measurements are planned in 1991 and should provide preliminary estimates of crustal deformation and plate motion rates in the region.

  14. Post-War Central America

    Directory of Open Access Journals (Sweden)

    Dirk Kruijt

    2003-10-01

    Full Text Available – Terror in the Countryside. Campesino Responses to Political Violence in Guatemala, 1954-1985, by Rachel A. May. Athens, Ohio: Ohio University Center for International Studies/Research in International Studies/Latin America Series #35, 2001. – La guerrilla fue mi camino. Epitafio para César Montes, by Julio César Macías. Guatemala: Piedra Santa/Colección Afluentes de Modernidad, 1999. – Testigo de conciencia (Periodismo de Opinión Documentado, by Marco A. Mérida. Guatemala: ARCASAVI, 2000. – Centroamérica 2002. Un nuevo modelo de desarrollo regional, edited by Klaus Bodemer and Eduardo Gamarra. Caracas: Nueva Sociedad, 2002. – Who Governs? Guatemala Five years After the Peace Accords, by Rachel Sieder, Megan Thomas, George Vickers and Jack Spence. Cambridge, Mass.: Hemispheric Initiatives/Washington Office on Latin America (WOLA, January 2002. – Pasos hacia una nueva convivencia: Democracia y participación en Centroamérica, edited by Ricardo Córdova Macías, Günther Maihold and Sabina Kurtenbach. San Salvador: FUNDAUNGO, Instituto de Estudios Iberoamericanos de Hamburgo and Instituto Iberoamericano de Berlin, 2001. – Los desafíos de la democracia en Centroamérica, by René Poitevin and Alexander Sequén-Mónchez. Guatemala: FLACSO, 2002. – Más allá de las elecciones: Diez años después de los acuerdos de paz, edited by Hector Dada Hirezi. San Salvador: FLACSO, 2002. – Guatemala, un proyecto inconcluso: La multiculturalidad, un paso hacia la democracia, by Hugo Cayzac. Guatemala: FLACSO, 2001. – La violencia en el contexto del posconflicto, según la percepción de comunidades urbanas pobres de Guatemala, by Caroline Moser and Cathy McIlwaine. Washington/Bogotá: Banco Mundial-Región de Latinoamérica y el Caribe/Tercer Mundo Editores, 2001. – El lado oscuro de la eterna primavera. Violencia, criminalidad y delincuencia en la postguerra, by Manolo Vela, Alexander Sequén-Mónchez and Hugo Antonio Solares

  15. Occupational health in Central America.

    Science.gov (United States)

    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.

  16. The Mediterranean fruit fly in Central America

    International Nuclear Information System (INIS)

    Vail, V.; Moore, I.; Nadel, D.

    1976-01-01

    Various methods of controlling the medfly are available and include the use of insecticides, bait sprays and the sterile insect technique (SIT). Each of these control strategies may be used alone or in sequence. With regard to the application of the SIT, the Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture through its Insect and Pest Control Section and Entomology Laboratory is in an excellent position to assist in containing the medfly in Central America. For the past 12 years, the laboratory has participated in all phases of medfly control by sterile insect releases in various climates. This involvement has included planning of medfly campaigns, development of pre-release techniques (bait spraying, trapping, etc.) and shipment and release of sterilized medflies. Small-scale field tests utilizing the SIT have been carried out by nine countries: Italy (Procida, Capri), Spain, Cyprus, Israel, Tunisia, Peru, Panama, Costa Rica and Nicaragua. Other field projects presently being counselled and serviced are located in Argentina, Venezuela and the Canary Islands. The research and development that are still needed to effectively stabilize and gain control of the medfly situation in Central America include: The development and use of effective quarantine procedures in various countries; Development of effective conventional medfly control procedures under the conditions found in Central America; Development of methods to determine the geographic origin of medflies introduced into new areas; Medfly mass production (viz. all aspects of rearing Central American strains); Assessing the performance (competitiveness, etc.) of various strains; Logistics, including the development of systems for releasing pre-adult stages; Genetic rearing methods: developmental research in this area is particularly promising since the preferential production of males would allow considerable savings in the rearing costs of medflies for release; Development of adequate surveillance

  17. Anisotropy tomography beneath east-central China and its geodynamic implications

    Science.gov (United States)

    Jiang, G.; Zhang, G.

    2017-12-01

    The east-central China primary consists of the southeastern part of the North China Block (NCB), the Middle-Lower Yangtze Block (MLYB), the northern part of Cathaysia Block (CB) and the Qinling-Dabie-Sulu Orogen (QDSO) (Fig. 1). Previous studies have suggested that both the rich mineralization in MLYB and the ultra-high pressure metamorphic belts in QDSO are closely to the Cretaceous magmatism in the east-central China. For discussing the geodynamic process, we have used the teleseismic tomography to study the 3D P-wave velocity structure down to 800 km deep and proposed a double-slab subduction model. In the present study, we introduce another two parameters representing the azimuthal anisotropy based on the isotropy tomography. Compared with the SKS method, the anisotropy tomography can provide the velocity anisotropy structure in different depths. The new anisotropy results show that (1) high-velocity (high-V) anomalies exist beneath the Middle Yangtze Block (MYB) from 200 km to 700 km depths and beneath the Lower Yangtze Block from 500 km to 700 km depths, and (2) low-velocity (low-V) anomalies exist beneath the Lower Yangtze Block from 50 km to 200 km depths and beneath the CB from 300 km to 700 km depths, respectively, and (3) the fast directions of P-wave velocity at 50-100 km depths are chaotic, however they show some regular changes from 200 km to 600 km depths. At 200-km deep, the fast direction of the low-V beneath the LYB is nearly E-W-trending. With the depth increasing, the fast directions of the low-V beneath the CB from 300 km to 600 km depths change to NEE-trending. In other side, the fast directions of eastern part of the high-V beneath the MYB, close to the low-V beneath the CB, denote NW-trending from 300 km to 600 depths. Combing with previous studies, we explain the high-V and the low-V, mentioned above, as the ancient Yangtze Craton and the upwelling asthenospheric materials, respectively. In addition, the NE-trending fast directions in the

  18. Sources of Economic Fluctuations in Central America

    Directory of Open Access Journals (Sweden)

    Wilfredo Toledo

    2014-06-01

    Full Text Available Using panel data from Central America, this paper studies the determining factors of inflation and aggregate output fluctuations by estimating two Structural Vector Autoregressive (SVAR models. Price and output variables are included in one of the models, whereas M2 and the price of oil are additional variables in the other one. Findings of this study suggest that price is determined by the demand, while output seems to be influenced mainly by the supply shocks in that area. It was also evidenced that the price of oil does not have a significant impact on the general price level in that region.

  19. Structure of Lithospheric and Upper Mantle Discontinuities beneath Central Mongolia from Receiver Functions

    Science.gov (United States)

    Cui, Z.; Meltzer, A.; Fischer, K. M.; Stachnik, J. C.; Munkhuu, U.; Tsagaan, B.; Russo, R. M.

    2017-12-01

    The origin and preservation of high-elevation low-relief surfaces in continental interiors remains an open questions. Central Mongolia constitutes a major portion of the Mongolian Plateau and is an excellent place to link deep earth and surface processes. The lithosphere of Mongolia was constructed through accretionary orogenesis associated with the Central Asian Orogenic Belt (CAOB) from the late Paleozoic to the early Triassic. Alkaline volcanic basalt derived from sublithospheric sources has erupted sporadically in Mongolia since 30 Ma. Constraining the depth variation of lithospheric and upper mantle discontinuities is crucial for understanding the interaction between upper mantle structure and surface topography. We conducted receiver functions (RF) analyses suitable data recorded at112 seismic broadband stations in central Mongolia to image the LAB and mantle transition zone beneath Central Mongolia. A modified H-κ stacking was performed to determine crustal average thickness (H) and Vp/Vs ratio (κ). Central Mongolia is characterized by thick crust (43-57 km) enabling use of both P wave RF and to S wave RF to image the LAB. The PRF traces in the depth domain are stacked based on piercing point locations for the 410 and 660 discontinuities using 0.6 ° × 0.6 ° bins in a grid. From south to north, the average lithospheric thickness is 85km in Gobi Altai gradually thinning northeastward to 78km in the southern Hangay Dome, 72 km in the northern Hangay Dome then increases to 75km in Hovsgol area. While there is overall thinning of the lithosphere from SW to NE, beneath the Hangay, there is a slight increase beneath the highest topography. The thickness of the mantle transition zone (MTZ) beneath central Mongolia is similar to global averages. This evidence argues against the hypothesis that a mantle plume exists beneath Central Mongolia causing low velocity anomalies in the upper mantle. To the east of the Hovsgol area in northern Mongolia, the MTZ thickens

  20. Regional Specialization. The Middle Americas: Mexico, Panama, Central America and the Caribbean Basin

    National Research Council Canada - National Science Library

    Owen, Mark H; Inman, Kenneth A

    1997-01-01

    .... Generally viewed as lagging in efforts to develop stable governments and self-sustaining economies, Mexico, Central America to include Panama and the Caribbean, henceforth Middle America, have in the...

  1. Legislation on renewable energy sources in Central America

    International Nuclear Information System (INIS)

    Rebollo, Jose

    2000-01-01

    This paper presents the development of renewable energy in Central America and the cooperation given by the European Comission in the promotion of renewable energy sources. Also discuss the current situation in energy demand in Central America and possible solutions linked to legislation that promotes the inversion of the private sector. The legal framework in each country of Central America is presented and its impact in the increasing of generation of energy through tax reductions, trading and prices

  2. Colored Height and Shaded Relief, Central America

    Science.gov (United States)

    2002-01-01

    Panama, Costa Rica, Nicaragua, El Salvador, Honduras, Guatemala, Belize, southern Mexico and parts of Cuba and Jamaica are all seen in this image from NASA's Shuttle Radar Topography Mission. The dominant feature of the northern part of Central America is the Sierra Madre Range, spreading east from Mexico between the narrow Pacific coastal plain and the limestone lowland of the Yucatan Peninsula. Parallel hill ranges sweep across Honduras and extend south, past the Caribbean Mosquito Coast to lakes Managua and Nicaragua. The Cordillera Central rises to the south, gradually descending to Lake Gatun and the Isthmus of Panama. A highly active volcanic belt runs along the Pacific seaboard from Mexico to Costa Rica.High-quality satellite imagery of Central America has, until now, been difficult to obtain due to persistent cloud cover in this region of the world. The ability of SRTM to penetrate clouds and make three-dimensional measurements has allowed the generation of the first complete high-resolution topographic map of the entire region. This map was used to generate the image.Two visualization methods were combined to produce the image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red, and magenta, to white at the highest elevations.For an annotated version of this image, please select Figure 1, below: [figure removed for brevity, see original site] (Large image: 9 mB jpeg)Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect

  3. Spatial variations of P wave attenuation in the mantle beneath North America

    Science.gov (United States)

    Hwang, Yong Keun; Ritsema, Jeroen; Goes, Saskia

    2009-06-01

    We estimate the spatial variation of the seismic parameter t* using teleseismic (epicentral distance = 30°-85°) P wave spectra of about 200 deep (focal depths > 200 km) earthquakes recorded by 378 broadband seismometers in the United States and Canada. Relative P wave spectral ratios up to 1 Hz for about 63,000 station pairs with high signal-to-noise ratio and impulsive P waveforms are inverted for t*P by least squares inversion. The continental-scale t*P pattern correlates to the age of geological terrains and the seismic, heat flow, gravity, and magnetic variations across North America. Predominantly low values of t*P are obtained in stable central North America (SNA), and high t*P values are obtained for stations in the tectonically active western part of the continent (TNA). This variation is similar to that observed previously in short-period amplitude anomalies, spectral ratio variations, and ScS reverberations. On average, we resolve a contrast in t*P between SNA and TNA of about 0.2 s. We resolve regional variations in t*P, which correlate with tectonics. Relatively low t*P is associated with currently active subduction below Alaska. Relatively high t*P is found in SNA below the Appalachians and the Gulf Coast. The consistency between t*P and tectonics suggests that the observed variations in t*P are, on the scale of around 200-500 km, predominantly due to intrinsic attenuation. The similar patterns in t*P and predicted values for a recent global attenuation model confirm this further. The compatibility with the t*P computed for attenuation estimated via a thermal interpretation of shear wave velocity anomalies illustrates that variations in seismic velocity are predominantly due to physical effects with a strong attenuation signature, most likely temperature or a combination of temperature and water content.

  4. The rock coast of South and Central America : chapter 10

    OpenAIRE

    Blanco-Chao, R.; Pedoja, K.; Witt, C.; Martinod, J.; Husson, L.; Regard, V.; Audin, Laurence; Nexer, M.; Delcaillau, B.; Saillard, M.; Melnick, D.; Dumont, J.F.; Santana, E.; Navarrete, E.; Martillo, C.

    2014-01-01

    The great variety of climatic conditions, tidal ranges and wave regimes of South and Central America act on a complex geology and tectonic framework. Many of the rock and cliffed coasts of South America are strongly controlled by the occurrence of extensive Cenozoic and Pleistocene sediments that crop out at the coast. Geology and the different uplift rates are a major factor in the whole coastal geomorphology of South and Central America, and consequently are a very important control of the ...

  5. Energy sector developments in Central America and the Caribbean

    International Nuclear Information System (INIS)

    Perez, J.

    1997-01-01

    Energy sector developments in Central America and the Caribbean were discussed. Central America is composed of six small countries whose total population is 32 million. The Caribbean population is 20.5 million. Central America is generally poor in hydrocarbon reserves but the geological prospects in several of the countries are encouraging. The oil and petroleum products supply and demand picture, the main characteristics of the hydrocarbon market, structure of the oil industry, hydrocarbon market reforms, pricing issues and recent trend towards reforms in the electric power industry in Central America were discussed. An overview of the Inter-American Development Bank's (IDB) effort to provide technical assistance and loans to strengthen the energy sector development in Central America and the Caribbean was also given. 17 refs., 2 tabs., 23 figs

  6. Total adult cardiovascular risk in Central America

    Directory of Open Access Journals (Sweden)

    A. Barceló

    Full Text Available OBJECTIVE:To evaluate prevalence of cardiovascular risk among adults 40 years and older using population-based samples from six Central American countries. METHODS: Risk factors were derived from a multi-national cross-sectional survey implemented in 2003-2006, which included a sample of 4 202 participants aged 40 years and older. Charts produced by the World Health Organization and the International Society of Hypertension for the Region of the Americas sub-region B were used to predict risk on the basis of factors including age, sex, blood pressure, total serum cholesterol, smoking status, and diabetes status. RESULTS: Overall, 85.9% of the population was classified as having 20% risk. More than 75% of those with a 30-40% risk had previously been identified by health services, and an additional 23% were identified during the study, suggesting they could be diagnosed by opportunistic screening for diabetes, hypertension and hypercholesterolemia. Results of bivariate analysis showed that respondents who were male, older, obese and/or less educated had higher risk for cardiovascular events, but a multivariate analysis including education indicated highest risks for older, obese, and less educated females. CONCLUSIONS: Measuring cardiovascular disease risk identifies most cases of (or at risk for diabetes, hypertension and hypercholesterolemia among adults 40 years and older. This strategy can facilitate implementation of control programs and decrease disabilities and premature mortality.

  7. Regional Strategic Appraisal of Central America

    Science.gov (United States)

    2003-04-07

    final_eng.pdf>; Internet accessed 12 November 2002. CEPAL, “Panorama Social de America Latina 2001-2002, Documento Informativo”; available from <http... America Report, No 2, December 1995; ”; available from <http://www.us.net/cip/dialogue/9512in02htm>. Internet accessed 20 January 2003. 24 Núñez, Joseph, A...Observatorio de Seguridad y Defensa en America Latina (OSAL), Instituto Universitario Ortega y Gasset. 38 Ibid. 26 BIBLIOGRAPHY Agosin, Manuel R., David

  8. Crustal-scale electrical conductivity anomaly beneath inflating Lazufre volcanic complex, Central Andes

    Science.gov (United States)

    Budach, Ingmar; Brasse, Heinrich; Díaz, Daniel

    2013-03-01

    Large-scale surface deformation was observed at Lazufre volcanic center in the Central Andes of Northern Chile/Northwestern Argentina by means of Interferometric Synthetic Aperture Radar (InSAR). Uplift started there after 1998 and increased dramatically in the following years up to a rate of 3 cm/a. Lazufre is now one of the largest deforming volcano systems on Earth, but the cause for uplift - likely influx of magmatic material into the crust - is still poorly understood. In the beginning of 2010 a magnetotelluric survey was conducted to delineate the electrical conductivity distribution in the area. Several long-period magnetotelluric (LMT) sites and two broadband magnetotelluric (BBMT) sites were set up on an EW trending profile crossing the volcanic center; furthermore some LMT sites were arranged circularly around Lazufre complex and adjacent Lastarria volcano. Data were processed using an algorithm for robust and remote reference transfer function estimation. Electrical strike directions were estimated and induction arrows were derived. Although electrical strike is rather ambiguous, in a first step a 2-D resistivity model was calculated. The most prominent feature of this model is a well conducting structure rising from the upper mantle to the shallow crust beneath the center of elevation. This can be interpreted as partial melts ascending from the asthenospheric wedge and feeding a potential magma reservoir beneath Lazufre volcanic center. An improved model is finally achieved by 3-D inversion, supporting this feature. We assume that these rising melts are the source of the observed uplift at Lazufre complex.

  9. Current situation of Chagas disease in Central America

    Directory of Open Access Journals (Sweden)

    Carlos Ponce

    2007-10-01

    Full Text Available Chagas disease in Central America is known since 1913 when the first human case was reported in El Salvador. The other Central American countries reported their first cases between 1933 and 1967. On October 1997 was launched the Central American Initiative for Chagas Disease Control (IPCA. The objectives of this sub-regional Initiative are: (1 the elimination of Rhodnius prolixus in Central America; (2 the reduction of the domiciliary infestation of Triatoma dimidiata; and (3 the elimination of the transfusion transmission of Trypanosoma cruzi. Significant advancements being close to the elimination of R. prolixus in Central America and the control of the transfusion transmission has been a transcendent achievement for the sub-region. The main challenges that the IPCA will have in the close future are: developing effective strategies for control and surveillance of T. dimidiata; and surveillance of other emerging triatominae species like R. pallescens, T. nitida, and T. ryckmani.

  10. Dissolved phosphorus distribution in shallow groundwater beneath dairy farms, Central Valley, California

    Science.gov (United States)

    Young, M. B.; Lockhart, K.; Holstege, D.; Applegate, O.; Harter, T.

    2012-12-01

    Concentrated animal farming operations (CAFOs) often produce surface runoff with high phosphorus (P) concentrations, but much less is known about P leaching and distributions in shallow groundwater beneath CAFOs. In this study, concentrations of soluble P were measured in shallow groundwater beneath ten dairies located in the Central Valley, California between 1998 and 2009 to assess spatial and temporal variability in areas of higher and lower hydrogeological vulnerability to groundwater contamination, and to investigate both land uses and physiochemical parameters associated with soluble P distribution. Distribution of bioavailable soil phosphate (bicarbonate extraction) was also examined in soil cores from several of the dairies in order to asses potential links between P distribution in the vadose zone and dissolved P concentrations near the top of the groundwater table. Dissolved P and other geochemical constituents were measured in 200 domestic drinking water wells to examine differences in shallow and deeper groundwater within the region. Samples from dairies and domestic wells were collected from two distinct regions in the Central Valley. The northern region (northeastern San Joaquin Valley) is characterized by a shallower water table, sandy soils, and groundwater discharges to surface water, whereas the southern region (Tulare Lake Basin) is characterized by a much deeper water table and does not have natural discharges of groundwater to surface water. Mean dissolved P concentrations were highest in the two dairies with the shallowest water table and sandiest soils, although dissolved P concentrations were highly variable across monitoring wells within individual dairies. Dissolved P ranged from below detection (waste lagoons, corrals, and manured fields); however phosphate concentrations in soil cores appeared to be strongly influenced by dairy land use, with the highest values occurring in cores adjacent to waste lagoons, followed by cores taken from

  11. Private Higher Education in a Cold War World: Central America

    Science.gov (United States)

    Harrington, James J.

    2009-01-01

    In Central America the Cold War support of the elites by the United States was designed to ward off the communist threat. At the same time social and economic demands by the working and middle classes created revolutionary movements in the face of rigid and violent responses by Central American governments. Issues of social justice pervaded the…

  12. Seismic imaging of the upper mantle beneath the northern Central Andean Plateau: Implications for surface topography

    Science.gov (United States)

    Ward, K. M.; Zandt, G.; Beck, S. L.; Wagner, L. S.

    2015-12-01

    Extending over 1,800 km along the active South American Cordilleran margin, the Central Andean Plateau (CAP) as defined by the 3 km elevation contour is second only to the Tibetan Plateau in geographic extent. The uplift history of the 4 km high Plateau remains uncertain with paleoelevation studies along the CAP suggesting a complex, non-uniform uplift history. As part of the Central Andean Uplift and the Geodynamics of High Topography (CAUGHT) project, we use surface waves measured from ambient noise and two-plane wave tomography to image the S-wave velocity structure of the crust and upper mantle to investigate the upper mantle component of plateau uplift. We observe three main features in our S-wave velocity model including (1), a high velocity slab (2), a low velocity anomaly above the slab where the slab changes dip from near horizontal to a normal dip, and (3), a high-velocity feature in the mantle above the slab that extends along the length of the Altiplano from the base of the Moho to a depth of ~120 km with the highest velocities observed under Lake Titicaca. A strong spatial correlation exists between the lateral extent of this high-velocity feature beneath the Altiplano and the lower elevations of the Altiplano basin suggesting a potential relationship. Non-uniqueness in our seismic models preclude uniquely constraining this feature as an uppermost mantle feature bellow the Moho or as a connected eastward dipping feature extending up to 300 km in the mantle as seen in deeper mantle tomography studies. Determining if the high velocity feature represents a small lithospheric root or a delaminating lithospheric root extending ~300 km into the mantle requires more integration of observations, but either interpretation shows a strong geodynamic connection with the uppermost mantle and the current topography of the northern CAP.

  13. Oil supply in Central and South America

    International Nuclear Information System (INIS)

    Aguilera, Roberto F.

    2009-01-01

    This paper estimates a cumulative supply curve for conventional oil in the Central and South American (CSA) region. The curve includes volumes from provinces not previously assessed by other organizations, as well as reserve growth. Volumes for the previously unassessed provinces are estimated using a variable shape distribution (VSD) model. Then the volumes are allocated to CSA countries based on each country's share of proved reserves. Figures provided by the cumulative supply curve are stock variables for all time, unlike the traditional supply curve where they are flow variables that can continue from one period to the next. In this study, the fixed stock approach is used since it provides practical information with respect to the concerns that some have expressed about oil scarcity in the near future. Results indicate that Central and South American oil is more abundant than often assumed, and can be produced at costs below current market oil prices, and substantially below mid-2008 prices.

  14. 75 FR 53370 - RailAmerica, Inc., Palm Beach Holding, Inc., RailAmerica Transportation Corp., Central Railroad...

    Science.gov (United States)

    2010-08-31

    ...., Palm Beach Holding, Inc., RailAmerica Transportation Corp., Central Railroad Company of Indianapolis... requirements of 49 U.S.C. 11323-25, for RailAmerica, Inc. (RailAmerica); Palm Beach Holding, Inc. (Palm Beach... Acquisition, RailAmerica, Palm Beach, and RTC will indirectly control DTC, because Fortress's noncarrier...

  15. The Baltic Klint beneath the central Baltic Sea and its comparison with the North Estonian Klint

    Science.gov (United States)

    Tuuling, Igor; Flodén, Tom

    2016-06-01

    Along its contact with the Baltic Shield, the margin of the East European Platform reveals a well-developed, flooded terraced relief. The most striking and consistent set of escarpments at the contact of the Lower Palaeozoic calcareous and terrigenous rocks, known as the Baltic Klint (BK), extends from northwest of Russia to the Swedish island of Öland. Marine seismic reflection profiling in 1990-2004 revealed the central Baltic Sea Klint (BSK) section in detail and enabled comparison of its geology/geomorphology with a classical klint-section onshore, namely the North Estonian Klint (NEK). The conception of the BK onshore, which is based on the land-sea separating terraced relief in northern Estonia, is not fully applicable beneath the sea. Therefore, we consider that the BSK includes the entire terraced Cambrian outcrop. We suggest the term "Baltic Klint Complex" to include the well-terraced margin of the Ordovician limestone outcrop, which is weakly developed in Estonia. Because of a steady lithological framework of the bedrock layers across the southern slope of the Fennoscandian Shield, the central BSK in the western and the NEK in the eastern part of the Baltic Homocline have largely identical morphologies. The North Estonian Ordovician limestone plateau with the calcareous crest of the BK extends across the central Baltic Sea, whereas morphological changes/variations along the Klint base occur due to the east-westerly lithostratigraphic/thickness changes in the siliciclastic Cambrian sequence. The verge of the NEK, located some 30-50 m above sea level, starts to drop in altitude as its east-westerly course turns to northeast-southwest in western Estonia. Further westwards, the BK shifts gradually into southerly deepening (0.1-0.2°) layers as its crest drops to c. 150 m below sea level (b.s.l.) near Gotska Sandön. This course change is accompanied by a considerable decrease in thickness of the platform sedimentary cover, as below the central Baltic Sea the

  16. Research tracks growing violence against women in Central America

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-06-21

    Jun 21, 2016 ... Violence against women and female homicides or femicide, is escalating across Central America. And despite the efforts of women's organizations, human rights groups, regional governments, and civil society to stem these crimes, incidents of violence against women remain vastly underreported.

  17. National Geothermal Association Trade Mission to Central America

    International Nuclear Information System (INIS)

    1992-10-01

    The United States (US) geothermal industry, the world's most technically proficient, has been unable to achieve penetration into the markets of the developing nations. This report details the findings of an industry Trade Mission to Central America, tasked with determining the reasons for this shortfall and with developing a US industry geothermal export strategy designed to achieve immediate and long-term export benefits

  18. Youth employment to reduce violence in Central America | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    According to 2014 statistics, four out of the 10 countries with the highest homicide rates in the world are in Central America. The vast majority of victims of violence are young men between the ages of 15 and 24, some of whom also risk becoming perpetrators of violence. Access to jobs, in both formal and informal labour ...

  19. Water Security and Climate Change in Central America and the ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Recent studies show that water shortages in Central America and the Caribbean will be aggravated by urban growth, high poverty rates, weak institutions, and insufficient investment in water and sanitation infrastructure. Extreme climatic events are expected to further threaten water supply as well as affect economic sectors ...

  20. Harmonization of Legislation against Organized Crime in Central America

    Directory of Open Access Journals (Sweden)

    Jaime Edwin Martínez Ventura

    2014-05-01

    Full Text Available With the expansion of organized crime in Central America, the countries in this continental sub-region have enacted a great deal of internal legislation, and have ratified international treaties at the universal, regional and Central American level, particularly after the United Nations Convention against Transnational Organized Crime took effect in 2000.This abundance of laws is very positive, and is an expression of these Central American States’ intent to fulfill their supranational obligations and provide security for their inhabitants. However, it is also negative in that it has led to dispersion, dislocation, discrepancies and inaccuracies regarding the prevailing legal regulations, because national laws have been developed with different concepts, structures, approaches, scope and definitions.Despite these conditions that are adverse to legal harmonization, Central America can move forward with matching its legislation against organized crime. Actually, there already exists an extensive common legal framework in this area, expressed in the fact that most international treaties on Organized Crime have come into force at the universal, regional and subregional levels, ratified by all or most countriesPolitical will is the common denominator that should mediate all efforts of harmonization and alignment of legislation in Central America; it is essential for proposing steps that are based on a common strategy or program.DOI: http://dx.doi.org/10.5377/rpsp.v1i2.1359

  1. Social determinants of workers' health in Central America.

    Science.gov (United States)

    Aragón, Aurora; Partanen, Timo; Felknor, Sarah; Corriols, Marianela

    2011-01-01

    This communication summarizes the available data on work-related determinants of health in Central America. The Central American working population is young and moving from agriculture toward industry and services. Ethnicity, gender, migration, subemployment and precarious work, informality, rural conditions, low-level educational, poverty, ubiquitous worksite health hazards, insufficient occupational health services, low labor inspection density, and weak unions define the constellation of social determinants of workers' health in Central America. Data are, however, scanty both for hazards and work-related illnesses and injuries. Governments and industries have the responsibility of opening decent work opportunities, especially for those facing multiple inequalities in social determinants of health. A first step would be the ratification and implementation of the ILO Convention (187) on occupational safety and health by the seven national governments of the region.

  2. A preliminary analysis of emigration determinants in Mexico, Central America, northern South America and the Caribbean.

    Science.gov (United States)

    Castillo, M A

    1994-01-01

    The author examines migratory movements and their causes in Mexico, Central and South America, and the Caribbean. Sections are included on migration trends, theoretical approaches, and methodological tools before the 1970s; the shift in migratory patterns after the 1980s; macrosocial variables as a general background of current international flows; and migration policies.

  3. Central America: Region in Conflict; A Selective Bibliography.

    Science.gov (United States)

    1983-09-01

    abstracts see "Abstracting Sientific ed Technical Reports of Defense-Sponsored RDT&3."""- %, -’ p 4 ,’ 0 0 ." .. ’ ..\\ a U.S. Q t$74-540-847102. ... % % F...Santa Monica, CA: Rand, 1982. 10 p. Q180 .Al R16 No. 6752 THE AMERICAS AT A CROSSROADS: REPORT OF THE INTER- AMERICAN DIALOGUE. Washington, DC: Woodrow...Wilson International Center for Scholars Latin American Program, 1983. 63 p. P1408 .A65 1983 Anderson, Thomas P. POLITICS IN CENTRAL AMERICA: GUATEMALA

  4. Remittances in Central America: Whose Money is it Anyway?

    Directory of Open Access Journals (Sweden)

    Jose Luis Rocha

    2015-08-01

    Full Text Available In opposition to optimistic visions that present remittances as an opportunity for developing countries, this paper shows they are part and parcel of a process of economic imperialism, whereby their use and final destinations are strictly conditioned. In order to go beyond a conception of remittances as epiphenomenon, and in order to trace the role they play, this paper focuses on the transnational strategies of capital. It finds that remittances enable an increase in foreign investment and import production by facilitating the rise of a new class of consumers in Central America. Remittances create and feed a purchasing power that would not exist in their absence. Factories, fast food restaurants, communications companies, banks, travel agencies, and supermarkets are opening new branches throughout Central America in order to benefit from transnational savings that would otherwise be used differently. In this way, remittances are conditioned and co-opted by transnational capital’s strategies to sustain an ever growing market, with Central America more generally – and once again – potentially at risk of becoming characterized by enclave economies and chronic commercial deficits. The remittance-based economic model furthermore cannot be sustainable in the long run unless Central American countries keep exporting workers ad infinitum, something that is obviously not possible.

  5. Narco-scapes: Cocaine Trafficking and Deforestation in Central America

    Science.gov (United States)

    Wrathall, D.; McSweeney, K.; Nielsen, E.; Pearson, Z.

    2015-12-01

    Narcotics trafficking and drug interdiction efforts have resulted in a well-documented social crisis in Central America, but more recently, has been tightly linked to environmental catastrophe and accelerated deforestation in transit zones. This talk will outline synthesis findings from multi-country, interdisciplinary research on cocaine trafficking as an engine of forest loss in Central America. During the "narco-boom" of the mid-2000s, we observed a geographical evolution of cocaine flows into Central America, and the transit of cocaine through new spaces, accompanied by specific patterns of social and environmental change in new nodes of transit. We coarsely estimated that the total amount of cocaine flowing through Central America increased from 70 metric tons in 2000 to 350 mt in 2012, implying that total cocaine trafficking revenue in the region increased from roughly 600 million dollars to 3.5 billion in that time. We describe the mechanism by which these locally captured cocaine rents resulted in a rapid conversion of forest into cattle pasture. Narco-traffickers are drawn to invest in the cattle economy, as a direct means of laundering and formalizing proceeds. Ranching is a land intensive activity, and new narco-enriched cattle pastures can be isolated from other forms forest loss solely by their spatial and temporal change characteristics. A preliminary forest change study in Honduras, for example, indicated that areas of accelerated deforestation were in close proximity to known narcotics trafficking routes and were thirteen times more extensive on average than other forest clearings. Deforested areas commonly appeared in isolated and biodiverse lowland tropical rainforest regions that often intersected with protected areas and indigenous reserves. We find that narco-deforestation is a readily identifiable signal of the extent and health of the cocaine economy. This talk will feature summaries of both ethnographic and land cover change we have observed

  6. National Geothermal Association Trade Mission to Central America

    Energy Technology Data Exchange (ETDEWEB)

    1992-10-01

    The United States (US) geothermal industry, the world's most technically proficient, has been unable to achieve penetration into the markets of the developing nations. This report details the findings of an industry Trade Mission to Central America, tasked with determining the reasons for this shortfall and with developing a US industry geothermal export strategy designed to achieve immediate and long-term export benefits.

  7. National Geothermal Association Trade Mission to Central America

    Energy Technology Data Exchange (ETDEWEB)

    1992-10-01

    The United States (US) geothermal industry, the world`s most technically proficient, has been unable to achieve penetration into the markets of the developing nations. This report details the findings of an industry Trade Mission to Central America, tasked with determining the reasons for this shortfall and with developing a US industry geothermal export strategy designed to achieve immediate and long-term export benefits.

  8. Mapping the mantle transition zone beneath the central Mid-Atlantic Ridge using Ps receiver functions.

    Science.gov (United States)

    Agius, M. R.; Rychert, C.; Harmon, N.; Kendall, J. M.

    2017-12-01

    Determining the mechanisms taking place beneath ridges is important in order to understand how tectonic plates form and interact. Of particular interest is establishing the depth at which these processes originate. Anomalies such as higher temperature within the mantle transition zone may be inferred seismically if present. However, most ridges are found in remote locations beneath the oceans restricting seismologists to use far away land-based seismometers, which in turn limits the imaging resolution. In 2016, 39 broadband ocean-bottom seismometers were deployed across the Mid-Atlantic Ridge, along the Romanche and Chain fracture zones as part of the PI-LAB research project (Passive Imaging of the Lithosphere and Asthenosphere Boundary). The one-year long seismic data is now retrieved and analysed to image the mantle transition zone beneath the ridge. We determine P-to-s (Ps) receiver functions to illuminate the 410- and 660-km depth mantle discontinuities using the extended multitaper deconvolution. The data from ocean-bottom seismometers have tilt and compliance noise corrections and is filtered between 0.05-0.2 Hz to enhance the signal. 51 teleseismic earthquakes generated hundreds of good quality waveforms, which are then migrated to depth in 3-D. The topography at the d410 deepens towards the west of the Romanche and Chain fracture zone by 15 km, whereas the topography of d660 shallows beneath the ridge between the two zones. Transition zone thickness thins from 5 to 20 km. Thermal anomalies determined from temperature relationships with transition zone thickness and depth variations of the d410 and d660 suggests hotter temperatures of about 200 K. Overall, the result suggests mid-ocean ridges may have associated thermal signatures as deep as the transition zone.

  9. P and S velocity structure of the crust and the upper mantle beneath central Java from local tomography inversion

    Science.gov (United States)

    Koulakov, I.; Bohm, M.; Asch, G.; Lühr, B.-G.; Manzanares, A.; Brotopuspito, K. S.; Fauzi, Pak; Purbawinata, M. A.; Puspito, N. T.; Ratdomopurbo, A.; Kopp, H.; Rabbel, W.; Shevkunova, E.

    2007-08-01

    Here we present the results of local source tomographic inversion beneath central Java. The data set was collected by a temporary seismic network. More than 100 stations were operated for almost half a year. About 13,000 P and S arrival times from 292 events were used to obtain three-dimensional (3-D) Vp, Vs, and Vp/Vs models of the crust and the mantle wedge beneath central Java. Source location and determination of the 3-D velocity models were performed simultaneously based on a new iterative tomographic algorithm, LOTOS-06. Final event locations clearly image the shape of the subduction zone beneath central Java. The dipping angle of the slab increases gradually from almost horizontal to about 70°. A double seismic zone is observed in the slab between 80 and 150 km depth. The most striking feature of the resulting P and S models is a pronounced low-velocity anomaly in the crust, just north of the volcanic arc (Merapi-Lawu anomaly (MLA)). An algorithm for estimation of the amplitude value, which is presented in the paper, shows that the difference between the fore arc and MLA velocities at a depth of 10 km reaches 30% and 36% in P and S models, respectively. The value of the Vp/Vs ratio inside the MLA is more than 1.9. This shows a probable high content of fluids and partial melts within the crust. In the upper mantle we observe an inclined low-velocity anomaly which links the cluster of seismicity at 100 km depth with MLA. This anomaly might reflect ascending paths of fluids released from the slab. The reliability of all these patterns was tested thoroughly.

  10. Acute pesticide poisoning and pesticide registration in Central America

    International Nuclear Information System (INIS)

    Wesseling, Catharina; Corriols, Marianela; Bravo, Viria

    2005-01-01

    The International Code of Conduct on the Distribution and Use of Pesticides of the Food and Agriculture Organization (FAO) of the United Nations has been for 20 years the most acknowledged international initiative for reducing negative impact from pesticide use in developing countries. We analyzed pesticide use and poisoning in Central America, particularly in Costa Rica and Nicaragua, and evaluated whether registration decisions are based on such data, in accordance with the FAO Code. Extensive use of very hazardous pesticides continues in Central America and so do poisonings with organophosphates, carbamates, endosulfan and paraquat as the main causative agents. Central American governments do not carry out or commission scientific risk assessments. Instead, guidelines from international agencies are followed for risk management through the registration process. Documentation of pesticide poisonings during several decades never induced any decision to ban or restrict a pesticide. However, based on the official surveillance systems, in 2000, the ministers of health of the seven Central American countries agreed to ban or restrict twelve of these pesticides. Now, almost 4 years later, restrictions have been implemented in El Salvador and in Nicaragua public debate is ongoing. Chemical and agricultural industries do not withdraw problematic pesticides voluntarily. In conclusion, the registration processes in Central America do not comply satisfactorily with the FAO Code. However, international regulatory guidelines are important in developing countries, and international agencies should strongly extend its scope and influence, limiting industry involvement. Profound changes in international and national agricultural policies, steering towards sustainable agriculture based on non-chemical pest management, are the only way to reduce poisonings

  11. S-Wave Velocity Structure beneath Southwest North America from Seismogram Comparisons of the Mexico Earthquake on 22 June 1997

    Directory of Open Access Journals (Sweden)

    Bagus Jaya Santosa

    2008-09-01

    Full Text Available This research investigates earth structure beneath the Southwest North America landmass, especially between Mexico and California. Models based on S wave velocities for this area were obtained by carrying out seismogram fitting in time domain and three Cartesian components simultaneously. The data used is from an event, coded as C052297B that occurred in the state of Guerrero, Mexico and it was fitted to synthetic data computed with the GEMINI program at TS network stations. Earth model IASPEI91 and SPREM were used as input to create the synthetic data. Real and synthetic seismograms were subjected to a low-pass filter with a frequency corner of 20 mHz.Waveform analysis results show very unsystematic and strong deviations in the waveform, arrival times, amount of oscillation and the height of the wave amplitude. Discrepancies are met on S, Love, Rayleigh and ScS waves, where the stations epicentral distances are below 300. Deviation in analysis waveform because of the usage of model 1-D of SPREM and IASPEI91, because the 1-D was a kind of average value an elastic property at one particular depth of global earth. With the method of waveform analysis we can see how sensitive waveform is to structures within the layers of the Earth.To explain the discrepancies, a correction to the earth structure is essential. The corrections account for the thickness of the crust, speed gradient of bh, the coefficient for the bh and bv in the upper mantle for surface wave fitting, a small variation of the S speed structure at a layer under the upper mantle above 771 km for S wave fitting, and a small variation at the base the mantle layers for ScS wave fitting. At some stations, a correction for S speed structure have yielded P wave fitting. Results of this research indicate that the 1-D earth model obtained through seismogram fitting at every hypocenter-observation station pair is unique. The S-wave velocity on the upper mantle has strong negative anomalies. This

  12. Structure of magma reservoirs beneath Merapi and surrounding volcanic centers of Central Java modeled from ambient noise tomography

    Science.gov (United States)

    Koulakov, Ivan; Maksotova, Gulzhamal; Jaxybulatov, Kayrly; Kasatkina, Ekaterina; Shapiro, Nikolai M.; Luehr, Birger-G.; El Khrepy, Sami; Al-Arifi, Nassir

    2016-10-01

    We present a three-dimensional model of the distribution of S-wave velocity in the upper crust to a depth of 20 km beneath Central Java based on the analysis of seismic ambient noise data recorded by more than 100 seismic stations in 2004 associated with the MERAMEX project. To invert the Rayleigh wave dispersion curves to construct 2-D group-velocity maps and 3-D distributions of S-wave velocity, we have used a new tomographic algorithm based on iterative linearized inversion. We have performed a series of synthetic tests that demonstrate significantly higher resolution in the upper crust with this model compared to the local earthquake travel-time tomography (LET) model previously applied for the same station network. Beneath the southern flank of Merapi, we identify a large low-velocity anomaly that can be split into two layers. The upper layer reflects the ˜1 km thick sedimentary cover of volcanoclastic deposits. The deeper anomaly at depths of ˜4-8 km may represent a magma reservoir with partially molten rock that feeds several volcanoes in Central Java. Beneath the Merapi summit, we observe another low-velocity anomaly as deep as 8 km that may be associated with the active magma reservoir that feeds the eruptive activity of Merapi. In the southern portion of the study area, in the lower crust, we identify a low-velocity anomaly that may represent the top of the pathways of volatiles and melts ascending from the slab that was previously inferred from the LET model results. We observe that this anomaly is clearly separate from the felsic magma reservoirs in the upper crust.

  13. Observations of SKS splitting beneath the Central and Southern External Dinarides in the Adria-Eurasia convergence zone

    Science.gov (United States)

    Subašić, Senad; Prevolnik, Snježan; Herak, Davorka; Herak, Marijan

    2017-05-01

    Seismic anisotropy beneath the greater region of the Central and Southern External Dinarides is estimated from observations of SKS splitting. The area is located in the broad and complex Africa-Eurasia convergent plate boundary zone, where the Adriatic microplate interacts with the Dinarides. We analyzed recordings of 12 broadband seismic stations located in the Croatian coastal region. Evidence of seismic anisotropy was found beneath all stations. Fast axis directions are oriented approximately in the NE-SW to NNE-SSW direction, perpendicularly to the strike of the Dinarides. Average delay times range between 0.6 and 1.0 s. A counter-clockwise rotation in average fast axis directions was observed for the stations in the northern part with respect to the stations in the southern part of the studied area. Fast axis directions coincide with the assumed direction of asthenospheric flow through a slab-gap below the Northern and Central External Dinarides, with the maximum tectonic stress orientation in the crust, and with fast directions of Pg and Sg-waves in the crust. These observations suggest that the detected SKS birefringence is primarily caused by the preferred lattice orientation of mantle minerals generated by the asthenospheric flow directed SW-NE to SSW-NNE, with a possible contribution from the crust.

  14. Politics in education quality policies in Central America

    Directory of Open Access Journals (Sweden)

    Juan MUÑOZ PORTILLO

    2018-01-01

    Full Text Available This paper analyses the adoption of education policies in Central America and Panama during the 2010 decade in three areas: the increase in education expenditure, curricular reforms and teacher recruitment and evaluation rules. The paper argues that greater foreign direct investment and more international trade are associated with the adoption of these policies. This, in turn, relates to the incentives produced by varieties of capitalism within the region. It is hypothesised that conservative governments under systems with stronger executive powers, have a preference for policy reform in teacher recruitment and evaluation. Historical factors contribute to explain policy change in Costa Rica and the statu quo in Guatemala.

  15. Violence, Rule of Law, and Punitive Policies in Central America

    Directory of Open Access Journals (Sweden)

    Verónica De la Torre

    2011-01-01

    Full Text Available This article suggests that high levels of violence and crime in the so called North Triangle of Central America (Guatemala, El Salvador and Honduras, together with the incapacity of the state of enforcing the rule of law, are causing growing anxiety among the population and are attracting the support of the community to implement authoritarian measures to fight crime. The response of the governments of the region in the face of the rise of crime and public demand for security has been the policies of "iron fist", and the use of "populist punitiveness" as a strategy to gain the backing of an electorate deeply concerned by insecurity.

  16. EDUCATION AND CULTURE OF PEACE POLITICAL PARTIES IN CENTRAL AMERICA

    Directory of Open Access Journals (Sweden)

    Julio Alberto Acuña Martínez

    2015-07-01

    Full Text Available This research aims to identify in the normative documents of some political parties in Central America, which are in harmony with their political constitutions and international instruments, the provisions that promote education and culture of peace, and to assess its effectiveness. It is documentary and its analysis is based on deductive and comparative methods, it covers the period from 1984 to 2012. This work concludes that the legal and statutory bodies in the countries studied incorporate components of education and culture of effective peace for the past twenty years in which there has been alternation of power through elections.

  17. Environmental impacts during geothermal development: Some examples from Central America

    International Nuclear Information System (INIS)

    Goff, S.; Goff, F.

    1997-01-01

    The impacts of geothermal development projects are usually positive. However, without appropriate monitoring plans and mitigation actions firmly incorporated into the project planning process, there exists the potential for significant negative environmental impacts. The authors present five examples from Central America of environmental impacts associated with geothermal development activities. These brief case studies describe landslide hazards, waste brine disposal, hydrothermal explosions, and air quality issues. Improved Environmental Impact Assessments are needed to assist the developing nations of the region to judiciously address the environmental consequences associated with geothermal development

  18. Review of the genera of Conoderinae (Coleoptera, Curculionidae) from North America, Central America, and the Caribbean

    Science.gov (United States)

    Anzaldo, Salvatore S.

    2017-01-01

    Abstract The thirty-nine extant genera of Conoderinae known to occur in North America, Central America, and the Caribbean are reviewed based on external morphology. An identification key is provided along with diagnoses, distributions, species counts, and natural history information, when known, for each genus. Morphological character systems of importance for weevil classification are surveyed, potential relationships among the tribes and genera are discussed, and groups most in need of taxonomic and phylogenetic attention are identified. The following genera are transferred to new tribes: Acoptus LeConte, 1876 from the Lechriopini to the Othippiini (new placement) and the South American genus Hedycera Pascoe, 1870 from the Lechriopini to the Piazurini (new placement). Philides Champion, 1906 and Philinna Champion, 1906 are transferred from the Lechriopini to Conoderinae incertae sedis (new placement) although their placement as conoderines is uncertain. The species Copturomimus cinereus Heller, 1895 is designated as the type species of the genus Copturomimus Heller, 1895. PMID:28769729

  19. Review of the genera of Conoderinae (Coleoptera, Curculionidae from North America, Central America, and the Caribbean

    Directory of Open Access Journals (Sweden)

    Salvatore S. Anzaldo

    2017-07-01

    Full Text Available The thirty-nine extant genera of Conoderinae known to occur in North America, Central America, and the Caribbean are reviewed based on external morphology. An identification key is provided along with diagnoses, distributions, species counts, and natural history information, when known, for each genus. Morphological character systems of importance for weevil classification are surveyed, potential relationships among the tribes and genera are discussed, and groups most in need of taxonomic and phylogenetic attention are identified. The following genera are transferred to new tribes: Acoptus LeConte, 1876 from the Lechriopini to the Othippiini (new placement and the South American genus Hedycera Pascoe, 1870 from the Lechriopini to the Piazurini (new placement. Philides Champion, 1906 and Philinna Champion, 1906 are transferred from the Lechriopini to Conoderinae incertae sedis (new placement although their placement as conoderines is uncertain. The species Copturomimus cinereus Heller, 1895 is designated as the type species of the genus Copturomimus Heller, 1895.

  20. Implications of the Central America-Dominican Republic-Free Trade Agreement for the nutrition transition in Central America.

    Science.gov (United States)

    Hawkes, Corinna; Thow, Anne Marie

    2008-11-01

    To identify potential impacts of the Central America-Dominican Republic-Free Trade Agreement (CAFTA-DR) on food consumption patterns associated with the nutrition transition, obesity, and diet-related chronic diseases. Examination of CAFTA-DR agreement to identify measures that have the potential to affect food availability and retail prices. CAFTA-DR includes agreements on tariffs, tariff-rate quotas (TRQs), and sanitary and phytosanitary regulations with direct implications for the availability and prices of various foods. Agreements on investment, services, and intellectual property rights (IPR) are also relevant because they create a business climate more conducive to long-term investment by the transnational food industry. Trade liberalization under CAFTA-DR is likely to increase availability and lower relative prices of two food groups associated with the nutrition transition: meat and processed foods. These outcomes are expected to occur as the direct result of increased imports from the United States and increased production by U.S. companies based in Central America, and the indirect result of increased domestic meat production (due to increased availability of cheaper animal feed) and increased production of processed foods by domestic companies (due to a more competitive market environment). CAFTA-DR is likely to further the nutrition transition in Central America by increasing the consumption of meat; highly processed foods; and new, non-traditional foods. The public health community should be more aware of the implications of trade agreements for dietary health. Governments and related stakeholders should assess the coherence between changes fostered by specific trade agreements with national policies on diet and nutrition.

  1. Cuban Migration Trends and Their Impact on Central America Region

    Directory of Open Access Journals (Sweden)

    Charleene Cortez Sosa

    2017-06-01

    Full Text Available In recent years, the migration of Cuban population has taken new directions; this is mainly due to the migration policy flexibility adopted by the Cuban government and other Latin America governments, such as Ecuador, Grenada, Trinidad and Tobago, Dominican Republic, and Haiti, among others, by issuing visas in favorable conditions for the population. Although there are varied reasons to migrate, this population has traditionally migrated motivated by the United States Cuban Adjustment Act which grants administrative advantages for regularization; no other country of the continent offers this privilege. Due to their political exile condition, whoever arrives to the United States will easily have access to legal mechanisms for migrant regularization. Although there has been great work on migration in general terms, little has been addressed on the Cuban migration in the Central American region; possibly this is due to the difficulty to find quantitative information in this regard. The article aims to facilitate the understanding of migration in a context of flexibility and establishment of new relations between the Caribbean and Central America.

  2. Team Massachusetts & Central America Solar Decathlon 2015 Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kenneth [Western New England Univ., Springfield, MA (United States)

    2016-04-29

    Our team was Team MASSCA (Massachusetts and Central America), which was a partnership of Western New England University (WNE) located in Massachusetts USA, The Technological University of Panama (UTP), and Central American Technological University (UNITEC) of Honduras. Together we had a group of 6 faculty members and approximately 30 undergraduate students. Our house is ‘The EASI’ House, which stands for Efficient, Affordable, Solar Innovation. The EASI house is rectangular with two bedrooms and one bath, and offers a total square footage of 680. Based on competition estimates, The EASI house costs roughly $121,000. The EASI house has a 5kW solar system. Faculty and students from all three institutions were represented at the competition in Irvine California. Team MASSCA did well considering this was our first entry in the Solar Decathlon competition. Team MASSCA won the following awards: First Place – Affordability Contest Second Place – Energy Balance Contest. The competition provided a great experience for our students (and faculty as well). This competition provided leadership, endurance, and technical knowledge/skills for our students, and was the single most important hands-on experience during their undergraduate years. We are extremely pleased with the awards we received. At the same time we have learned from our efforts and would do better if we were to compete in the future. Furthermore, as a result of our team’s Inter-Americas collaborative effort, UTP and WNE have partnered to form Team PANAMASS (PANAma and MASSachusetts) and have developed The 3 SMART House for the inaugural Solar Decathlon Latin America & Caribbean competition held in Colombia.

  3. From transpressional to transtensional tectonics in Northern Central America controlled by Cocos - Caribbean subduction coupling change

    Science.gov (United States)

    Alonso-Henar, Jorge; Alvarez-Gomez, José Antonio; Jesús Martinez-Diaz, José

    2017-04-01

    The Central American Volcanic Arc (CAVA) is located at the western margin of the Caribbean plate, over the Chortís Block, spanning from Guatemala to Costa Rica. The CAVA is associated to the subduction of the Cocos plate under the Caribbean plate at the Middle America Trench. Our study is focused in the Salvadorian CAVA segment, which is tectonically characterized by the presence of the El Salvador Fault Zone (ESFZ), part of the western boundary of a major block forming the Caribbean plate (the Chortis Block). The structural evolution of the western boundary of the Chortis Block, particularly in the CAVA crossing El Salvador remains unknown. We have done a kinematic analysis from seismic and fault slip data and combined our results with a review of regional previous studies. This approach allowed us to constrain the tectonic evolution and the forces that control the deformation in northern Central America. Along the active volcanic arc we identified active transtensional deformation. On the other hand, we have identified two deformation phases in the back arc region: A first one of transpressional wrenching close to simple shearing (Miocene); and a second one characterized by almost E-W extension. Our results reveal a change from transpressional to transtensional shearing coeval with a migration of the volcanism towards the trench in Late Miocene times. This strain change could be related with a coupled to decoupled transition on the Cocos - Caribbean subduction interface, which could be related to a slab roll-back of the Cocos Plate beneath the Chortis Block. The combination of different degrees of coupling on the subduction interface, together with a constant relative eastward drift of the Caribbean Plate, control the deformation style along the western boundary of the Chortis Block.

  4. Performance of Early Warning Systems on Landslides in Central America

    Science.gov (United States)

    Strauch, W.; Devoli, G.

    2012-04-01

    We performed a reconnaissance about Early Warning Systems (EWS) on Landslides (EWSL) in the countries of Central America. The advance of the EWSL began in the 1990-ies and accelerated dramatically after the regional disaster provoked by Hurricane Mitch in 1998. In the last decade, Early Warning Systems were intensely promoted by national and international development programs aimed on disaster prevention. Early Warning on landslides is more complicated than for other geological phenomena. But, we found information on more than 30 EWSL in the region. In practice, for example in planning, implementation and evaluation of development projects, it is often not clearly defined what exactly is an Early Warning System. Only few of the systems can be classified as true EWSL that means 1) being directly and solely aimed at persons living in the well-defined areas of greatest risk and 2) focusing their work on saving lives before the phenomenon impacts. There is little written information about the work of the EWSL after the initial phase. Even, there are no statistics whether they issued warnings, if the warnings were successful, how many people were evacuated, if there were few false alerts, etc.. Actually, we did not find a single report on a successful landslide warning issued by an EWSL. The lack of information is often due to the fact that communitarian EWSL are considered local structures and do not have a clearly defined position in the governmental hierarchy; there is little oversight and no qualified support and long-term support. The EWSL suffer from severe problems as lack of funding on the long term, low technical level, and insufficient support from central institutions. Often the EWSL are implemented by NGÓs with funding from international agencies, but leave the project alone after the initial phase. In many cases, the hope of the local people to get some protection against the landslide hazard is not really fulfilled. There is one case, where an EWSL with a

  5. Evolution of the Earthquake Catalog in Central America

    Science.gov (United States)

    Rojas, W.; Camacho, E. I.; Marroquín, G.; Molina, E.; Talavera, E.; Benito, M. B.; Lindholm, C.

    2013-05-01

    Central America (CA) is known as a seismically active region in which several historic destructive earthquakes have occurred. This fact has promoved the development of seismic hazard studies that provide necessary estimates for decision making and risk assessment efforts, requiring a complete and standardized seismic catalog. With this aim, several authors have contributed to the study of the historical seismicity of Central America (e.g. Grases, Feldaman; White y Harlow, 1993; White et al. 2004; Ambraseys y Adams, 2001; Peraldo y Montero, 1999), who complied historical data. A first catalogue was developed by Rojas (1993) that comprises the 1522 to 1993 period. This information was integrated in 2007, together with data from the International Seismological Centre (CASC) and the national catalogs of CA countries in a new regional catalogue. Since 2007 a continuous effort has been done in order to complete and update this CA earthquake catalog. In particular, two workshops were held in 2008 and 2011 in the Universidad Politécnica de Madrid (Spain), joining experts from the different CA countries who worked each one in its own catalogue covering the entire region and the border with northwestern Colombia and southern Mexico. These national catalogues were later integrated in a common regional catalogue in SEISAN format. At this aim it was necessary to solve some problems, like to avoid duplicity of events, specially close to the boundaries, to consider the different scales of magnitude adopted by different countries, to take into account the completeness by the different national networks, etc. Some solutions were adopted for obtaining a homogenized catalogue to Mw, containing historical and instrumental events with Mw > 3.5 from 1522 up to 2011. The catalogue updated to December 2007 was the basis for the first regional hazard study carried out by Benito et al., (2011) as part of the collaborative RESIS II project under coordination of NORSAR. The ones updated to

  6. Renewable energies. A challenge and an opportunity for Central America; Energias renovables. Un reto y una oportunidad para America Central

    Energy Technology Data Exchange (ETDEWEB)

    Guevara, Leo; Castro S, Rene [Instituto Centroamericano de Administracion de Empresas (INCAE) (Costa Rica)

    2007-07-15

    There are analyzed in this working paper the following aspects: the Central America countries and their relations with the regional energy potencies -Mexico and Venezuela- and the impact they have in the energy supply. There are also explore the following aspects: the San Jose Agreement linked to the fossil fuels supply, the emerging scope boosted by Brazil and Colombia regarding to the alternative fuels. [Spanish] Este trabajo analiza los paises centroamericanos y sus relaciones con las potencias energeticas regionales como Mexico y Venezuela, y como estas impactan el suministro de energia en la region. Tambien se exploran mecanismos como el Pacto de San Jose, ligado al suministro de combustibles fosiles y las oportunidades emergentes impulsadas por Brasil y Colombia con combustibles alternativos.

  7. Mantle transition zone beneath the central Tien Shan: Lithospheric delamination and mantle plumes

    Science.gov (United States)

    Kosarev, Grigoriy; Oreshin, Sergey; Vinnik, Lev; Makeyeva, Larissa

    2018-01-01

    We investigate structure of the mantle transition zone (MTZ) under the central Tien Shan in central Asia by using recordings of seismograph stations in Kyrgyzstan, Kazakhstan and adjacent northern China. We apply P-wave receiver functions techniques and evaluate the differential time between the arrivals of seismic phases that are formed by P to SV mode conversion at the 410-km and 660-km seismic boundaries. The differential time is sensitive to the thickness of the MTZ and insensitive to volumetric velocity anomalies above the 410-km boundary. Under part of the southern central Tien Shan with the lowest S wave velocity in the uppermost mantle and the largest thickness of the crust, the thickness of the MTZ increases by 15-20 km relative to the ambient mantle and the reference model IASP91. The increased thickness is a likely effect of low (about - 150 K) temperature. This anomaly is indicative of delamination and sinking of the mantle lithosphere. The low temperature in the MTZ might also be a relic of subduction of the oceanic lithosphere in the Paleozoic, but this scenario requires strong coupling and coherence between structures in the MTZ and in the lithosphere during plate motions in the last 300 Myr. Our data reveal a reduction of thickness of the MTZ of 10-15 km under the Fergana basin, in the neighborhood of the region of small-scale basaltic volcanism at the time near the Cretaceous-Paleogene boundary. The reduced thickness of the MTZ is the effect of a depressed 410-km discontinuity, similar to that found in many hotspots. This depression suggests a positive temperature anomaly of about 100-150 K, consistent with the presence of a thermal mantle plume. A similar depression on the 410-km discontinuity is found underneath the Tarim basin.

  8. Magmatic activity beneath the quiescent Three Sisters volcanic center, central Oregon Cascade Range, USA

    Science.gov (United States)

    Wicks, Charles W.; Dzurisin, Daniel; Ingebritsen, Steven; Thatcher, Wayne; Lu, Zhong; Iverson, Justin

    2002-04-01

    Images from satellite interferometric synthetic aperture radar (InSAR) reveal uplift of a broad ~10 km by 20 km area in the Three Sisters volcanic center of the central Oregon Cascade Range, ~130 km south of Mt. St. Helens. The last eruption in the volcanic center occurred ~1500 years ago. Multiple satellite images from 1992 through 2000 indicate that most if not all of ~100 mm of observed uplift occurred between September 1998 and October 2000. Geochemical (water chemistry) anomalies, first noted during 1990, coincide with the area of uplift and suggest the existence of a crustal magma reservoir prior to the uplift. We interpret the uplift as inflation caused by an ongoing episode of magma intrusion at a depth of ~6.5 km.

  9. Bedrock topography beneath uppermost part of Aletsch glacier, Central Swiss Alps, revealed from cosmic-ray muon radiography

    Science.gov (United States)

    Nishiyama, Ryuichi; Ariga, Akitaka; Ariga, Tomoko; Käser, Samuel; Lechmann, Alessandro; Mair, David; Scampoli, Paola; Vladymyrov, Mykhailo; Ereditato, Antonio; Schlunegger, Fritz

    2017-04-01

    In mountainous landscapes such as the Central Alps of Europe, the bedrock topography is one of the most interesting subjects of study since it separates the geological substratum (bedrock) from the overlying unconsolidated units (ice). The geometry of the bedrock topography puts a tight constraint on the erosional mechanism of glaciers. In previous studies, it has been inferred mainly from landscapes where glaciers have disappeared after the termination of the last glacial epoch. However, the number of studies with a focus on the structure beneath active glaciers is limited, because existing exploration methods have limitation in resolution and mobility. The Eiger-μ project proposes a new technology, called muon radiography, to investigate the bedrock geometry beneath active glaciers. The muon radiography is a recent technique that relies on the high penetration power of muon components in natural cosmic rays. Specifically, one can resolve the internal density profile of a gigantic object by measuring the attenuation rate of the intensity of muons after passing through it, as in medical X-ray diagnostic. This technique has been applied to many fields such as volcano monitoring (eg. Ambrosino et al., 2015; Jourde et al., 2016; Nishiyama et al., 2016), detection of seismic faults (eg. Tanaka et al., 2011), inspection inside nuclear reactors, etc. The first feasibility test of the Eiger-μ project has been performed at Jungfrau region, Central Swiss Alps, Switzerland. We installed cosmic-ray detectors consisting of emulsion films at three sites along the Jungfrau railway tunnel facing Aletsch glacier (Jungfraufirn). The detectors stayed 47 days in the tunnel and recorded the tracks of muons which passed through the glacier and bedrock (thickness is about 100 m). Successively the films were chemically developed and scanned at University of Bern with microscopes originally developed for the analysis of physics experiments on neutrino oscillation. The analysis of muon

  10. Diurnal variations in water vapor over Central and South America

    Science.gov (United States)

    Meza, Amalia; Mendoza, Luciano; Clara, Bianchi

    2017-04-01

    Diurnal variations in atmospheric integrated water vapor (IWV) are studied employing IWV estimates, with a 30 minutes sampling rate, derived from Global Navigation Satellite Systems (GNSS) observations during the period 2007-2013. The analysis was performed in 70 GNSS tracking sites (GPS + GLONASS) belonging to Central and South America, which have more than 5 years of data. The selected area involves different climate types, from polar to tropical, and diverse relieves, therefore the patterns of IWV diurnal variations are very different for each station. There are many processes that could induce diurnal variations in atmospheric water vapor (Dai et al, 1999 a,b), the most relevant causes are: surface evapotranspiration, atmospheric large-scale vertical motion, atmospheric low-level moisture convergence and precipitation and vertical mixing (which affects the vertical distribution of water vapor but does not affect the IWV). Firstly, our work study the main characteristics of the IWV diurnal cycle (and for surface temperature, T) obtained for all stations together, using Principal Component Analysis (PCA). First and second PCA modes highlight the global main behaviors of IWV variability for all stations. The first mode on IWV represent the 70% of the variability and could be related to the surface evapotranspiration, while the second mode (27 % of the variability) is practically in counter phase to T variability (its first mode represent the 97% of the variability), therefore this mode could be related to breeze regime. Then, every station is separately analyzed and seasonal and local variations (relative to the relives) are detected, these results spotlight, among other characteristics, the sea and mountain breeze regime. This presentation shows the first analysis of IWV diurnal cycle performed over Central and South America and another original characteristic is PCA technique employed to infer the results. Reference: Dai, A., K. E. Trenberth, and T. R. Karl

  11. Patterns of illness in travelers visiting Mexico and Central America: the GeoSentinel experience

    NARCIS (Netherlands)

    Flores-Figueroa, Jose; Okhuysen, Pablo C.; von Sonnenburg, Frank; Dupont, Herbert L.; Libman, Michael D.; Keystone, Jay S.; Hale, Devon C.; Burchard, Gerd; Han, Pauline V.; Wilder-Smith, Annelies; Freedman, David O.; Kain, Kevin C.; Gelman, Stephanie S.; Ward, Brian; Dick Maclean, J.; Jean Haulman, N.; Roesel, David; Jong, Elaine C.; Schwartz, Eli; Stauffer, William M.; Walker, Patricia F.; Kozarsky, Phyllis E.; Franco-Paredes, Carlos; Pandey, Prativa; Murphy, Holly; Loutan, Louis; Chappuis, François; McCarthy, Anne; Connor, Bradley A.; Chen, Lin H.; Wilson, Mary E.; Lynch, Michael W.; Licitra, Carmelo; Crespo, Antonio; Caumes, Eric; Pérignon, Alice; de Vries, Peter J.; Gadroen, Kartini; Nutman, Thomas B.; Klion, Amy D.; Hynes, Noreen; Bradley Sack, R.; McKenzie, Robin; Field, Vanessa; Gurtman, Alejandra; Coyle, Christina M.; Wittner, Murray; Parola, Philippe; Simon, Fabrice; Delmont, Jean; Leder, Karin; Torresi, Joseph; Brown, Graham; Jensenius, Mogens; Wang, Andy; MacDonald, Susan; López-Vélez, Rogelio; Antonio Perez Molina, Jose; Cahill, John D.; McKinley, George; Schlagenhauf, Patricia; Weber, Rainer; Steffen, Robert; Shaw, Marc; Hern, Annemarie; Perret, Cecilia; Valdivieso, Francisca; Valdez, Luis; Siu, Hugo; Carosi, Giampiero; Castelli, Francesco; Tachikawa, Natsuo; Kurai, Hanako; Sagara, Hiroko; Kass, Robert; Barnett, Elizabeth D.; McLellan, Susan; Holtom, Paul; Goad, Jeff; Anglim, Anne; Hagmann, Stefan; Henry, Michael; Miller, Andy O.; Ansdell, Vernon; Kato, Yasuyuki; Borwein, Sarah; Anderson, Nicole; Batchelor, Trish; Meisch, Dominique; Gkrania-Klotsas, Effrossyni; Doyle, Patrick; Ghesquiere, Wayne; Piper Jenks, Nancy; Kerr, Christine; Lian Lim, Poh; Piyaphanee, Watcharapong; Silachamroon, Udomsak; Mendelson, Marc; Vincent, Peter; Africa, South; Virk, Abinash; Sia, Irene

    2011-01-01

    Mexico and Central America are important travel destinations for North American and European travelers. There is limited information on regional differences in travel related morbidity. We describe the morbidity among 4779 ill travelers returned from Mexico and Central America who were evaluated at

  12. Evaluating regional differences in macroinvertebrate communities from forested depressional wetlands across eastern and central North America

    Science.gov (United States)

    Darold P. Batzer; Susan E. Dietz-Brantley; Barbara E. Taylor; Adrienne E. DeBiase

    2005-01-01

    Forested depressional wetlands are an important seasonal wetland type across eastern and central North America. Macroinvertebrates are crucial ecosystem components of most forested depressional wetlands, but community compositions can vary widely across the region. We evaluated variation in macroinvertebrate faunas across eastern and central North America using 5...

  13. 7 CFR 319.56-25 - Papayas from Central America and Brazil.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Papayas from Central America and Brazil. 319.56-25... § 319.56-25 Papayas from Central America and Brazil. The Solo type of papaya may be imported into the... shipment to the United States in one of the following locations: (1) Brazil: State of Espirito Santo; all...

  14. 75 FR 50695 - Dominican Republic-Central America-United States Free Trade Agreement

    Science.gov (United States)

    2010-08-17

    ...-AB84) Dominican Republic--Central America--United States Free Trade Agreement AGENCIES: Customs and... the Dominican Republic--Central America--United States Free Trade Agreement. DATES: Final rule... States Free Trade Agreement (``CAFTA-DR'' or ``Agreement''). The provisions of the CAFTA-DR were adopted...

  15. Seismic anisotropy and mantle dynamics beneath the central and western United States

    Science.gov (United States)

    Yang, Bin

    Various tectonic features and the recent availability of high-quality broadband seismic data from the USArray and other seismic stations in the central and western United States (CWUS) provide a distinct opportunity to test different anisotropy-forming mechanisms. For the first part of the study, a total of 4138 pairs of well-defined shear wave splitting (SWS) parameters observed at 445 stations on the northern Great Plains show systematic spatial variations of anisotropic characteristics. Azimuthally invariant fast orientations subparallel to the absolute plate motion (APM) direction are observed at most of the stations on the Superior Craton and the southern Yavapai province, indicating that a single layer of anisotropy with a horizontal axis of symmetry is sufficient to explain the anisotropic structure. Based on the splitting measurements and previous results from seismic tomography and geodynamic modeling, we propose a model involving deflecting of asthenosphere flow by the bottom of the lithosphere and channeling flow by a zone of thinned lithosphere approximately along the northern boundary of the Yavapai province. The second part of the study created an up-to-date SWS database for CWUS in the area of 125° W to 90° W, 26° N to 52° N to upgrade a previous database [Liu et al., 2014]. A total of 7452 pairs of high-quality measurements recorded by 1202 digital broadband seismic stations (both permanent and portable seismic networks) over the period of 1989-2014 is obtained. The current version includes 23448 pairs of well-defined splitting parameters in three phases, i.e. PKS, SKKS and SKS. The dissertation is a combination of two journal papers published in 2014 and 2016, respectively.

  16. Common characteristics of paired volcanoes in northern Central America

    Science.gov (United States)

    Halsor, Sid P.; Rose, William I.

    1988-05-01

    Four pairs of active volcanoes along the northern Central American volcanic front have erupted basalt-andesite magmas that show consistent intrapair behavioral and compositional differences. These differences are found in records of volcanic activity and complete major and minor element data on over 200 samples. From northwest to southeast along the volcanic front the four volcano pairs are Cerro Quemado-Santa María, Tolimán-Atitlán, Acatenango-Fuego, and Santa Ana-Izalco. The volcano pair relations help explain compositional differences, apart from those reflecting variation in crustal thickness of about 15 km along the volcanic front, providing insight into across-arc variations and closely spaced subvolcanic plumbing systems. Intravolcano pair spacing is less than 5 km compared with an average intervolcano spacing of 25 km along the entire volcanic front. Within each volcano pair, the seaward volcano has had more frequent historic activity, erupting magmas that are generally more mafic, lower in large ion lithophile elements and higher in Na2O/K2O than magmas erupted from its landward counterpart. Each paired volcano site lies in close proximity to a rhyolitic caldera, situated north or northeast of the volcano pair. However, rare earth element data at the Tolimán-Atitlán volcano pair imply that mixing between caldera rhyolite and the mafic magma of the paired volcanoes does not occur. Petrographie, isotopic, and other geochemical data from the Tolimán-Atitlán volcano pair suggest that separate but contemporaneous magma bodies beneath each volcano evolve and pass through the crust at different rates. Atitlán magmas are processed through the crust more efficiently and with greater frequency than Tollman magmas, which undergo longer periods of stagnation interrupted by mafic injection and rapid eruption. This relation appears to hold at the other paired volcano sites and is further evidence that closely spaced volcanoes, with similar subcrustal magma

  17. Asthenospheric percolation of alkaline melts beneath the St. Paul region (Central Atlantic Ocean)

    Science.gov (United States)

    Brunelli, Daniele; Seyler, Monique

    2010-01-01

    Two peridotite suites collected by submersible in the equatorial Atlantic Ocean (Hekinian et al., 2000) were studied for textures, modes, and in situ major and trace element compositions in pyroxenes. Dive SP12 runs along the immersed flank of the St. Peter and Paul Rocks islets where amphibole-bearing, ultramafic mylonites enriched in alkalies and incompatible elements are exposed (Roden et al., 1984), whereas dive SP03 sampled a small intra-transform spreading centre situated about 370 km east of the St. Peter and Paul Rocks. Both suites are characterized by undeformed, coarse-grained granular textures typical of abyssal peridotites, derived from residual mantle after ˜ 15% melting of a DMM source, starting in the garnet stability field. Trace element modelling, textures and lack of mineral zoning indicate that the residual peridotites were percolated, reacted and refertilized by ˜ 2.6% partially aggregated melts in the uppermost level of the melting region. This relatively large amount of refertilization is in agreement with the cold and thick lithosphere inferred by previous studies. Freezing of trapped melts occurred as the peridotite entered the conductive layer, resulting in late-stage crystallization of olivine, clinopyroxene, spinel, ± plagioclase. Chondrite-normalized REE patterns in clinopyroxenes from SP03 indicate that they last equilibrated with (ultra-) depleted partial melts. In contrast, REE concentrations in clinopyroxenes from SP12 display U and S shaped LREE-enriched patterns and the calculated compositions of the impregnating melts span the compositional range of the regional basalts, which vary from normal MORB to alkali basalt sometimes modified by chromatographic fractionation with no, or very limited, mineral reaction. Thus the mylonitic band forming the St. Peter and St. Paul Rocks ridge is not a fragment of subcontinental lithospheric mantle left behind during the opening of the Central Atlantic, nor the source of the alkaline basalts

  18. Branched GDGT distributions in lakes from Mexico and Central America

    Science.gov (United States)

    Lei, A.; Werne, J. P.; Correa-Metrio, A.; Pérez, L.; Caballero, M.

    2017-12-01

    The potential to use bacterial derived branched glycerol dialkyl glycerol tetraethers (brGDGTs) to reconstruct mean annual air temperatures from soils sparked significant interest in the terrestrial paleoclimate community, where a high-fidelity paleotemperature proxy is desperately needed. While the source of brGDGTs remains unknown (but are potentially attributed to the highly diverse phylum Acidobacteria), much evidence points to the potential for these bacteria to live not only in the terrestrial environment but also in lake water and sediments as well. Though the application of brGDGTs to lacustrine reconstructions is promising, the initial applications of soil-based MBT/CBT proxy to lacustrine sediments typically resulted in lower temperatures than were reasonable, likely due to additions from lacustrine bacterial brGDGTs. Here, we present data from a suite of >100 lakes in Mexico and Central America, producing a regional core-top calibration different from those developed in other regions. Results indicate a significant role for regional differences in controlling the brGDGTs distribution, likely due to different brGDGT-producing microbial communities thriving under varying environmental conditions. Rigorous development of brGDGT based proxies will improve our understanding of the source and applicability of these biomarkers, and increase confidence in the accuracy of paleotemperature reconstructions to numerous lacustrine records in the region.

  19. Managing weather and climate risks to agriculture in North America, Central America and the Caribbean

    Directory of Open Access Journals (Sweden)

    Harlan D. Shannon

    2015-12-01

    Full Text Available In recent decades, numerous weather- and climate-related natural disasters have impacted North America, Central America, and the Caribbean, repeatedly demonstrating how vulnerable local agriculture is to extreme episodic events. Given this recent history, and expectations that the frequency and intensity of some episodic events will increase with climate change, it is becoming increasingly important for farmers to proactively manage weather and climate risks to agriculture to protect their livelihoods. Some farmers in this region already apply various strategies to help reduce weather and climate risks and uncertainties, including farming in multiple locations, diversifying crops and varieties, seeking alternative sources of income, and purchasing crop insurance. Such efforts often help farmers maintain a more stable income while also protecting and preserving the productivity of the land. Other farmers, however, have failed to implement basic risk management strategies despite the clear benefits. Reasons for these failures can be attributed to inadequate farmer education and training, a lack of tools to help facilitate the practical application of risk management concepts, and poor communications between the agrometeorological and farming communities. The agrometeorological community can help overcome these obstacles by building upon existing efforts that have successfully educated farmers about weather and climate risks to agriculture and have equipped farmers with the data, tools, and applications necessary to manage these risks. Farmer input is critical to preparing effective educational and training materials and developing user-friendly risk management tools. The agrometeorological community should solicit input from farmers regularly to ensure that farmers are obtaining the information necessary to effectively manage weather and climate risks to agriculture.

  20. Federacion de Universidades Privadas de America Central y Panama: Boletin Estadistico (Federation of Private Universities of Central America and Panama: Statistical Bulletin).

    Science.gov (United States)

    Serrano, Jorge A.

    This statistical bulletin provides details on the universities belonging to the Federation of Private Universities of Central America and Panama (FUPAC): Central American University, Rafael Landivar University, Saint John's College, University of Santa Maria La Antigua, Jose Simeon Canas University, Doctor Mariano Galvez University, and the…

  1. Mapping Mangrove Density from Rapideye Data in Central America

    Science.gov (United States)

    Son, Nguyen-Thanh; Chen, Chi-Farn; Chen, Cheng-Ru

    2017-06-01

    Mangrove forests provide a wide range of socioeconomic and ecological services for coastal communities. Extensive aquaculture development of mangrove waters in many developing countries has constantly ignored services of mangrove ecosystems, leading to unintended environmental consequences. Monitoring the current status and distribution of mangrove forests is deemed important for evaluating forest management strategies. This study aims to delineate the density distribution of mangrove forests in the Gulf of Fonseca, Central America with Rapideye data using the support vector machines (SVM). The data collected in 2012 for density classification of mangrove forests were processed based on four different band combination schemes: scheme-1 (bands 1-3, 5 excluding the red-edge band 4), scheme-2 (bands 1-5), scheme-3 (bands 1-3, 5 incorporating with the normalized difference vegetation index, NDVI), and scheme-4 (bands 1-3, 5 incorporating with the normalized difference red-edge index, NDRI). We also hypothesized if the obvious contribution of Rapideye red-edge band could improve the classification results. Three main steps of data processing were employed: (1), data pre-processing, (2) image classification, and (3) accuracy assessment to evaluate the contribution of red-edge band in terms of the accuracy of classification results across these four schemes. The classification maps compared with the ground reference data indicated the slightly higher accuracy level observed for schemes 2 and 4. The overall accuracies and Kappa coefficients were 97% and 0.95 for scheme-2 and 96.9% and 0.95 for scheme-4, respectively.

  2. Seismic anisotropy beneath the greater region of the central External Dinarides from observations of SKS-splitting

    Science.gov (United States)

    Subašić, Senad; Prevolnik, Snježan; Herak, Marijan

    2016-04-01

    Measurements of SKS wave splitting beneath greater region of the central External Dinarides (Dalmatia, Croatia) were made in order to investigate seismic anisotropy in the upper mantle and the lithosphere. The area is located in the broad and complex Africa-Eurasia convergent plate boundary zone, where Adriatic microplate interacts with the External Dinarides. We used broadband recordings (more than 3500 analyzed seismograms) from 10 permanent stations situated along the Croatian coastal region. The splitting parameters - fast axis and delay time - were measured using the Silver and Chan method. Seismic anisotropy was observed on all stations. Fast axis directions are fairly uniformly oriented approximately in the NE-SW to NNE-SSW direction, thus perpendicularly to the strike of the Dinarides. Average delay times range between 0.7 and 1.0 seconds. Slight counter-clockwise rotation in average fast axis directions was observed for the stations in the northern part of the studied area, as well as a small increase in average delay times, with respect to the stations in the southern part. We also observed differences in splitting parameters for back-azimuths sampling different tectonic units (Euroasian plate and Adria), however, due to poor back-azimuthal coverage and limited dataset, more measurements have to be made to enable reliable validation of this observation. Fast axis directions coincide with the direction of the maximum tectonic pressure in the crust and with observed fast directions of P-waves in the crust, which might imply a significant crustal component of measured anisotropy, alongside the component resulting from the upper mantle structures.

  3. Agricultural drought assessment using remotely sensed data in Central America

    Science.gov (United States)

    Nguyen, S. T.; Chen, C. F.; Chen, C. R.

    2017-12-01

    Central America is one of the world's regions most vulnerable to negative effects of agricultural drought due to impacts of climate change. Famers in the region have been confronting risks of crop damages and production losses due to intense droughts throughout the growing seasons. Drought information is thus deemed vital for policymakers to assess their crop management strategies in tackling issues of food insecurity in the region. This study aimed to delineate drought-prone areas associated with cropped areas from eight-day MODIS data in 2016 using the commonly used temperature dryness vegetation index (TVDI), calculated based on the land surface temperature (LST) and enhanced vegetation index (EVI) data. The advantages of MODIS data for agricultural drought monitoring at a national/regional scale are that it has the spatial resolution (500 m-1 km) and relatively high temporal resolution of eight days, but the data are often contaminated by clouds. Detecting and reconstructing the data under cloud-affected areas are generally a challenging task without any robust methods up to date. In this study, we reconstructed the eight-day MODIS EVI and LST data for agricultural drought assessment using machine-learning approaches. The reconstructed data were then used for drought assessment. The TVDI results verified with the soil moisture active passive (SMAP) data showed that the correlation coefficient values (r) obtained for the apante season (December-March) were between -0.4 to -0.8, while the values for the primera season (April-August) and postrera season (September-November) were in ranges of 0 to -0.6 and -0.2 to -0.7, respectively. The larger area of very dry soil moisture was generally observed during the dry season (December-April) and declined in the rainy season (May-November). The cropping areas affected by severe and moderate droughts observed for the primera season were respectively 11,846 km2 and 60,557 km2, while the values for the postera season were 14

  4. Alliances for Chagas elimination in Central America | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Public Health Implications of Alcohol Industry Corporate Social Responsibility Programs (Latin America). Researchers are raising growing concerns over the impact of corporate social responsibility (CSR) programs in the alcohol industry. View morePublic Health Implications of Alcohol Industry Corporate Social ...

  5. Source mechanism of a very-long-period event at Mt Ontake, central Japan: Response of a hydrothermal system to magma intrusion beneath the summit

    Science.gov (United States)

    Nakamichi, Haruhisa; Kumagai, Hiroyuki; Nakano, Masaru; Okubo, Makoto; Kimata, Fumiaki; Ito, Yoshihiro; Obara, Kazushige

    2009-11-01

    A very-long-period (VLP) volcanic event, which occurred on 25 January 2007 beneath Mt Ontake, central Japan, was recorded by nearby broadband seismometers as well as the Japanese nationwide Hi-net and F-net seismic networks. The VLP waveforms show a pulse-like shape with a duration of approximately 1 min. The VLP event was accompanied by a burst sequence of long-period (LP) events. We carried out waveform inversion to determine the source mechanism and location of the VLP event. Our analysis indicates volumetric changes in an inclined crack (seismic moment of 10 14 Nm) at the VLP source, which is located at 0.6 km above sea level beneath the summit of Mt Ontake and above dikes determined from GPS data. The source-time functions of the VLP event showed a pulse-like triangular shape, indicating inflation followed by deflation of the crack at the source. We interpreted the result of the waveform inversion as follows. Gases released from the intruded magma heated an aquifer system beneath the summit of Mt Ontake. A break of unstable superheated water in a hydrothermal crack in the system caused vaporization of water and associated crack inflation, which was followed by discharge of steam from the crack resulting in its collapse. These processes caused the VLP event, which may have been a precursor of a small phreatic eruption that occurred in late March 2007.

  6. Protecting The Homeland By Efficient Phase 0 Operations In The Caribbean, Central, And South America

    Science.gov (United States)

    2014-04-01

    Ministry of Health, Ministry of Defense, Ministry of Education , non-governmental organizations, bilingual schools and a variety of community members...Per the guidance provided in Military Medical Ethics, “military exercises specifically in Latin America were to (1) improve readiness of armed...Strengthening regional and U.S. security in the Caribbean, Central, and South America requires active engagement through exercises and educational

  7. Health outcomes among HIV-positive Latinos initiating antiretroviral therapy in North America versus Central and South America

    Science.gov (United States)

    Cesar, Carina; Koethe, John R; Giganti, Mark J; Rebeiro, Peter; Althoff, Keri N; Napravnik, Sonia; Mayor, Angel; Grinsztejn, Beatriz; Wolff, Marcelo; Padgett, Denis; Sierra-Madero, Juan; Gotuzzo, Eduardo; Sterling, Timothy R; Willig, James; Levison, Julie; Kitahata, Mari; Rodriguez-Barradas, Maria C; Moore, Richard D; McGowan, Catherine; Shepherd, Bryan E; Cahn, Pedro

    2016-01-01

    Introduction Latinos living with HIV in the Americas share a common ethnic and cultural heritage. In North America, Latinos have a relatively high rate of new HIV infections but lower rates of engagement at all stages of the care continuum, whereas in Latin America antiretroviral therapy (ART) services continue to expand to meet treatment needs. In this analysis, we compare HIV treatment outcomes between Latinos receiving ART in North America versus Latin America. Methods HIV-positive adults initiating ART at Caribbean, Central and South America Network for HIV (CCASAnet) sites were compared to Latino patients (based on country of origin or ethnic identity) starting treatment at North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) sites in the United States and Canada between 2000 and 2011. Cox proportional hazards models compared mortality, treatment interruption, antiretroviral regimen change, virologic failure and loss to follow-up between cohorts. Results The study included 8400 CCASAnet and 2786 NA-ACCORD patients initiating ART. CCASAnet patients were younger (median 35 vs. 37 years), more likely to be female (27% vs. 20%) and had lower nadir CD4 count (median 148 vs. 195 cells/µL, p<0.001 for all). In multivariable analyses, CCASAnet patients had a higher risk of mortality after ART initiation (adjusted hazard ratio (AHR) 1.61; 95% confidence interval (CI): 1.32 to 1.96), particularly during the first year, but a lower hazard of treatment interruption (AHR: 0.46; 95% CI: 0.42 to 0.50), change to second-line ART (AHR: 0.56; 95% CI: 0.51 to 0.62) and virologic failure (AHR: 0.52; 95% CI: 0.48 to 0.57). Conclusions HIV-positive Latinos initiating ART in Latin America have greater continuity of treatment but are at higher risk of death than Latinos in North America. Factors underlying these differences, such as HIV testing, linkage and access to care, warrant further investigation. PMID:26996992

  8. Neurocysticercosos in South-Central America and the Indian Subcontinent: a comparative evaluation

    Directory of Open Access Journals (Sweden)

    Gagandeep Singh

    1997-09-01

    Full Text Available Neurocysticercosis is an important public health problem in South-Central America and South Asia. A review of the differences in epidemiological and clinical attributes of cysticercosis and taeniasis in South Central America and India, respectively, is undertaken in the present communication. Intestinal taeniasis is hyperendemic in several American countries. In comparison, the prevalence of Taenia solium infestation is lower in India. The clinical manifestations in several American neurocysticercosis series comprise epilepsy, intracranial hypertension and meningeal - racemose cysticercosis, in roughly equal proportions. An overwhelming majority of the Indian subjects present with seizures. The commonest pathological substrate of the disorder in Indian patients is the solitary parenchymal degenerating cyst. The reasons for the predominance of solitary forms in India, and of multilesional forms in South Central America are discussed. The magnitude of Taenia solium infestation and the frequency of pork consumption in a given population appear to influence the quantum of cyst load in affected individuals.

  9. Linking social exclusion and violence in Central America | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2015-12-08

    Dec 8, 2015 ... ​An IDRC-supported study suggests that social exclusion, rather than poverty or income inequality, is the main underlying factor influencing Central American cities' vulnerability to violence. Researchers at the Latin American Faculty of Social Sciences (FLACSO) and American University observed that ...

  10. Education and commitment: Jesuit universities in Central America

    Directory of Open Access Journals (Sweden)

    Francisco Javier Gómez Díez

    2017-04-01

    Full Text Available An analysis of how Central American Jesuit Universities have defined their mission, with a particular focus on the public declarations of their leading figures. The aim is to explain why this mission contradicts the objectives initially established by these universities, while pointing out the limits and contradictions involved.

  11. High level of molecular and phenotypic biodiversity in Jatropha curcas from Central America compared to Africa, Asia and South America.

    Science.gov (United States)

    Montes Osorio, Luis Rodolfo; Torres Salvador, Andres Fransisco; Jongschaap, Raymond Elmar Etienne; Azurdia Perez, Cesar Augusto; Berduo Sandoval, Julio Ernesto; Trindade, Luisa Miguel; Visser, Richard Gerardus Franciscus; van Loo, Eibertus Nicolaas

    2014-03-25

    The main bottleneck to elevate jatropha (Jatropha curcas L.) from a wild species to a profitable biodiesel crop is the low genetic and phenotypic variation found in different regions of the world, hampering efficient plant breeding for productivity traits. In this study, 182 accessions from Asia (91), Africa (35), South America (9) and Central America (47) were evaluated at genetic and phenotypic level to find genetic variation and important traits for oilseed production. Genetic variation was assessed with SSR (Simple Sequence Repeat), TRAP (Target Region Amplification Polymorphism) and AFLP (Amplified fragment length polymorphism) techniques. Phenotypic variation included seed morphological characteristics, seed oil content and fatty acid composition and early growth traits. Jaccard's similarity and cluster analysis by UPGM (Unweighted Paired Group Method) with arithmetic mean and PCA (Principle Component Analysis) indicated higher variability in Central American accessions compared to Asian, African and South American accessions. Polymorphism Information Content (PIC) values ranged from 0 to 0.65. In the set of Central American accessions. PIC values were higher than in other regions. Accessions from the Central American population contain alleles that were not found in the accessions from other populations. Analysis of Molecular Variance (AMOVA; P Central American accessions showed very large genetic variation as assessed by DNA-marker variation compared to accessions from other regions. Central American accessions also showed the highest phenotypic variation and should be considered as the most important source for plant breeding. Some variation in early growth traits was found within a group of accessions from Asia and Africa, while these accessions did not differ in a single DNA-marker, possibly indicating epigenetic variation.

  12. High level of molecular and phenotypic biodiversity in Jatropha curcas from Central America compared to Africa, Asia and South America

    Science.gov (United States)

    2014-01-01

    Background The main bottleneck to elevate jatropha (Jatropha curcas L.) from a wild species to a profitable biodiesel crop is the low genetic and phenotypic variation found in different regions of the world, hampering efficient plant breeding for productivity traits. In this study, 182 accessions from Asia (91), Africa (35), South America (9) and Central America (47) were evaluated at genetic and phenotypic level to find genetic variation and important traits for oilseed production. Results Genetic variation was assessed with SSR (Simple Sequence Repeat), TRAP (Target Region Amplification Polymorphism) and AFLP (Amplified fragment length polymorphism) techniques. Phenotypic variation included seed morphological characteristics, seed oil content and fatty acid composition and early growth traits. Jaccard’s similarity and cluster analysis by UPGM (Unweighted Paired Group Method) with arithmetic mean and PCA (Principle Component Analysis) indicated higher variability in Central American accessions compared to Asian, African and South American accessions. Polymorphism Information Content (PIC) values ranged from 0 to 0.65. In the set of Central American accessions. PIC values were higher than in other regions. Accessions from the Central American population contain alleles that were not found in the accessions from other populations. Analysis of Molecular Variance (AMOVA; P jatropha oil significantly differed (P < 0.05) between regions. Conclusions The pool of Central American accessions showed very large genetic variation as assessed by DNA-marker variation compared to accessions from other regions. Central American accessions also showed the highest phenotypic variation and should be considered as the most important source for plant breeding. Some variation in early growth traits was found within a group of accessions from Asia and Africa, while these accessions did not differ in a single DNA-marker, possibly indicating epigenetic variation. PMID:24666927

  13. Development of Renewable Energies in the liberation of the energy market in Central America

    International Nuclear Information System (INIS)

    Rebollo, Jose; Puente, Margarita; Cabezas, Jose

    2000-01-01

    This paper presents the diagnostic of the current situation on renewable energy in Central America, including socio-economical situation, with economical index, supply and demand of energy and planning of wind resources. The experience of Europe in the promotion for the market of renewable energy, discussing the policies and cooperation between private sector and the government is included. A list of potential projects of renewable energy in each country of Central America based on biomass, hydro power, wind and other energy sources for power generation is presented

  14. Cyanobacterial diversity in alkaline marshes of northern Belize (Central America)

    Czech Academy of Sciences Publication Activity Database

    Komárek, Jiří; Ventura, S.; Turicchia, S.; Komárková, Jaroslava; Mascalchi, C.; Soldati, E.

    2005-01-01

    Roč. 158, č. 117 (2005), s. 265-278 ISSN 0342-1120. [Symposium of the International Association for Cyanophyte Research /16./. Luxembourg, 30.08.2004-03.09.2004] R&D Projects: GA AV ČR(CZ) IAA6005309; GA AV ČR KSK6005114; GA MŠk(CZ) ME 653 Institutional research plan: CEZ:AV0Z6005908 Keywords : Cyanobacteria * alkaline marshes * Central Amerika Subject RIV: EF - Botanics

  15. Work and health in Latin America: results from the working conditions surveys of Colombia, Argentina, Chile, Central America and Uruguay.

    Science.gov (United States)

    Merino-Salazar, Pamela; Artazcoz, Lucía; Cornelio, Cecilia; Iñiguez, María José Itatí; Rojas, Marianela; Martínez-Iñigo, David; Vives, Alejandra; Funcasta, Lorena; Benavides, Fernando G

    2017-06-01

    To describe working and employment conditions, and health status between non-agricultural employees with a written contract from Colombia, Argentina, Chile, Central America and Uruguay. We compared data from the first working condition surveys (WCS) of Colombia, Argentina, Chile, Central America and Uruguay. For comparative purposes, we selected a subsample of 15 241 non-agricultural employees aged 18-64 years and working with a written contract. We calculated prevalences and 95% CIs for the selected variables on working and employment conditions, and health status, separated by sex. Across all countries, at least 40% of women and 58% of men worked >40 hours a week. The most prevalent exposures were repetitive movements, followed by noise and manual handling, especially among men. Psychosocial exposures were very common among both sexes. Workers in Chile (33.4% of women and 16.6% of men) and Central America (24.3% of women and 19.1% of men) were more likely to report poor self-perceived health and were least likely to do so in Colombia (5.5% of women and 4.2% of men). The percentage of workers reporting occupational injuries was work and health in different Latin American countries, based on the national WCSs available. This allows for a better understanding of occupational health and could serve as a baseline for future research and surveillance of work and health in the Region. However, greater efforts are needed to improve WCSs comparability. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. Central America Field Epidemiology Training Program (CA FETP): a pathway to sustainable public health capacity development

    OpenAIRE

    L?pez, Augusto; C?ceres, Victor M

    2008-01-01

    Abstract The Central America Field Epidemiology Training Program (CA FETP) is a public health capacity-building training programme aimed at developing high-caliber field epidemiologists at various levels of the public health system. It began in 2000 as part of the effort to rebuild public health infrastructure in six Central American and Caribbean countries following the devastation of Hurricanes Mitch and Georges in late 1998. Since then, the CA FETP has evolved from one regional training pr...

  17. Comparisons of LSMS-ISA data collection and dissemination efforts in Central America

    OpenAIRE

    Zúniga-González, Carlos Alberto

    2010-01-01

    This article aims the comparison of LSMS survey in Central American countries to increase current knowledge of survey methodologies and ensure the most efficient dissemination and utilization of the results. It will improve the availability, quality and relevance of agricultural data for policy and research in Central America. The criterion for this comparison consists of household survey data production, methodological validation/research, capacity building and dissemination. The...

  18. Scholastic achievement of adolescent refugees from Cambodia and Central America.

    Science.gov (United States)

    Rousseau, C; Drapeau, A

    2000-01-01

    This study investigated the relationship of emotional disturbance and pre- and postmigration environment to the scholastic achievement of adolescent refugees of very different cultural backgrounds. One hundred fifty-two Central American and Cambodian students in six Canadian high schools, as well as their parents, were interviewed to assess the students' emotional problems (using the Youth Self-Report and Child Behavior Checklist) and to determine the pre- and postmigration family environment. The findings indicated that the relationship between the emotional problems and scholastic achievement of teenaged refugees was tenuous. It was concluded that a connection between young refugees' symptomatology and their functional capacity should not be assumed. Nonetheless, certain pre- and postmigration variables, particularly trauma experienced in the homeland, seem to be associated with the academic achievement of some refugees.

  19. CO2 emissions, energy usage, and output in Central America

    International Nuclear Information System (INIS)

    Apergis, Nicholas; Payne, James E.

    2009-01-01

    This study extends the recent work of Ang (2007) [Ang, J.B., 2007. CO 2 emissions, energy consumption, and output in France. Energy Policy 35, 4772-4778] in examining the causal relationship between carbon dioxide emissions, energy consumption, and output within a panel vector error correction model for six Central American countries over the period 1971-2004. In long-run equilibrium energy consumption has a positive and statistically significant impact on emissions while real output exhibits the inverted U-shape pattern associated with the Environmental Kuznets Curve (EKC) hypothesis. The short-run dynamics indicate unidirectional causality from energy consumption and real output, respectively, to emissions along with bidirectional causality between energy consumption and real output. In the long-run there appears to be bidirectional causality between energy consumption and emissions.

  20. Phenology and recruitment of Caryocar costaricense (Caryocaceae, an endemic tree species of Southern Central America

    Directory of Open Access Journals (Sweden)

    Silvia Solís

    2009-09-01

    Full Text Available Basic aspects of the reproductive biology are largely unknown for most tropical tree species, although they are important elements to understand the impacts of anthropogenic activities as logging and forest fragmentation on these populations. In this study, data are presented on leaf and reproductive phenology, fruit production and seedling demography of a population of an endemic tree species of Southern Central America, Caryocar costaricense. This species has been affected by selective logging and forest fragmentation of its habitat. Phenology was studied by observation of 15-22 tree crowns during two reproductive periods (2003 and 2005. Circular plots were established around 11 adult trees to count the number of fallen fruits and seedlings during three years (2003, 2004, 2005. Although reproductive phenology is restricted to the short dry season in this species, seed germination occurred year-round. Fruit and seedling production shows a strong inter-individual variation within the study populations, with two large trees producing nearly 50%-70% of the fruits and seedlings during two years. Most of the seeds that fall beneath the tree crown are covered by litterfall or removed by fauna. We found evidence that many of these seeds become part of a seed bank in the forest floor. Because of the observed reproductive dominance of few large trees in these populations, we propose that selective logging on reproductive trees can severely impact the recruitment of this species. Rev. Biol. Trop. 57 (3: 771-780. Epub 2009 September 30.Los aspectos básicos de la biología reproductiva de árboles tropicales son en su mayoría desconocidos, aunque son conocimientos esenciales para entender el impacto de actividades antropogénicas como la tala selectiva y la fragmentación de bosques. En este estudio se presentan datos sobre la fenología foliar y reproductiva, la producción de frutos, y la demografía de plántulas de una población de Caryocar

  1. Central America Regional Climate Change Program: Tools for Your Use

    Science.gov (United States)

    Irwin, Dan; Irving, Bill; Yeager, Carey

    2006-01-01

    USAID/E-CAM and EGAT's Global Climate Change Team, in partnership with EPA, NASA, Oak Ridge National Lab, and the Central American Commission for Environment and Development (CCAD), have had a significant impact on the region's ability to monitor, mitigate, and adapt to environmental threats. Environmental decision-making tools and data are posted on a website (SERVIR: http://servir.nsstc.nasa.pov/home.html)that provides satellite and geographic data and maps to anybody with an Internet connection. The SERVIR program has been identified as the model for the Global Earth Observation System of Systems (GEOSS) - a major international effort to develop a 21st century system for environmental management and disaster response. In coordination with the USAID/EPA program, NASA has developed a GIs tool that enables countries to examine their forest cover and document changes on an annual basis. This information is used in calculating carbon emissions as part of greenhouse gas inventories, but also serves a valuable monitoring function. In addition, USAID/E-CAM and EGAT's Global Climate Change Team in collaboration with EPA are helping countries meet their obligations as signatories to the United Nations Framework Convention on Climate Change (UNFCCC). EPA is assisting Central American governments to improve the quality of their greenhouse gas emission inventories reported to the UNFCCC through the development of tools and improvements in data quality. New EPA tools developed include software to automatically calculate greenhouse gas emissions for the agricultural and forestry sector inventories, determine key sources of greenhouse gas emissions, and document institutional arrangements. Several of these tools are state of the art and are comparable to tools currently used in the U.S.

  2. Capacity-Building Programs Under the Dominican Republic-Central America-United States Free Trade Agreement (CAFTA-DR)

    Science.gov (United States)

    The United States signed the Dominican Republic-Central America-United States Free Trade Agreement (CAFTA-DR) in August 2004 with five Central American countries (Costa Rica, El Salvador, Guatemala, Honduras, and Nicaragua) and the Dominican Republic.

  3. Adapting Community-Based Water Supply in Central America to a ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    In Central America, nearly 24,000 community-based organizations supply drinking water to rural and peri-urban residents. By delivering potable water, these organizations improve the health and welfare of millions, and play a key role in local economic development. Climate change in the region is resulting in higher ...

  4. Description of three new species of Protodrilus (Annelida, Protodrilidae) from Central America

    DEFF Research Database (Denmark)

    Martinez Garcia, Alejandro; Di Domenico, Maikon; Jörger, Katharina

    2013-01-01

    on the prostomium. This first exploration of Protodrilus along the Caribbean coast of Central America revealed five new species (three described here), but not P. corderoi, a species described from Brazil and recorded at Dominica. The findings indicate a putative high diversity of Protodrilus species in the Western...

  5. Post Doctorate Award on Central America and the Caribbean at St ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    This grant will allow St Antony's College at the University of Oxford to establish a 2-year post doctoral position on Central America and the Caribbean under the leadership of Canadian historian, Margaret MacMillan. The position will be awarded to a scholar from the region, in keeping with IDRC's philosophy that developing ...

  6. [The first experience wih ICSI and MESA in Panama, Central America and the Caribbean].

    Science.gov (United States)

    Alleyne, C; Sánchez, F

    1998-01-01

    The intracytoplasmic sperm injection (ICSI) has represented an important advance in human reproduction technology, improving the results in those couples with a very low probability of achieving pregnancy. Our aim is present the results of our first experience with ICSI and MESA in Panama, Central America and the Caribe.

  7. Devil Pact Narratives in Rural Central America : Class, Gender and 'Resistance'

    NARCIS (Netherlands)

    Jansen, K.; Roquas, E.

    2002-01-01

    The Faustian bargain, or 'pact with the devil', made by a person who exchanges human souls in order to obtain unattainable riches and power, is a widespread peasant narrative in Central and South America. The narrative expresses various overlapping meanings, of which a sudden increase in wealth and

  8. Unaccompanied Refugee Minors from Central America: Understanding Their Journey and Implications for Counselors

    Science.gov (United States)

    Tello, Angelica M.; Castellon, Nancy E.; Aguilar, Alejandra; Sawyer, Cheryl B.

    2017-01-01

    The United States has recently seen a significant increase in the number of unaccompanied minors from the Northern Triangle of Central America (i.e., El Salvador, Honduras, and Guatemala). These children and youth are refugees fleeing extreme poverty and gang violence. This study examined the narratives of 16 refugees from the Northern Triangle…

  9. Armed conflict and poverty in Central America: the convergence of epidemiology and human rights advocacy.

    Science.gov (United States)

    Brentlinger, Paula E; Hernán, Miguel A

    2007-11-01

    Several armed conflicts took place in Central America during the last 3 decades of the 20th century. In this commentary, we discuss (1) studies describing the interrelationships among health, violence, and poverty during and after these conflicts and (2) some important lessons learned from these studies. We hope that those lessons help epidemiologists and others who must confront, and describe, similar situations elsewhere.

  10. Book review: Vetter, H. 2005. Terralog. Turtles of the World. Vol. 3. Central and South America

    Directory of Open Access Journals (Sweden)

    2006-12-01

    Full Text Available Book review: Vetter, H. 2005. Terralog. Turtles of the World. Vol. 3. Central and South America/Schildkröten der Welt Band 3. Mittel- und Südamerika: 1-128, color pictures 606 + 9. Edition Chimaira, Frankfurt, Germany.ISBN 3-930612-82-8; 29.7 x 20.8 cm

  11. Inferences on the hydrothermal system beneath the resurgent dome in Long Valley Caldera, east-central California, USA, from recent pumping tests and geochemical sampling

    Science.gov (United States)

    Farrar, Christopher D.; Sorey, Michael L.; Roeloffs, Evelyn; Galloway, Devin L.; Howle, James F.; Jacobson, Ronald

    2003-10-01

    Quaternary volcanic unrest has provided heat for episodic hydrothermal circulation in the Long Valley caldera, including the present-day hydrothermal system, which has been active over the past 40 kyr. The most recent period of crustal unrest in this region of east-central California began around 1980 and has included periods of intense seismicity and ground deformation. Uplift totaling more than 0.7 m has been centered on the caldera's resurgent dome, and is best modeled by a near-vertical ellipsoidal source centered at depths of 6-7 km. Modeling of both deformation and microgravity data now suggests that (1) there are two inflation sources beneath the caldera, a shallower source 7-10 km beneath the resurgent dome and a deeper source ˜15 km beneath the caldera's south moat and (2) the shallower source may contain components of magmatic brine and gas. The Long Valley Exploration Well (LVEW), completed in 1998 on the resurgent dome, penetrates to a depth of 3 km directly above this shallower source, but bottoms in a zone of 100°C fluid with zero vertical thermal gradient. Although these results preclude extrapolations of temperatures at depths below 3 km, other information obtained from flow tests and fluid sampling at this well indicates the presence of magmatic volatiles and fault-related permeability within the metamorphic basement rocks underlying the volcanic fill. In this paper, we present recently acquired data from LVEW and compare them with information from other drill holes and thermal springs in Long Valley to delineate the likely flow paths and fluid system properties under the resurgent dome. Additional information from mineralogical assemblages in core obtained from fracture zones in LVEW documents a previous period of more vigorous and energetic fluid circulation beneath the resurgent dome. Although this system apparently died off as a result of mineral deposition and cooling (and/or deepening) of magmatic heat sources, flow testing and tidal

  12. Corporate good citizenship pays off in Central America.

    Science.gov (United States)

    1974-07-22

    Fear of expropriation and increasing public scrutiny of the activities of multinational companies are forcing these companies to develop social programs in the countries where they operate. Frequently these programs are viewed as products of colonialism or as veiled attempts to dominate the nationals employed by these companies. The United Brands Company, which is involved in large scale banana production in several Central American countries, has adopted a program which seeks to reduce the paternalism which was associated with the operations of the United Fruit Company, the predecessor of the United Brands Company. A series of new programs emphasizing community self help projects were developed by a company-hired sociologist and initiated 4 years ago. In Panama, the projects were started by holding town meetings in which the citizens decided what projects to pursue. With company help the community has begun to build recreational and educational facilities and are also building new docks. The company is contributing $10 million annually to promote these projects. Other programs involve selling homes to workers for half the cost of constructing these homes and increasing efforts to put host country citizens into management positions. Home ownership is expected to stabilize the work force and increased opportunities for advancement are expected to increase productivity. Future plans include the construction of technical schools which will provide a pool of skilled technicians needed by the banana company.

  13. Hydrogeochemical investigation of six geothermal sites in Honduras, Central America

    Energy Technology Data Exchange (ETDEWEB)

    Goff, F.E.; Truesdell, A.H.; Grigsby, C.O.; Janik, C.J.; Shevenell, L.A.; Paredes, J.R.; Gutierrez, J.W.; Trujillo, Jr.; Counce, D.A.

    1987-06-01

    We conducted detailed hydrogeochemical investigations at six geothermal sites in western Honduras: Azacualpa, El Olivar, Pavana, Platanares, Sambo Creek, and San Ignacio. None of the sites is associated with Quaternary silicic volcanism, although El Olivar lies adjacent to a small Quaternary basalt field and Pavana is part of a belt of hot spring activity parallel to and 35 km east of the Central American volcanic arc. None of the sites contains acid-sulfate waters indicative of vapor-dominated conditions. Thermal fluids are characterized by pH between 7 and 10, Cl<125 mg/l, HCO/sub 3/>Cl, SO/sub 4/greater than or equal toCl, Bless than or equal to17 mg/l, Liless than or equal to4 mg/l, and Asless than or equal to1.25 mg/l. Stable isotope analyses of the water show that recharge to the geothermal systems generally occurs from areas of higher elevation adjacent to the sites. Tritium contents of apparently undiluted thermal fluids range from 0 to 0.4 T.U., indicating residence times of fluids in the systems of more than 500 y. Various geochemical indicators show that mixing of hot and cold end-member fluids occurs in the system at Platanares and, to a lesser degree, in the systems at San Ignacio and Azacualpa. No mixing is apparent in the fluids discharging at Pavana, Sambo Creek, or El Olivar. Boiling is the dominant process responsible for subtle geochemical variations at Azacualpa and, possibly, San Ignacio. Our best estimates of subsurface reservoir temperatures are 225/sup 0/C at Platanares, 190/sup 0/C at San Ignacio, 185/sup 0/C at Azacualpa, 155/sup 0/C at Sambo Creek, 150/sup 0/C at Pavana, and 120/sup 0/C at El Olivar. The estimated power output of the three hottest sites is 45 thermal megawatts at Platanares, 14 thermal megawatts at San Ignacio, and 13 thermal megawatts at Azacualpa.

  14. Mapping agricultural landscapes and characterizing adaptive capacity in Central America

    Science.gov (United States)

    Holland, M. B.; Imbach, P. A.; Bouroncle, C.; Donatti, C.; Leguia, E.; Martinez, M.; Medellin, C.; Saborio-Rodriguez, M.; Shamer, S.; Zamora, J.

    2013-12-01

    One of the key challenges in developing adaptation strategies for smallholder farmers in developing countries is that of a data-poor environment, where spatially-explicit information about where the most vulnerable smallholder communities are located is lacking. Developing countries tend to lack consistent and reliable maps on agricultural land use, and have limited information available on smallholder adaptive capacity. We developed a novel participatory and expert mapping process to overcome these barriers and develop detailed national-scale maps that allow for a characterization of unique agricultural landscapes based on profiles of adaptive capacity for smallholder agriculture in each area. This research focuses specifically on the Central American nations of Costa Rica, Guatemala, and Honduras, where our focus is on coffee and basic grains as the two main cropping systems. Here we present the methodology and results of a series of in-depth interviews and participatory mapping sessions with experts working within the broader agricultural sector in each country. We held individual interviews and mapping sessions with approximately thirty experts from each country, and used a detailed survey instrument for each mapping session to both spatially identify distinct agricultural landscapes, and to further characterize each area based on specific farm practices and social context. The survey also included a series of questions to help us assess the relative adaptive capacity of smallholder agriculture within each landscape. After all expert mapping sessions were completed in each country we convened an expert group to assist in both validating and refining the set of landscapes already defined. We developed a characterization of adaptive capacity by aggregating indicators into main assets-based criteria (e.g. land tenure, access to credit, access to technical assistance, sustainable farm practices) derived from further expert weighting of indicators through an online

  15. A five-century sedimentary geochronology of biomass burning in Nicaragua and Central America

    International Nuclear Information System (INIS)

    Suman, D.O.

    1991-01-01

    In spite of the extensive use of fire as an agricultural agent in Central America today, little is known of its history of biomass burning or agriculture. As an indicator of the burning practices on the adjacent land, a sedimentary record of carbonized particles sheds light on the trends in frequency and areal extent of biomass burning. This research focuses on a sediment core recovered from an anoxic site in the Pacific Ocean adjacent to the Central American Isthmus and reports a five-century record of charcoal deposition. The research illustrates that biomass burning has been an important ecological factor in the Pacific watershed of Central America at least during the past five centuries. Fluxes of charcoal have generally decreased toward the present suggesting a reduction in the charcoal source function. Perhaps, five centuries ago, the frequency of biomass burning was greater than it is today, larger areas were burned, or biomass per unit area of burned grassland was greater. The major type of biomass burned throughout this five-century period has been grass, as opposed to woods, indicating that any major deforestation of the Pacific watershed of Central America occurred prior to the Conquest

  16. The implications of trade liberalization for diet and health: a case study from Central America

    Directory of Open Access Journals (Sweden)

    Hawkes Corinna

    2009-07-01

    Full Text Available Abstract Background Central America has undergone extensive trade liberalization over the past two decades, and has recently signed a Free Trade Agreement with the United States. The region is also experiencing a dual burden of malnutrition with the growth of dietary patterns associated with the global 'nutrition transition'. This study describes the relationship between trade liberalization policies and food imports and availability, and draws implications for diet and health, using Central America as a case study region. Methods Changes in tariff and non-tariff barriers for each country were documented, and compared with time-series graphs of import, production and availability data to show the outcome of changes in trade policy in relation to food imports and food availability. Results Changes in trade policy in Central America have directly affected food imports and availability via three avenues. First, the lowering of trade barriers has promoted availability by facilitating higher imports of a wide range of foods. Second, trade liberalization has affected food availability through promoting domestic meat production. Third, reductions in barriers to investment appear to be critical in expansion of processed food markets. This suggests that changes in trade policies have facilitated rising availability and consumption of meat, dairy products, processed foods and temperate (imported fruits in Central America. Conclusion This study indicates that the policies of trade liberalization in Central American countries over the past two decades, particularly in relation to the United States, have implications for health in the region. Specifically, they have been a factor in facilitating the "nutrition transition", which is associated with rising rates of obesity and chronic diseases such as cardiovascular disease and cancer. Given the significant cost of chronic disease for the health care system, individuals and the wider community, it is critical

  17. The implications of trade liberalization for diet and health: a case study from Central America

    Science.gov (United States)

    Thow, Anne Marie; Hawkes, Corinna

    2009-01-01

    Background Central America has undergone extensive trade liberalization over the past two decades, and has recently signed a Free Trade Agreement with the United States. The region is also experiencing a dual burden of malnutrition with the growth of dietary patterns associated with the global 'nutrition transition'. This study describes the relationship between trade liberalization policies and food imports and availability, and draws implications for diet and health, using Central America as a case study region. Methods Changes in tariff and non-tariff barriers for each country were documented, and compared with time-series graphs of import, production and availability data to show the outcome of changes in trade policy in relation to food imports and food availability. Results Changes in trade policy in Central America have directly affected food imports and availability via three avenues. First, the lowering of trade barriers has promoted availability by facilitating higher imports of a wide range of foods. Second, trade liberalization has affected food availability through promoting domestic meat production. Third, reductions in barriers to investment appear to be critical in expansion of processed food markets. This suggests that changes in trade policies have facilitated rising availability and consumption of meat, dairy products, processed foods and temperate (imported fruits) in Central America. Conclusion This study indicates that the policies of trade liberalization in Central American countries over the past two decades, particularly in relation to the United States, have implications for health in the region. Specifically, they have been a factor in facilitating the "nutrition transition", which is associated with rising rates of obesity and chronic diseases such as cardiovascular disease and cancer. Given the significant cost of chronic disease for the health care system, individuals and the wider community, it is critical that preventive health

  18. A rapid diversification of rainforest trees (Guatteria; Annonaceae) following dispersal from Central into South America.

    Science.gov (United States)

    Erkens, Roy H J; Chatrou, Lars W; Maas, Jan W; van der Niet, Timotheüs; Savolainen, Vincent

    2007-07-01

    Several recent studies have suggested that a substantial portion of today's plant diversity in the Neotropics has resulted from the dispersal of taxa into that region rather than vicariance, but more data are needed to substantiate this claim. Guatteria (Annonaceae) is, with 265 species, the third largest genus of Neotropical trees after Inga (Fabaceae) and Ocotea (Lauraceae), and its widespread distribution and frequent occurrence makes the genus an excellent model taxon to study diversification patterns. This study reconstructed the phylogeny of Guatteria and inferred three major biogeographical events in the history of the genus: (1) a trans-oceanic Miocene migration from Central into South America before the closing of the Isthmus of Panama; (2) a major diversification of the lineage within South America; and (3) several migrations of South American lineages back into Central America via the closed Panamanian land bridge. Therefore, Guatteria is not an Amazonian centred-genus sensu Gentry but a major Miocene diversification that followed its dispersal into South America. This study provides further evidence that migration into the Neotropics was an important factor in the historical assembly of its biodiversity. Furthermore, it is shown that phylogenetic patterns are comparable to those found in Ocotea and Inga and that a closer comparison of these genera is desirable.

  19. Neoliberal Forms of Capital and The Rise of Social Movement Partyism in Central America

    Directory of Open Access Journals (Sweden)

    Paul Almeida

    2015-08-01

    Full Text Available Historical shifts in global economic formations shape the strategies of resistance movements in the global South. Neoliberal forms of economic development over the past thirty years in Central America have weakened traditional actors sponsoring popular mobilization such as labor unions and rural cooperatives. At the same time, the free market reforms produced new threats to economic livelihood and well-being throughout the region. The neoliberal measures that have generated the greatest levels of mass discontent include rising prices, privatization, labor flexibility laws, mining projects, and free trade. This article analyzes the role of emerging anti-neoliberal political parties in alliance with popular movements in Central America. Countries with already existing strong anti-systemic parties in the initial phases of the global turn to neoliberalism in the late twentieth century resulted in more efficacious manifestations of social movement partyism in the twenty-first century resisting free market globalization.

  20. New species of Brachiacantha Dejean, 1837 (Coleoptera: Coccinellidae) from Mexico and Central America.

    Science.gov (United States)

    Nestor-Arriola, Jorge Ismael; Toledo-Hernández, Víctor Hugo

    2017-12-15

    Five new species of the genus Brachiacantha Dejean (Coccinellidae) from Mexico and Central America are described and illustrated. The species B. angulata sp. nov., B. truncata sp. nov., B. brevicuspidata sp. nov. and B. robustihamata sp. nov. are consistent with the dentipes group. The species B. brevihamata sp. nov. is consistent with the fifth group of Leng (1911); the species shares some characteristics with South American species.

  1. Migrant Young Children from Central America: the Faces of the Poor Public Investment

    OpenAIRE

    Gatica López, Gustavo Adolfo

    2015-01-01

    This article discusses why the situation of migration for Central American children and young people to the United States of America and the declared humanitarian crisis should begin with a review of the structural conditions affecting the population in the region. The poor public social investment in children and adolescents as well as the various forms of violence perpetrated against them in the region are two very indispensable elements for this analysis. By not considering these elements ...

  2. Coupled Global-Regional Climate Model Simulations of Future Changes in Hydrology over Central America

    Science.gov (United States)

    Oglesby, R. J.; Erickson, D. J.; Hernandez, J. L.; Irwin, D.

    2005-12-01

    Central America covers a relatively small area, but is topographically very complex, has long coast-lines, large inland bodies of water, and very diverse land cover which is both natural and human-induced. As a result, Central America is plagued by hydrologic extremes, especially major flooding and drought events, in a region where many people still barely manage to eke out a living through subsistence. Therefore, considerable concern exists about whether these extreme events will change, either in magnitude or in number, as climate changes in the future. To address this concern, we have used global climate model simulations of future climate change to drive a regional climate model centered on Central America. We use the IPCC `business as usual' scenario 21st century run made with the NCAR CCSM3 global model to drive the regional model MM5 at 12 km resolution. We chose the `business as usual' scenario to focus on the largest possible changes that are likely to occur. Because we are most interested in near-term changes, our simulations are for the years 2010, 2015, and 2025. A long `present-day run (for 2005) allows us to distinguish between climate variability and any signal due to climate change. Furthermore, a multi-year run with MM5 forced by NCEP reanalyses allows an assessment of how well the coupled global-regional model performs over Central America. Our analyses suggest that the coupled model does a credible job simulating the current climate and hydrologic regime, though lack of sufficient observations strongly complicates this comparison. The suite of model runs for the future years is currently nearing completion, and key results will be presented at the meeting.

  3. Interannual variability of the midsummer drought in Central America and the connection with sea surface temperatures

    OpenAIRE

    Maldonado, Tito; Rutgersson, Anna; Alfaro, Eric; Amador, Jorge; Claremar, Björn

    2016-01-01

    The midsummer drought (MSD) in Central America is characterised in order to create annual indexes representing the timing of its phases (start, minimum and end), and other features relevant for MSD forecasting such as the intensity and the magnitude. The MSD intensity is defined as the minimum rainfall detected during the MSD, meanwhile the magnitude is the total precipitation divided by the total days between the start and end of the MSD. It is shown that the MSD extends al...

  4. The Soviet-Cuban Connection in Central America and the Caribbean

    Science.gov (United States)

    1985-04-01

    is on such ideals as " socialistA Strong Supporter of solidarity," Castro is known to charge many of these Communist Expansion countries for Cuban...Nacion Internacional (San Jose, Costa !Pop Rica), November 20-24, 1983. 19. This speech was carried in Spanish in its entirety in La Prensa (San Pedro...Salvador, on July 8, 1984. on Central America, prepared for the Presi- dent. Henry A. Kissinger, Chairman. Washing- 45. La Nacion Internacional (San Jose

  5. [Musculoskeletal pain in Central American workers: results of the First Survey on Working Conditions and Health in Central America].

    Science.gov (United States)

    Rojas, Marianela; Gimeno, David; Vargas-Prada, Sergio; Benavides, Fernando G

    2015-08-01

    Examine the prevalence of musculoskeletal pain (MSP) in the six Spanish-speaking countries of Central America using a single standardized instrument, the First Survey on Working Conditions and Health in Central America in workers from all manual and non-manual labor sectors, using social security coverage as an indicator of formal versus informal employment. The workers (n = 12 024) were surveyed in their homes. The age-adjusted prevalence of MSP during the previous month was calculated for pain in the back (upper, or cervical; middle, or thoracic; and lower, or lumbar) and arm joints (shoulder, elbow, and wrist). Prevalence was estimated by sex, occupation (manual or non-manual), economic sector (agriculture, industry, or services), and social security coverage. Poisson regression models were used to calculate the prevalence rates and 95% confidence intervals, with stratification by country and anatomical site. By sites, the age-adjusted prevalence of cervical-dorsal MSP was the highest, especially in El Salvador (47.8%) and Nicaragua (45.9%), and lumbar MSP was less prevalent, especially in Panama (12.8%) and Guatemala (14.8%). After additional adjustments, the prevalence of MSP was higher in women and manual workers for all the sites and in all the countries. There were no differences in MSP in terms of social security coverage or sector of economic activity. The high prevalence of MSP in Central America, regardless of sector of activity or social security coverage, indicates that the prevention of MSP should be a priority in occupational health programs in low- and middle-income countries, especially for women and manual workers.

  6. Active mountain building and the distribution of core Maxillariinae species in tropical Mexico and Central America

    Science.gov (United States)

    Kirby, Stephen H.

    2011-01-01

    The observation that southeastern Central America is a hotspot for orchid diversity has long been known and confirmed by recent systematic studies and checklists. An analysis of the geographic and elevation distribution demonstrates that the most widespread species of “core” Maxillariinae are all adapted to life near sea level, whereas the most narrowly endemic species are largely distributed in wet highland environments. Drier, hotter lowland gaps exist between these cordilleras and evidently restrict the dispersal of the species adapted to wetter, cooler conditions. Among the recent generic realignments of “core” Maxillariinae based on molecular phylogenetics, the Camaridium clade is easily the most prominent genus in Central America and is largely restricted to the highlands of Costa Rica and Panama, indicating that this region is the ancestral home of this genus and that its dispersal limits are drier, lowland cordilleran gaps. The mountains of Costa Rica and Panama are among the geologically youngest topographic features in the Neotropics, reflecting the complex and dynamic interactions of numerous tectonic plates. From consideration of the available geological evidence, I conclude that the rapid growth of the mountain ranges in Costa Rica and Panama during the late Cenozoic times created, in turn, very rapid ranges in ecological life zones and geographic isolation in that part of the isthmus. Thus, I suggest that these recent geologic events were the primary drivers for accelerated orchid evolution in southeastern Central America.

  7. Land-Atmosphere Coupling in the Central America and Caribbean Region

    Science.gov (United States)

    Arritt, R. W.

    2016-12-01

    We use results from a regional climate model to investigate the influence of land-atmosphere coupling on climate of the Central America and Caribbean. Previous studies using global climate models have found evidence of strong land-atmosphere coupling in parts of this region. Although the region's complex coastlines and topography have the potential to modify land-atmosphere coupling through their influence on surface fluxes and precipitation, these terrain features are represented coarsely if at all in global models. Here we better resolve the complex terrain of Central America by using 25 and 50 km grid spacing in a regional climate model (RegCM4). Simulations over the Central America and Caribbean domain of the Coordinated Regional climate Downscaling Experiment (CORDEX) with ERA-Interim reanalysis boundary conditions for 1989-2009 are used to calculate multiple diagnostic measures of land-atmosphere coupling. Land-atmosphere coupling "hot spots" are found to differ in both location and magnitude from those obtained using global models. Location and intensity of these "hot spots" vary depending on model physics and spatial resolution.

  8. Seismogenic Structure Beneath Décollement Inferred from 2009/11/5 ML 6.2 Mingjian Earthquake in Central Taiwan

    Directory of Open Access Journals (Sweden)

    Che-Min Lin

    2014-01-01

    Full Text Available One decade after the 1999 Chi-Chi earthquake, central Taiwan experienced more strong ground shaking [Central Weather Bureau (CWB, intensity VII] induced by a ML 6.2 earthquake on 5th November 2009. This earthquake occurred in the Mingjian Township of Nantou County, only 12 km southwest of the Chi-Chi earthquake epicenter. The broadband microearthquake monitoring network operated by the National Center for Research on Earthquake Engineering (NCREE observed numerous aftershocks in the five days following the mainshock. The relocated aftershocks and the mainshock focal mechanism indicated a NE-SW striking fault dipping 60¢X toward the northwest. This fault plane is inside the pre-Miocene basement and the rupture extends from the lower crust to 10 km depth just beneath the basal décollement of the thin-skinned model that is generally used to explain the regional tectonics in Taiwan. The fault plane is vertically symmetrical with the Chelungpu fault by the basal décollement. The NW-SE compressive stress of plate collision in Taiwan, as well as the deep tectonic background, resulted in the seismogenic structure of the Mingjian earthquake at this location.

  9. Prevalence of metabolic syndrome in Central America: a cross-sectional population-based study

    Directory of Open Access Journals (Sweden)

    Roy A. Wong-McClure

    2015-09-01

    Full Text Available OBJECTIVE: To report the prevalence of metabolic syndrome (MetS as found by the Central American Diabetes Initiative (CAMDI study for five major Central American populations: Belize (national; Costa Rica (San José; Guatemala (Guatemala City; Honduras (Tegucigalpa; and Nicaragua (Managua. METHODS: Study data on 6 185 adults aged 20 years or older with anthropometric and laboratory determination of MetS from population-based surveys were analyzed. Overall, the survey response rate was 82.0%. MetS prevalence was determined according to criteria from the Adult Treatment Panel III of the National Cholesterol Education Program. The study's protocol was reviewed and approved by the bioethical committee of each country studied. RESULTS: The overall standardized prevalence of MetS in the Central American region was 30.3% (95% confidence interval (CI: 27.1-33.4. There was wide variability by gender and work conditions, with higher prevalence among females and unpaid workers. The standardized percentage of the population free of any component of MetS was lowest in Costa Rica (9.0%; CI: 6.5-11.4 and highest in Honduras (21.1%; CI: 16.4-25.9. CONCLUSIONS: Overall prevalence of MetS in Central America is high. Strengthening surveillance of chronic diseases and establishing effective programs for preventing cardiovascular diseases might reduce the risk of MetS in Central America.

  10. Localized double-array stacking analysis of PcP: D″ and ULVZ structure beneath the Cocos plate, Mexico, central Pacific, and north Pacific

    Science.gov (United States)

    Hutko, Alexander R.; Lay, Thorne; Revenaugh, Justin

    2009-01-01

    A large, high quality P-wave data set comprising short-period and broadband signals sampling four separate regions in the lowermost mantle beneath the Cocos plate, Mexico, the central Pacific, and the north Pacific is analyzed using regional one-dimensional double-array stacking and modelling with reflectivity synthetics. A data-screening criterion retains only events with stable PcP energy in the final data stacks used for modelling and interpretation. This significantly improves the signal stacks relative to including unscreened observations, allows confident alignment on the PcP arrival and allows tight bounds to be placed on P-wave velocity structure above the core–mantle boundary (CMB). The PcP reflections under the Cocos plate are well modelled without any ultra-low velocity zone from 5 to 20°N. At latitudes from 15 to 20°N, we find evidence for two P-wave velocity discontinuities in the D″ region. The first is ∼182 km above the CMB with a δln Vp of +1.5%, near the same depth as a weaker discontinuity (<+0.5%) observed from 5 to 15°N in prior work. The other reflector is ∼454 km above the CMB, with a δln Vp of +0.4%; this appears to be a shallower continuation of the joint P- and S-wave discontinuity previously detected south of 15° N, which is presumed to be the perovskite to post-perovskite phase transition. The data stacks for paths bottoming below Mexico have PcP images that are well matched with the simple IASP91 structure, contradicting previous inferences of ULVZ presence in this region. These particular data are not very sensitive to any D″ discontinuities, and simply bound them to be <∼2%, if present. Data sampling the lowermost mantle beneath the central Pacific confirm the presence of a ∼15-km thick ultra-low velocity zone (ULVZ) just above the CMB, with δln Vp and δln Vs of around −3 to −4% and −4 to −8%, respectively. The ULVZ models predict previous S-wave data stacks well. The data for this region

  11. [Trends in the urbanization process in Central America in the 1980's].

    Science.gov (United States)

    Lungo Ucles, M

    1990-01-01

    In the 1980s, urbanization in Central America was increasing compared to the three previous decades. By 1990, the urban population reached 42% in Guatemala, 44% in El Salvador, 43% in Honduras, 59% in Nicaragua, 53% in Costa Rica, and 54% in Panama. The urban population increased mostly in the largest cities, in contrast to Latin America, where secondary cities grew fastest. This trend was particularly true in Managua and San Salvador because of the military conflicts. The only exception was Honduras, where the second city underwent stronger growth. The urban population comprised 51.7% women and 48.3% men in Central America. The segregation and polarization of social classes was also increasing because of increased poverty and unemployment during the 1980s. This was partly caused by the increasing privatization of public services, decentralization, and the reinforcement of local governments, which all ensued from the structural readjustment programs of the International Monetary Fund. This neoliberal model of economic development in the short run resulted in increased poverty and unemployment for the urban populations. In 1982, the informal sector represented 29% of the total employment in Central America, and its share reached 40% in Managua and San Salvador. Urban unemployment increased from 2.2% in 1980 to 12% in 1988 in Guatemala; from 8.8% to 13.1% in Honduras; and from 10.4% to 20.8% in Panama. In the political arena, the process of democratization was underway, with civil presidents taking power and promoting privatization and deregulation of the economy. There was a close relationship between the urban social structure, the economy, and politics in the region. In Costa Rica, during the Arias administration between 1986 and 1990, a program was implemented creating 80,000 new homes, and in El Salvador there was an increasing demand to find a negotiated solution to the military conflict. These new political and economic perspectives could lead to genuine

  12. Different educational glances in two pedagogical congresses : Cuba (1884 and Central America (1893

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    Amalia Nivón Bolán

    2014-12-01

    Full Text Available The 19th Century pedagogical congresses carried out in Cuba and Central America were led by teachers and officials involved in the educational policy of primary education, and aware of the need to adjust the education’s foundation in order to react to the moment’s reality. This piece analyses the special conditions in Cuba and Central America that cause the reform of the primary education grounds that prevailed in schools during the Colony in the 18th and 19th Centuries. It also describes the protagonists in the educational practice elite that influenced the restruturing of the school system, knowledge and learning techniques, as well as the teachers’ educational or occupational profile. In addition, it outlines the economic circumstances and the political view of the groups of intellectuals trained in a context that inherited the legacy of the colonial conditions of racism and defense of agricultural and industrial work, and defined by abolitionist and pro-independence struggles.  The study was conducted from the UNESCO Memory of the First Central Pedagogical Congress and current research that relate to the Cuban Congress 1884, to identify educational activities and careers of influential intellectuals in shaping Cuban and Central American educational systems at sundown nineteenth century.

  13. Pre-Hispanic agricultural decline prior to the Spanish Conquest in southern Central America

    Science.gov (United States)

    Taylor, Zachary P.; Horn, Sally P.; Finkelstein, David B.

    2013-08-01

    Archeological and paleoenvironmental records from southern Central America attribute population collapse to the Spanish Conquest about 500 years ago. Paleoclimate records from the circum-Caribbean have shown evidence of severe, regional droughts that contributed to the collapse of the Mayan Civilization, but there are few records of these droughts in southern Central America and no records of their effects on prehistoric populations in the region. Here we present a high-resolution lake sediment record of prehistoric agricultural activities using bulk sediment stable carbon isotopes from Laguna Zoncho, Costa Rica. We find isotopic evidence that agriculture was nearly absent from the watershed approximately 220 years prior to the Spanish arrival in Costa Rica and identify two distinct periods of agricultural decline, 1150-970 and 860-640 cal yr BP, which correspond to severe droughts in central Mexico. We attribute decreases in agriculture to a weakened Central American monsoon, which would have shortened the growing season at Laguna Zoncho, reduced crop yields, and negatively affected prehistoric populations.

  14. Scorpionism in Central America, with special reference to the case of Panama

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    A Borges

    2012-01-01

    Full Text Available Scorpionism in the Americas occurs mainly in Mexico, northern South America and southeast Brazil. This article reviews the local scorpion fauna, available health statistics, and the literature to assess scorpionism in Central America. Notwithstanding its high toxicity in Mexico, most scorpion sting cases in Guatemala, Belize, El Salvador, Nicaragua, and Costa Rica are produced by species in the genus Centruroides that are only mildly toxic to humans despite the existence of ion channel-active toxins in their venoms. Regional morbidity is low with the exception of Panama, where an incidence of 52 cases per 100,000 inhabitants was recorded for 2007, with 28 deaths from 1998 to 2006. Taxa belonging to the genus Tityus (also present in the Atlantic coast of Costa Rica are responsible for fatalities in Panama, with Tityus pachyurus being the most important species medically. Most Tityus species inhabiting Panama are also found in northern South America from which they probably migrated upon closure of the Panamanian isthmus in the Miocene era. Incorporation of Panama as part of the northern South American endemic area of scorpionism is thereby suggested based on the incidence of these accidents and the geographical distribution of Panamanian Tityus species.

  15. Mantle transition zone beneath central-eastern Greenland: Possible evidence for a deep tectosphere from receiver functions

    Science.gov (United States)

    Kraft, Helene Anja; Vinnik, Lev; Thybo, Hans

    2018-03-01

    We investigate the mantle of central-eastern Greenland by using recordings with data from 24 local broad-band seismograph stations. We apply P wave receiver function technique and evaluate the difference in the arrival times of seismic phases that are formed by P to SV mode conversion at the 410-km and 660-km seismic discontinuities. These boundaries mark the top and bottom of the mantle transition zone (MTZ). The difference in the arrival time of the phases from the 410-km and 660-km discontinuities is sensitive to the thickness of the MTZ and relatively insensitive to volumetric velocity anomalies above the 410-km discontinuity. Near the east coast of Greenland in the region of the Skaergaard basalt intrusions we find two regions where the differential time is reduced by more than 2 s. The 410-km discontinuity in these regions is depressed by more than 20 km. The depression may be explained by a temperature elevation of 150 °C. We hypothesize that the basaltic intrusions and the temperature anomalies at a depth of 400 km are, at least partly, effects of the passage of Greenland over the Iceland hotspot at about 55 Ma. This explanation is consistent with the concept of tectosphere and implies that the upper mantle to a depth of 400 km translates coherently with the Greenland plate.

  16. Development and Analysis of a Hurricane Hazard Model for Disaster Risk Assessment in Central America

    Science.gov (United States)

    Pita, G. L.; Gunasekera, R.; Ishizawa, O. A.

    2014-12-01

    Hurricane and tropical storm activity in Central America has consistently caused over the past decades thousands of casualties, significant population displacement, and substantial property and infrastructure losses. As a component to estimate future potential losses, we present a new regional probabilistic hurricane hazard model for Central America. Currently, there are very few openly available hurricane hazard models for Central America. This resultant hazard model would be used in conjunction with exposure and vulnerability components as part of a World Bank project to create country disaster risk profiles that will assist to improve risk estimation and provide decision makers with better tools to quantify disaster risk. This paper describes the hazard model methodology which involves the development of a wind field model that simulates the gust speeds at terrain height at a fine resolution. The HURDAT dataset has been used in this study to create synthetic events that assess average hurricane landfall angles and their variability at each location. The hazard model also then estimates the average track angle at multiple geographical locations in order to provide a realistic range of possible hurricane paths that will be used for risk analyses in all the Central-American countries. This probabilistic hurricane hazard model is then also useful for relating synthetic wind estimates to loss and damage data to develop and calibrate existing empirical building vulnerability curves. To assess the accuracy and applicability, modeled results are evaluated against historical events, their tracks and wind fields. Deeper analyses of results are also presented with a special reference to Guatemala. The findings, interpretations, and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the views of the International Bank for Reconstruction and Development/World Bank and its affiliated organizations, or those of the

  17. Magmatic Activity Beneath the Quiescent Three Sisters Volcanic Center, Central Oregon Cascade Range, USA, Inferred from Satellite InSAR

    Science.gov (United States)

    Wicks, C. W.; Dzurisin, D.; Ingebritsen, S.; Thatcher, W.; Lu, Z.; Iverson, J.

    2001-12-01

    Images from satellite interferometric synthetic aperture radar (InSAR) reveal uplift of a broad ~10 km by 20 km area in the Three Sisters volcanic center of the central Oregon Cascade Range, ~130 km south of Mt. St. Helens. The uplift is centered ~5 km west of South Sister volcano, the youngest stratovolcano in the volcanic center. The center has been volcanically inactive since the last eruption ~1500 years ago. Multiple European Space Agency ERS-1 and 2 satellite images from 1992 through 2000, used in this study, were selected based on orbital separation and time of year. Summer and early autumn scenes were necessary to avoid decorrelation from snow cover. Interferograms generated from these images indicate that most if not all of ~100 mm of observed uplift occurred between September 1998 and October 2000. We interpret the uplift as inflation caused by an apparently ongoing episode of magma intrusion at a depth of ~6.5 km. Geochemical (water chemistry) anomalies, first noted ~1990, coincide with the area of uplift and suggest the existence of a magma reservoir prior to the uplift. High chloride and sulfate concentrations, and a positive correlation between chloride concentration and spring temperature were found within the uplift area, with larger SO4/Cl ratios in springs at higher elevations. These findings are indicative of a high-temperature hydrothermal system driven by magma intrusions. The current inflation episode observed with InSAR may lead to an eruption, but the more persistent geochemical evidence suggests that the episode is likely the latest in a series of hitherto undetected magma intrusions. We do not yet know if the inflation has abated, is continuing, or has accelerated since October 2000--we only know that the highest rate of uplift occurred in the last year for which ERS-2 data was available (1999- 2000). In May of 2001, a continuous GPS receiver and seismometer were installed by the USGS within the Three Sisters Wilderness to monitor the

  18. Young mafic back arc volcanic rocks as indicators of continental lithospheric delamination beneath the Argentine Puna plateau, central Andes

    Science.gov (United States)

    Kay, Suzanne Mahlburg; Coira, Beatriz; Viramonte, Jose

    1994-12-01

    The spatial distribution of some major and trace element and isotopic characteristics of backarc Plio-Quaternary basaltic to high-Mg andesitic (51% to 58% SiO2) lavas in the southern Puna (25 S to 27 S) of the Central Andean Volcanic Zone (CVZ) reflect varying continental lithospheric thickness and the thermal state of the underlying mantle wedge and subducting plate. These lavas erupted from small cones and fissures associated with faults related to a change in the regional stress system in the southern Puna at approximately = 2 to 3 Ma. Three geochemical groups are recognized: (1) a relatively high volume intraplate group (high K; La/Ta ratio less than 25) that occurs over a thin continental lithosphere above a gap in the modern seismic zone and represents the highest percentage of mantle partial melt, (2) an intermediate volume, high-K calc-alkaline group (La/Ta ratio greater than 25) that occurs over intermediate thickness lithosphere on the margins of the seismic gap and behind the main CVZ and represents an intermediate percentage of mantle partial melt, and (3) a small-volume shoshonitic group (very high K) that occurs over relatively thick continental lithosphere in the northeast Puna and Altiplano and represents a very small percentage of mantle partial melt. Mantle-generated characteristics of these lavas are partially overprinted by mixing with melts of the overlying thickened crust as shown by the presence of quartz and feldspar xenocrysts, negative Eu anomalies (Eu/E(sup *) less than 0.90; most less than 0.80), and radiogenic Sr (greater than 0.7055) and Pb and nonradiogenic Nd (epsilon(sub Nd) less than -0.4) isotopic ratios. Mixing calculations show that the lavas generally contain more than 20% to 25% crustal melt. The eruption of the intraplate group mafic lavas, the change in regional stress orientation, and the high elevation of the southern Puna are suggested to be the result of the late Pliocene mechanical delamination of a block (or blocks) of

  19. Central America in Transition: From Maize to Wheat Challenges and Opportunities

    Directory of Open Access Journals (Sweden)

    Amado Salvador Peña

    2015-08-01

    Full Text Available The Central American countries: Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, and Panama are in transition from a dietary culture based mainly on maize to a wheat-containing diet. Several other changes are occurring, such as a decrease of parasitic and infectious diseases. The environmental changes permit a prediction of an increase of celiac disease and other autoimmune diseases such as type I diabetes and thyroid disease in these genetically heterogeneous countries. At present, celiac disease and gluten-related disorders are considered to be of no relevance at the level of public health in these nations. This review documents the presence of celiac disease in Central America. It draws attention to some of the challenges in planning systematic studies in the region since up until recently celiac disease was unknown. The aim of this review is to disseminate knowledge obtained with preliminary data, to stimulate clinical and basic scientists to study these diseases in Central America and to alert authorities responsible for the planning of education and health, to find possibilities to avoid a rise in these disorders before the epidemics start, as has occurred in the Mediterranean countries.

  20. Seismic hazard maps of Mexico, the Caribbean, and Central and South America

    Science.gov (United States)

    Tanner, J.G.; Shedlock, K.M.

    2004-01-01

    The growth of megacities in seismically active regions around the world often includes the construction of seismically unsafe buildings and infrastructures due to an insufficient knowledge of existing seismic hazard and/or economic constraints. Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends on reliable estimates of seismic hazard. We have produced a suite of seismic hazard estimates for Mexico, the Caribbean, and Central and South America. One of the preliminary maps in this suite served as the basis for the Caribbean and Central and South America portion of the Global Seismic Hazard Map (GSHM) published in 1999, which depicted peak ground acceleration (pga) with a 10% chance of exceedance in 50 years for rock sites. Herein we present maps depicting pga and 0.2 and 1.0 s spectral accelerations (SA) with 50%, 10%, and 2% chances of exceedance in 50 years for rock sites. The seismicity catalog used in the generation of these maps adds 3 more years of data to those used to calculate the GSH Map. Different attenuation functions (consistent with those used to calculate the U.S. and Canadian maps) were used as well. These nine maps are designed to assist in global risk mitigation by providing a general seismic hazard framework and serving as a resource for any national or regional agency to help focus further detailed studies required for regional/local needs. The largest seismic hazard values in Mexico, the Caribbean, and Central and South America generally occur in areas that have been, or are likely to be, the sites of the largest plate boundary earthquakes. High hazard values occur in areas where shallow-to-intermediate seismicity occurs frequently. ?? 2004 Elsevier B.V. All rights reserved.

  1. A spatio-temporal analysis of forest loss related to cocaine trafficking in Central America

    Science.gov (United States)

    Sesnie, Steven E.; Tellman, Beth; Wrathall, David; McSweeney, Kendra; Nielsen, Erik; Benessaiah, Karina; Wang, Ophelia; Rey, Luis

    2017-05-01

    A growing body of evidence suggests that criminal activities associated with drug trafficking networks are a progressively important driver of forest loss in Central America. However, the scale at which drug trafficking represents a driver of forest loss is not presently known. We estimated the degree to which narcotics trafficking may contribute to forest loss using an unsupervised spatial clustering of 15 spatial and temporal forest loss patch metrics developed from global forest change data. We distinguished anomalous forest loss from background loss patches for each country exhibiting potential ‘narco-capitalized’ signatures which showed a statistically significant dissimilarity from other patches in terms of size, timing, and rate of forest loss. We also compared annual anomalous forest loss with the number of cocaine shipments and volume of cocaine seized, lost, or delivered at country- and department-level. For Honduras, results from linear mixed effects models showed a highly significant relationship between anomalous forest loss and the timing of increased drug trafficking (F = 9.90, p = 0.009) that also differed significantly from temporal patterns of background forest loss (t-ratio = 2.98, p = 0.004). Other locations of high forest loss in Central America showed mixed results. The timing of increased trafficking was not significantly related to anomalous forest loss in Guatemala and Nicaragua, but significantly differed in patch size compared to background losses. We estimated that cocaine trafficking could account for between 15% and 30% of annual national forest loss in these three countries over the past decade, and 30% to 60% of loss occurred within nationally and internationally designated protected areas. Cocaine trafficking is likely to have severe and lasting consequences in terms of maintaining moist tropical forest cover in Central America. Addressing forest loss in these and other tropical locations will require a stronger

  2. COELIAC DISEASE IN CENTRAL AND SOUTH AMERICA: time for a concerted approach to its epidemiology

    Directory of Open Access Journals (Sweden)

    Affifa FARRUKH

    2015-06-01

    Full Text Available Central and South America offer an opportunity to resolve some of the current controversies that surround the epidemiology of celiac disease. Through a concerted action which brings together clinicians, researchers and patients there is an opportunity to establish robust data sets which will allow detailed analysis of environmental and genetic factors. In this review available data from the continent together with data from Spain and Italy are drawn together to give a current picture in the hope that it will stimulate further research.

  3. Potential impact of climate change on coffee rust over Mexico and Central America

    Science.gov (United States)

    Calderon-Ezquerro, Maria del Carmen; Martinez-Lopez, Benjamin; Cabos Narvaez, William David; Sein, Dmitry

    2017-04-01

    In this work, some meteorological variables from a regional climate model are used to characterize the dispersion of coffee rust (a fungal disease) from Central America to Mexico, during the 20 Century. The climate model consists of the regional atmosphere model REMO coupled to the MPIOM global ocean model with increased resolution in the Atlantic Ocean. Lateral atmospheric and upper oceanic boundary conditions outside the coupled domain were prescribed using both ERA-40 and ERA-Interim reanalysis data. In addition to the historical simulation, a projection of the evolution of the coffee rust for the 21 Century was obtained from a REMO run using MPIESM data for the lateral forcing.

  4. Interannual variability of the midsummer drought in Central America and the connection with sea surface temperatures

    Directory of Open Access Journals (Sweden)

    T. Maldonado

    2016-04-01

    Full Text Available The midsummer drought (MSD in Central America is characterised in order to create annual indexes representing the timing of its phases (start, minimum and end, and other features relevant for MSD forecasting such as the intensity and the magnitude. The MSD intensity is defined as the minimum rainfall detected during the MSD, meanwhile the magnitude is the total precipitation divided by the total days between the start and end of the MSD. It is shown that the MSD extends along the Pacific coast, however, a similar MSD structure was detected also in two stations in the Caribbean side of Central America, located in Nicaragua. The MSD intensity and magnitude show a negative relationship with Niño 3.4 and a positive relationship with the Caribbean low-level jet (CLLJ index, however for the Caribbean stations the results were not statistically significant, which is indicating that other processes might be modulating the precipitation during the MSD over the Caribbean coast. On the other hand, the temporal variables (start, minimum and end show low and no significant correlations with the same indexes.The results from canonical correlation analysis (CCA show good performance to study the MSD intensity and magnitude, however, for the temporal indexes the performance is not satisfactory due to the low skill to predict the MSD phases. Moreover, we find that CCA shows potential predictability of the MSD intensity and magnitude using sea surface temperatures (SST with leading times of up to 3 months. Using CCA as diagnostic tool it is found that during June, an SST dipole pattern upon the neighbouring waters to Central America is the main variability mode controlling the inter-annual variability of the MSD features. However, there is also evidence that the regional waters are playing an important role in the annual modulation of the MSD features. The waters in the PDO vicinity might be also controlling the rainfall during the MSD, however, exerting an

  5. The social perspective of desertification: Analysis of the public administration perception in Central America

    International Nuclear Information System (INIS)

    Garay Romero, Ingrid Carolina; Cabero Dieguez, Valentin

    2013-01-01

    Desertification is a complex problem and not only represents terrestrial ecosystems degradation. Today, it is well known that this process is linked to environmental deterioration as well as to economic and social factors, producing relevant impact in food security, poverty, migration and imbalance in many countries. Desertification perception analysis is essential in the design of the policies to fight this problem. Perception analysis in Central America is a very controversial issue and should be part of administration instruments and application strategies such as international agreements that will be included in public policies of the different States.

  6. Moisture transport across Central America as a positive feedback on abrupt climatic changes.

    Science.gov (United States)

    Leduc, Guillaume; Vidal, Laurence; Tachikawa, Kazuyo; Rostek, Frauke; Sonzogni, Corinne; Beaufort, Luc; Bard, Edouard

    2007-02-22

    Moisture transport from the Atlantic to the Pacific ocean across Central America leads to relatively high salinities in the North Atlantic Ocean and contributes to the formation of North Atlantic Deep Water. This deep water formation varied strongly between Dansgaard/Oeschger interstadials and Heinrich events-millennial-scale abrupt warm and cold events, respectively, during the last glacial period. Increases in the moisture transport across Central America have been proposed to coincide with northerly shifts of the Intertropical Convergence Zone and with Dansgaard/Oeschger interstadials, with opposite changes for Heinrich events. Here we reconstruct sea surface salinities in the eastern equatorial Pacific Ocean over the past 90,000 years by comparing palaeotemperature estimates from alkenones and Mg/Ca ratios with foraminiferal oxygen isotope ratios that vary with both temperature and salinity. We detect millennial-scale fluctuations of sea surface salinities in the eastern equatorial Pacific Ocean of up to two to four practical salinity units. High salinities are associated with the southward migration of the tropical Atlantic Intertropical Convergence Zone, coinciding with Heinrich events and with Greenland stadials. The amplitudes of these salinity variations are significantly larger on the Pacific side of the Panama isthmus, as inferred from a comparison of our data with a palaeoclimate record from the Caribbean basin. We conclude that millennial-scale fluctuations of moisture transport constitute an important feedback mechanism for abrupt climate changes, modulating the North Atlantic freshwater budget and hence North Atlantic Deep Water formation.

  7. Controls on the fore-arc CO2 flux along the Central America margin

    Science.gov (United States)

    Hilton, D. R.; Barry, P. H.; Ramirez, C. J.; Kulongoski, J. T.; Patel, B. S.; Virrueta, C.; Blackmon, K.

    2015-12-01

    The subduction of carbon to the deep mantle via subduction zones is interrupted by outputs via the fore-arc, volcanic front, and back-arc regions. Whereas output fluxes for arc and back-arc locales are well constrained for the Central America Volcanic Arc (CAVA) [1-2], the fore-arc flux via cold seeps and ground waters is poorly known. We present new He and CO2 data (isotopes and relative abundances) for the volcanic front and inner fore-arc of western Panama to complement on-going studies of fore-arc C-fluxes in Costa Rica [3-4] and to determine tectonic controls on the fore-arc C-outgassing fluxes. Helium isotope (3He/4He) values at Baru, La Yeguada, and El Valle volcanoes are high (5-8RA), consistent with results for other Central America volcanoes. However, CO2/3He values are variable (from > 1012 to Baru has an arc-like δ13C of - 4‰, whereas the other volcanoes have δ13C Baru volcano. The transition from orthogonal subduction of the Cocos Plate to oblique subduction of the Nazca Plate, relative to the common over-riding Caribbean Plate, is the major impediment to slab degassing towards the southern terminus of the CAVA. [1] Shaw et al., 2003, EPSL; [2] De Leeuw et al., 2007, EPSL; [3] Furi et al, 2010, G-cubed; [4] Hilton et al. 2014, Fall AGU.

  8. SALTRA: a regional program for workers' health and sustainable development in Central America.

    Science.gov (United States)

    Wesseling, Catharina; Aragón, Aurora; Elgstrand, Kaj; Flores, Reinaldo; Hogstedt, Christer; Partanen, Timo

    2011-01-01

    In 2003, the university-based Program on Work and Health in Central America, SALTRA, was launched to build national and regional capacities in occupational safety and health with the goal of preventing and reducing poverty in Central America. SALTRA has implemented 20 projects including action projects in priority sectors (e.g., construction, sugarcane, hospitals, migrant coffee workers); strengthening of surveillance (occupational health profiles, carcinogenic exposures, fatal injuries and pesticides); a participatory model for training and risk monitoring by workers; building occupational health capacity for professionals, employers, and workers, with collaborating networks between the countries; strengthening of universities in work, environment, and health; studies of serious occupational and environmental situations; communication channels; and continued efforts to raise political awareness. SALTRA has placed issues of workers' health on political, business, and academic agendas throughout the region and has laid the foundations for achieving substantial future improvements in health conditions of all workers in the region. External evaluators envisioned SALTRA as an innovative development model.

  9. [Cost-benefit analysis: HIV/AIDS prevention in migrants in Central America].

    Science.gov (United States)

    Alarid-Escudero, Fernando; Sosa-Rubí, Sandra G; Fernández, Bertha; Galárraga, Omar

    2013-07-01

    To quantify the costs and benefits of three HIV prevention interventions in migrants in Central America: voluntary counseling and testing, treatment of sexually transmitted infections, and condom distribution. The methods were: a) identification and quantification of costs; b) quantification of benefits, defined as the potential savings in antiretroviral treatment of HIV cases prevented; and c) estimation of the cost-benefit ratio. The model estimated that 9, 21 and 8 cases of HIV were prevented by voluntary counseling and testing, treatment for sexually transmitted infections and condom distribution per 10 000 migrants, respectively. In Panama, condom distribution and treatment for sexually transmitted infections had a return of US$131/USD and US$69.8/USD. Returns in El Salvador were US$2.0/USD and US$42.3/USD in voluntary counseling and testing and condom distribution, respectively. The potential savings on prevention have a large variation between countries. Nevertheless, the cost-benefit estimates suggest that the HIV prevention programs in Central America can potentially result in monetary savings in the long run.

  10. Global change and the distributional dynamics of migratory bird populations wintering in Central America.

    Science.gov (United States)

    La Sorte, Frank A; Fink, Daniel; Blancher, Peter J; Rodewald, Amanda D; Ruiz-Gutierrez, Viviana; Rosenberg, Kenneth V; Hochachka, Wesley M; Verburg, Peter H; Kelling, Steve

    2017-12-01

    Understanding the susceptibility of highly mobile taxa such as migratory birds to global change requires information on geographic patterns of occurrence across the annual cycle. Neotropical migrants that breed in North America and winter in Central America occur in high concentrations on their non-breeding grounds where they spend the majority of the year and where habitat loss has been associated with population declines. Here, we use eBird data to model weekly patterns of abundance and occurrence for 21 forest passerine species that winter in Central America. We estimate species' distributional dynamics across the annual cycle, which we use to determine how species are currently associated with public protected areas and projected changes in climate and land-use. The effects of global change on the non-breeding grounds is characterized by decreasing precipitation, especially during the summer, and the conversion of forest to cropland, grassland, or peri-urban. The effects of global change on the breeding grounds are characterized by increasing winter precipitation, higher temperatures, and the conversion of forest to peri-urban. During spring and autumn migration, species are projected to encounter higher temperatures, forests that have been converted to peri-urban, and increased precipitation during spring migration. Based on current distributional dynamics, susceptibility to global change is characterized by the loss of forested habitats on the non-breeding grounds, warming temperatures during migration and on the breeding grounds, and declining summer rainfall on the non-breeding grounds. Public protected areas with low and medium protection status are more prevalent on the non-breeding grounds, suggesting that management opportunities currently exist to mitigate near-term non-breeding habitat losses. These efforts would affect more individuals of more species during a longer period of the annual cycle, which may create additional opportunities for species to

  11. Coral zonation and diagenesis of an emergent Pleistocene patch reef, Belize, Central America

    Energy Technology Data Exchange (ETDEWEB)

    Lighty, R.G.; Russell, K.L.

    1985-01-01

    Transect mapping and petrologic studies reveal a new depositional model and limited diagenesis of a well-exposed Pleistocene reef outcrop at Ambergris Cay, northern Belize. This emergent shelf-edge reef forms a rocky wave-washed headland at the northern terminus of the present-day 250 km long flourishing Belize Barrier Reef. Previously, the Belize reef outcrop was thought to extend southward in the subsurface beneath the modern barrier reef as a Pleistocene equivalent. The authors study indicate that this outcrop is a large, coral patch reef and not part of a barrier reef trend. Sixteen transects 12.5 m apart described in continuous cm increments from fore reef to back reef identified: extensive deposits of broken Acropora cervicornis; small thickets of A. palmata with small, oriented branches; and muddy skeletal sediments with few corals or reef rubble. Thin section and SEM studies show three phases of early submarine cementation: syntaxial and rosette aragonite; Mg-calcite rim cement and peloids; and colloidal Mg-calcite geopetal fill. Subaerial exposure in semi-arid northern Belize caused only minor skeletal dissolution, some precipitation of vadose whisker calcite, and no meteoric phreatic diagenesis. Facies geometry, coral assemblages, lack of rubble deposits, coralline algal encrustations and Millepora framework, and recognition of common but discrete submarine cements, all indicate that this Pleistocene reef was an isolated, coral-fringed sediment buildup similar to may large patch reefs existing today in moderate-energy shelf environments behind the modern barrier reef in central and southern Belize.

  12. A review of bioinformatics training applied to research in molecular medicine, agriculture and biodiversity in Costa Rica and Central America.

    Science.gov (United States)

    Orozco, Allan; Morera, Jessica; Jiménez, Sergio; Boza, Ricardo

    2013-09-01

    Today, Bioinformatics has become a scientific discipline with great relevance for the Molecular Biosciences and for the Omics sciences in general. Although developed countries have progressed with large strides in Bioinformatics education and research, in other regions, such as Central America, the advances have occurred in a gradual way and with little support from the Academia, either at the undergraduate or graduate level. To address this problem, the University of Costa Rica's Medical School, a regional leader in Bioinformatics in Central America, has been conducting a series of Bioinformatics workshops, seminars and courses, leading to the creation of the region's first Bioinformatics Master's Degree. The recent creation of the Central American Bioinformatics Network (BioCANET), associated to the deployment of a supporting computational infrastructure (HPC Cluster) devoted to provide computing support for Molecular Biology in the region, is providing a foundational stone for the development of Bioinformatics in the area. Central American bioinformaticians have participated in the creation of as well as co-founded the Iberoamerican Bioinformatics Society (SOIBIO). In this article, we review the most recent activities in education and research in Bioinformatics from several regional institutions. These activities have resulted in further advances for Molecular Medicine, Agriculture and Biodiversity research in Costa Rica and the rest of the Central American countries. Finally, we provide summary information on the first Central America Bioinformatics International Congress, as well as the creation of the first Bioinformatics company (Indromics Bioinformatics), spin-off the Academy in Central America and the Caribbean.

  13. Drought assessment for cropland of Central America using course-resolution remote sensing data

    Science.gov (United States)

    Chen, C. F.; Nguyen, S. T.; Chen, C. R.; Chiang, S. H.; Chang, L. Y.; Khin, L. V.

    2015-12-01

    Drought is one of the most frequent and costliest natural disasters, which imposes enormous effects to human societies and ecosystems. Agricultural drought is referred to an interval of time, such as weeks or months, when the soil moisture supply of a region consistently falls below the appropriate moisture supply leading to negative impacts on agricultural production. Millions of households in Central America were dependent upon major food crops, including maize, beans, and sorghum, for their daily subsistence. In recent years, impacts of climate change through global warming in forms of higher temperature and widespread rainfall deficits have however triggered severe drought during the primera cropping season (April-August) in the study region, causing profound impacts on agriculture, crop production losses, increased market food prices, as well as food security issues. This study focuses on investigating agricultural droughts for cropland of Central America using the Moderate Resolution Imaging Spectroradiometer (MODIS) data. We processed the data for a normal year 2013 and an abnormal year 2014 using a simple vegetation health index (VHI) that is developed based on the temperature condition index (TCI) and vegetation condition index (VCI). The VHI results were validated using the Advanced Microwave Scanning Radiometer 2 (AMSR2) precipitation data and temperature vegetation dryness index (TVDI) that is developed based on the empirical analysis of TCI and VCI data. The correlation coefficients (r) obtained by comparisons between the VHI data and the AMSR2 precipitation and TVDI data were higher than 0.62 and -0.61, respectively. The severe drought was intensive during the dry season (January-April) and likely backed to normal conditions in May with the onset of rainy season. The larger area of serve drought was observed for the 2014 primera season, especially during April-July. When investigating the cultivated areas affected by severe drought in the primera

  14. Central America Field Epidemiology Training Program (CA FETP): a pathway to sustainable public health capacity development.

    Science.gov (United States)

    López, Augusto; Cáceres, Victor M

    2008-12-16

    The Central America Field Epidemiology Training Program (CA FETP) is a public health capacity-building training programme aimed at developing high-caliber field epidemiologists at various levels of the public health system. It began in 2000 as part of the effort to rebuild public health infrastructure in six Central American and Caribbean countries following the devastation of Hurricanes Mitch and Georges in late 1998. Since then, the CA FETP has evolved from one regional training programme managed by CDC to several national FETPs with each country assuming ownership of its domestic programme. The curriculum is competency-based, and is divided into a three-tiered training pyramid that corresponds to the needs at the local, district and central levels of the health system. Trainees at each tier spend about 20% of their time in the classroom and 80% in the field implementing what they have learned while being mentored by graduates of the programme. FETP trainees have responded to multiple natural disasters and conducted hundreds of investigations including surveillance evaluations, outbreak responses and planned studies. Also graduates of the CA FETP are assuming influential positions in their respective ministries. As countries meet the challenge of institutionalizing their programmes, the CA FETP concept will increasingly be recognized as a model for sustainable public health capacity development.

  15. Central America Field Epidemiology Training Program (CA FETP: a pathway to sustainable public health capacity development

    Directory of Open Access Journals (Sweden)

    Cáceres Victor M

    2008-12-01

    Full Text Available Abstract The Central America Field Epidemiology Training Program (CA FETP is a public health capacity-building training programme aimed at developing high-caliber field epidemiologists at various levels of the public health system. It began in 2000 as part of the effort to rebuild public health infrastructure in six Central American and Caribbean countries following the devastation of Hurricanes Mitch and Georges in late 1998. Since then, the CA FETP has evolved from one regional training programme managed by CDC to several national FETPs with each country assuming ownership of its domestic programme. The curriculum is competency-based, and is divided into a three-tiered training pyramid that corresponds to the needs at the local, district and central levels of the health system. Trainees at each tier spend about 20% of their time in the classroom and 80% in the field implementing what they have learned while being mentored by graduates of the programme. FETP trainees have responded to multiple natural disasters and conducted hundreds of investigations including surveillance evaluations, outbreak responses and planned studies. Also graduates of the CA FETP are assuming influential positions in their respective ministries. As countries meet the challenge of institutionalizing their programmes, the CA FETP concept will increasingly be recognized as a model for sustainable public health capacity development.

  16. [Population mobility and HIV/AIDS in Central America and Mexico].

    Science.gov (United States)

    Leyva-Flores, René; Aracena-Genao, Belkis; Serván-Mori, Edson

    2014-09-01

    Estimate the magnitude of the association between population mobility, measured by net migration rate (NMR), and HIV prevalence in Central America and Mexico. Using time series models, based on public information from UNAIDS, UNDP, ECLAC, and the World Bank for the period 1990-2009, this association was studied in individuals aged 15-49 years, and adjusted for socioeconomic factors (education, unemployment, life expectancy, and income). NMR was negative in all countries except Costa Rica and Panama. Unadjusted results of the model show a positive association and that NMR can explain 6% of recorded HIV prevalence. When socioeconomic cofactors are included by country (education, health, and income), the magnitude increases to 9% (PCentral America and Mexico, although large gaps persist among countries. The modest association observed between population mobility and HIV prevalence is conditioned by the socioeconomic status of the countries studied. Information availability limited the study's ability to establish the existence of this association with greater certainty. Accordingly, based on available information, it is not possible to affirm that migration plays a key role in the spread of HIV.

  17. Consensus between genes and stones in the biogeographic and evolutionary history of Central America

    Science.gov (United States)

    Gutiérrez-García, Tania Anaid; Vázquez-Domínguez, Ella

    2013-05-01

    Results from genetic and geologic studies can be combined to elucidate some general patterns of the biogeographic and evolutionary history of Central America (CA) and of its biota. Based on an ample review of geologic, biogeographic and genetic studies, our aim was to examine how common genetic patterns can be linked with geologic processes. Considering information about geologic and tectonic evolution of CA, we subdivided the region into four tectonic blocks: Maya, Chortis, Chorotega and Chocó. Species exchange between North/South America and CA encompasses three events: a first migration during the Late Cretaceous-Early Paleocene, a second through a terrestrial corridor preceding the formation of the Isthmus of Panama (IP), and the third involving a major dispersion through the IP. Such events caused similar genetic differentiation patterns and left a signature on the diversification of extant taxa, which we propose as three evolutionary groups: 1) Mayan, characterized by marked genetic structure and divergence, multiple refugia and formation of cryptic species; 2) Mid-CA, defined by high differentiation at the population level and between highland and lowlands, associated with intense volcanic activity; 3) Panamian, distinguished by migration from north to south and vice versa via de IP, with markedly high species divergence and speciation.

  18. Screening of anti-bacterial activity of medicinal plants from Belize (Central America).

    Science.gov (United States)

    Camporese, A; Balick, M J; Arvigo, R; Esposito, R G; Morsellino, N; De Simone, F; Tubaro, A

    2003-07-01

    Twenty-one extracts from seven herbal drugs, Aristolochia trilobata (Aristolochiaceae) leaves and bark, Bursera simaruba (Burseraceae) bark, Guazuma ulmifolia (Sterculiaceae) bark, Hamelia patens (Rubiaceae) leaves and Syngonium podophyllum (Araceae) leaves and bark, used in traditional medicine of Belize (Central America) as deep and superficial wound healers, were evaluated for their anti-bacterial properties. Activity was tested against standard strains of Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923 and Enterococcus faecalis ATCC 29212. Almost all the extracts were able to inhibit the growth of one or more of the bacterial strains, except that of Enterococcus faecalis. For the first time an anti-microbial activity is reported for Aristolochia trilobata as well as for Syngonium podophyllum. The hexane extracts of Aristolochia trilobata leaves and bark were the most active extracts against Staphylococcus aureus (MIC=0.31 and 0.625mg/ml, respectively).

  19. Love in the Time of War. Affections and Disaffections in the Testimonial Literature of Central America

    Directory of Open Access Journals (Sweden)

    José Domingo Carrillo Padilla

    2013-07-01

    Full Text Available The article aims to know the relationships established between the militants of the armed movements. Also want to be aware of the relationship model that prevailed. To achieve the proposed objectives, leave aside the narratives that glorify the armed movements, prevents build heroes to taste, rather, is a narrative of the adventures and the loving sinventuras who sought by weapons, to relieve the power ruler in Central America in the second half of the 20th century. The relationships established between the militants of the armed movements, regulated by traditional institutions such as marriage and free joints. In this article, because the nature of the sources this was said, emphasis in heterosexual affective relationships. There is know in the same way, homosexual relations between the guerrillas. Taboo because it means to infringe against the virility of men in arms and the model of femininity established by society. Son amores that even they dare not speak its name.

  20. Characterization of Trypanosoma rangeli Strains Isolated in Central and South America: an Overview

    Directory of Open Access Journals (Sweden)

    Grisard Edmundo C

    1999-01-01

    Full Text Available Trypanosoma rangeli is a hemoflagelate parasite that infects domestic and sylvatic animals, as well as man, in Central and South America. T. rangeli has an overlapping distribution with T. cruzi, the etiological agent of Chagas disease, sharing several animal reservoirs and triatomine vectors. We have isolated T. rangeli strains in the State of Santa Catarina, in southern Brazil, which dramatically increased the distribution area of this parasite. This brief review summarizes several studies comparing T. rangeli strains isolated in Santa Catarina with others isolated in Colombia, Honduras and Venezuela. The different methods used include indirect immunofluorescence and western blot assays, lectin agglutination, isoenzyme electrophoresis and random amplified polymorphic DNA analysis, triatomine susceptibility, in vitro cell infection assays, and mini-exon gene analysis.

  1. [International migration in Central America in the 1990s: causes, implications, and consequences].

    Science.gov (United States)

    Alvarado Umanzor, R A

    1993-04-01

    "After [reviewing] the demographic and historical backgrounds as well as the situation in each individual country in the area, the author concludes that migrations in Central America have been originated and influenced mainly by social and economic causes, as well as by social-political conflicts in the area, the latter affecting especially El Salvador, Nicaragua, Guatemala and Panama. Although bringing some relief to the families through remittances of money earned abroad, the general effects are negative for countries of origin, due to the loss of labor [and] ruptures in family relations. On the other hand, they significantly influence labor markets in the countries of destination, such as Costa Rica, Honduras, Mexico and the United States. The countries in the area must now prepare themselves to receive many of those migrants back home." (SUMMARY IN ENG) excerpt

  2. The Spanish decentralised international cooperation in Central America in the area of municipalism and decentralisation

    Directory of Open Access Journals (Sweden)

    Mariana Haedo

    2005-05-01

    Full Text Available In an attempt to link the international dimension with the local one, this article lays out an approach to the situation of Spanish decentralised international cooperation in the area of municipalism and decentralisation in the countries of Central America. In the firstplace, it offers a characterisation of the current state of Spanish decentralised cooperation in order to thus frame the cooperation actions carried out by the Barcelona Provincial Council; the UIM (Unión Iberoamericana de Municipios together with CEMCI (Centro de Estudios Municipales y de Cooperación Internacional; and the Confederación de Fondos de Cooperación y Solidaridad. Finally, it describes bankruptcies and it recovers some of the achievements ofthis kind of cooperation specifically in reference to the field of municipalism.

  3. Open Skies aerial photography of selected areas in Central America affected by Hurricane Mitch

    Science.gov (United States)

    Molnia, Bruce; Hallam, Cheryl A.

    1999-01-01

    Between October 27 and November 1, 1998, Central America was devastated by Hurricane Mitch. Following a humanitarian relief effort, one of the first informational needs was complete aerial photographic coverage of the storm ravaged areas so that the governments of the affected countries, the U.S. agencies planning to provide assistance, and the international relief community could come to the aid of the residents of the devastated area. Between December 4 and 19, 1998 an Open Skies aircraft conducted five successful missions and obtained more than 5,000 high-resolution aerial photographs and more than 15,000 video images. The aerial data are being used by the Reconstruction Task Force and many others who are working to begin rebuilding and to help reduce the risk of future destruction.

  4. Geothermal power plants of Mexico and Central America: a technical survey of existing and planned installations

    Energy Technology Data Exchange (ETDEWEB)

    DiPippo. R.

    1978-07-01

    In this report, the fifth in a series describing the geothermal power plants of the world, the countries of Mexico and of Central America are studied. The geothermal plants are located in areas of recent and active volcanism; the resources are of the liquid-dominated type. Details are given about the plants located at Cerro Prieto in Mexico and at Ahuachapan in El Salvador. In both cases, attention is paid to the geologic nature of the fields, the well programs, geofluid characteristics, energy conversion systems, materials of construction, effluent handling systems, economic factors and plant operating experience. Exploration and development activities are described for other promising geothermal areas in Mexico and El Salvador, along with those in the countries of Costa Rica, Nicaragua, Guatemala, Honduras, and Panama.

  5. A new species of arboreal pitviper from the Atlantic versant of northern Central America.

    Science.gov (United States)

    Campbell, J A; Smith, E N

    2000-12-01

    A new species of green, prehensile-tailed pitviper of the genus Bothriechis is described from the Atlantic slopes of eastern Guatemala and western Honduras. This species appears to be most closely related to B. bicolor of the Pacific versant of Chiapas (Mexico) and Guatemala. Several other species of Bothriechis occur on the Atlantic versant of northern Central America, including two montane species, B. aurifer and B. marchi but, with one possible exception, these are not known to be sympatric with the new species and occur in different mountain ranges. The widespread B. schlegelii occurs up to at least 900 m on the Sierra de Caral, where the lowest elevation recorded for the new species is 885 m.

  6. First record of the invasive Asian fish tapeworm Bothriocephalus acheilognathi in Honduras, Central America.

    Science.gov (United States)

    Salgado-Maldonado, Guillermo; Matamoros, Wilfredo A; Kreiser, Brian R; Caspeta-Mandujano, Juan Manuel; Mendoza-Franco, Edgar F

    2015-01-01

    This paper provides the first report of the invasive Asian fish tapeworm, Bothriocephalus acheilognathi Yamaguti, 1934, in Honduras. The cestode was found in Profundulus portillorum (Cyprinodontiformes: Profundulidae), which represents a new host record, and which is a member of a genus faced with a variety of conservation challenges, now potentially complicated by the presence of this pathogenic cestode. Nearly complete sequence data from the ITS-1 5.8S and ITS-2 regions corroborate the determination based on morphological characteristics. Several species of carp were introduced to Honduras for aquaculture purposes in the early 1980s and the presence of the Asian fish tapeworm in Honduras may be related to these introductions. In addition, this report documents the currently known geographical distribution of this parasite in Central America, first recorded from Panamá and now from Honduras. © G. Salgado-Maldonado et al., published by EDP Sciences, 2015.

  7. Cancer survival in Africa, Asia, and Central America: a population-based study.

    Science.gov (United States)

    Sankaranarayanan, Rengaswamy; Swaminathan, Rajaraman; Brenner, Hermann; Chen, Kexin; Chia, Kee Seng; Chen, Jian Guo; Law, Stephen C K; Ahn, Yoon-Ok; Xiang, Yong Bing; Yeole, Balakrishna B; Shin, Hai Rim; Shanta, Viswanathan; Woo, Ze Hong; Martin, Nimit; Sumitsawan, Yupa; Sriplung, Hutcha; Barboza, Adolfo Ortiz; Eser, Sultan; Nene, Bhagwan M; Suwanrungruang, Krittika; Jayalekshmi, Padmavathiamma; Dikshit, Rajesh; Wabinga, Henry; Esteban, Divina B; Laudico, Adriano; Bhurgri, Yasmin; Bah, Ebrima; Al-Hamdan, Nasser

    2010-02-01

    Population-based cancer survival data, a key indicator for monitoring progress against cancer, are not widely available from countries in Africa, Asia, and Central America. The aim of this study is to describe and discuss cancer survival in these regions. Survival analysis was done for 341 658 patients diagnosed with various cancers from 1990 to 2001 and followed up to 2003, from 25 population-based cancer registries in 12 countries in sub-Saharan Africa (The Gambia, Uganda), Central America (Costa Rica), and Asia (China, India, Pakistan, Philippines, Saudi Arabia, Singapore, South Korea, Thailand, Turkey). 5-year age-standardised relative survival (ASRS) and observed survival by clinical extent of disease were determined. For cancers in which prognosis depends on stage at diagnosis, survival was highest in China, South Korea, Singapore, and Turkey and lowest in Uganda and The Gambia. 5-year ASRS ranged from 76-82% for breast cancer, 63-79% for cervical cancer, 71-78% for bladder cancer, and 44-60% for large-bowel cancers in China, Singapore, South Korea, and Turkey. Survival did not exceed 22% for any cancer site in The Gambia; in Uganda, survival did not exceed 13% for any cancer site except breast (46%). Variations in survival correlated with early detection initiatives and level of development of health services. The wide variation in cancer survival between regions emphasises the need for urgent investments in improving awareness, population-based cancer registration, early detection programmes, health-services infrastructure, and human resources. Association for International Cancer Research (AICR; St Andrews, UK), Association pour la Recherche sur le Cancer (ARC, Villejuif, France), and the Bill & Melinda Gates Foundation (Seattle, USA). Copyright 2010 Elsevier Ltd. All rights reserved.

  8. Mercury in Forage Fish from Mexico and Central America: Implications for Fish-Eating Birds.

    Science.gov (United States)

    Elliott, John E; Kirk, David A; Elliott, Kyle H; Dorzinsky, Jessica; Lee, Sandi; Inzunza, Ernesto Ruelas; Cheng, Kimberly M T; Scheuhammer, Tony; Shaw, Patrick

    2015-11-01

    Mercury (Hg) is a global contaminant of aquatic food chains. Aquatic birds, such as the osprey (Pandion haliaetus), with migratory populations breeding in Canada and the northern United States and wintering in the Central and South America, can be exposed to mercury on both the breeding and wintering ranges. We examined Hg levels in 14 fish taxa from 24 osprey wintering sites identified from satellite telemetry. Our main goal was to determine whether fish species that feature in the diet of overwintering and resident fish-eating birds reached toxicity thresholds for Hg. Mean Hg levels in fish whole carcasses ranged from a high of 0.18 µg g(-1) (wet weight) in Scomberomorus sierra to a low of 0.009 µg g(-1) in Catostomidae. Average Hg levels were within published toxicity threshold values in forage fish for only two sites in Mexico (Puerto Vallarta and San Blas Estuary), and all were marine species, such as mackerel (Scomberomorus sierra), sea catfish (Ariopus spp.), and sardinas species (Centropomus spp.). Except for one sample from Nicaragua, sea catfish from Puerto Morazan, none of the fish from sites in Central America had Hg levels which exceeded the thresholds. Nonmetric multidimensional scaling revealed geographical differences in Hg levels with significant pairwise differences between sites along the Pacific Ocean (Mexico) versus the Bay of Campeche, partly due to differences in species composition of sampled fish (and species distributions). Hg increased with trophic level, as assessed by nitrogen stable isotope ratios (δ(15)N but not δ(13)C), in freshwater and marine, but not estuarine, environments. Hg concentrations in forage fish do not account for the elevated Hg reported for many osprey populations on the breeding grounds, thus primary sources of contamination appear to be in the north.

  9. Seismic hazard map of North and Central America and the Caribbean

    Directory of Open Access Journals (Sweden)

    K. M. Shedlock

    1999-06-01

    Full Text Available Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends on reliable estimates of seismic hazard. National, state, and local governments, decision makers, engineers, planners, emergency response organizations, builders, universities, and the general public require seismic hazard estimates for land use planning, improved building design and construction (including adoption of building construction codes, emergency response preparedness plans, economic forecasts, housing and employment decisions, and many more types of risk mitigation. The seismic hazard map of North and Central America and the Caribbean is the concatenation of various national and regional maps, involving a suite of approaches. The combined maps and documentation provide a useful regional seismic hazard framework and serve as a resource for any national or regional agency for further detailed studies applicable to their needs. This seismic hazard map depicts Peak Ground Acceleration (PGA with a 10% chance of exceedance in 50 years. PGA, a short-period ground motion parameter that is proportional to force, is the most commonly mapped ground motion parameter because current building codes that include seismic provisions specify the horizontal force a building should be able to withstand during an earthquake. This seismic hazard map of North and Central America and the Caribbean depicts the likely level of short-period ground motion from earthquakes in a fifty-year window. Short-period ground motions effect short-period structures (e.g., one-to-two story buildings. The highest seismic hazard values in the region generally occur in areas that have been, or are likely to be, the sites of the largest plate boundary earthquakes.

  10. Early Cretaceous gabbroic rocks from the Taihang Mountains: Implications for a paleosubduction-related lithospheric mantle beneath the central North China Craton

    Science.gov (United States)

    Wang, Yuejun; Fan, Weiming; Zhang, Hongfu; Peng, Touping

    2006-02-01

    SHRIMP zircon U-Pb ages and geochemical and Sr-Nd-Pb isotopic data are presented for the gabbroic intrusive from the southern Taihang Mountains to characterize the nature of the Mesozoic lithospheric mantle beneath the central North China Craton (NCC). The gabbroic rocks emplaced at 125 Ma and are composed of plagioclase (40-50%), amphibole (20-30%), clinopyroxene (10-15%), olivine (5-10%) and biotite (5-7%). Olivines have high MgO (Fo = 78-85) and NiO content. Clinopyroxenes are high in MgO and CaO with the dominant ones having the formula of En 42-46Wo 41-50Fs 8-13. Plagioclases are dominantly andesine-labradorite (An = 46-78%) and have normal zonation from bytownite in the core to andesine in the rim. Amphiboles are mainly magnesio and actinolitic hornblende, distinct from those in the Precambrian high-pressure granulites of the NCC. These gabbroic rocks are characterized by high MgO (9.0-11.04%) and SiO 2 (52.66-55.52%), and low Al 2O 3, FeOt and TiO 2, and could be classified as high-mg basaltic andesites. They are enriched in LILEs and LREEs, depleted in HFSEs and HREEs, and exhibit ( 87Sr/ 86Sr) i = 0.70492-0.70539, ɛNd( t) = - 12.47-15.07, ( 206Pb/ 204Pb) i = 16.63-17.10, Δ8/4 = 70.1-107.2 and Δ7/4 = - 2.1 to - 9.4, i.e., an EMI-like isotopic signatures. Such geochemical features indicate that these early Cretaceous gabbroic rocks were originated from a refractory pyroxenitic veined-plus-peridotite source previously modified by an SiO 2-rich melt that may have been derived from Paleoproterozoic subducted crustal materials. Late Mesozoic lithospheric extension might have induced the melting of the metasomatised lithospheric mantle in response to the upwelling of the asthenosphere to generate these gabbroic rocks in the southern Taihang Mountains.

  11. Warm and Dry Spells (WDS in Austral Winter over Central South America

    Directory of Open Access Journals (Sweden)

    P. Satyamurty

    2007-06-01

    Full Text Available The horizontal and vertical structure of unusually warm and dry spells (WDS over the central parts of South America during the winter and post-winter months (JJAS are studied. During WDS the mean temperature and humidity anomalies over central Brazil are about +4.1°C and −13.2%, respectively. The mean duration of WDS is 11 days and their mean frequency is less than one per year during the months of JJAS. Apparently, WDS have no preference for the phase of ENSO. Widespread and persistent subsidence in the middle troposphere is observed in tropical Brazil during WDS, which renders the lower tropospheric air warm and dry. The negative anomalies of the specific humidity are observed to be associated with the subsidence regions. A strong, slow moving ridge in the eastern South Pacific and a low-pressure center in northern Argentina are important surface characteristics during the WDS. A more detailed investigation of two specific WDS events, a strong event (August–September 1999 and a moderate one (June 2002, shows a blocking-like situation in the 500-hPa geopotential and surface pressure fields in the Pacific. The South Atlantic subtropical high somewhat approaches the continent. Strong northerlies over the central and eastern parts of Brazil are also observed in the lower troposphere. During WDS the regional circulation acquires summertime characteristics, except for the absence of precipitation, and the circulation in the meridional plane is in the opposite sense from the Hadley circulation. A frontal system, supported by a 500-hPa trough, advances into central Brazil, causing the dissipation of the anomalous situation.

  12. Catalogo General de Universidades, 1970-1971: Federacion de Universidades Privadas de America Central y Panama (General Catalog of Universities, 1970-1971: Federation of Private Universities of Central America and Panama).

    Science.gov (United States)

    Federacion de Universidades Privadas de America Central y Panama, Guatemala City (Guatemala).

    This document contains the 1970-1971 catalogues of five universities belonging to the Federation of Private Universities of Central America and Panama (FUPAC). The catalogues provide information on university administrators and staff, historical background, admission requirements, degree programs, scholarships, and courses. The catalogues included…

  13. Geoid modeling in Mexico and the collaboration with Central America and the Caribbean.

    Science.gov (United States)

    Avalos, D.; Gomez, R.

    2012-12-01

    The model of geoidal heights for Mexico, named GGM10, is presented as a geodetic tool to support vertical positioning in the context of regional height system unification. It is a purely gravimetric solution computed by the Stokes-Helmert technique in resolution of 2.5 arc minutes. This product from the Instituto Nacional de Estadistica y Geografia (INEGI) is released together with a series of 10 gravimetric models which add to the improvements in description of the gravity field. In the recent years, the INEGI joined the initiative of the U.S. National Geodetic Survey and the Canada's Geodetic Survey Division to promote the regional height system unification. In an effort to further improve the compatibility among national geoid models in the region, the INEGI has begun to champion a network of specialists that includes national representatives from Central America and the Caribbean. Through the opening of opportunities for training and more direct access to international agreements and discussions, the tropical region is gaining participation. Now a significantly increased number of countries is pushing for a future North and Central American geoid-based vertical datum as support of height system unification.eoidal height in Mexico, mapped from the model GGM10.

  14. International relations among Tom Thumbs: Taiwan as provider of aid Central America

    Directory of Open Access Journals (Sweden)

    Francisco Javier Haro Navejas

    2007-06-01

    Full Text Available This paper analyzes the Official Development Aid (AOD that has as its source Taiwan and as its destination Central America. It has three basic aims: Firstly, there is a huge bibliographic vacuum on the topic of these pages. Beginning filling it is an academic need. Even some intellectuals feel that they should lean against either Beijing or Taipei, that if they write on Taiwan they should defend or attack one of the contending parties. Here it is seen that a study close to objectivity is possible. Secondly, most of the research in International Relations has been focused on topics related with power itself or with just elements related with hard power. AOD is both hard and soft power, therefore this paper shades light to the dark side partially viewing international relations from a theoretical perspective were interactions help to construct identities and cooperation is an essential variable of world politics. Finally, it will be seen below that the Taiwanese cooperativeeconomic actions are helpful to the progress of poor parts of the Central American region and are helpful to create domestic markets with strong links with the world market deepening the economic integration both regional and global. Aid from Taiwan and some other countries, mainly through the transmission of know how, could be of assistance in surmounting huge troubles. Aid is vital because some of Central American’s problems are being exported mainly to México and the United States under the form, just to give an example, of Mara Salvatrucha gangs source of violence and drug trafficking. It is not meaningless to stress that Taiwanese ODA is by far not enough and is very small in the international context.

  15. Wave climate and trends in the Pacific region off Mexico and Central America

    Science.gov (United States)

    García-Nava, Héctor; Esquivel-Trava, Bernardo; Ocampo-Torres, Francisco J.

    2017-04-01

    Proper planning of maritime activities strongly depends on the prior knowledge of wave characteristics. In particular, knowledge of wave climate and its variability is essential for offshore and coastal operations and engineering projects. This work describes the wave climate and its variability in the Pacific region off Mexico and Central America (PMCA) based on a 19 years wave hindcast. It is found that the variability of the wave height is dominated by changes of the swell arriving from the North Pacific and of the waves generated in the Gulfs of Tehuantepec and Papagayo. The highest waves in PMCA region are associated with the occurrence of tropical storms however; tropical storms are so sparse in time and space that have little influence in the long-term mean. An analysis of the correlation of the monthly anomaly of wave height with several climate indices suggests that the major source of variability in PMCA region is El Niño Southern Oscillation (ENSO). It is also suggested that, through the Pacific-North America teleconnection, ENSO modifies the storms characteristics over the North Pacific and causes changes in the waves arriving into PMCA region. In PMCA region wave height exhibits a negative trend almost everywhere. Notwithstanding, trends are only statistically significant in regions dominated by swell from the North Pacific, with decreasing rates between -1 to -3 cm.yr-1. This study suggests that the variability of the waves conditions over the North Pacific are related to changes of the strength and position of the Aleutian Low which are evidenced by the behaviour of the Pacific Decadal Oscillation. If this is the case, the observed negative trends are expected to be part of a multi-decadal oscillation rather than a long-term behaviour.

  16. Inner forearc response to subduction of the Panama Fracture Zone, southern Central America

    Science.gov (United States)

    Morell, Kristin D.; Fisher, Donald M.; Gardner, Thomas W.

    2008-01-01

    Subduction of the right-lateral Panama Fracture Zone, along the convergent margin of Central America creates abrupt lateral variations in convergence rate, obliquity, and subducting crustal thickness at its intersection with the Middle America Trench. This intersection, known as the Panama (CO-NZ-CA) Triple Junction, is migrating to the southeast at a rate of 55 mm/yr, and currently coincides with the lateral termination of the Fila Costeña Thrust Belt in the inner forearc of the overriding plate. Mapping in the inner forearc in the area that straddles the subducting Panama Fracture Zone reveals that Cocos-Caribbean convergence west of the triple junction leads to the development of an inner forearc thrust belt inboard of the colliding Cocos Ridge, while little deformation is evident inboard of Nazca-Caribbean convergence, east of the triple junction. This results in the lateral termination of the Fila Costeña Thrust Belt in the region of the forearc that projects over the Panama Fracture Zone, where four out of five mapped thrust faults tip out and are buried by lahars. Three new balanced cross-sections indicate a steep gradient in shortening from the center of the thrust belt to its southeastern termination. The short-term history of the inner forearc recorded in the landscape and topography of the Fila Costeña is consistent with the southeastward migration of the thrust belt and the Panama Triple Junction throughout the past ˜ 3 Ma, with evidence for the growth of a new topographic divide and reorganization of stream channel networks.

  17. Two new genera of metalmark butterflies of North and Central America (Lepidoptera, Riodinidae

    Directory of Open Access Journals (Sweden)

    Marysol Trujano-Ortega

    2018-01-01

    Full Text Available Two new genera of Riodinidae (Insecta: Lepidoptera are described, Neoapodemia Trujano-Ortega, gen. n. (Neoapodemia nais (W. H. Edwards, 1876, comb. n., N. chisosensis Freeman, 1964, comb. n. and Plesioarida Trujano-Ortega & García-Vázquez, gen. n. (Plesioarida palmerii palmerii (W. H. Edwards, 1870, comb. n., P. palmerii arizona (Austin, [1989], comb. n., P. palmerii australis (Austin, [1989], comb. n., P. hepburni hepburni (Godman & Salvin, 1886, comb. n., P. hepburni remota (Austin, 1991, comb. n., P. murphyi (Austin, [1989], comb. n., P. hypoglauca hypoglauca (Godman & Salvin, 1878, comb. n., P. hypoglauca wellingi (Ferris, 1985, comb. n., P. walkeri (Godman & Salvin, 1886, comb. n., P. selvatica (De la Maza & De la Maza, 2017, comb. n.. Neoapodemia Trujano-Ortega, gen. n. is distributed in the southwestern USA and northeastern Mexico, while Plesioarida Trujano-Ortega & García-Vázquez, gen. n. is present from the southern USA to Central America. Species of these genera were previously classified as Apodemia C. Felder & R. Felder but molecular and morphological evidence separate them as new taxa. Morphological diagnoses and descriptions are provided for both new genera, including the main distinctive characters from labial palpi, prothoracic legs, wing venation and genitalia, as well as life history traits. A molecular phylogeny of one mitochondrial gene (COI and two nuclear genes (EF-1a and wg are also presented of most species of Apodemia, Neoapodemia Trujano-Ortega, gen. n., Plesioarida Trujano-Ortega & García-Vázquez, gen. n., and sequences of specimens from all tribes of Riodinidae. We compare the characters of Apodemia, Neoapodemia Trujano-Ortega, gen. n. and Plesioarida Trujano-Ortega & García-Vázquez, gen. n. and discuss the differences that support the description of these new taxa. This is a contribution to the taxonomy of the Riodinidae of North America of which the generic diversity is greater than previously recognized.

  18. Projected impact of twenty-first century ENSO changes on rainfall over Central America and northwest South America from CMIP5 AOGCMs

    Science.gov (United States)

    Steinhoff, Daniel F.; Monaghan, Andrew J.; Clark, Martyn P.

    2015-03-01

    Due to the importance that the El Niño-Southern Oscillation (ENSO) has on rainfall over the tropical Americas, future changes in ENSO characteristics and teleconnections are important for regional hydroclimate. Projected changes to the ENSO mean state and characteristics, and the resulting impacts on rainfall anomalies over Central America, Colombia, and Ecuador during the twenty-first century are explored for several forcing scenarios using a suite of coupled atmosphere-ocean global climate models (AOGCMs) from the fifth phase of the Coupled Model Intercomparison Project (CMIP5). Mean-state warming of eastern tropical Pacific sea surface temperatures, drying of Central America and northern Colombia, and wetting of southwest Colombia and Ecuador are consistent with previous studies that used earlier versions of the AOGCMs. Current and projected future characteristics of ENSO (frequency, duration, amplitude) show a wide range of values across the various AOGCMs. The magnitude of ENSO-related rainfall anomalies are currently underestimated by most of the models, but the model ensembles generally simulate the correct sign of the anomalies across the seasons around the peak ENSO effects. While the models capture the broad present-day ENSO-related rainfall anomalies, there is not a clear sense of projected future changes in the precipitation anomalies.

  19. Hydrological Dynamics of Central America: Time-of-Emergence of the Global Warming Signal

    Science.gov (United States)

    Imbach, P. A.; Georgiou, S.; Calderer, L.; Coto, A.; Nakaegawa, T.; Chou, S. C.; Lyra, A. A.; Hidalgo, H. G.; Ciais, P.

    2016-12-01

    Central America is among the world's most vulnerable regions to climate variability and change. Country economies are highly dependent on the agricultural sector and over 40 million people's rural livelihoods directly depend on the use of natural resources. Future climate scenarios show a drier outlook (higher temperatures and lower precipitation) over a region where rural livelihoods are already compromised by water availability and climate variability. Previous efforts to validate modelling of the regional hydrology have been based on high resolution (1 km2) equilibrium models (Imbach et al., 2010) or using dynamic models (Variable Infiltration Capacity) with coarse climate forcing (0.5°) (Hidalgo et al., 2013; Maurer et al., 2009). We present here: (i) validation of the hydrological outputs from high-resolution simulations (10 km2) of a dynamic vegetation model (Orchidee), using 7 different sets of model input forcing data, with monthly runoff observations from 182 catchments across Central America; (ii) the first assessments of the region's hydrological variability using the historical simulations (iii) an estimation of the time of emergence of the climate change signal (under the SRES emission scenarios) on the water balance. We found model performance to be comparable with that from studies in other world regions (Yang et al. 2016) when forced with high resolution precipitation data (monthly values at 5 km2, Funk et al. (2015)) and the Climate Research Unit (CRU 3.2, Harris et al. (2014)) dataset of meteorological parameters. Validation results showed a Pearson correlation coefficient ≈ 0.6, general underestimation of runoff of ≈ 60% and variability close to observed values (ratio of standard deviations of ≈ 0.7). Maps of historical runoff are presented to show areas where high runoff variability follows high mean annual runoff, with opposite trends over the Caribbean. Future scenarios show large areas where future maximum water availability will

  20. Detrital zircon geochronology of quartzose metasedimentary rocks from parautochthonous North America, east-central Alaska

    Science.gov (United States)

    Dusel-Bacon, Cynthia; Holm-Denoma, Christopher S.; Jones, James V.; Aleinikoff, John N.; Mortensen, James K.

    2017-01-01

    We report eight new U-Pb detrital zircon ages for quartzose metasedimentary rocks from four lithotectonic units of parautochthonous North America in east-central Alaska: the Healy schist, Keevy Peak Formation, and Sheep Creek Member of the Totatlanika Schist in the northern Alaska Range, and the Butte assemblage in the northwestern Yukon-Tanana Upland. Excepting 1 of 3 samples from the Healy schist, all have dominant detrital zircon populations of 1.9–1.8 Ga and a subordinate population of 2.7–2.6 Ga. Three zircons from Totatlanika Schist yield the youngest age of ca. 780 Ma. The anomalous Healy schist sample has abundant 1.6–0.9 Ga detrital zircon, as well as populations at 2.0–1.8 Ga and 2.7–2.5 Ga that overlap the ages from the rest of our samples; it has a minimum age population of ca. 1007 Ma.Detrital zircon age populations from all but the anomalous sample are statistically similar to those from (1) other peri-Laurentian units in east-central Alaska; (2) the Snowcap assemblage in Yukon, basement of the allochthonous Yukon-Tanana terrane; (3) Neoproterozoic to Ordovician Laurentian passive margin strata in southern British Columbia, Canada; and (4) Proterozoic Laurentian Sequence C strata of northwestern Canada. Recycling of zircon from the Paleoproterozoic Great Bear magmatic zone in the Wopmay orogen and its Archean precursors could explain both the Precambrian zircon populations and arc trace element signatures of our samples. Zircon from the anomalous Healy schist sample resembles that in Nation River Formation and Adams Argillite in eastern Alaska, suggesting recycling of detritus in those units.

  1. Intellectual property and access to medicines: an analysis of legislation in Central America.

    Science.gov (United States)

    Cerón, Alejandro; Godoy, Angelina Snodgrass

    2009-10-01

    Globalization of intellectual property (IP) protection for medicines has been advancing during the past decade. Countries are obliged to adapt their legislation as a requirement of their membership to the World Trade Organization or as a condition of being part of international trade agreements. There is a growing recognition that, in low-income countries, stronger IP protection is a barrier to access to medicines. At the same time, the number of low-income countries writing national legislation to protect IP for pharmaceutical products is growing worldwide, but little research has been done on the ways in which this process is happening at the national level. This paper aims to contribute to the understanding of the implementation of IP legislation at the national level by providing a comparative analysis of the countries that are part of the United States-Dominican Republic-Central America Free Trade Agreement (DR-CAFTA). The analysis shows three trends. First, countries have often implemented stronger IP protection than required by trade agreements. Second, some countries have adopted IP protection before signing the trade agreements. Third, the process of ratification of DR-CAFTA increased public debate around these issues, which in some cases led to IP legislation that considers public health needs. These trends suggest that industrialized countries and the pharmaceutical industry are using more tactics than just trade agreements to push for increased IP protection and that the process of national legislation is a valid arena for confronting public health needs to those of the industry.

  2. Morphometric analysis of El Salvador Fault Zone. Implications to the tectonic evolution. Central America.

    Science.gov (United States)

    Alonso-Henar, Jorge; Jesús Martínez-Díaz, José; Álvarez-Gómez, José Antonio

    2013-04-01

    It is considered that the study of the recent topography development, and the use of geomorphological indexes are good tools for the quantification of the active tectonics. We have used quantitative geomorphology in order to improve our understanding of the recent activity and tectonic evolution of the El Salvador Fault Zone (ESFZ); an E-W oriented strike-slip fault zone that extends 150 km through El Salvador (Martínez-Díaz et al. 2004). Previous studies propose a transtensive tectonic regime at the Central America Volcanic Arc in El Salvador, which induces relative vertical motions on the faults within El Salvador Fault Zone (i.e. Álvarez-Gómez et al., 2008, Cáceres et al. 2005,). This relative vertical displacement can be quantified with the use of hypsometry as a geomorphological character. The morphometric analysis done contributes to a better understanding of the ESFZ. We have defined km scale tectonic block relative displacements that may be useful to constrain the strain distribution along the ESFZ, length of segments with homogeneous vertical movements and lateral relay of active structures. This study supports the hypothesis of a recent migration in the maximum shortening direction, and the accomodation of the current deformation through the reactivation of pre-existing structures inherited from a previous tectonic frame. A similar tectonic evolution as described Weinberg (1992) in Nicaragua, is interpreted from the results of this study.

  3. Tomographic Inversion for Shear Velocity Beneath the North American Plate

    Science.gov (United States)

    Grand, Stephen P.

    1987-12-01

    A tomographic back projection scheme has been applied to S and SS travel times to invert for shear velocity below the North American plate. The data range in distance from 8° to 80°, and a total of 3923 arrival times were used. First arrivals were measured directly off the seismograms, while the arrival times of later arrivals were found by a waveform correlation technique using synthetic seismograms. The starting model was laterally heterogeneous in the upper 400 km to account for the first-order differences in ray paths already known. The model was divided into blocks with horizontal dimensions of 500 km by 500 km and varying vertical thicknesses. Good resolution was obtained for structure from just below the crust to about 1700 km depth in the mantle. In the upper mantle a high-velocity root was found directly beneath the Canadian shield to about 400 km depth with the Superior province having the highest velocity and deepest root. The east coast of the United States was found to have intermediate velocities from 100 to 350 km depth and the western United States the slowest velocities at these depths. Below 400 km depth the most significant structure found is a slab-shaped high-velocity anomaly from the eastern Carribean to the northern United States. Beneath the Carribean this anomaly is almost vertical and extends from about 700 km to 1700 km depth. Further to the north, the anomaly dips to the east with high velocities at 700 km depth in the central United States and high velocities below 1100 km depth beneath the east coast. The anomaly is about 1% in magnitude. This lower-mantle anomaly may be associated with past subduction of the Farallon plate beneath North America.

  4. Geomorphological impact on agroforestry systems in the interior highlands of Nicaragua, Central America

    Science.gov (United States)

    Mentler, Axel; Wriessnig, Karin; Ottner, Franz; Schomakers, Jasmin; Benavides González, Álvaro; Cisne Contreras, José Dolores; Querol Lipcovich, Daniel

    2013-04-01

    Cerro el Castillo is located in the NW of Nicaragua, Central America, close to the border of Honduras (Provincia Central de las Cordilleras) at 1000-1200m above sea level. In this region, small and medium-sized farms are agroforestry systems with mangos, avocados, coffee, papayas, bananas, strawberries, maize, pumpkins, beans and other vegetables. The production systems are strongly linked to facilities for raising small domestic animals and cows. Main regional agricultural production problems are steep slopes, soil erosion, varying precipitation and distribution, water management and the unstable family income. An investigation of topsoil properties with comparable management systems showed on small scales significant differences in key values of soil chemistry and mineralogy. The outline of the analytical parameters included determination of pH, electrical conductivity (EC), cation exchange capacity (CEC), organic carbon (TOC), dissolved organic carbon (DOC), total nitrogen (TN) and dissolved nitrogen (DN) in soil solution, and plant available nutrients (P and K). The soil's mineralogical composition was determined by X-ray diffraction analysis. The area is a highly weathered karst landscape within a tropical limestone region displaying different amounts of volcanic pyroclastic parent material. The dominant Nitisoils and Andosols show degraded argic and andic horizons along the upper half of the mountainside. The pH values in the topsoil are moderate from pH 5.0 to 5.6. The upland topsoil is decalcified and the amount of plant available phosphorous is very low with significant low Ca concentration at the sorption complex. The mineralogical composition points to the high weathering intensity of this area (high content of kaolinite and a lower concentration of potassium and plagioclase feldspars and andesite). Along the upper half of the mountain, the soil profiles show wider C:N ratios and lower amounts of organic matter. Topsoil at lower altitude and with a lower

  5. Why is Liberal Peace-building so Difficult? Some Lessons from Central America

    Directory of Open Access Journals (Sweden)

    Sabine Kurtenbach

    2010-04-01

    Full Text Available According to the liberal peace-building paradigm the termination of war is a window of opportunity for fundamental change. Central America has been one of the first laboratories of international policies promoting the threefold transformation process of pacification, democratization and economic liberalization. Although none of the postwar countries (Nicaragua, El Salvador, Guatemala slipped back into war, serious deficits abound that can neither be explained as mere consequences of war nor as ‘normal’ developmental problems. The paper introduces an analytical framework locating these problems at the intersection between external influences, societal foundations, consequences of war and violence as well as peace-building. The comparative analysis of the three transformation processes – democratization, market economy and pacification – shows how path dependent patterns remain dominant while reform processes are fragile. This allows for an explanation of common features as well as differences inside the region. Resumen: ¿Por qué es tan difícil la construcción de una paz liberal? Algunas lecciones de América CentralDe acuerdo al paradigma liberal sobre la construcción de la paz, el fin de una guerra abre un abanico de oportunidades para introducir cambios fundamentales. América Central fue uno de los primeros laboratorios donde se aplicaron políticas internacionales que fomentaban el triple proceso de transformación compuesto por la pacificación, la democratización y la liberalización económica. Aunque ninguna de las sociedades de posguerra (Nicaragua, El Salvador, Guatemala volvió a recaer en ella, abundan graves deficiencias que no se pueden explicar ni como meras consecuencias del conflicto ni como problemas ‘normales’ de países en desarrollo. El artículo define un marco analítico que localiza estos problemas en la intersección de influencias externas, bases sociales, consecuencias de la guerra y violencia as

  6. Soil water storage and groundwater behaviour in a catenary sequence beneath forest in central Amazonia: I. Comparisons between plateau, slope and valley floor

    Directory of Open Access Journals (Sweden)

    M. G. Hodnett

    1997-01-01

    Full Text Available Soil water storage was monitored in three landscape elements in the forest (plateau, slope and valley floor over a 3 year period to identify differences in sub-surface hydrological response. Under the plateau and slope, the changes of storage were very similar and there was no indication of surface runoff on the slope. The mean maximum seasonal storage change was 156 mm in the 2 m profile but it was clear that, in the dry season, the forest was able to take up water from below 3.6 m. Soil water availability was low. Soil water storage changes in the valley were dominated by the behaviour of a shallow water table which, in normal years, varied between 0.1 m below the surface at the end of the wet season and 0.8 m at the end of the dry season. Soil water storage changes were small because root uptake was largely replenished by groundwater flow towards the stream. The groundwater behaviour is controlled mainly by the deep drainage from beneath the plateau and slope areas. The groundwater gradient beneath the slope indicated that recharge beneath the plateau and slope commences only after the soil water deficits from the previous dry season have been replenished. Following a wet season with little recharge, the water table fell, ceasing to influence the valley soil water storage, and the stream dried up. The plateau and slope, a zone of very high porosity between 0.4 and 1.1 m, underlain by a less conductive layer, is a probable route for interflow during, and for a few hours after, heavy and prolonged rainfall.

  7. Tsunami hazard assessment in El Salvador, Central America, from seismic sources through flooding numerical models.

    Science.gov (United States)

    Álvarez-Gómez, J. A.; Aniel-Quiroga, Í.; Gutiérrez-Gutiérrez, O. Q.; Larreynaga, J.; González, M.; Castro, M.; Gavidia, F.; Aguirre-Ayerbe, I.; González-Riancho, P.; Carreño, E.

    2013-11-01

    El Salvador is the smallest and most densely populated country in Central America; its coast has an approximate length of 320 km, 29 municipalities and more than 700 000 inhabitants. In El Salvador there were 15 recorded tsunamis between 1859 and 2012, 3 of them causing damages and resulting in hundreds of victims. Hazard assessment is commonly based on propagation numerical models for earthquake-generated tsunamis and can be approached through both probabilistic and deterministic methods. A deterministic approximation has been applied in this study as it provides essential information for coastal planning and management. The objective of the research was twofold: on the one hand the characterization of the threat over the entire coast of El Salvador, and on the other the computation of flooding maps for the three main localities of the Salvadorian coast. For the latter we developed high-resolution flooding models. For the former, due to the extension of the coastal area, we computed maximum elevation maps, and from the elevation in the near shore we computed an estimation of the run-up and the flooded area using empirical relations. We have considered local sources located in the Middle America Trench, characterized seismotectonically, and distant sources in the rest of Pacific Basin, using historical and recent earthquakes and tsunamis. We used a hybrid finite differences-finite volumes numerical model in this work, based on the linear and non-linear shallow water equations, to simulate a total of 24 earthquake-generated tsunami scenarios. Our results show that at the western Salvadorian coast, run-up values higher than 5 m are common, while in the eastern area, approximately from La Libertad to the Gulf of Fonseca, the run-up values are lower. The more exposed areas to flooding are the lowlands in the Lempa River delta and the Barra de Santiago Western Plains. The results of the empirical approximation used for the whole country are similar to the results

  8. Mantle structure beneath the western United States and its implications for convection processes

    Science.gov (United States)

    Xue, Mei; Allen, Richard M.

    2010-07-01

    We present tomographic images of the mantle structure beneath the western United States. Our Dynamic North America Models of P and S velocity structure (DNA07-P and DNA07-S) use teleseismic body waves recorded at ˜600 seismic stations provided by the Earthscope Transportable Array and regional networks. DNA07-P and -S benefit from the unprecedented aperture of the network while maintaining a dense station distribution providing high-resolution body wave imaging of features through the transition zone and into the lower mantle. The main features imaged include (1) the Juan de Fuca subduction system that bottoms at ˜400 km beneath Oregon, implying interaction with the Yellowstone anomaly; (2) a low-velocity conduit beneath Yellowstone National Park that bottoms at 500 km and dips toward the northwest; (3) shallow low-velocity anomalies (upper 200 km) beneath the eastern Snake River Plain (ESRP) and the High Lava Plains, and a deep low-velocity anomaly (>600 km) beneath the ESRP but not Newberry; (4) a low-velocity "slab gap" to ˜400 km depth immediately south of the Mendocino Triple Junction and south of the Gorda slab; and (5) high-velocity "drips" beneath the Transverse Ranges, the southern Central Valley/Sierra Nevada, and central Nevada. These observations reveal extremely heterogeneous mantle structure for the western United States and suggest that we are only just beginning to image the complex interactions between geologic objects. The transportable array allows for analysis of the relationships between these anomalies in an internally consistent single tomographic model. The DNA velocity models are available for download and slicing at http://dna.berkeley.edu.

  9. Large scale patterns of genetic variation and differentiation in sugar maple from tropical Central America to temperate North America.

    Science.gov (United States)

    Vargas-Rodriguez, Yalma L; Platt, William J; Urbatsch, Lowell E; Foltz, David W

    2015-11-19

    Geological events in the latter Cenozoic have influenced the distribution, abundance and genetic structure of tree populations in temperate and tropical North America. The biogeographical history of temperate vegetation that spans large ranges of latitude is complex, involving multiple latitudinal shifts that might have occurred via different migration routes. We determined the regional structuring of genetic variation of sugar maple (Acer saccharum subsp. saccharum) and its only subspecies in tropical America (Acer saccharum subsp. skutchii) using nuclear and chloroplast data. The studied populations span a geographic range from Maine, USA (46°N), to El Progreso, Guatemala (15°N). We examined genetic subdivisions, explored the locations of ancestral haplotypes, analyzed genetic data to explore the presence of a single or multiple glacial refugia, and tested whether genetic lineages are temporally consistent with a Pleistocene or older divergence. Nuclear and chloroplast data indicated that populations in midwestern USA and western Mexico were highly differentiated from populations in the rest of the sites. The time of the most recent common ancestor of the western Mexico haplotype lineage was dated to the Pliocene (5.9 Ma, 95% HPD: 4.3-7.3 Ma). Splits during the Pleistocene separated the rest of the phylogroups. The most frequent and widespread haplotype occurred in half of the sites (Guatemala, eastern Mexico, southeastern USA, and Ohio). Our data also suggested that multiple Pleistocene refugia (tropics-southeastern USA, midwestern, and northeastern USA), but not western Mexico (Jalisco), contributed to post-glacial northward expansion of ranges. Current southern Mexican and Guatemalan populations have reduced population sizes, genetic bottlenecks and tend toward homozygosity, as indicated using nuclear and chloroplast markers. The divergence of western Mexican populations from the rest of the sugar maples likely resulted from orographic and volcanic barriers

  10. Correlation of proterozoic sediments of Western and Central Africa and South America based upon radiochronological and paleontological data

    International Nuclear Information System (INIS)

    Bonhomme, M.G.

    1982-01-01

    Nearly 70 new Rb-Sr isochron ages and many K-Ar conventional ages have been determined between 1975 and 1980 on Proterozoic sedimentary or metasedimentary sequences in western and Central Africa and South America. Some stratigraphic results have been established: (1) five formations have been dated of the Lower Proterozoic; (2) a long sedimentation gap occurs, mainly in western Africa and in some regions of Central Africa and South America between nearly 1600 and 1100 Ma; (3) the upper Riphean assemblages of stromatolites have been dated and compared to those of the Eurasian craton; (4) two main glacial events have been dated, the first one placed at ca. 950 Ma, the second during the Vendian, at ca. 650-620 Ma; (5) it can be stated that, when applied to Precambrian sequences, all stratigraphic methods must be used together. (Auth.)

  11. Offspring production in three freshwater crab species (Brachyura: Pseudothelphusidae from the Amazon region and Central America

    Directory of Open Access Journals (Sweden)

    Ingo S. Wehrtmann

    2010-01-01

    Full Text Available Freshwater crabs are an important component of the fauna of limnic environments, and out of the two true freshwater crab families present in the Neotropics, Pseudothelphusidae is the most diverse. Considering the lack of information regarding reproductive features of neotropical freshwater crabs, we studied, for the first time, the fecundity and the presence of juveniles carried by females of two pseudothelphusids from the Amazon region - Kingsleya latifrons (Randall, 1840 and Kingsleya ytupora Magalhães, 1986 - and one from Central America - Potamocarcinus magnus (Rathbun, 1896. The two Kingsleya species produced relatively few (56-114 and large eggs (1.9-3.7 mm, typical for species with an abbreviated or direct development. Recently produced eggs were substantially larger in K. latifrons (mean 2.83 mm when compared to those of K. ytupora (mean 1.87 mm; however, at the end of the embryogenesis, mean egg diameter was similar in both species. Therefore, it is assumed that hatchlings in both species should have a similar size. A brief description of attached juveniles of K. ytupora is provided. The number of juveniles varied between 30 (K. ytupora and 179 (P. magnus; two size groups of juveniles were found, which indicates that the offspring cling to their mother for a prolonged period of time. There was no significant loss of eggs and juveniles; it is assumed that parental care diminishes the loss of their offspring. We compiled the available information of reproductive aspects from freshwater crabs: egg diameter was in the range of 2-3 mm, independent of female size and fecundity, and reported egg number varied between 9 and 417 eggs.

  12. Atmospheric circulation associated with extreme generalized frosts persistence in central-southern South America

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Gabriela V. [Centro de Investigaciones Cientificas y Transferencia de Tecnologia a la Produccion, Diamante (CICYTTTP-CONICET), Diamante, Entre Rios (Argentina); Berri, Guillermo J. [Servicio Meteorologico Nacional - CONICET, Buenos Aires (Argentina)

    2012-03-15

    Generalized frosts (GF) in central-southern South America have a strong impact due to their spatial extension, and they are especially important when they become persistent. This paper aims at identifying the atmospheric circulation features that determine the extreme GF persistence, i.e. very persistent and without persistence, and the differences between them, during the 1961-1990 winters. Since the GF without persistence group outnumbers the other one, two subgroups are composed with events selected from winters with maximum and minimum frequency of GF occurrence, respectively. Additionally, the individual event of July 1988 within the very persistent GF group is analyzed due to its exceptional persistence. GF persistence is mainly conditioned by two large-scale dynamic factors. One is the Rossby wave train propagation across the Pacific Ocean, and the other one is the location with respect to the continent and the magnitude of the confluence in the jet entrance region in subtropical latitudes. A predominantly meridional Rossby wave train propagation with a confluence region to the west of the continent prior to the event favors GF with intermediate (null) persistence depending on the greater (lesser) jet acceleration. This is conditioned by the magnitude of the confluence, which, in turn, depends on the disposition of the wave train propagation pattern. Instead, an essentially zonal propagation with a confluence region to the east of the continent favors the GF persistence for several days, yet if there is no confluence the event does not persist. The greatest persistence of an event combines the confluence/diffluence of the jet entrance/exit region, which depends on the disposition with respect to the continent of the zonally propagating Rossby wave trains. (orig.)

  13. Emerging deforestation trends in tropical dry forests ecoregions of Mexico and Central America

    Science.gov (United States)

    Portillo, C. A.; Cao, G.; Smith, V.

    2015-12-01

    Neotropical dry forests (TDF) have experienced an unprecedented deforestation that is leading to the loss of tropical biodiversity at a rapid pace, but information on deforestation dynamics in TDF is scarce. In this study, we present a sub-continental and national level assessment of TDF loss patterns in Mexico and Central America at high spatial and temporal resolution using remote sensing and GIS technologies. We used the Global Forest Change (GFC) dataset published by Hansen et al. (2013) which shows results from time-series analysis of Landsat images in characterizing global forest extent and change from 2000 through 2013. We analyzed forest loss within and around mapped TDF cover mapped by Portillo-Quintero et al. 2010. In order to minimize errors in source data, we overlaid a 25 x 25 km grid on top of the regional dataset and conducted a cell by cell and country by country inspection at multiple scales using high resolution ancillary data. We identified trends in the clustering of space-time TDF deforestation data using ArcGIS, categorizing trends in: new, consecutive, intensifying, persistent, diminishing, sporadic, oscillating and historical hotspots (high frequency of deforestation events) and cold spots (low frequency of deforestation). In general, the region is experiencing less frequent deforestation events with a higher number of intensifying and new cold spots across TDF landscapes. However, an important number of intensifying and persistent hotspots exist so no general trend in forest loss was detected for the period 2001-2013, except for El Salvador which shows a significant decreasing trend in forest loss. Mexico, Nicaragua, Honduras and Guatemala are the major sources of intensifying, persistent and new deforestation hot spots. These were identified in the southern pacific coast and the Yucatan Peninsula in Mexico, northwestern Guatemala, both western and eastern Honduras and around Lake Nicaragua in Nicaragua.

  14. Phylogenetics of Ogyges Kaup and the biogeography of Nuclear Central America (Coleoptera, Passalidae)

    Science.gov (United States)

    Cano, Enio B.; Schuster, Jack C.; Morrone, Juan J.

    2018-01-01

    Abstract A phylogenetic morphological analysis of the genus Ogyges Kaup, distributed in Nuclear Central America, from Chiapas, Mexico, to northwestern Nicaragua was undertaken. Five species of Proculejus Kaup, distributed north of the Isthmus of Tehuantepec in Mexico, were selected as outgroup. Ogyges was recovered as monophyletic with three species groups: championi, laevissimus, and crassulus. Each species group shows a distinct, generally allopatric distribution. The O. championi species group, with ten species, is distributed in the Maya block, more specifically in the mountainous system north of the Motozintla-Comaltitlán fault in Chiapas, and north of the dry valleys of the Cuilco and Motagua rivers in Guatemala. The two remaining species groups are distributed in the Chortis block. The O. laevissimus species group, including seven species, ranges mostly along the Pacific Volcanic Chain from Guatemala to El Salvador, and from southeastern Honduras to the northwestern area of Nicaragua. The O. crassulus species group, with ten species, is distributed from northeastern Guatemala (Merendón) to northern Honduras. The Isthmus of Tehuantepec in Mexico, the Motagua-Cuilco and Motozintla-Comaltitlán sutures zones in Chiapas and Guatemala, the lowland valleys of Colón and Comalí rivers between Nicaragua and Honduras (or, perhaps, the northern suture of the Siuna Terrane in Nicaragua), the Guayape fault system in Honduras, and the intricate dry valleys of Ulúa-Chamelecón-Olancho in Honduras, are hypothesized to have acted as barriers that affected the geographical distribution of Ogyges, as well as probably other montane organisms. PMID:29674874

  15. A new species of arboreal pitviper from the Atlantic versant of northern Central America

    Directory of Open Access Journals (Sweden)

    Jonathan A Campbell

    2000-12-01

    Full Text Available A new species of green, prehensile-tailed pitviper of the genus Bothriechis is described from the Atlantic slopes of eastern Guatemala and western Honduras. This species appears to be most closely related to B. bicolor of the Pacific versant of Chiapas (Mexico and Guatemala. Several other species of Bothriechis occur on the Atlantic versant of northern Central America, including two montane species, B. aurifer and B. marchi but, with one possible exception, these are not known to be sympatric with the new species and occur in different mountain ranges. The widespread B. schlegelii occurs up to at least 900 m on the Sierra de Caral, where the lowest elevation recorded for the new species is 885 m.Se describe una nueva especie de víbora de foseta, verde, arborícola y de cola prensil, del género Bothriechis. Esta nueva especie se encuentra en las laderas boscosas de la vertiente Atlántica del Este de Guatemala y el Oeste de Honduras, y al parecer está cercanamente relacionada a B. bicolor, de la vertiente Pacífica de Chiapas (México y Guatemala. Algunas otras especies de Bothriechis también habitan la vertiente Atlántica del norte de Centro América, incluyendo dos especies montanas, B. aurifer y B. marchi. Sin embargo, estas dos especies no ocurren en simpatría con la nueva especie, e incluso, habitan distintos sistemas montañosos. La especie de distribución más amplia, B. schlegelii, sí ocurre en simpatría con la nueva especie en la Sierra de Caral, a 900 m sobre el nivel del mar.

  16. [Agrarian movements, development alternatives and food security in Central America: scenarios of transition].

    Science.gov (United States)

    Rodriguez Rojas, R

    1991-01-01

    This article, based on personal experiences with a network of organizations of small and medium agricultural producers in Central America, aims to present the views of peasant organizations concerning agrarian problems in the region. The 3 major sections of work define the place of peasant agriculture in the traditional agrarian structure and the new problems resulting from the structural adjustment programs of the 1980s; separately describe the new peasant movements emerging in Honduras, El Salvador, Nicaragua, Costa Rica, and Panama, identifying common themes an efforts at international collaboration; and explore the positions of the peasant organizations on the optimal strategies for agricultural development and agrarian change. Agriculture remains the backbone of the Central American economies. But because the economic model in the region is 1 of accumulation characterized by dependency, concentration of capital, and social marginalization, the agrarian structure is at the basis of social tensions. Efforts to develop peasant agriculture and to give small producers access to marketing and credit services have been weak and sporadic. The new peasant movements are less inclined than those of the past to employ tactics of confrontation in their efforts to secure access to land and better working conditions. The new movement is the expression of small market producers sometimes grouped into associations who are oriented to production of basic foodstuffs for the internal market. A new concern with adaptation and negotiation is evident. The new organizations have in common a belief in their ability to propose new solutions to regional problems. Their views are founded on a positive assessment of the ability of peasant agriculture to produce food and add dynamism to the regional economy after barriers to credit, technological progress, and modernization in general are removed. Signs of increased cooperation are evident between peasant organizations and other groups

  17. Medicinal Plants from North and Central America and the Caribbean Considered Toxic for Humans: The Other Side of the Coin

    OpenAIRE

    Alonso-Castro, Angel Josabad; Domínguez, Fabiola; Ruiz-Padilla, Alan Joel; Campos-Xolalpa, Nimsi; Zapata-Morales, Juan Ramón; Carranza-Alvarez, Candy; Maldonado-Miranda, Juan Jose

    2017-01-01

    The consumption of medicinal plants has notably increased over the past two decades. People consider herbal products as safe because of their natural origin, without taking into consideration whether these plants contain a toxic principle. This represents a serious health problem. A bibliographic search was carried out using published scientific material on native plants from Mexico, Central America, and the Caribbean, which describe the ethnobotanical and toxicological information of medicin...

  18. Information to Act: Household Characteristics are Predictors of Domestic Infestation with the Chagas Vector Triatoma dimidiata in Central America

    OpenAIRE

    Zamora, Dulce María Bustamante; Hernández, Marianela Menes; Torres, Nuria; Zúniga, Concepción; Sosa, Wilfredo; de Abrego, Vianney; Escobar, María Carlota Monroy

    2015-01-01

    The interruption of vectorial transmission of Chagas disease by Triatoma dimidiata in central America is a public health challenge that cannot be resolved by insecticide application alone. In this study, we collected information on previously known household risk factors for infestation in 11 villages and more than 2,000 houses in Guatemala, Honduras, and El Salvador, and we constructed multivariate models and used multimodel inference to evaluate their importance as predictors of infestation...

  19. Active mountain building and the distribution of “core” Maxillariinae species in tropical Mexico and Central America

    Science.gov (United States)

    Kirby, Stephen H.

    2011-01-01

    The observation that southeastern Central America is a hotspot for orchid diversity has long been known and confirmed by recent systematic studies and checklists. An analysis of the geographic and elevation distribution demonstrates that the most widespread species of “core” Maxillariinae are all adapted to life near sea level, whereas the most narrowly endemic species are largely distributed in wet highland environments. Drier, hotter lowland gaps exist between these cordilleras and evidently restrict the dispersal of the species adapted to wetter, cooler conditions. Among the recent generic realignments of “core” Maxillariinae based on molecular phylogenetics, the Camaridium clade is easily the most prominent genus in Central America and is largely restricted to the highlands of Costa Rica and Panama, indicating that this region is the ancestral home of this genus and that its dispersal limits are drier, lowland cordilleran gaps. The mountains of Costa Rica and Panama are among the geologically youngest topographic features in the Neotropics, reflecting the complex and dynamic interactions of numerous tectonic plates. From consideration of the available geological evidence, I conclude that the rapid growth of the mountain ranges in Costa Rica and Panama during the late Cenozoic times created, in turn, very rapid ranges in ecological life zones and geographic isolation in that part of the isthmus. Thus, I suggest that these recent geologic events were the primary drivers for accelerated orchid evolution in southeastern Central America.

  20. Active fault characterization throughout the Caribbean and Central America for seismic hazard modeling

    Science.gov (United States)

    Styron, Richard; Pagani, Marco; Garcia, Julio

    2017-04-01

    The region encompassing Central America and the Caribbean is tectonically complex, defined by the Caribbean plate's interactions with the North American, South American and Cocos plates. Though active deformation over much of the region has received at least cursory investigation the past 50 years, the area is chronically understudied and lacks a modern, synoptic characterization. Regardless, the level of risk in the region - as dramatically demonstrated by the 2010 Haiti earthquake - remains high because of high-vulnerability buildings and dense urban areas home to over 100 million people, who are concentrated near plate boundaries and other major structures. As part of a broader program to study seismic hazard worldwide, the Global Earthquake Model Foundation is currently working to quantify seismic hazard in the region. To this end, we are compiling a database of active faults throughout the region that will be integrated into similar models as recently done in South America. Our initial compilation hosts about 180 fault traces in the region. The faults show a wide range of characteristics, reflecting the diverse styles of plate boundary and plate-margin deformation observed. Regional deformation ranges from highly localized faulting along well-defined strike-slip faults to broad zones of distributed normal or thrust faulting, and from readily-observable yet slowly-slipping structures to inferred faults with geodetically-measured slip rates >10 mm/yr but essentially no geomorphic expression. Furthermore, primary structures such as the Motagua-Polochic Fault Zone (the strike-slip plate boundary between the North American and Caribbean plates in Guatemala) display strong along-strike slip rate gradients, and many other structures are undersea for most or all of their length. A thorough assessment of seismic hazard in the region will require the integration of a range of datasets and techniques and a comprehensive characterization of epistemic uncertainties driving

  1. Food Security and Extreme Events: Evidence from Smallholder Farmers in Central America

    Science.gov (United States)

    Saborio-Rodriguez, M.; Alpizar, F.; Harvey, C.; Martinez, R.; Vignola, R.; Viguera, B.; Capitan, T.

    2016-12-01

    Extreme weather events, which are expected to increase in magnitude and frequency due to climate change, are one of the main threats for smallholder farmers in Central America. Using a rich dataset from carefully selected subsistence farm households, we explore the determinants and severity of food insecurity resulting from extreme hydrometeorological hazards. In addition, we analyze farmerś coping strategies. Our analysis sheds light over food insecurity as an expression of vulnerability in a region that is expected to be increasingly exposed to extreme events and in a population already stressed by poverty and lack of opportunities. Regarding food insecurity, multivariate analyses indicate that education, having at least one migrant in the household, labor allocation, number of plots, and producing coffee are determinants of the probability of experiencing lack of food after an extreme weather event. Once the household is lacking food, the duration of the episode is related to access to credit, number of plots, producing coffee, ownership of land and gender of the head of the household. This results are in line with previous literature on the determinants of food insecurity in particular, and vulnerability, in general. Our dataset also allows us to analyze coping strategies. Households experiencing lack of food after an extreme weather event report mainly changes in their habits, as decreasing the amount of food consumed (54%) and modifying their diet (35%). A low proportion of household (between 10% and 15%, depending on the nature of the event) use their assets, by redirecting their savings, migrating, and selling items from the house. Asking money or food from family and friends or from an organization is reported for 4% of the households. This general results are connected to the specific coping strategies related to damages in crops, which are explored in detail. Our results indicate that there are patterns among the household experiencing lack of food

  2. Conference report on tobacco taxes in Central America: current situation and opportunities to reduce prevalence and increase fiscal revenues.

    Science.gov (United States)

    Garcés, Ana; Garcés, Miguel; Barnoya, Joaquin; Cabrera, Maynor; Sandoval, Rosa; Orozco, Juan Guillermo; Chaloupka, Frank J

    2014-01-01

    As stated in Article 6 of Framework Convention on Tobacco Control (FCTC), increasing tobacco prices through higher taxes is one of the most effective interventions to reduce tobacco use and to encourage smokers to quit. The potential for tax increases on tobacco products in Central America is ample. We aim to synthesize the current tobacco taxes situation and highlight research needs to strengthen taxation. In May 2012, a workshop was carried out with representatives from each Central American country to analyze the tobacco tax situation in each country and to identify key research gaps with experts in the field. Tobacco taxes in Central America fall far short of the levels recommended by FCTC. Moreover, the legal framework is complex and creates barriers for higher taxes that require further research and political will. Top research priorities are an in-depth analysis of tobacco tax legislation, impact of tax and price policies, analysis of costs associated to health care of tobacco-related diseases and lost productivity, and the feasibility of approaches to increasing tobacco taxes in certain contexts. An additional area of research is the interrelationship between human rights and tobacco control. Central American countries would benefit from increasing excise taxes on tobacco products. The lack of available data and research to counteract tobacco industry arguments are significant obstacles. Active leadership of civil society in support of the partnership of chronic disease interventions is vital in order to obtain tax increases on tobacco products.

  3. Central Bank independence in Latin America La independencia de la Banca Central en América Latina

    Directory of Open Access Journals (Sweden)

    Junguito Bonnet Roberto

    1996-06-01

    Full Text Available This article describes the origin and evolution of the central banks of Argentina, Brazil, Chile, Colombia, Mexico, and Venezuela, and analyzes their respective institutional structures. It also studies the contribution of the central bank to stabilization and the problems for maintaining this independence into the future.Este artículo describe el origen y la evolución de los Bancos Centrales de Argentina, Brasil, Chile, Colombia, México y Venezuela, y analiza sus respectivas estructruras institucionales. También estudia la contribución de la banca central a la estabilización y los problemas para que esta independencia se mantenga en el futuro.

  4. Accelerated Evolution and Functional Divergence of the Dim Light Visual Pigment Accompanies Cichlid Colonization of Central America.

    Science.gov (United States)

    Hauser, Frances E; Ilves, Katriina L; Schott, Ryan K; Castiglione, Gianni M; López-Fernández, Hernán; Chang, Belinda S W

    2017-10-01

    Cichlids encompass one of the most diverse groups of fishes in South and Central America, and show extensive variation in life history, morphology, and colouration. While studies of visual system evolution in cichlids have focussed largely on the African rift lake species flocks, Neotropical cichlids offer a unique opportunity to investigate visual system evolution at broader temporal and geographic scales. South American cichlid colonization of Central America has likely promoted accelerated rates of morphological evolution in Central American lineages as they encountered reduced competition, renewed ecological opportunity, and novel aquatic habitats. To investigate whether such transitions have influenced molecular evolution of vision in Central American cichlids, we sequenced the dim-light rhodopsin gene in 101 Neotropical cichlid species, spanning the diversity of the clade. We find strong evidence for increased rates of evolution in Central American cichlid rhodopsin relative to South American lineages, and identify several sites under positive selection in rhodopsin that likely contribute to adaptation to different photic environments. We expressed a Neotropical cichlid rhodopsin protein invitro for the first time, and found that while its spectral tuning properties were characteristic of typical vertebrate rhodopsin pigments, the rate of decay of its active signalling form was much slower, consistent with dim light adaptation in other vertebrate rhodopsins. Using site-directed mutagenesis combined with spectroscopic assays, we found that a key amino acid substitution present in some Central American cichlids accelerates the rate of decay of active rhodopsin, which may mediate adaptation to clear water habitats. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Medicinal plants used in the traditional management of diabetes and its sequelae in Central America: A review.

    Science.gov (United States)

    Giovannini, Peter; Howes, Melanie-Jayne R; Edwards, Sarah E

    2016-05-26

    Globally 387 million people currently have diabetes and it is projected that this condition will be the 7th leading cause of death worldwide by 2030. As of 2012, its total prevalence in Central America (8.5%) was greater than the prevalence in most Latin American countries and the population of this region widely use herbal medicine. The aim of this study is to review the medicinal plants used to treat diabetes and its sequelae in seven Central American countries: Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama. We conducted a literature review and extracted from primary sources the plant use reports in traditional remedies that matched one of the following disease categories: diabetes mellitus, kidney disease, urinary problems, skin diseases and infections, cardiovascular disease, sexual dysfunctions, visual loss, and nerve damage. Use reports were entered in a database and data were analysed in terms of the highest number of use reports for diabetes management and for the different sequelae. We also examined the scientific evidence that might support the local uses of the most reported species. Out of 535 identified species used to manage diabetes and its sequelae, 104 species are used to manage diabetes and we found in vitro and in vivo preclinical experimental evidence of hypoglycaemic effect for 16 of the 20 species reported by at least two sources. However, only seven of these species are reported in more than 3 studies: Momordica charantia L., Neurolaena lobata (L.) R. Br. ex Cass., Tecoma stans (L.) Juss. ex Kunth, Persea americana Mill., Psidium guajava L., Anacardium occidentale L. and Hamelia patens Jacq. Several of the species that are used to manage diabetes in Central America are also used to treat conditions that may arise as its consequence such as kidney disease, urinary problems and skin conditions. This review provides an overview of the medicinal plants used to manage diabetes and its sequelae in Central America and of

  6. Disruption of the PV-PPV Phase Transition by a Dome-like Upwelling Beneath Alaska

    Science.gov (United States)

    Sun, D.; Helmberger, D. V.; Miller, M. S.

    2014-12-01

    The lowermost mantle region, D", represents one of the most dramatic thermal andcompositional layers within our planet. Global tomographic models display relatively fast patchsalong the circum-Pacific which is generally attributed to slab-debris. Such cold patches interactwith the PV-PPV phase boundary to generate particularly strong heterogeneity at their edges.Most seismic observations for the D" come from the lower mantle S wave triplication (Scd).However, the sampling regions concentrated beneath Central America, where intensive studies,including migration methods and array analysis, have been accomplished. Beneath the centralAmerica, the D" can have a step variation of ~ 100 km, which argues strong lateral temperaturevariations or possible chemical variations. However, the common used ray paths between SouthAmerican events and seismic stations in US sample such sharp boundary azimuthally, whichmake the modeling difficult. Here, we exploit the USArray waveform data to examine one ofthese sharp transitions beneath Alaska. From west to east beneath Alaska, we observed threedifferent type of D": West region with strong Scd requiring sharp δVS = 2% increase;Middle region with no clear Scd indicating lack of D"; East region with strong Scd requiring gradientδVS increase. To explain such strong lateral variation, chemical variations must be involved. Wesuggested that West region represents a normal mantle. In contrast, the east region is dominated bysubducted slab. At the Middle region, we discovered a strong upwelling structure that disrupts the phaseboundary. A distinct pattern of travel time delays, waveform distortions, and amplitude patternsreveal a circular anomaly about 5° across which can be modeled synthetically as a dome about400 km high with a shear velocity reduction of ~5%. Geodynamic modeling indicates thatthis structure could be the base of an upwelling and/or a hot Fe-rich oxide hill.

  7. Azimuthal anisotropy in the D″ layer beneath the Caribbean

    Science.gov (United States)

    Maupin, ValéRie; Garnero, Edward J.; Lay, Thorne; Fouch, Matthew J.

    2005-08-01

    The lowermost mantle beneath Central America has anisotropic seismic velocity structure manifested in shear wave splitting of signals from South American earthquakes recorded at North American broadband recording stations. Prior studies of deep mantle anisotropy in this region have characterized the structure as having vertical transverse isotropy (VTI), which is sufficient to explain a general trend of early tangential (SH) component arrivals. However, VTI models cannot quantitatively match systematic waveform complexities in the onset of many of the shear waves that graze this region. After accounting for splitting effects of upper mantle anisotropy beneath the recording stations, we model the corrected waveform data using full wave theory for mantle velocity models with an anisotropic D″ layer. This is the first attempt to quantitatively model a large data set including azimuthal anisotropy in D″. The models include transverse isotropy with either a vertical or tilted symmetry axis, the latter resulting in azimuthal anisotropy. For some initial shear wave polarizations, tilted transverse isotropy (TTI) produces small, reversed polarity arrivals on the SV components at the arrival time of SH, consistent with the data. Geographical variations in the azimuth of the TTI symmetry axis are indicated by the data. The lack of azimuthal coverage prevents unique resolution of the TTI orientation and also precludes distinguishing between TTI and other azimuthal anisotropy structures such as that predicted for lattice preferred orientation of minerals. Nonetheless, our modeling demonstrates the need for laterally varying anisotropic structure of more complex form than VTI for this region.

  8. Chronic kidney disease of nontraditional etiology in Central America: a provisional epidemiologic case definition for surveillance and epidemiologic studies.

    Science.gov (United States)

    Lozier, Matthew; Turcios-Ruiz, Reina Maria; Noonan, Gary; Ordunez, Pedro

    2016-11-01

    SYNOPSIS Over the last two decades, experts have reported a rising number of deaths caused by chronic kidney disease (CKD) along the Pacific coast of Central America, from southern Mexico to Costa Rica. However, this specific disease is not associated with traditional causes of CKD, such as aging, diabetes, or hypertension. Rather, this disease is a chronic interstitial nephritis termed chronic kidney disease of nontraditional etiology (CKDnT). According to the Pan American Health Organization (PAHO) mortality database, there are elevated rates of deaths related to kidney disease in many of these countries, with the highest rates being reported in El Salvador and Nicaragua. This condition has been identified in certain agricultural communities, predominantly among male farmworkers. Since CKD surveillance systems in Central America are under development or nonexistent, experts and governmental bodies have recommended creating standardized case definitions for surveillance purposes to monitor and characterize this epidemiological situation. A group of experts from Central American ministries of health, the U.S. Centers for Disease Control and Prevention (CDC), and PAHO held a workshop in Guatemala to discuss CKDnT epidemiologic case definitions. In this paper, we propose that CKD in general be identified by the standard definition internationally accepted and that a suspect case of CKDnT be defined as a person age diseases, and other well-known causes of CKD. A probable case of CKDnT is defined as a suspect case with the same findings confirmed three or more months later.

  9. Plants used in the traditional medicine of Mesoamerica (Mexico and Central America) and the Caribbean for the treatment of obesity.

    Science.gov (United States)

    Alonso-Castro, Angel Josabad; Domínguez, Fabiola; Zapata-Morales, Juan Ramón; Carranza-Álvarez, Candy

    2015-12-04

    Obesity is a worldwide medical concern. New ethnobotanical information regarding the antiobesity effect of medicinal plants has been obtained in the last 30 years in response to socio-demographic changes and high-fat diets became common. This review provides a summary of medicinal plants used in Mexico, Central America and the Caribbean for the empirical treatment of obesity in terms of ethnobotany, toxicity, pharmacology, conservation status, trade and chemistry. Bibliographic investigation was performed by analyzing recognized books, undergraduate and postgraduate theses and peer-reviewed scientific articles, consulting worldwide accepted scientific databases from the last four decades. Medicinal plants used for the treatment of obesity were classified in two categories: (1) plants with pharmacological evidence and (2) plants without pharmacological evidence. A total of 139 plant species, belonging to 61 families, native to Mexico, Central America and the Caribbean that are used for the empirical treatment of obesity were recorded. From these plants, 33 were investigated in scientific studies, and 106 plants lacked scientific investigation. Medicinal plants were experimentally studied in vitro (21 plants) and in vivo (16 plants). A total of 4 compounds isolated from medicinal plants used for the empirical treatment of obesity have been tested in vitro (2 compounds) and in vivo (4 compounds) studies. No clinical trials on obese subjects (BMI>30 kg/m(2)) have been performed using the medicinal plants cited in this review. There are no herbal-based products approved in Mexico for the treatment of obesity. There are a limited number of scientific studies published on medicinal plants from Mexico, Central America and the Caribbean used for the treatment of obesity. This review highlights the need to perform pharmacological, phytochemical, toxicological and ethnobotanical studies with medicinal flora to obtain new antiobesity agents. Copyright © 2015 Elsevier Ireland

  10. Recent viroid disease outbreaks in greenhouse tomatoes in North and Central America and their management

    Science.gov (United States)

    Greenhouse tomato productions in North America have suffered from several high profile viroid disease outbreaks in recent years. In this presentation, I will summarize and briefly describe each of these viroid disease outbreak and their relationship. What are viroids and their transmission through ...

  11. Two Species Previously Confused Under the Concept of Sabethes Tarsopus in Central America (Diptera: Culicidae)

    Science.gov (United States)

    1992-07-01

    Pan- 63, CH, 19 (CR 162) (flying in cacao planta - ama) made this study possible. One of us tion, 1100 h, hot, humid, cloudy). PANAMA. (JLP) gratefully...Middle America" 7. Costa Rica (CR). distribucion geografica y su importancia en Mosq. Syst. 9:237-287. salud publica. Tesis, licenciado en biologia

  12. Mid-term evaluation of the NRECA (National Rural Electric Cooperative Association) Central America Rural Electrification Support Program (CARES)

    Energy Technology Data Exchange (ETDEWEB)

    Perlack, R.D. (Oak Ridge National Lab., TN (USA)); Jones, H.G. (Oak Ridge Associated Universities, Inc., TN (USA)); Garcia, A. III (Texas A and M Univ., College Station, TX (USA). Dept. of Agricultural Engineering); Flores, E. (Flores (Edgar), Guatemala City (Guatemala))

    1990-09-01

    Oak Ridge National Laboratory was requested by the Regional Office for Central America and Panama to conduct a mid-term evaluation of the Cares Project, which is being implemented by the National Rural Electric Cooperative Association. This evaluation was conducted over a three week period by a four person team. Overall, the project has had numerous successes and is highly valued by local counterpart utilities and USAID Missions. Notwithstanding the significant results of the project, changes can be made in certain operating procedures and in the direction of some programmatic activities that can lead to an even more effective project.

  13. Primer registro de Ulmus ismaelis (Ulmaceae para Centroamérica First record of Ulmus ismaelis (Ulmaceae in Central America

    Directory of Open Access Journals (Sweden)

    José L. Linares

    2005-06-01

    Full Text Available Se registra por primera vez para Centroamérica Ulmus ismaelis Todzia et Panero (Ulmaceae, se proporciona una detallada redescripción de la especie tal como existe en la región y se comentan aspectos del hábitat y fenología.Ulmus ismaelis Todzia et Panero (Ulmaceae is recorded for the first time from Central America. A detailed redescription of the species, as it exists in the region, and aspects of its habitat and phenology are provided.

  14. Development and validation of a nutritional education pamphlet for low literacy pediatric oncology caregivers in Central America.

    Science.gov (United States)

    Garcia, Melissa; Chismark, Elisabeth A; Mosby, Terezie; Day, Sara W

    2010-12-01

    A culturally appropriate nutrition education pamphlet was developed and validated for low-literacy caregivers in Honduras, El Salvador, and Guatemala. The pamphlet was developed after a preliminary survey of pediatric oncology nurses in the 3 countries to assess the need for education materials, caregiver literacy levels, and local eating habits. Experts in nutrition and low-literacy patient education and pediatric oncology nurses validated the pamphlet's content and design. The pamphlet was validated positively and has been circulated to pediatric oncology caregivers in Central America.

  15. Development and Validation of a Nutritional Education Pamphlet for Low-Literacy Pediatric Oncology Caregivers in Central America

    Science.gov (United States)

    Garcia, Melissa; Chismark, Elisabeth A.; Mosby, Terezie; Day, Sara

    2013-01-01

    Background A culturally appropriate nutrition education pamphlet was developed and validated for low-literacy caregivers in Honduras, El Salvador, and Guatemala. Methods The pamphlet was developed after a preliminary survey of pediatric oncology nurses in the 3 countries to assess the need for education materials, caregiver literacy levels, and local eating habits. Experts in nutrition and low-literacy patient education and nurses validated the pamphlet’s content and design. Results and Conclusions Nurses expressed the need for nutrition-related pamphlets in developing countries. The pamphlet was validated positively by experts and nurses and has been circulated to pediatric oncology caregivers in Central America. PMID:20300913

  16. New evidence about the subduction of the Copiapó ridge beneath South America, and its connection with the Chilean-Pampean flat slab, tracked by satellite GOCE and EGM2008 models

    Science.gov (United States)

    Álvarez, Orlando; Gimenez, Mario; Folguera, Andres; Spagnotto, Silvana; Bustos, Emilce; Baez, Walter; Braitenberg, Carla

    2015-11-01

    Satellite-only gravity measurements and those integrated with terrestrial observations provide global gravity field models of unprecedented precision and spatial resolution, allowing the analysis of the lithospheric structure. We used the model EGM2008 (Earth Gravitational Model) to calculate the gravity anomaly and the vertical gravity gradient in the South Central Andes region, correcting these quantities by the topographic effect. Both quantities show a spatial relationship between the projected subduction of the Copiapó aseismic ridge (located at about 27°-30° S), its potential deformational effects in the overriding plate, and the Ojos del Salado-San Buenaventura volcanic lineament. This volcanic lineament constitutes a projection of the volcanic arc toward the retroarc zone, whose origin and development were not clearly understood. The analysis of the gravity anomalies, at the extrapolated zone of the Copiapó ridge beneath the continent, shows a change in the general NNE-trend of the Andean structures to an ENE-direction coincident with the area of the Ojos del Salado-San Buenaventura volcanic lineament. This anomalous pattern over the upper plate is interpreted to be linked with the subduction of the Copiapó ridge. We explore the relation between deformational effects and volcanism at the northern Chilean-Pampean flat slab and the collision of the Copiapó ridge, on the basis of the Moho geometry and elastic thicknesses calculated from the new satellite GOCE data. Neotectonic deformations interpreted in previous works associated with volcanic eruptions along the Ojos del Salado-San Buenaventura volcanic lineament is interpreted as caused by crustal doming, imprinted by the subduction of the Copiapó ridge, evidenced by crustal thickening at the sites of ridge inception along the trench. Finally, we propose that the Copiapó ridge could have controlled the northern edge of the Chilean-Pampean flat slab, due to higher buoyancy, similarly to the control

  17. Medicinal Plants from North and Central America and the Caribbean Considered Toxic for Humans: The Other Side of the Coin.

    Science.gov (United States)

    Alonso-Castro, Angel Josabad; Domínguez, Fabiola; Ruiz-Padilla, Alan Joel; Campos-Xolalpa, Nimsi; Zapata-Morales, Juan Ramón; Carranza-Alvarez, Candy; Maldonado-Miranda, Juan Jose

    2017-01-01

    The consumption of medicinal plants has notably increased over the past two decades. People consider herbal products as safe because of their natural origin, without taking into consideration whether these plants contain a toxic principle. This represents a serious health problem. A bibliographic search was carried out using published scientific material on native plants from Mexico, Central America, and the Caribbean, which describe the ethnobotanical and toxicological information of medicinal plants empirically considered to be toxic. A total of 216 medicinal plants belonging to 77 families have been reported as toxic. Of these plants, 76 had been studied, and 140 plants lacked studies regarding their toxicological effects. The toxicity of 16 plants species has been reported in clinical cases, particularly in children. From these plants, deaths have been reported with the consumption of Chenopodium ambrosioides , Argemone mexicana , and Thevetia peruviana . In most of the cases, the principle of the plant responsible for the toxicity is unknown. There is limited information about the toxicity of medicinal plants used in Mexico, Central America, and the Caribbean. More toxicological studies are necessary to contribute information about the safe use of the medicinal plants cited in this review.

  18. Medicinal Plants from North and Central America and the Caribbean Considered Toxic for Humans: The Other Side of the Coin

    Directory of Open Access Journals (Sweden)

    Angel Josabad Alonso-Castro

    2017-01-01

    Full Text Available The consumption of medicinal plants has notably increased over the past two decades. People consider herbal products as safe because of their natural origin, without taking into consideration whether these plants contain a toxic principle. This represents a serious health problem. A bibliographic search was carried out using published scientific material on native plants from Mexico, Central America, and the Caribbean, which describe the ethnobotanical and toxicological information of medicinal plants empirically considered to be toxic. A total of 216 medicinal plants belonging to 77 families have been reported as toxic. Of these plants, 76 had been studied, and 140 plants lacked studies regarding their toxicological effects. The toxicity of 16 plants species has been reported in clinical cases, particularly in children. From these plants, deaths have been reported with the consumption of Chenopodium ambrosioides, Argemone mexicana, and Thevetia peruviana. In most of the cases, the principle of the plant responsible for the toxicity is unknown. There is limited information about the toxicity of medicinal plants used in Mexico, Central America, and the Caribbean. More toxicological studies are necessary to contribute information about the safe use of the medicinal plants cited in this review.

  19. The complex biogeography of the plant pathogen Xylella fastidiosa: genetic evidence of introductions and Subspecific introgression in Central America.

    Directory of Open Access Journals (Sweden)

    Leonard Nunney

    Full Text Available The bacterium Xylella fastidiosa is a plant pathogen with a history of economically damaging introductions of subspecies to regions where its other subspecies are native. Genetic evidence is presented demonstrating the introduction of two new taxa into Central America and their introgression into the native subspecies, X. fastidiosa subsp. fastidiosa. The data are from 10 genetic outliers detected by multilocus sequence typing (MLST of isolates from Costa Rica. Six (five from oleander, one from coffee defined a new sequence type (ST53 that carried alleles at six of the eight loci sequenced (five of the seven MLST loci diagnostic of the South American subspecies Xylella fastidiosa subsp. pauca which causes two economically damaging plant diseases, citrus variegated chlorosis and coffee leaf scorch. The two remaining loci of ST53 carried alleles from what appears to be a new South American form of X. fastidiosa. Four isolates, classified as X. fastidiosa subsp. fastidiosa, showed a low level of introgression of non-native DNA. One grapevine isolate showed introgression of an allele from X. fastidiosa subsp. pauca while the other three (from citrus and coffee showed introgression of an allele with similar ancestry to the alleles of unknown origin in ST53. The presence of X. fastidiosa subsp. pauca in Central America is troubling given its disease potential, and establishes another route for the introduction of this economically damaging subspecies into the US or elsewhere, a threat potentially compounded by the presence of a previously unknown form of X. fastidiosa.

  20. Information to Act: Household Characteristics are Predictors of Domestic Infestation with the Chagas Vector Triatoma dimidiata in Central America

    Science.gov (United States)

    Zamora, Dulce María Bustamante; Hernández, Marianela Menes; Torres, Nuria; Zúniga, Concepción; Sosa, Wilfredo; de Abrego, Vianney; Escobar, María Carlota Monroy

    2015-01-01

    The interruption of vectorial transmission of Chagas disease by Triatoma dimidiata in central America is a public health challenge that cannot be resolved by insecticide application alone. In this study, we collected information on previously known household risk factors for infestation in 11 villages and more than 2,000 houses in Guatemala, Honduras, and El Salvador, and we constructed multivariate models and used multimodel inference to evaluate their importance as predictors of infestation in the region. The models had moderate ability to predict infested houses (sensitivity, 0.32–0.54) and excellent ability to predict noninfested houses (specificity higher than 0.90). Predictive ability was improved by including random village effects and presence of signs of infestation (insect feces, eggs, and exuviae) as fixed effects. Multimodel inference results varied depending on factors included, but house wall materials (adobe, bajareque, and palopique) and signs of infestation were among the most important predictive factors. Reduced models were not supported suggesting that all factors contributed to predictions. Previous knowledge and information from this study show that we have evidence to prioritize rural households for improvement to prevent house infestation with Triatoma dimidiata in Central America. House improvement will most likely have other health co-benefits. PMID:25870430

  1. Information to act: household characteristics are predictors of domestic infestation with the Chagas vector Triatoma dimidiata in Central America.

    Science.gov (United States)

    Bustamante Zamora, Dulce María; Hernández, Marianela Menes; Torres, Nuria; Zúniga, Concepción; Sosa, Wilfredo; de Abrego, Vianney; Monroy Escobar, María Carlota

    2015-07-01

    The interruption of vectorial transmission of Chagas disease by Triatoma dimidiata in central America is a public health challenge that cannot be resolved by insecticide application alone. In this study, we collected information on previously known household risk factors for infestation in 11 villages and more than 2,000 houses in Guatemala, Honduras, and El Salvador, and we constructed multivariate models and used multimodel inference to evaluate their importance as predictors of infestation in the region. The models had moderate ability to predict infested houses (sensitivity, 0.32-0.54) and excellent ability to predict noninfested houses (specificity higher than 0.90). Predictive ability was improved by including random village effects and presence of signs of infestation (insect feces, eggs, and exuviae) as fixed effects. Multimodel inference results varied depending on factors included, but house wall materials (adobe, bajareque, and palopique) and signs of infestation were among the most important predictive factors. Reduced models were not supported suggesting that all factors contributed to predictions. Previous knowledge and information from this study show that we have evidence to prioritize rural households for improvement to prevent house infestation with Triatoma dimidiata in Central America. House improvement will most likely have other health co-benefits. © The American Society of Tropical Medicine and Hygiene.

  2. The complex biogeography of the plant pathogen Xylella fastidiosa: genetic evidence of introductions and Subspecific introgression in Central America.

    Science.gov (United States)

    Nunney, Leonard; Ortiz, Beatriz; Russell, Stephanie A; Ruiz Sánchez, Rebeca; Stouthamer, Richard

    2014-01-01

    The bacterium Xylella fastidiosa is a plant pathogen with a history of economically damaging introductions of subspecies to regions where its other subspecies are native. Genetic evidence is presented demonstrating the introduction of two new taxa into Central America and their introgression into the native subspecies, X. fastidiosa subsp. fastidiosa. The data are from 10 genetic outliers detected by multilocus sequence typing (MLST) of isolates from Costa Rica. Six (five from oleander, one from coffee) defined a new sequence type (ST53) that carried alleles at six of the eight loci sequenced (five of the seven MLST loci) diagnostic of the South American subspecies Xylella fastidiosa subsp. pauca which causes two economically damaging plant diseases, citrus variegated chlorosis and coffee leaf scorch. The two remaining loci of ST53 carried alleles from what appears to be a new South American form of X. fastidiosa. Four isolates, classified as X. fastidiosa subsp. fastidiosa, showed a low level of introgression of non-native DNA. One grapevine isolate showed introgression of an allele from X. fastidiosa subsp. pauca while the other three (from citrus and coffee) showed introgression of an allele with similar ancestry to the alleles of unknown origin in ST53. The presence of X. fastidiosa subsp. pauca in Central America is troubling given its disease potential, and establishes another route for the introduction of this economically damaging subspecies into the US or elsewhere, a threat potentially compounded by the presence of a previously unknown form of X. fastidiosa.

  3. Methodological and Practical Considerations for DevelopingMultiproject Baselines for Electric Power and Cement Industry Projects inCentral America

    Energy Technology Data Exchange (ETDEWEB)

    Murtishaw, Scott; Sathaye, Jayant; Galitsky, Christina; Dorion,Kristel

    2004-09-02

    The Lawrence Berkeley National Laboratory (Berkeley Lab) andthe Center for Sustainable Development in the Americas (CSDA) conductedtechnical studies and organized two training workshops to developcapacity in Central America for the evaluation of climate changeprojects. This paper describes the results of two baseline case studiesconducted for these workshops, one for the power sector and one for thecement industry, that were devised to illustrate certain approaches tobaseline setting. Multiproject baseline emission rates (BERs) for themain Guatemalan electricity grid were calculated from 2001 data. Inrecent years, the Guatemalan power sector has experienced rapid growth;thus, a sufficient number of new plants have been built to estimateviable BERs. We found that BERs for baseload plants offsetting additionalbaseload capacity ranged from 0.702 kgCO2/kWh (using a weighted averagestringency) to 0.507 kgCO2/kWh (using a 10th percentile stringency),while the baseline for plants offsetting load-followingcapacity is lowerat 0.567 kgCO2/kWh. For power displaced from existing load-followingplants, the rate is higher, 0.735 kgCO2/kWh, as a result of the age ofsome plants used for meeting peak loads and the infrequency of their use.The approved consolidated methodology for the Clean Development Mechanismyields a single rate of 0.753 kgCO2/kWh. Due to the relatively smallnumber of cement plants in the region and the regional nature of thecement market, all of Central America was chosen as the geographicboundary for setting cement industry BERs. Unfortunately, actualoperations and output data were unobtainable for most of the plants inthe region, and many data were estimated. Cement industry BERs rangedfrom 205 kgCO2 to 225 kgCO2 per metric ton of cement.

  4. Effect of a huge crustal conductivity anomaly on the H-component of geomagnetic variations recorded in central South America

    Science.gov (United States)

    Padilha, Antonio L.; Alves, Livia R.; Silva, Graziela B. D.; Espinosa, Karen V.

    2017-04-01

    We describe here an analysis of the H-component of the geomagnetic field recorded in several temporary stations operating simultaneously in the central-eastern region of Brazil during nighttime pulsation events in 1994 and the sudden commencement of the St. Patrick's Day magnetic storm in 2015. A significant amplification in the amplitude of the geomagnetic variations is consistently observed in one of these stations. Magnetovariational analysis indicates that the amplification factor is period dependent with maximum amplitude around 100 s. Integrated magnetotelluric (MT) and geomagnetic depth soundings (GDS) have shown that this station is positioned just over a huge 1200-km-long crustal conductor (estimated bulk conductivity greater than 1 S/m). We propose that the anomalous signature of the geomagnetic field at this station is due to the high reflection coefficient of the incident electromagnetic wave at the interface with the very good conductor and by skin effects damping the electromagnetic wave in the conducting layers overlying the conductor. There are some indication from the GDS data that the conductor extends southward beneath the sediments of the Pantanal Basin. In this region is being planned the installation of a new geomagnetic observatory, but its preliminary data suggest anomalous geomagnetic variations. We understand that a detailed MT survey must be carried out around the chosen observatory site to evaluate the possible influence of induced currents on the local geomagnetic field.[Figure not available: see fulltext.

  5. The mobility of students in Central America: in search of hegemonic knowledge?

    Directory of Open Access Journals (Sweden)

    Edorta CAMINO ESTURO

    2018-01-01

    Full Text Available The dynamics of Central American students’ mobility is characterized by one-way mobility to the Western countries, as centers of hegemonic knowledge, especially the United States. However, there has been an increase in academic mobility to Cuba, which suggests the emergence of an alternative space and a counterbalance to this trend. Instead, mobility towards the Central American region is domestic and peripheral, with more intraregional than foreign contributions, standing on the sidelines of university centers of scientific production.

  6. The Previously Undetected Presence of Culex restuans (Diptera: Culicidae) in Central America, with Notes on Identification

    Science.gov (United States)

    1988-01-01

    Culicidae). Proc. U.S. Nat. Mus. 120 (3557): 122 pp. Carpenter , S.J. and W.J. LaCasse . 1955. Mosquitoes of North America (north of Mexico). Univ...specimens HONC- 30G, GUA 118-l 1, and GUA 118-27 were similar to the distinctive form of this structure described by Carpenter and La Casse (1955) and...specimens from Virginia examined by Bram. Larvae and adults closely resembled descriptions by Carpenter and La Casse (1955) and by Bohart and Washino (1978

  7. Pleistocene to holocene expansion of the black-belt cichlid in Central America, Vieja maculicauda (Teleostei: Cichlidae.

    Directory of Open Access Journals (Sweden)

    Caleb D McMahan

    Full Text Available The distributions of many Northern Hemisphere organisms have been influenced by fluctuations in sea level and climatic conditions during Pleistocene interglacial periods. These cycles are associated with range contraction and refugia for northern-distributed organisms as a response to glaciers. However, lower sea levels in the tropics and sub-tropics created available habitat for expansion of the ranges of freshwater organisms. The goal of this study was to use ecological niche modeling to test the hypothesis of north to south range expansion of Vieja maculicauda associated with Pleistocene glacial cycles. Understanding the biogeography of this widespread species may help us better understand the geology and interconnectivity of Central American freshwaters. Occurrence data for V. maculicauda was based on georeferencing of all museum records of specimens recovered from FishNet2. General patterns of phylogeographic structure were assessed with mtDNA. Present day niche models were generated and subsequently projected onto paleoclimatic maps of the region during the Last Interglacial, Last Glacial Maximum, and mid-Holocene. Phylogenetic analysis of mtDNA sequence data showed no phylogeographic structure throughout the range of this widespread species. Present day niche models were congruent with the observed distribution of V. maculicauda in Central America. Results showed a lack of suitable freshwater habitat in northern Central America and Mexico during the Last Interglacial, with greatest range expansion during the Last Glacial Maximum and mid-Holocene. Results support the hypothesis of a north to south range expansion of V. maculicauda associated with glacial cycles. The wide distribution of this species compared to other closely related cichlids indicates the latter did not respond to the degree of V. maculicauda in expansion of their distributions. Future work aimed at comparisons with other species and modeling of future climatic scenarios

  8. Chronic kidney disease of nontraditional etiology in Central America: a provisional epidemiologic case definition for surveillance and epidemiologic studies

    Directory of Open Access Journals (Sweden)

    Matthew Lozier

    Full Text Available SYNOPSIS Over the last two decades, experts have reported a rising number of deaths caused by chronic kidney disease (CKD along the Pacific coast of Central America, from southern Mexico to Costa Rica. However, this specific disease is not associated with traditional causes of CKD, such as aging, diabetes, or hypertension. Rather, this disease is a chronic interstitial nephritis termed chronic kidney disease of nontraditional etiology (CKDnT. According to the Pan American Health Organization (PAHO mortality database, there are elevated rates of deaths related to kidney disease in many of these countries, with the highest rates being reported in El Salvador and Nicaragua. This condition has been identified in certain agricultural communities, predominantly among male farmworkers. Since CKD surveillance systems in Central America are under development or nonexistent, experts and governmental bodies have recommended creating standardized case definitions for surveillance purposes to monitor and characterize this epidemiological situation. A group of experts from Central American ministries of health, the U.S. Centers for Disease Control and Prevention (CDC, and PAHO held a workshop in Guatemala to discuss CKDnT epidemiologic case definitions. In this paper, we propose that CKD in general be identified by the standard definition internationally accepted and that a suspect case of CKDnT be defined as a person age < 60 years with CKD, without type 1 diabetes mellitus, hypertensive diseases, and other well-known causes of CKD. A probable case of CKDnT is defined as a suspect case with the same findings confirmed three or more months later.

  9. A new species of the genus Mahanarva Distant, 1909 (Hemiptera: Cercopoidea: Cercopidae, with a key to the species from Central America and Mexico

    Directory of Open Access Journals (Sweden)

    Ulises Castro–Valderrama

    2018-02-01

    Full Text Available The genus Mahanarva Distant, 1909 (Hemiptera: Cercopoidea: Cercopidae currently includes two subgenera: Mahanarva Distant, 1909 with 38 species and six subspecies, and Ipiranga Fennah, 1968 with nine species. The Manaharva species are all from the Americas, and a few species are important pests in pasture grasses and sugarcane. There are no reports of any Manaharva species from North America, including Mexico and areas to the north. Here, a new species is described from Mexico and a key to the species of Mahanarva from Central America and Mexico is proposed.

  10. Complex seismic anisotropy beneath the IPOC stations of northern Chile

    Science.gov (United States)

    Reiss, Miriam Christina; Wölbern, Ingo; Rümpker, Georg

    2017-04-01

    The subduction of the Nazca plate beneath Central South America has been subject to numerous seismological studies. Here, we focus on seismic anisotropy which provides a direct link to the dynamic processes acting within the upper mantle and crust. The main mechanisms responsible for the development of large scale anisotropy are: i) crystallographic preferred orientation of upper mantle minerals and ii) shape-preferred orientation caused by cracks, melt-filled lenses or alternating layers within the crust. In this context, subduction zones represent a complex anisotropic puzzle as seismic anisotropy can be located in regions beneath, within, and above the subducting slab. We use the analysis of teleseismic shear-wave splitting to measure seismic anisotropy in response to subduction-related deformation processes. Previous studies on shear-wave splitting from South America have reported partly contradicting results and interpretations in terms of mantle flow and crustal deformation. Russo and Silver (1994) mostly found trench-parallel fast polarizations which they attributed to trench-parallel mantle flow beneath the slab and confined zones of oblique polarization directions. Wölbern et al. (2014) reported significant short-scale variations of fast polarization directions. They proposed that anisotropy results from fossil anisotropy in the subducting slab, whereas deviating fast polarizations in trench-parallel orientation were attributed to crustal anisotropy related to deep-reaching local shear zones. Long et al. (2016) found complex splitting measurements which they interpreted as the result of different anisotropic source regions. Overall, the complexity of splitting measurements yield a departure from a conventional 2D corner flow model. To investigate the upper mantle and crust in this subduction setting further, we use data from the Integrated Plate boundary Observatory Chile (IPOC) located in northern Chile, which consists of 21 stations with up to ten years

  11. The Central American Crisis and the Construction of a New International Order in Latin America

    Directory of Open Access Journals (Sweden)

    Manuel Montobbio

    1997-09-01

    Full Text Available The author claims that the 1980s saw the emergence of Latin America as a subject within the international system. The first signs of this new dynamic were seen in the Latin American solidarity during the War of the Malvinas and in these countries’ coordinated efforts before the debt crisis and its negotiations. The definitive push came about as a result of the attempts to create a regional solution, thus paving the way for a qualitative leap forward to take place in the foreign policies of Latin American countries. By the 1990s, this tendency would lead towards the creation of a regional security system based on cooperation and shared sovereignties, secured frameworks of regional economic integration, and the consolidation of the processes of political transition.

  12. Two Triatoma dimidiata clades (Chagas disease vector) associated with different habitats in southern Mexico and Central America.

    Science.gov (United States)

    Tamay-Segovia, Paulino; Alejandre-Aguilar, Ricardo; Martínez, Fernando; Villalobos, Guiehdani; de la Serna, Francisco J Zavala-Díaz; de la Torre, Patricia; Laclette, Juan Pedro; Blum-Domínguez, Selene; Espinoza, Bertha

    2008-03-01

    Triatoma dimidiata is the only reported Chagas disease vector in Campeche, Mexico. The purpose of this study was to determine the genetic variability of vectors from Campeche coastal and rain forest areas and establish a phylogenetic relationship with other T. dimidiata populations by analyzing the internal transcribed spacer-2 (ITS-2) region. The sequence length of samples from Campeche ranged from 469 to 478 basepairs. The ITS-2 variability among the populations enabled us to classify them into two clades with an 18-22 nucleotide difference. The genetic distance (0.042) between them confirms this divergence. Phylogenetic analysis of gene genealogies confirmed these two clades. Furthermore, the population genetic analyses showed two groups with little genetic similarity or migration between them. One group was associated with the tropical forest area and the other group was associated with a mainly coastal distribution. This correlation was also observed when T. dimidiata from other regions of Mexico and Central America were analyzed.

  13. [The inclusion of human rights in AIDS/HIV norms in Mexico and Central America: 1993-2000].

    Science.gov (United States)

    Cuadra-Hernández, Silvia Magali; Leyva-Flores, René; Hernández-Rosete, Daniel; Bronfman-Pertzovsky, Mario N

    2002-01-01

    To analyze the inclusion of human rights in HIV/AIDS norms in Mexico and Central America for the 1993-2000 period. Norms and regulations for HIV/AIDS prevention and control in this region were analyzed. A constructivist perspective of judiciary subsystems and human rights was used as a reference framework, to establish categories of analysis with significance codes based on the Universal Declaration of Human Rights. During the study period, human rights were included within a vigorous legislative activity for HIV/AIDS transmission prevention. In some cases (as in the Panama Law and the Honduras Proposal) there were passages of law violating the right to non-discrimination and privacy. These laws lead to either of two conflicting paths: one ensuring human rights, and another increasing the vulnerability of some groups. The authors emphasize the importance of gaining a new understanding of social subjects and epidemiological surveillance, based on norms that incorporate human rights issues.

  14. Climatic change on the Gulf of Fonseca (Central America) using two-step statistical downscaling of CMIP5 model outputs

    Science.gov (United States)

    Ribalaygua, Jaime; Gaitán, Emma; Pórtoles, Javier; Monjo, Robert

    2018-05-01

    A two-step statistical downscaling method has been reviewed and adapted to simulate twenty-first-century climate projections for the Gulf of Fonseca (Central America, Pacific Coast) using Coupled Model Intercomparison Project (CMIP5) climate models. The downscaling methodology is adjusted after looking for good predictor fields for this area (where the geostrophic approximation fails and the real wind fields are the most applicable). The method's performance for daily precipitation and maximum and minimum temperature is analysed and revealed suitable results for all variables. For instance, the method is able to simulate the characteristic cycle of the wet season for this area, which includes a mid-summer drought between two peaks. Future projections show a gradual temperature increase throughout the twenty-first century and a change in the features of the wet season (the first peak and mid-summer rainfall being reduced relative to the second peak, earlier onset of the wet season and a broader second peak).

  15. Migration patterns in Central America seen in the context of economic integration and the need for sustainable development.

    Science.gov (United States)

    Stein, E

    1993-08-01

    This exploratory discussion of migration policy in Central America focuses on actual procedures in a multisectoral framework that assumes economic integration and sustainable development. The article follows the following format: the author's perspective and general approach to the problems of migration policy and integrated development, an analysis and review of the inadequacies of concepts and methodologies and the need for strengthening Central America's policies, arguments for changing present development strategies, and suggestions for regional economic integration. New policies must be equitable, sustainable, and suitable for agricultural frontier areas at the present level of economic integration. The further development of practical and concrete solutions in the region is based on the current groundwork. New policies should emphasize community participation, a grassroots approach rather than a top-down one, and an alternative model. An alternative system which promotes and facilitates the vertical development of small and medium farmers needs both a Rural Communal Financing System and a System for Communal Marketing to eliminate all speculative economic practices which impede small farmers from making a profit. Buffer zones in the frontier agricultural areas are required. Small farms need to gradually improve farming practices rather than to transfer miraculous technologies. A number of forest products could be collected and commercialized for various purposes, if the knowledgeable indigenous population is informed and involved in participatory research on the technical and ethnological culture and action programs. Many sectors are involved, problems are complex, and the speed of change is very rapid in the region. An approach that seeks to relate sustainable development, economic integration, and migration policy must incorporate the perspective of integrated development and a structural analysis of poverty. The approach suggested in this article would

  16. Structural Vulnerability Among Migrating Women and Children Fleeing Central America and Mexico: The Public Health Impact of "Humanitarian Parole".

    Science.gov (United States)

    Valdez, Elizabeth Salerno; Valdez, Luis A; Sabo, Samantha

    2015-01-01

    Since October 2013, US Customs and Border Patrol has apprehended 15,979 families on the Southwest Border of the US. Daily, migrating women and children from Mexico and Central America that qualify for humanitarian parole are released from immigration detention to a humanitarian aid organization in Southern Arizona. After several days in detention facilities, these families arrive tired, hungry, dehydrated, and with minimal direction regarding their final destination, and adherence to the parameters of their parole. Project helping hands (PHHs) utilizes a network of volunteers to provide the women and children with food, water, clothing, hygiene products, hospitality, and legal orientation. The aim of this assessment was to document the experiences of families granted humanitarian parole through the lens of structural vulnerability. Here, we apply qualitative methods to elicit PHH lead volunteer perspectives regarding the migration experience of migrating families. Using inductive analysis, we found six major themes emerged from the qualitative data: reasons for leaving, experience on the journey, dehumanization in detention, family separation, vulnerability, and resiliency. These findings elucidate the different physical and psychological distresses that migrating families from Mexico and Central America experience before, during and after their arrival at the US-Mexico border. We posit that these distresses are a result of, or exacerbated by, structural vulnerability. Structural vulnerability has life-long health implications for a sub-population of young mothers and their children. The number of migrating families who have experienced traumatic events before and during their migration experience continues to expand and thus warrants consideration of mental health surveillance and intervention efforts for these families. More public health research is needed to better understand and combat the health challenges of this growing population.

  17. Structural Vulnerability among Migrating Women and Children Fleeing Central America and Mexico:The Public Health Impact of Humanitarian Parole

    Directory of Open Access Journals (Sweden)

    Elizabeth Salerno Valdez

    2015-06-01

    Full Text Available Since October 2013, US Customs and Border Patrol (USCBP has apprehended 15,979 families on the Southwest Border of the United States. Daily, migrating women and children from Mexico and Central America that qualify for humanitarian parole are released from immigration detention to a humanitarian aid organization in Southern Arizona. After several days in detention facilities, these families arrive tired, hungry, dehydrated, and with minimal direction regarding their final destination, and adherence to the parameters of their parole. Project Helping Hands (PHH utilizes a network of volunteers to provide the women and children with food, water, clothing, hygiene products, hospitality, and legal orientation. The aim of this assessment was to document the experiences of families granted humanitarian parole through the lens of structural vulnerability. Here we apply qualitative methods to elicit PHH lead volunteer perspectives regarding the migration experience of migrating families. Using inductive analysis, we found six major themes emerged from the qualitative data: reasons for leaving, experience on the journey, dehumanization in detention, family separation, vulnerability, and resiliency.These findings elucidate the different physical and psychological distresses that migrating families from Mexico and Central America experience before, during and after their arrival at the US-Mexico border. We posit that these distresses are a result of, or exacerbated by, structural vulnerability. Structural vulnerability has life-long health implications for a sub-population of young mothers and their children. The number of migrating families who have experienced traumatic events before, and during their migration experience continues to expand and thus warrants consideration of mental health surveillance and intervention efforts for these families. More public health research is needed to better understand and combat the health challenges of this growing

  18. Rainforest understory beetles of the Neotropics: Mizotrechus Bates 1872, a generic synopsis with descriptions of new species from Central America and northern South America (Coleoptera, Carabidae, Perigonini

    Directory of Open Access Journals (Sweden)

    Terry Erwin

    2011-11-01

    Full Text Available Information on the single previously described species, Mizotrechus novemstriatus Bates 1872 (type locality: Brazil – Amazonas, Tefé, is updated and 17 new species for the genus from Nicaragua, Costa Rica, Panamá, Colombia, Venezuela, and Guyane are described. The species records in the literature and on determined specimens in some collections of M. novemstriatus Bates from Central America are not that species; currently, M. novemstriatus is known only from its type locality in Amazonian Brazil. For the new species described, their known general distributions are as follows: Mizotrechus batesi sp. n. (Guyane, Mizotrechus bellorum sp. n. (Guyane, Mizotrechus brulei sp. n. (Guyane, Mizotrechus belevedere sp. n. (Guyane, Mizotrechus costaricensis sp. n. (Costa Rica, Mizotrechus dalensi sp. n. (Guyane, Mizotrechus edithpiafae sp. n. (provenance unknown, Mizotrechus fortunensis sp. n. (Panamá, Mizotrechus gorgona. sp. n. (Colombia, Mizotrechus grossus sp. n. (Guyane, Mizotrechus jefe sp. n. (Panamá, Mizotrechus marielaforetae sp. n. (Guyane, Mizotrechus minutus sp. n. (Guyane, Mizotrechus neblinensis sp. n. (Guyane, Venezuela, Mizotrechus poirieri sp. n. (Guyane, and Mizotrechus woldai sp. n. (Panamá. Long-term use of flight intercept traps in Guyane provided so many new species that apparently the use of FITs is the way to collect adults of this taxon, previously known from very few specimens. Many more species of this genus can be expected to be discovered throughout the Neotropics; the present contribution is a preliminary synopsis with identification key and adult images of all known species. Likely numerous species are yet to be discovered throughout tropical climes.

  19. Programmes, resources, and needs of HIV-prevention nongovernmental organizations (NGOs) in Africa, Central/Eastern Europe and Central Asia, Latin America and the Caribbean.

    Science.gov (United States)

    Kelly, J A; Somlai, A M; Benotsch, E G; Amirkhanian, Y A; Fernandez, M I; Stevenson, L Y; Sitzler, C A; McAuliffe, T L; Brown, K D; Opgenorth, K M

    2006-01-01

    This study assessed the programmes, resources, and needs of HIV-prevention nongovernmental organizations (NGOs) in 75 countries in Africa, Central/Eastern Europe and Central Asia, Latin America and the Caribbean. Multiple databases and expert recommendations were used to identify one major HIV-prevention NGO in the capital or a large city in each country, and in-depth interviews were conducted with each NGO Director. Most NGOs are carrying out their programmes with minimal funding and few regularly employed personnel. Most are highly dependent on international donors, but reliance on small grants with short funding periods limits programme development capacity. HIV-prevention activities varied by region, with African NGOs most likely to use peer education and community awareness events; Eastern European NGOs most likely to offer needle exchange; Latin American NGOs to have resource centres and offer risk reduction programmes; and Caribbean organizations to use mass education approaches. Across regions, NGOs most often targeted the general public and youth, although specialized at-risk groups were the additional focus of attention in some regions. Limited funding, governmental indifference or opposition, AIDS stigma, and social discomfort discussing sex were often cited as barriers to new HIV-prevention programmes. NGOs are critical service providers. However, their funding, programmes, and resource capacities must be strengthened if NGOs are to realize their full potential in HIV prevention.

  20. Changing drug markets under new intellectual property regimes: the view from Central America.

    Science.gov (United States)

    Godoy, Angelina Snodgrass; Cerón, Alejandro

    2011-07-01

    The intellectual property rules inscribed in the Central American Free Trade Agreement have generated concern about access to medicines. We examined the implementation of the new intellectual property regime by tracking the policies and practices in place across 4 Central American countries. Although all 4 were responding to the same requirements under the agreement, their implementation of intellectual property rules differed. Not only were institutional practices different, but the lists of drugs to which intellectual property protection was applied varied in both volume and content. We also found that even without the influence of intellectual property, drug pricing in the region was often unpredictable and that lower cost was not the only motivation driving governments' purchasing decisions.

  1. The greenhouse effect in central North America: If not now, when?

    International Nuclear Information System (INIS)

    Karl, T.R.; Heim, R.R. Jr.

    1991-01-01

    The consistency of the predictions of the Intergovernmental Panel on Climate Change (IPCC) with observed data are discussed, with reference to statistical models and Monte-Carlo simulation. Climate change projections for North America predict increases of temperature of 2-4 degree C by 2030. Analysis of the climate record over the last 95 years has failed to indicate statistically significant changes. Statistical models using auto-regressive moving-average techniques have been developed to calculate the likelihood that the greenhouse signal may have been masked by natural climate variability, and have indicated that there is a high probability that changes have been masked. However, some projections, such as the increase in ratio of winter to summer precipitation, should have been detected. The probability of not detecting temperature changes as large as projected range from 5% for large temperature increases to 65% for smaller increases, depending on the scenario. These results suggest that the projections of large increases in temperature of 3-4 degree C are inconsistent with past observation. It will likely take 15-20 years beyond 1990 before summer temperature increases would be detected, and over 40 years before summer precipitation decreases would be detected, assuming IPCC projections are basically correct. 13 refs., 3 figs., 4 tabs

  2. Differential effects of landscape-level environmental features on genetic structure in three codistributed tree species in Central America.

    Science.gov (United States)

    Poelchau, Monica F; Hamrick, J L

    2012-10-01

    Landscape genetic studies use spatially explicit population genetic information to determine the physical and environmental causes of population genetic structure on regional scales. Comparative studies that identify common barriers to gene flow across multiple species within a community are important to both understand the evolutionary trajectories of populations and prioritize habitat conservation. Here, we use a comparative landscape genetic approach to ask whether gradients in temperature or precipitation seasonality structure genetic variation across three codistributed tree species in Central America, or whether a simpler (geographic distance) or more complex, species-specific environmental niche model is necessary to individually explain population genetic structure. Using descriptive statistics and causal modelling, we find that different factors best explain genetic distance in each of the three species: environmental niche distance in Bursera simaruba, geographic distance in Ficus insipida and historical barriers to gene flow or cryptic reproductive barriers for Brosimum alicastrum. This study confirms suggestions from previous studies of Central American tree species that imply that population genetic structure of trees in this region is determined by complex interactions of both historical and current barriers to gene flow. © 2012 Blackwell Publishing Ltd.

  3. Late Quaternary moisture export across Central America and to Greenland: evidence for tropical rainfall variability from Costa Rican stalagmites

    Science.gov (United States)

    Lachniet, Matthew S.; Johnson, Leah; Asmerom, Yemane; Burns, Stephen J.; Polyak, Victor; Patterson, William P.; Burt, Lindsay; Azouz, April

    2009-12-01

    We present a high-resolution terrestrial archive of Central American rainfall over the period 100-24 and 8.1-6.5 ka, based on δ 18O time series from U-series dated stalagmites collected from a cave on the Pacific Coast of Costa Rica. Our results indicate substantial δ 18O variability on millennial to orbital time scales that is interpreted to reflect rainfall variations over the cave site. Correlations with other paleoclimate proxy records suggest that the rainfall variations are forced by sea surface temperatures (SST) in the Atlantic and Pacific Oceans in a fashion analogous to the modern climate cycle. Higher rainfall is associated with periods of a warm tropical North Atlantic Ocean and large SST gradients between the Atlantic and Pacific Oceans. Rainfall variability is likely linked to the intensity and/or latitudinal position of the intertropical convergence zone (ITCZ). Periods of higher rainfall in Costa Rica are also associated with an enhanced sea surface salinity gradient on either side of the isthmus, suggesting greater freshwater export from the Atlantic Basin when the ITCZ is stronger and/or in a more northerly position. Further, wet periods in Central America coincide with high deuterium excess values in Greenland ice, suggesting a direct link between low latitude SSTs, tropical rainfall, and moisture delivery to Greenland. Our results indicate that a stronger tropical hydrological cycle during warm periods and large inter-ocean SST gradients enhanced the delivery of low latitude moisture to Greenland.

  4. Hydro, wind and solar power as a base for a 100% renewable energy supply for South and Central America.

    Science.gov (United States)

    Barbosa, Larissa de Souza Noel Simas; Bogdanov, Dmitrii; Vainikka, Pasi; Breyer, Christian

    2017-01-01

    Power systems for South and Central America based on 100% renewable energy (RE) in the year 2030 were calculated for the first time using an hourly resolved energy model. The region was subdivided into 15 sub-regions. Four different scenarios were considered: three according to different high voltage direct current (HVDC) transmission grid development levels (region, country, area-wide) and one integrated scenario that considers water desalination and industrial gas demand supplied by synthetic natural gas via power-to-gas (PtG). RE is not only able to cover 1813 TWh of estimated electricity demand of the area in 2030 but also able to generate the electricity needed to fulfil 3.9 billion m3 of water desalination and 640 TWhLHV of synthetic natural gas demand. Existing hydro dams can be used as virtual batteries for solar and wind electricity storage, diminishing the role of storage technologies. The results for total levelized cost of electricity (LCOE) are decreased from 62 €/MWh for a highly decentralized to 56 €/MWh for a highly centralized grid scenario (currency value of the year 2015). For the integrated scenario, the levelized cost of gas (LCOG) and the levelized cost of water (LCOW) are 95 €/MWhLHV and 0.91 €/m3, respectively. A reduction of 8% in total cost and 5% in electricity generation was achieved when integrating desalination and power-to-gas into the system.

  5. Hydro, wind and solar power as a base for a 100% renewable energy supply for South and Central America

    Science.gov (United States)

    Barbosa, Larissa de Souza Noel Simas; Bogdanov, Dmitrii; Vainikka, Pasi; Breyer, Christian

    2017-01-01

    Power systems for South and Central America based on 100% renewable energy (RE) in the year 2030 were calculated for the first time using an hourly resolved energy model. The region was subdivided into 15 sub-regions. Four different scenarios were considered: three according to different high voltage direct current (HVDC) transmission grid development levels (region, country, area-wide) and one integrated scenario that considers water desalination and industrial gas demand supplied by synthetic natural gas via power-to-gas (PtG). RE is not only able to cover 1813 TWh of estimated electricity demand of the area in 2030 but also able to generate the electricity needed to fulfil 3.9 billion m3 of water desalination and 640 TWhLHV of synthetic natural gas demand. Existing hydro dams can be used as virtual batteries for solar and wind electricity storage, diminishing the role of storage technologies. The results for total levelized cost of electricity (LCOE) are decreased from 62 €/MWh for a highly decentralized to 56 €/MWh for a highly centralized grid scenario (currency value of the year 2015). For the integrated scenario, the levelized cost of gas (LCOG) and the levelized cost of water (LCOW) are 95 €/MWhLHV and 0.91 €/m3, respectively. A reduction of 8% in total cost and 5% in electricity generation was achieved when integrating desalination and power-to-gas into the system. PMID:28329023

  6. Dome-like low velocity upwelling in D" beneath Alaska imaged with USArray data

    Science.gov (United States)

    Sun, Daoyuan; Miller, Meghan S.; Helmberger, Don

    2015-04-01

    The lowermost mantle region, D", represents one of the most dramatic thermal and compositional layers within our planet. Global tomographic models display relatively fast patches along the circum-Pacific which are generally attributed to slab-related debris. Most seismic observations for the D" boundary layer come from the lower mantle S wave triplication (Scd). However, the most sampled regions are concentrated beneath Central America, where intensive studies, including migration methods and array analysis, have been accomplished. Beneath Central America, the D" can have a step variation of ~100 km, which argues strong lateral temperature variations or possible chemical variations. However, the commonly used ray paths between South American events and seismic stations in North America sample this sharp boundary azimuthally, which is difficult to model. Here, we exploit the USArray waveform data to examine a sharp transition beneath Alaska. From west to east beneath Alaska, we observe three different types of structures in the D" layer: in the western region we observed a strong Scd phase, which requires a sharp δVS = 2% increase; in the middle region there is no clear Scd phase indicating no D" layer; in the eastern region we observe a strong Scd phase requiring a positive gradient δVS. To explain such strong lateral differences in seismic velocity, we propose a chemical variation. We suggest that the western region represents a "normal" lowermost mantle. In contrast, the eastern region has fast velocities, which appears to influenced by the subducted Pacific slab. In the middle region, we interpret an upwelling structure that disrupts the phase boundary. This is based upon observations of a distinct pattern of travel time delays, waveform distortions, and amplitude patterns which reveal a circular anomaly about 5° across which can be modeled synthetically as a dome about 400 km high with a low shear velocity reduction of ~5%. Numerical modeling indicates that

  7. Unaccompanied Children Migrating from Central America: Public Health Implications for Violence Prevention and Intervention.

    Science.gov (United States)

    Estefan, Lianne Fuino; Ports, Katie A; Hipp, Tracy

    2017-04-01

    Unaccompanied children (UC) migrating to the USA from the Central American countries of El Salvador, Guatemala, and Honduras are an underserved population at high risk for health, academic, and social problems. These children experience trauma, violence, and other risk factors that are shared among several types of interpersonal violence. The trauma and violence experienced by many unaccompanied children, and the subsequent implications for their healthy development into adulthood, indicate the critical need for a public health approach to prevention and intervention. This paper provides an overview of the violence experienced by unaccompanied children along their migration journey, the implications of violence and trauma for the health and well-being of the children across their lifespan, prevention and intervention approaches for UC resettled in the USA, and suggestions for adapted interventions to best address the unique needs of this vulnerable population.

  8. Analysing the geographies of the 'transnational' gangs of Central America: the changing spaces of violence

    Directory of Open Access Journals (Sweden)

    Alisa Winton

    2012-11-01

    Full Text Available The aim of this paper is to contribute to knowledge of 'transnational' youth gangs in the Central American region, through an analysis of the mutually constitutive processes of identity, space and place production. It is argued that insights into gangs gained through analyzing their spatial dynamics and practices, and discussing ways in which these dynamics and processes connect the local and global scales, offer useful knowledge concerning the functioning of these gangs in a field still lacking in–depth academic research. Drawing on over a decade of direct research with young people in the region, the paper finds that poor understanding of gangs inevitably leads to ineffective, counterproductive interventions, and demonstrates that the geographies of maras are a fundamental –and still neglected– aspect of their development and transformation.

  9. Lithospheric expression of geological units in central and eastern North America from full waveform tomography

    Science.gov (United States)

    Yuan, Huaiyu; French, Scott; Cupillard, Paul; Romanowicz, Barbara

    2014-09-01

    The EarthScope TA deployment has provided dense array coverage throughout the continental US and with it, the opportunity for high resolution 3D seismic velocity imaging of both lithosphere and asthenosphere in the continent. Building upon our previous long-period waveform tomographic modeling in North America, we present a higher resolution 3D isotropic and radially anisotropic shear wave velocity model of the North American lithospheric mantle, constructed tomographically using the spectral element method for wavefield computations and waveform data down to 40 s period. The new model exhibits pronounced spatial correlation between lateral variations in seismic velocity and anisotropy and major tectonic units as defined from surface geology. In the center of the continent, the North American craton exhibits uniformly thick lithosphere down to 200-250 km, while major tectonic sutures of Proterozoic age visible in the surface geology extend down to 100-150 km as relatively narrow zones of distinct radial anisotropy, with Vsv >Vsh. Notably, the upper mantle low velocity zone is present everywhere under the craton between 200 and 300 km depth. East of the continental rift margin, the lithosphere is broken up into a series of large, somewhat thinner (150 km) high velocity blocks, which extend laterally 200-300 km offshore into the Atlantic Ocean. Between the craton and these deep-rooted blocks, we find a prominent narrow band of low velocities that roughly follows the southern and eastern Laurentia rift margin and extends into New England. We suggest that the lithosphere along this band of low velocities may be thinned due to the combined effects of repeated rifting processes and northward extension of the hotspot related Bermuda low-velocity channel across the New England region. We propose that the deep rooted high velocity blocks east of the Laurentia margin represent the Proterozoic Gondwanian terranes of pan-African affinity, which were captured during the Rodinia

  10. Temporal patterns and geographic heterogeneity of Zika virus (ZIKV outbreaks in French Polynesia and Central America

    Directory of Open Access Journals (Sweden)

    Ying-Hen Hsieh

    2017-03-01

    Full Text Available Background Zika virus (ZIKV transmission has been reported in 67 countries/territories in the Oceania region and the Americas since 2015, prompting the World Health Organization (WHO to declare ZIKV as a Public Health Emergency of International Concern in February 2016, due to its strong association with medical complications such as microcephaly and Guillain–Barré Syndrome (GBS. However, a substantial gap in knowledge still exists regarding differing temporal pattern and potential of transmission of ZIKV in different regions of the world. Methods We use a phenomenological model to ascertain the temporal patterns and transmission potential of ZIKV in various countries/territories, by fitting the model to Zika case data from Yap Island and French Polynesia in the Oceania region and 11 countries/territories with confirmed case data, namely, Colombia, Ecuador, French Guiana, Guadeloupe, Guatemala, Mexico, Nicaragua, Panama, Puerto Rico, Saint Martin, and Suriname, to pinpoint the waves of infections in each country/territory and to estimate the respective basic reproduction number R0. Results Six of these time series datasets resulted in statistically significant model fit of at least one wave of reported cases, namely that of French Polynesia, Colombia, Puerto Rico, Guatemala, Suriname and Saint Martin. However, only Colombia and Guatemala exhibited two waves of cases while the others had only one wave. Temporal patterns of the second wave in Colombia and the single wave in Suriname are very similar, with the respective turning points separated by merely a week. Moreover, the mean estimates of R0 for Colombia, Guatemala and Suriname, all land-based populations, range between 1.05 and 1.75, while the corresponding mean estimates for R0 of island populations in French Polynesia, Puerto Rico and Saint Martin are significantly lower with a range of 5.70–6.89. We also fit the Richards model to Zika case data from six main archipelagos in French

  11. Anxiety and depression during pregnancy in Central America : a cross-sectional study among pregnant women in the developing country Nicaragua

    NARCIS (Netherlands)

    Verbeek, T.; Arjadi, R.; Vendrik, J. J.; Burger, H.; Berger, M. Y.

    2015-01-01

    Background: Around the world, maternal psychopathology during pregnancy is associated with a range of negative consequences for mother and child. Nevertheless, in Central America the magnitude of this public health problem is still unknown. The objective of this first explorative study was to

  12. Health care providers and human trafficking: What do they know, what do they need to know? Findings from the middle East, the Caribbean, and Central America

    NARCIS (Netherlands)

    Viergever, R.F.; West, H.; Borland, R.; Zimmerman, C.

    2015-01-01

    BACKGROUND: Human trafficking is a crime that commonly results in acute and chronic physical and psychological harm. To foster more informed health sector responses to human trafficking, training sessions for health care providers were developed and pilot-tested in the Middle East, Central America,

  13. Discovery of new Ohbayashinema spp. (nematoda: heligomosomoidea) in Ochotona princeps and O. cansus (lagomorpha: ochotonidae) from western North America and central Asia, with considerations of historical biogeography

    Science.gov (United States)

    Three new species of Ohbayashinema (Nematoda, Heligmosomoidea) are described from localities in western North America and central Asia. Two of these species, Ohbayashinema nearctica n. sp and O. aspeira n. sp. are parasitic in American pika, Ochotona princeps. Ohbayashinema nearctica is differentiat...

  14. Estimativas de possiveis recursos de petroleo e gas na America Central e na America do Sul [Estimates of possible petroleum and gas resources in Central American and South America

    Science.gov (United States)

    Schenk, C.S.

    2001-01-01

    O U.S. Geological Survey recentemente completou estimativas de possíveis recursos de petróleo e gás em 130 áreas petrolíferas pré-determinadas no mundo (USGS, 2000). Vinte e três destas áreas ficam na América do Sul, na América Central, e no Caribe (fig. 1). Os resultados estão apresentados na tabela 1. Nas 23 áreas, estimamos um total de 105 BBO e um total de 487 TCFG. A região composta de América Central mais América do Sul ficou em terceiro lugar no mundo em termos de possíveis recursos de petróleo e gás. No primeiro lugar ficou o Oriente Médio e no segundo lugar ficou a antiga União Soviética (USGS, 2000). As áreas com maiores probabilidades de encontrar depósitos gigantes de petróleo e gás se localizam nas áreas do Oceano Atlântico começando com a Bacia de Santos no sul até a Bacia Guyana-Suriname no norte. As possibilidades de existirem depósitos gigantes são maiores nas áreas submersas do mar até profundidades de 3,600 m. Diversos depósitos gigantes de petróleo foram descobertos no mar na Bacia de Campos e ainda podem serem encontrados depósitos similares na Bacia de Campos e suas imediações.

  15. Geology of the Pavana geothermal area, Departamento de Choluteca, Honduras, Central America: Field report

    Energy Technology Data Exchange (ETDEWEB)

    Eppler, D.B.; Heiken, G.; Wohletz, K.; Flores, W.; Paredes, J.R.; Duffield, W.A.

    1987-09-01

    The Pavana geothermal area is located in southern Honduras near the Gulf of Fonseca. This region is underlain by late Tertiary volcanic rocks. Within ranges near the geothermal manifestations, the rock sequences is characterized by intermediate to mafic laharic breccias and lavas overlain by silicic tuffs and lavas, which are in turn overlain by intermediate to mafic breccias, lavas, and tuffs. The nearest Quaternary volcanoes are about 40 km to the southwest, where the chain of active Central American volcanoes crosses the mouth of the Gulf of Fonseca. Structure of the Pavana area is dominated by generally northwest-trending, southwest-dipping normal faults. This structure is topographically expressed as northwest-trending escarpments that bound blocks of bedrock separated by asymmetric valleys that contain thin alluvial deposits. Thermal waters apparently issue from normal faults and are interpreted as having been heated during deep circulation along fault zones within a regional environment of elevated heat flow. Natural outflow from the main thermal area is about 3000 l/min of 60/sup 0/C water. Geothermometry of the thermal waters suggests a reservoir base temperature of about 150/sup 0/C.

  16. Reconstructing the timing and dispersion routes of HIV-1 subtype B epidemics in the Caribbean and Central America: a phylogenetic story.

    Science.gov (United States)

    Pagán, Israel; Holguín, Africa

    2013-01-01

    The Caribbean and Central America are among the regions with highest HIV-1B prevalence worldwide. Despite of this high virus burden, little is known about the timing and the migration patterns of HIV-1B in these regions. Migration is one of the major processes shaping the genetic structure of virus populations. Thus, reconstruction of epidemiological network may contribute to understand HIV-1B evolution and reduce virus prevalence. We have investigated the spatio-temporal dynamics of the HIV-1B epidemic in The Caribbean and Central America using 1,610 HIV-1B partial pol sequences from 13 Caribbean and 5 Central American countries. Timing of HIV-1B introduction and virus evolutionary rates, as well as the spatial genetic structure of the HIV-1B populations and the virus migration patterns were inferred. Results revealed that in The Caribbean and Central America most of the HIV-1B variability was generated since the 80 s. At odds with previous data suggesting that Haiti was the origin of the epidemic in The Caribbean, our reconstruction indicated that the virus could have been disseminated from Puerto Rico and Antigua. These two countries connected two distinguishable migration areas corresponding to the (mainly Spanish-colonized) Easter and (mainly British-colonized) Western islands, which indicates that virus migration patterns are determined by geographical barriers and by the movement of human populations among culturally related countries. Similar factors shaped the migration of HIV-1B in Central America. The HIV-1B population was significantly structured according to the country of origin, and the genetic diversity in each country was associated with the virus prevalence in both regions, which suggests that virus populations evolve mainly through genetic drift. Thus, our work contributes to the understanding of HIV-1B evolution and dispersion pattern in the Americas, and its relationship with the geography of the area and the movements of human populations.

  17. 300 years of hydrological records and societal responses to droughts and floods on the Pacific coast of Central America

    Science.gov (United States)

    Guevara-Murua, Alvaro; Williams, Caroline A.; Hendy, Erica J.; Imbach, Pablo

    2018-02-01

    The management of hydrological extremes and impacts on society is inadequately understood because of the combination of short-term hydrological records, an equally short-term assessment of societal responses and the complex multi-directional relationships between the two over longer timescales. Rainfall seasonality and inter-annual variability on the Pacific coast of Central America is high due to the passage of the Inter Tropical Convergence Zone (ITCZ) and the El Niño-Southern Oscillation (ENSO). Here we reconstruct hydrological variability and demonstrate the potential for assessing societal impacts by drawing on documentary sources from the cities of Santiago de Guatemala (now Antigua Guatemala) and Guatemala de la Asunción (now Guatemala City) over the period from 1640 to 1945. City and municipal council meetings provide a rich source of information dating back to the beginning of Spanish colonisation in the 16th century. We use almost continuous sources from 1640 AD onwards, including > 190 volumes of Actas de Cabildo and Actas Municipales (minutes of meetings of the city and municipal councils) held by the Archivo Histórico de la Municipalidad de Antigua Guatemala (AHMAG) and the Archivo General de Centro América (AGCA) in Guatemala City. For this 305-year period (with the exception of a total of 11 years during which the books were either missing or damaged), information relating to Catholic rogation ceremonies and reports of flooding events and crop shortages were used to classify the annual rainy season (May to October) on a five-point scale from very wet to very dry. In total, 12 years of very wet conditions, 25 years of wetter than usual conditions, 34 years of drier conditions and 21 years of very dry conditions were recorded. An extended drier period from the 1640s to the 1740s was identified and two shorter periods (the 1820s and the 1840s) were dominated by dry conditions. Wetter conditions dominated the 1760s-1810s and possibly record more

  18. A taxonomic study of Albizia (Leguminosae: Mimosoideae: Ingeae in Mexico and Central America

    Directory of Open Access Journals (Sweden)

    Rico Arce, María de Lourdes

    2008-12-01

    Full Text Available The genus Albizia is economically and environmentally important because many elements are multipurpose trees. A taxonomic study of 12 Central American and Mexican Albizia species is presented. Identification keys, illustrations and ecological information are provided together with some taxonomic comments. Distribution maps and conservation status are given for each native species in the area. Three epithets are lectotypyfied and three new name combinations are made. An interactive identification electronic key is available from the authors if requested. Full specimen records are available at www.kew.org/herbcat .El género Albizia tiene importancia económica y ecológica porque en su mayoría está integrado por árboles con usos múltiples. Se presenta un estudio taxonómico para 12 especies con distribución en México y Centro América, se incluyen claves para la identificación de las especies, ilustraciones, mapas de distribución, estados de conservación de las especies nativas del área y comentarios ecológicos y taxonómicos. Se formaliza la lectipificacion de tres epítetos y se proponen tres nuevas combinaciones. Una clave electrónica interactiva para la identificación de las especies se puede solicitar a los autores. Finalmente el conjunto completo de los ejemplares de herbario puede ser consultado en el sitio Web de los Jardines Reales de Kew: www.kew.org/herbcat.

  19. Treatment of childhood acute lymphoblastic leukemia in central America: a lower-middle income countries experience.

    Science.gov (United States)

    Navarrete, M; Rossi, E; Brivio, E; Carrillo, J M; Bonilla, M; Vasquez, R; Peña, A; Fu, L; Martinez, R; Espinoza, C M Pacheco; Lacayo, L F Baez; Rodriguez, H; Batista, R; Barr, R; Howard, S C; Ribeiro, R C; Masera, G; Biondi, A; Conter, V; Valsecchi, M G

    2014-05-01

    Five Asociación de Hemato-Oncología de Centroamérica (AHOPCA) countries have used an adapted BFM-based protocol for childhood acute lymphoblastic leukemia (ALL). In the AHOPCA-ALL 2008 protocol, patients were stratified by age, white blood cell count, immunophenotype, central nervous system involvement, day 8 prednisone response, and morphologic bone marrow response to induction therapy. Patients at Standard Risk (SR) received a three-drug induction regimen, a reinduction phase, and maintenance with protracted intrathecal therapy. Those at Intermediate (IR) and High Risk (HR) received, in addition, daunorubicin during induction therapy, a consolidation phase and two or three reinduction phases respectively. From August 2008 through July 2012, 1,313 patients were enrolled: 353 in SR, 548 in IR, 412 in HR. During induction therapy, 3.0% of patients died, 2.7% abandoned treatment, 1.1% had resistant ALL, and 93.2% achieved morphological complete remission (CR). Deaths and abandonment in first CR occurred in 2.7% and in 7.0% of patients, respectively. The relapse rate at a median observation time of 2.1 years was 15.0%. At 3 years, the event-free survival (EFS) and overall survival (OS), with abandonment considered as an event, were 59.4% (SE 1.7) and 68.2% (SE 1.6). Three-year EFS was 68.5% (SE 3.0), 62.1% (SE 2.6), and 47.8% (SE 3.2) for SR, IR, and HR groups. Adolescents had a significantly higher relapse rate (P = 0.001). This experience shows that common international studies are feasible in lower-middle income countries. Toxic deaths, abandonment of treatment, and relapses remain major obstacles to the successful treatment. Alternative treatment strategies may be beneficial. © 2013 Wiley Periodicals, Inc.

  20. Southern Hemisphere humpback whales wintering off Central America: insights from water temperature into the longest mammalian migration.

    Science.gov (United States)

    Rasmussen, Kristin; Palacios, Daniel M; Calambokidis, John; Saborío, Marco T; Dalla Rosa, Luciano; Secchi, Eduardo R; Steiger, Gretchen H; Allen, Judith M; Stone, Gregory S

    2007-06-22

    We report on a wintering area off the Pacific coast of Central America for humpback whales (Megaptera novaeangliae) migrating from feeding areas off Antarctica. We document seven individuals, including a mother/calf pair, that made this migration (approx. 8300km), the longest movement undertaken by any mammal. Whales were observed as far north as 11 degrees N off Costa Rica, in an area also used by a boreal population during the opposite winter season, resulting in unique spatial overlap between Northern and Southern Hemisphere populations. The occurrence of such a northerly wintering area is coincident with the development of an equatorial tongue of cold water in the eastern South Pacific, a pattern that is repeated in the eastern South Atlantic. A survey of location and water temperature at the wintering areas worldwide indicates that they are found in warm waters (21.1-28.3 degrees C), irrespective of latitude. We contend that while availability of suitable reproductive habitat in the wintering areas is important at the fine scale, water temperature influences whale distribution at the basin scale. Calf development in warm water may lead to larger adult size and increased reproductive success, a strategy that supports the energy conservation hypothesis as a reason for migration.

  1. Migrants and asylum seekers: policy responses in the United States to immigrants and refugees from Central America and the Caribbean.

    Science.gov (United States)

    Mcbride, M J

    1999-01-01

    This article analyzes the complex political environment of US immigration and refugee policies in which tensions exist, especially with regard to Central America and the Caribbean. Recommendations for managing it more effectively in the future are discussed. Several western countries, including the US, have implemented stricter restriction policies as a result of the perceived threats to their economies and cultural homogeneity. In general, US immigration policy has addressed both economic concerns and domestic pressures, whereas US refugee policy has reflected foreign policy concerns. As a result of these policies, there has been an increasing number of immigrants from Mexico, as well as huge numbers of refugees from Cuba and Nicaragua. Yet, there has been limited acceptance of asylum seekers from Haiti, El Salvador and Guatemala. Among the policies passed by the US Congress to reduce illegal immigration and limit assistance to legal immigrants were the Welfare Reform Act, Illegal Immigration Reform, Immigration Responsibility Act of 1996, and the Proposition 187 movement. Revisions in the procedures of the Immigration and Naturalization Service were also made.

  2. Five cases of acute Zika virus infection in French women of reproductive age returning from Central and South America.

    Science.gov (United States)

    Penot, P; Balavoine, S; Leplatois, A; Brichler, S; Leparc-Goffart, I; Alloui, A-C; Flusin, O; Guilleminot, J; Amellou, M; Molina, J-M

    2017-08-01

    The favorable season for Aedes albopictus circulation has started in Europe and may lead to autochthonous transmission of Zika virus. Health care providers should be familiar with evocative clinical presentations and able to give updated information to women of reproductive age infected by Zika virus. We report five laboratory-confirmed Zika virus infections imported to metropolitan France from Central and South America between January and April, 2016. The five young women were not connected and not pregnant; common presentation combined a rash with persistent arthralgia. Zika virus was identified by RT-PCR from serum or urines, between two and eight days after the onset of the symptoms. As the duration of potential materno-foetal infectivity is still unknown, we were unable to answer with certitude to the patients' questions about the time interval to respect before attempting a pregnancy: one of them became pregnant one month after the diagnosis. Copyright © 2016 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  3. Porphyry copper assessment of Central America and the Caribbean Basin: Chapter I in Global mineral resource assessment

    Science.gov (United States)

    Gray, Floyd; Hammarstrom, Jane M.; Ludington, Stephen; Zürcher, Lukas; Nelson, Carl E.; Robinson, Gilpin R.; Miller, Robert J.; Moring, Barry C.

    2014-01-01

    Mineral resource assessments provide a synthesis of available information about distributions of mineral deposits in the Earth’s crust. The U.S. Geological Survey prepared a probabilistic mineral resource assessment of undiscovered resources in porphyry copper deposits in Central America and the Caribbean Basin in collaboration with geoscientists from academia and the minerals industry. The purpose of the study was to (1) delineate permissive areas (tracts) for undiscovered porphyry copper deposits within 1 kilometer of the surface at a scale of 1:1,000,000; (2) provide a database of known porphyry copper deposits and significant prospects; (3) estimate numbers of undiscovered deposits within the permissive tracts; and (4) provide probabilistic estimates of amounts of copper, molybdenum, gold, and silver that could be contained in undiscovered deposits. The assessment was done using a three-part mineral resource assessment based on established mineral deposit models. Permissive tracts were delineated based primarily on distributions of mapped igneous rocks related to magmatic arcs that formed in tectonic settings associated with convergent plate margins. Five permissive tracts were delineated: the Early Cretaceous through Eocene Santiago tract, the Late Cretaceous through Oligocene Chortis tract, the Paleocene through Oligocene Darién tract, the Miocene and Pliocene Cocos tract, and the Eocene to Holocene Lesser Antilles tract. These tracts range in size from about 3,000 to about 204,000 square kilometers.

  4. Base-level Response to Holocene Climate Change in the Central Appalachian Mountains of North America: Preview of Global Warming?

    Science.gov (United States)

    Springer, G. S.; Rowe, H. D.; Cocina, F. G.; Hardt, B.; Cheng, H.; Edwards, R. L.

    2007-12-01

    Global Warming is expected to bring about substantive changes in global precipitation patterns, which will lead to altered stream hydrologies. The directions and magnitudes of streamflow changes can be inferred from climate projections, but changes in stream architecture and base level are open questions. We address base level response to climate change by reconstructing river behavior during the mid- to late Holocene, including the Hypsithermal when peak Holocene temperatures were achieved. We reconstruct the climate of the Greenbrier River watershed of the central Appalachian Mountains of North America using the stable isotope geochemistry of a stalagmite, cave sediments, and published pollen data. Independently, we construct a history of base level position using cave sediments deposited by the river. Stalagmite values of δ18O and δ13C are heavy during the Hypsithermal, which pollen results indicate was warm and dry compared to the rest of the Holocene. Cave sediments deposited by the Greenbrier River record base level as having been below the cave during the early and late Holocene, but above the cave during the Hypsithermal. The mid-Holocene base level rise is attributed to infilling of the channel with as much as 4 m of sediment, presumably a response to changes in storm frequency and stream hydrology. Global Warming will cause temperatures to exceed those of the Hypsithermal. Flood zones will extend to higher elevations and flood risks and vulnerabilities will increase dramatically if Appalachian rivers respond to Global Warming as the Greenbrier River did to the Hypsithermal.

  5. The performance of RegCM4 over the Central America and Caribbean region using different cumulus parameterizations

    Science.gov (United States)

    Martínez-Castro, Daniel; Vichot-Llano, Alejandro; Bezanilla-Morlot, Arnoldo; Centella-Artola, Abel; Campbell, Jayaka; Giorgi, Filippo; Viloria-Holguin, Cecilia C.

    2017-09-01

    A sensitivity study of the performance of the RegCM4 regional climate model driven by the ERA Interim reanalysis is conducted for the Central America and Caribbean region. A set of numerical experiments are completed using four configurations of the model, with a horizontal grid spacing of 25 km for a period of 6 years (1998-2003), using three of the convective parameterization schemes implemented in the model, the Emanuel scheme, the Grell over land-Emanuel over ocean scheme and two configurations of the Tiedtke scheme. The objective of the study is to investigate the ability of each configuration to reproduce different characteristics of the temperature, circulation and precipitation fields for the dry and rainy seasons. All schemes simulate the general temperature and precipitation patterns over land reasonably well, with relatively high correlations compared to observation datasets, though in specific regions there are positive or negative biases, greater in the rainy season. We also focus on some circulation features relevant for the region, such as the Caribbean low level jet and sea breeze circulations over islands, which are simulated by the model with varied performance across the different configurations. We find that no model configuration assessed is best performing for all the analysis criteria selected, but the Tiedtke configurations, which include the capability of tuning in particular the exchanges between cloud and environment air, provide the most balanced range of biases across variables, with no outstanding systematic bias emerging.

  6. Herbarium specimens reveal the footprint of climate change on flowering trends across north-central North America.

    Science.gov (United States)

    Calinger, Kellen M; Queenborough, Simon; Curtis, Peter S

    2013-08-01

    Shifting flowering phenology with rising temperatures is occurring worldwide, but the rarity of co-occurring long-term observational and temperature records has hindered the evaluation of phenological responsiveness in many species and across large spatial scales. We used herbarium specimens combined with historic temperature data to examine the impact of climate change on flowering trends in 141 species collected across 116,000 km(2) in north-central North America. On average, date of maximum flowering advanced 2.4 days °C(-1), although species-specific responses varied from - 13.5 to + 7.3 days °C(-1). Plant functional types exhibited distinct patterns of phenological responsiveness with significant differences between native and introduced species, among flowering seasons, and between wind- and biotically pollinated species. This study is the first to assess large-scale patterns of phenological responsiveness with broad species representation and is an important step towards understanding current and future impacts of climate change on species performance and biodiversity. © 2013 The Authors. Ecology Letters published by John Wiley & Sons Ltd and CNRS.

  7. Invasion of the Indo-Pacific blenny Omobranchus punctatus (Perciformes: Blenniidae on the Atlantic Coast of Central and South America

    Directory of Open Access Journals (Sweden)

    Oscar Lasso-Alcalá

    Full Text Available We examined 308 specimens of the Indo-Pacific blenniid Omobranchus punctatus deposited in four museum collections, and analyzed data on their collection locations to assess its invasion on the Atlantic coast of Central and South America. This species occurs in shoreline estuarine and marine habitats in the Indo-West Pacific. Previous sampling and recent records in the Tropical West Atlantic from 1930 to 2004 produced 20 records for: Panamá, Colombia, Venezuela, Trinidad and Brazil. In this work, we provide data on 17 new records for the Gulfs of Venezuela and Paria in Venezuela, as well as four records for Maranhão and Pará states in NE Brazil. The temporal pattern of collections (1930 - 2009 and the proximity of most localities to ports and zones of ship traffic indicate that O. punctatus was initially introduced to the Atlantic by ships travelling from India to Trinidad. Within Brazil the introduction is linked to shipping connected to petroleum platforms. In Maranhão and Pará the introduction may have occurred as a result of fish sheltering in fouling on hulls of ships moving between ports around the mouth of the Amazon River. Alternatively, the spread of this species along of the American coast may reflect the expansion of the range of O. puntactus through larval dispersal in northward flowing currents. We recommend monitoring of this introduced species, and studies of its ecology in West Atlantic areas.

  8. Phenotypic and genotypic heterogeneity among Streptococcus iniae isolates recovered from cultured and wild fish in North America, Central America and the Caribbean Islands

    Science.gov (United States)

    Streptococcus iniae, the etiological agent of streptococcosis in fish, is an important pathogen of cultured and wild fish worldwide. During the last decade outbreaks of streptococcosis have occurred in a wide range of cultured and wild fish in the Americas and Caribbean islands. To gain a better und...

  9. Cold episodes in the Peruvian Central Andes: Composites, Types, and their Impacts over South America (1958-2014)

    Science.gov (United States)

    Sulca, J. C.; Vuille, M. F.; Roundy, P. E.; Trasmonte, G.; Silva, Y.; Takahashi, K.

    2015-12-01

    The Mantaro basin (MB) is located in the central Peruvian Andes. Occasionally, cold episodes are observed during austral summer (January-March), that strongly damage crops. However, little is known about the causes and impacts of such cold episodes. The main goal of this study is thus to characterize cold episodes in the MB and assess their large-scale circulation and teleconnections over South America (SA) during austral summer. To identify cold events in the MB daily minimum temperature (Tmin) for the period 1958-2014 from Huayao station, located within the MB was used. A cold episode is defined when daily minimum temperature drops below its 10-percentile for at least one day. Additionally, to study the sensitivity between physical mechanisms associated with cold episodes and temperature, cold episodes are classified in three groups: Weak cold episodes (7.5 ≤ Tmin ≤ 10 percentile), strong cold episodes (Tmin ≤ 2.5 percentile), but excluding the 9 coldest events (Tmin ≤ 0 ͦ C), henceforth referred to as extraordinary cold episodes. Several gridded reanalysis were used to characterize the large-scale circulation, cloud cover and rainfall over SA associated with these events. Weak and strong cold episodes in the MB are mainly associated with a weakening of the Bolivian High-Nordeste Low system by tropical-extratropical interactions. Both types of cold episodes are associated with westerly wind anomalies at mid- and upper-tropospheric levels aloft the Peruvian Central Andes, which inhibit the influx of humid air masses from the lowlands to the east and hence limit the development of cloud cover (e.g., positive OLR anomalies over MB). The resulting clear sky conditions cause nighttime temperatures to drop, leading to cold extremes below 10-percentile. Simultaneously, northeastern Brazil (NEB) registers negative OLR anomalies, strong convection and enhanced cloud cover because displacement of the South Atlantic Convergence Zone (SACZ) toward the northeast of

  10. Adjusting central and eastern North America ground‐motion intensity measures between sites with different reference‐rock site conditions

    Science.gov (United States)

    Boore, David; Campbell, Kenneth W.

    2017-01-01

    Adjustment factors are provided for converting ground‐motion intensity measures between central and eastern North America (CENA) sites with different reference‐rock site conditions (VS30=760, 2000, and 3000  m/s) for moment magnitudes ranging from 2 to 8, rupture distances ranging from 2 to 1200 km, Fourier amplitude spectra (FAS) for frequencies ranging from 0.01 to 100 Hz, response spectra for periods ranging from 0.01 to 10.0 s, peak ground acceleration, and peak ground velocity. The adjustment factors are given for a wide range of the site diminution parameters (κ0) for sites with VS30=760  m/s and for a κ0 of 0.006 s for two harder rock sites. Fourteen CENA velocity profiles with VS30 values within a factor of 1.1 of 760  m/s were used to derive average FAS amplification factors as a function of frequency, which were then used in simulations of peak ground‐motion parameters and response spectra to derive the adjustment factors. The amplification function differs from that used in western North America (e.g., Campbell and Boore, 2016) in having a peak near 9 Hz, due to the resonance of motions in the relatively thin low‐velocity material over hard rock that characterizes many CENA sites with VS30 near 760  m/s. We call these B/C sites, because this velocity marks the boundary between National Earthquake Hazards Reduction Program site classes B and C (Building Seismic Safety Council, 2004). The adjustments for short‐period motions are sensitive to the value of κ0, but there are very few if any determinations of κ0 for CENA B/C sites. For this reason, we determined κ0 from multiple recordings at Pinyon Flat Observatory (PFO), California, which has a velocity‐depth profile similar to those of CENA B/C sites. The PFO and other results from the literature suggest that appropriate values of κ0 for CENA B/C sites are expected to lie between 0.01 and 0.03 s.

  11. Adjusting central and eastern North America ground-motion intensity measures between sites with different reference-rock site conditions

    Science.gov (United States)

    Boore, David; Campbell, Kenneth W.

    2017-01-01

    Adjustment factors are provided for converting ground‐motion intensity measures between central and eastern North America (CENA) sites with different reference‐rock site conditions (VS30=760, 2000, and 3000  m/s) for moment magnitudes ranging from 2 to 8, rupture distances ranging from 2 to 1200 km, Fourier amplitude spectra (FAS) for frequencies ranging from 0.01 to 100 Hz, response spectra for periods ranging from 0.01 to 10.0 s, peak ground acceleration, and peak ground velocity. The adjustment factors are given for a wide range of the site diminution parameters (κ0) for sites with VS30=760  m/s and for a κ0 of 0.006 s for two harder rock sites. Fourteen CENA velocity profiles with VS30 values within a factor of 1.1 of 760  m/s were used to derive average FAS amplification factors as a function of frequency, which were then used in simulations of peak ground‐motion parameters and response spectra to derive the adjustment factors. The amplification function differs from that used in western North America (e.g., Campbell and Boore, 2016) in having a peak near 9 Hz, due to the resonance of motions in the relatively thin low‐velocity material over hard rock that characterizes many CENA sites with VS30 near 760  m/s. We call these B/C sites, because this velocity marks the boundary between National Earthquake Hazards Reduction Program site classes B and C (Building Seismic Safety Council, 2004). The adjustments for short‐period motions are sensitive to the value of κ0, but there are very few if any determinations of κ0 for CENA B/C sites. For this reason, we determined κ0from multiple recordings at Pinyon Flat Observatory (PFO), California, which has a velocity‐depth profile similar to those of CENA B/C sites. The PFO and other results from the literature suggest that appropriate values of κ0 for CENA B/C sites are expected to lie between 0.01 and 0.03 s.

  12. Profiles of Central America.

    Science.gov (United States)

    Interracial Books for Children Bulletin, 1982

    1982-01-01

    In order to provide information missing from elementary and secondary educational materials, briefly reviews the history, geography, and current political, economic, demographic, and social characteristics of El Salvador, Guatemala, Honduras, and Nicaragua. Some information is also given about Costa Rica, Panama, and Belize.

  13. Gangs in Central America

    Science.gov (United States)

    2005-05-10

    the root causes of gang violence, which include poverty, joblessness , and the social exclusion of at-risk youth , are addressed in a holistic manner...the Mara Salvatrucha (MS-13). The 18th Street gang was formed by Mexican immigrants in the Rampart section of Los Angeles in the 1960s, youth who were...populations; growing youth populations facing stagnant job markets; and an absence of political will to fight crime in a holistic manner. Some

  14. Biofuels in Central America

    International Nuclear Information System (INIS)

    Sanders, E.

    2007-08-01

    This report presents the results of an analysis of the biofuel markets in El Salvador, Panama, Costa Rica and Honduras. The aim of this report is to provide insight in the current situation and the expected developments in these markets and thus to provide investors with an image of the opportunities that could be present in this sector. An attempt has been made to provide a clear overview of this sector in the countries concerned. Due to a lack of data this has not been fully accomplished in some cases. [mk] [nl

  15. Assessing and mapping drought hazard in Africa and South-Central America with a Meteorological Drought Severity Index

    Science.gov (United States)

    Carrao, Hugo; Barbosa, Paulo; Vogt, Jürgen

    2015-04-01

    the intra-annual variability of precipitation in estimating the severity of events that can impact on seasonal activities. The MDSI is standardized in space and time, and considers the relative monthly precipitation deficits and the seasonal influence of precipitation regimes in the meteorological drought severity computation. In this study, the calculation of the MDSI is performed with monthly precipitation totals from the Full Data Reanalysis Monthly Product Version 6.0 of the Global Precipitation Climatology Centre (GPCC). This dataset provides a global analysis at 0.5 dd latitude/longitude grid spacing of monthly precipitation over land from operational in situ rain gauges collected between January 1901 and December 2010. Using the MDSI, we estimated the severity of drought events that occurred in the past 100 years in Africa and South-Central America, and produced drought hazard maps based on the probability of exceedance the median historical severity. Overall, results indicate that drought hazard is high for semiarid areas, such as Northeastern and Southern South America, as well as Eastern and Southwestern Africa. Since available water resources in semiarid areas are already insufficient to permanently meet the demands of human activities, the outcomes highlight the aggravated risk for food security and confirm the need for the implementation of disaster mitigation measures in those regions.

  16. The effect of the low-level jet on the poleward water vapour transport in the central region of South America

    Science.gov (United States)

    Berri, Guillermo J.; Inzunza, Juan B.

    The low-level jet (LLJ) in the central region of South America is studied. This LLJ is generated by the daily cycle of convergence and divergence east of the Andes Mountains. We use the 1973-1974 radiosonde and pilot balloon data set from the upper air weather stations, Salta and Resistencia, in northern Argentina to select 10 LLJ cases and another 10 NoLLJ cases (when the LLJ is not present). We use the University of Utah Mesoscale Model to simulate these situations in order to obtain a high-resolution low-level wind field. These model predictions are then used to calculate the meridional water vapour transport across a vertical cross-section, along 26°S in central South America. The results reveal that the LLJs are a very effective mechanism for the poleward water vapour transport.

  17. LCE: leaf carbon exchange data set for tropical, temperate, and boreal species of North and Central America.

    Science.gov (United States)

    Smith, Nicholas G; Dukes, Jeffrey S

    2017-11-01

    Leaf canopy carbon exchange processes, such as photosynthesis and respiration, are substantial components of the global carbon cycle. Climate models base their simulations of photosynthesis and respiration on an empirical understanding of the underlying biochemical processes, and the responses of those processes to environmental drivers. As such, data spanning large spatial scales are needed to evaluate and parameterize these models. Here, we present data on four important biochemical parameters defining leaf carbon exchange processes from 626 individuals of 98 species at 12 North and Central American sites spanning ~53° of latitude. The four parameters are the maximum rate of Rubisco carboxylation (V cmax ), the maximum rate of electron transport for the regeneration of Ribulose-1,5,-bisphosphate (J max ), the maximum rate of phosphoenolpyruvate carboxylase carboxylation (V pmax ), and leaf dark respiration (R d ). The raw net photosynthesis by intercellular CO 2 (A/C i ) data used to calculate V cmax , J max , and V pmax rates are also presented. Data were gathered on the same leaf of each individual (one leaf per individual), allowing for the examination of each parameter relative to others. Additionally, the data set contains a number of covariates for the plants measured. Covariate data include (1) leaf-level traits (leaf mass, leaf area, leaf nitrogen and carbon content, predawn leaf water potential), (2) plant-level traits (plant height for herbaceous individuals and diameter at breast height for trees), (3) soil moisture at the time of measurement, (4) air temperature from nearby weather stations for the day of measurement and each of the 90 d prior to measurement, and (5) climate data (growing season mean temperature, precipitation, photosynthetically active radiation, vapor pressure deficit, and aridity index). We hope that the data will be useful for obtaining greater understanding of the abiotic and biotic determinants of these important biochemical

  18. Origins and biogeography of the Anolis crassulus subgroup (Squamata: Dactyloidae) in the highlands of Nuclear Central America.

    Science.gov (United States)

    Hofmann, Erich P; Townsend, Josiah H

    2017-12-21

    Recent studies have begun to reveal the complex evolutionary and biogeographic histories of mainland anoles in Central America, but the origins and relationships of many taxa remain poorly understood. One such group is the Anolis (Norops) crassulus species subgroup, which contains ten morphologically similar highland taxa, the majority of which have restricted distributions. The nominal taxon A. crassulus has a disjunct distribution from Chiapas, Mexico, through Guatemala, in the highlands of El Salvador, and in the Chortís Highlands of Honduras. We test the relationships of these species using multiple mitochondrial and nuclear loci in concatenated and multispecies coalescent frameworks, in an effort to both resolve long-standing taxonomic confusion and present new insights into the evolution and biogeography of these taxa. Sequences of multiple mitochondrial and nuclear loci were generated for eight of the ten species of the Anolis crassulus species subgroup. We analyzed phylogenetic relationships and estimated divergence times and ancestral ranges of the subgroup, recovering a monophyletic subgroup within Anolis. Within the nominal taxon Anolis crassulus, we recovered multiple genetically distinct lineages corresponding to allopatric populations, and show that the Chortís Highland lineage split from the others over 13 MYA. Additionally, distinct mitochondrial lineages are present within the taxa A. heteropholidotus and A. morazani, and importantly, samples of A. crassulus and A. sminthus previously used in major anole phylogenetic analyses are not recovered as conspecific with those taxa. We infer a Chortís Highland origin for the ancestor of this subgroup, and estimate cladogenesis of this subgroup began approximately 22 MYA. Our results provide new insights into the evolution, biogeography, and timing of diversification of the Anolis crassulus species subgroup. The disjunctly distributed Anolis crassulus sensu lato represents several morphologically

  19. Geochemical Constraints on the pre-Cenozoic Subduction History of two Margins of the Chortis Block (Northern Central America)

    Science.gov (United States)

    Geldmacher, J.; Martens, U.; Hoernle, K.; Hauff, F.; Bogaard, P.; Kluegel, A.

    2007-12-01

    The igneous forearc basement along the Pacific coast of northern Central America (between southern Mexico and Costa Rica) comprises a highly tectonized accretionary assemblage of igneous and ultramafic rocks. Volcanic and gabbroic rocks with primitive arc geochemical signatures formed between ~100 and ~180 Ma and are interpreted to have originated by arc magmatism resulting from subduction of the Pacific/Farallon plate. Additionally, the forearc contains geochemically enriched ocean island basalt (OIB)-like units that are interpreted as accreted seamounts and islands of a 100 to ~220 Ma old hotspot track, which most likely originated from a long-extinct hotspot located in the Pacific. Based on their combined Pb, Nd, Hf isotopic compositions an affiliation of these isotopically strongly enriched rocks with the Caribbean Large Igneous Province or the Galápagos hotspot appears unlikely. Rocks of similar age and geochemistry are exposed in the Santa Elena Peninsula of Costa Rica, suggesting that the same type of forearc basement is accreted to the continental Chortis block all the way from southern Mexico to Costa Rica. In contrast, gabbroic rocks of the Motagua suture zone in central Guatemala (El Tambor accretionary complex) show depleted MORB signatures and have igneous ages of ~130Ma. These MOR Gabbros were accreted on the current northern margin of the Chortis block during subduction of proto-Caribbean crust. In contrast, geochemistry of gabbros and diorites of the Sierra de Santa Cruz (SSC) indicate medium to high K-series arc affinity and their Ar/Ar ages range from ~75 to 130 Ma. The SSC is interpreted as the western extension of the early Cuban arc that collided with the Maya block in the latest Cretaceous. Arc-derived volcanic clasts were subsequently shed into the Paleocene Sepur Formation of the Maya block. No evidence of accretion of OIB-like material was found in the Motagua suture or the SSC so far. These new data suggest that proto-Caribbean crust

  20. A renewed sense for the purposes of schooling: the challenges of education and social cohesion in Asia, Africa, Latin America, Europe and Central Asia

    OpenAIRE

    P. Heyneman, Stephen; Todoric-Bebic, Sanja

    2012-01-01

    This paper summarizes the experience in meeting the challenges of social cohesion — and hence economic development — in countries such as Africa, Asia, Latin America, Europe and Central Asia. The relations between education and social cohesion in the different regions above mentioned are also analized. The authors discuss mainly ethnic and public corruption problems linked to social cohesion: and consider that the social cohesion is at the heart of each nation's education system, as much...

  1. A new species of Charinus Simon, 1892 from northeastern Brazil with comments on the potential distribution of the genus in Central and South Americas (Arachnida: Amblypygi: Charinidae).

    Science.gov (United States)

    Vasconcelos, Ana Caroline Oliveira; Giupponi, Alessandro Ponce De Leão; Ferreira, Rodrigo Lopes

    2013-11-21

    A new species of the genus Charinus Simon, 1892 is described from caves in the Rio Grande do Norte, Brazil. This is the first record of the genus for the state. This paper presents a map of the Charinus species distribution in Brazil with new records and a map of potential distribution of the genus in South and Central Americas. An updated key for Charinus species from Brazil is also presented.

  2. Data on medicinal plants used in Central America to manage diabetes and its sequelae (skin conditions, cardiovascular disease, kidney disease, urinary problems and vision loss

    Directory of Open Access Journals (Sweden)

    Peter Giovannini

    2016-06-01

    Full Text Available The data described in this article is related to the review article “Medicinal plants used in the traditional management of diabetes and its sequelae in Central America: a review” (Giovannini et al., 2016 [1]. We searched publications on the useful plants of Central America in databases and journals by using selected relevant keywords. We then extracted reported uses of medicinal plants within the disease categories: diabetes mellitus, kidney disease, urinary problems, skin diseases and infections, cardiovascular disease, sexual dysfunction, vision loss, and nerve damage. The following countries were included in our definition of Central America: Belize, Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica and Panama. Data were compiled in a bespoke Access database. Plant names from the published sources were validated against The Plant List (TPL, (The Plant List, 2013 [2] and accepted names and synonyms were extracted. In total, the database includes 607 plant names obtained from the published sources which correspond to 537 plant taxa, 9271 synonyms and 1055 use reports.

  3. Constraints on seismic anisotropy beneath the Appalachian Mountains from Love-to-Rayleigh wave scattering

    Science.gov (United States)

    Servali, A.; Long, M. D.; Benoit, M.

    2017-12-01

    The eastern margin of North America has been affected by a series of mountain building and rifting events that have likely shaped the deep structure of the lithosphere. Observations of seismic anisotropy can provide insight into lithospheric deformation associated with these past tectonic events, as well as into present-day patterns of mantle flow beneath the passive margin. Previous work on SKS splitting beneath eastern North America has revealed fast splitting directions parallel to the strike of the Appalachian orogen in the central and southern Appalachians. A major challenge to the interpretation of SKS splitting measurements, however, is the lack of vertical resolution; isolating anisotropic structures at different depths is therefore difficult. Complementary constraints on the depth distribution of anisotropy can be provided by surface waves. In this study, we analyze the scattering of Love wave energy to Rayleigh waves, which is generated via sharp lateral gradients in anisotropic structure along the ray path. The scattered phases, known as quasi-Love (QL) waves, exhibit amplitude behavior that depend on the strength of the anisotropic contrast as well as the angle between the propagation azimuth and the anisotropic symmetry axis. We analyze data collected by the dense MAGIC seismic array across the central Appalachians. We examine teleseismic earthquakes of magnitude 6.7 and greater over a range of backazimuths, and isolate surface waves at periods between 100 and 500 seconds. We compare the data to synthetic seismograms generated by the Princeton Global ShakeMovie initiative to identify anomalous QL arrivals. We find evidence significant QL arrivals at MAGIC stations, with amplitudes depending on propagation azimuth and station location. Preliminary results are consistent with a sharp lateral gradient in seismic anisotropy across the Appalachian Mountains in the depth range between 100-200 km.

  4. Neotectonic development of the El Salvador Fault Zone and implications for deformation in the Central America Volcanic Arc: Insights from 4-D analog modeling experiments

    Science.gov (United States)

    Alonso-Henar, Jorge; Schreurs, Guido; Martinez-Díaz, José Jesús; Álvarez-Gómez, José Antonio; Villamor, Pilar

    2015-01-01

    The El Salvador Fault Zone (ESFZ) is an active, approximately 150 km long and 20 km wide, segmented, dextral strike-slip fault zone within the Central American Volcanic Arc striking N100°E. Although several studies have investigated the surface expression of the ESFZ, little is known about its structure at depth and its kinematic evolution. Structural field data and mapping suggest a phase of extension, at some stage during the evolution of the ESFZ. This phase would explain dip-slip movements on structures that are currently associated with the active, dominantly strike slip and that do not fit with the current tectonic regime. Field observations suggest trenchward migration of the arc. Such an extension and trenchward migration of the volcanic arc could be related to slab rollback of the Cocos plate beneath the Chortis Block during the Miocene/Pliocene. We carried out 4-D analog model experiments to test whether an early phase of extension is required to form the present-day fault pattern in the ESFZ. Our experiments suggest that a two-phase tectonic evolution best explains the ESFZ: an early pure extensional phase linked to a segmented volcanic arc is necessary to form the main structures. This extensional phase is followed by a strike-slip dominated regime, which results in intersegment areas with local transtension and segments with almost pure strike-slip motion. The results of our experiments combined with field data along the Central American Volcanic Arc indicate that the slab rollback intensity beneath the Chortis Block is greater in Nicaragua and decreases westward to Guatemala.

  5. Positive Patch-Test Reactions to Essential Oils in Consecutive Patients From North America and Central Europe.

    Science.gov (United States)

    Warshaw, Erin M; Zug, Kathryn A; Belsito, Donald V; Fowler, Joseph F; DeKoven, Joel G; Sasseville, Denis; Maibach, Howard I; Mathias, C G Toby; DeLeo, Vincent A; Taylor, James S; Fransway, Anthony F; Marks, James G; Pratt, Melanie D; Zirwas, Matthew J; Geier, Johannes; Uter, Wolfgang

    Synthetic fragrances and natural essential oils (EOs) are used in perfumery and found in various cosmetics. Essential oils are also increasingly used to promote wellness. In previous studies, the sensitization potential of some EOs has been identified; however, the current prevalence of sensitivity is largely unknown. The aim of this study was to determine frequency of positive patch-test reactions to EOs tested in the baseline series, along with 3 fragrance markers (FMs) (fragrance mix I, fragrance mix II, and Myroxylon pereirae), in consecutive patients in the US/Canadian North American Contact Dermatitis Group (NACDG) (2009-2014) and the central European, trinational Information Network of Departments of Dermatology (IVDK) (2010-2014). This study used a retrospective analysis of patch-test results and relevant demographic/clinical data collected electronically by the networks, obtained with Santalum album 10% petrolatum (pet) (IVDK only); Cananga odorata 2% (NACDG) and 10% (IVDK) pet; Jasminum species 2% (NACDG) and 5% (IVDK) pet; Mentha piperita 2% pet; Melaleuca alternifolia, oxidized (tea tree oil), 5% pet; and Lavandula angustifolia 2% pet (latter 3 NACDG only). Overall, 62,354 patients were tested to 3 FMs and EOs (NACDG, 13,398; IVDK, 48,956); 11,568 (18.6%) reacted to at least 1 FM or EO, whereas 857 (1.4%) reacted to 1 or more EOs but none of the 3 FMs. For both the NACDG and IVDK populations, individuals who were positive to 1 or more of the 9 study allergens were significantly less likely to be male, have occupational skin disease, or have hand involvement and significantly more likely to have leg dermatitis and be 40 years and older (P's ≤ 0.005). Prevalence rates for EOs were as follows: S. album, 1.4% IVDK; C. odorata, 1.1% NACDG and 2.4% IVDK; Jasminum species, 0.7% NACDG and 1.4% IVDK; M. piperita, 0.9% NACDG; L. angustifolia, 0.3% NACDG; and M. alternifolia, 0.3% NACDG. Of the 140 NACDG patients who reacted to 1 or more of the 5 NACDG EOs but

  6. Linking National Parks with its Gateway Communities for Tourism Development in Central America: Nindiri, Nicaragua, Bagazit, Costa Rica and Portobelo, Panama

    Directory of Open Access Journals (Sweden)

    Aguirre G., J. A.

    2006-01-01

    Full Text Available Protected areas and national parks are becoming one of the most important forms of land use in Central America. All the projections made by the World Tourism Organization seems to agree that by 2010 Central America, maybe receiving between eight and ten millions tourists, a figure that is almost twice what the region is receiving today. A study was conducted base on 369 direct field surveys conducted in three Central American communities: Bagazit gateway community to Palo Verde National Park, Costa Rica, Nindiri, gateway community to Volcan Masaya National Park, Nicaragua and Portobelo, gateway community to Por-tobelo National Park, Panama. The study found that relative to the socio-demographic variables, that there were no significance differences at the 95% probability level in all four variables, age, sex, education and monthly income of the family. Educational level seems to be the socio-demographic variables affecting more the state of relations. The perception variable being has taken into account in the decision that affects the communities and responsibility to help with community problems are present in two of the three models. The perception variables related to tourism, feel trained to take care of the tourist and existence of businesses that can caters to tourist seem to be key elements in the community perception about the state of relation. Tourism related economic activities and community participation in park decisions are today and will be in the future essential elements in the shaping of community/park relations in Central America as tourism becomes a major economic sector in the region economy.

  7. Seismicity of the Earth 1900-2007, Nazca Plate and South America

    Science.gov (United States)

    Rhea, Susan; Hayes, Gavin P.; Villaseñor, Antonio; Furlong, Kevin P.; Tarr, Arthur C.; Benz, Harley

    2010-01-01

    The South American arc extends over 7,000 km, from the Chilean triple junction offshore of southern Chile to its intersection with the Panama fracture zone, offshore the southern coast of Panama in Central America. It marks the plate boundary between the subducting Nazca plate and the South America plate, where the oceanic crust and lithosphere of the Nazca plate begin their decent into the mantle beneath South America. The convergence associated with this subduction process is responsible for the uplift of the Andes Mountains, and for the active volcanic chain present along much of this deformation front. Relative to a fixed South America plate the Nazca plate moves slightly north of eastwards at a rate varying from approximately 80 mm/yr in the south to approximately 70mm/yr in the north.

  8. Shear wave velocity structure in North America from large-scale waveform inversions of surface waves

    Science.gov (United States)

    Alsina, D.; Woodward, R.L.; Snieder, R.K.

    1996-01-01

    A two-step nonlinear and linear inversion is carried out to map the lateral heterogeneity beneath North America using surface wave data. The lateral resolution for most areas of the model is of the order of several hundred kilometers. The most obvious feature in the tomographic images is the rapid transition between low velocities in the technically active region west of the Rocky Mountains and high velocities in the stable central and eastern shield of North America. The model also reveals smaller-scale heterogeneous velocity structures. A high-velocity anomaly is imaged beneath the state of Washington that could be explained as the subducting Juan de Fuca plate beneath the Cascades. A large low-velocity structure extends along the coast from the Mendocino to the Rivera triple junction and to the continental interior across the southwestern United States and northwestern Mexico. Its shape changes notably with depth. This anomaly largely coincides with the part of the margin where no lithosphere is consumed since the subduction has been replaced by a transform fault. Evidence for a discontinuous subduction of the Cocos plate along the Middle American Trench is found. In central Mexico a transition is visible from low velocities across the Trans-Mexican Volcanic Belt (TMVB) to high velocities beneath the Yucatan Peninsula. Two elongated low-velocity anomalies beneath the Yellowstone Plateau and the eastern Snake River Plain volcanic system and beneath central Mexico and the TMVB seem to be associated with magmatism and partial melting. Another low-velocity feature is seen at depths of approximately 200 km beneath Florida and the Atlantic Coastal Plain. The inversion technique used is based on a linear surface wave scattering theory, which gives tomographic images of the relative phase velocity perturbations in four period bands ranging from 40 to 150 s. In order to find a smooth reference model a nonlinear inversion based on ray theory is first performed. After

  9. Geomorphic analysis of transient landscapes from the Sierra Madre de Chiapas and Maya Mountains (northern Central America): implications for the North American-Caribbean-Cocos plate boundary

    Science.gov (United States)

    Andreani, L.; Gloaguen, R.

    2015-09-01

    We use a geomorphic approach in order to unravel the recent evolution of the diffuse triple junction between the North American, Caribbean, and Cocos plates in northern Central America. The complex tectonic setting produced an intricate pattern of landscapes that we try to systemize using remote sensing tectonic geomorphology and available geological and geophysical data. We classify regions with specific relief characteristics and highlight uplifted relict landscapes in northern Central America. We also analyze the drainage network from the Sierra Madre de Chiapas and Maya Mountains in order to extract information about potential vertical displacements. Our results suggest that most of the landscapes of the Sierra Madre de Chiapas and Maya Mountains are in transient stage. Topographic profiles and morphometric maps highlight elevated relict surfaces that are characterized by a low amplitude relief. The river longitudinal profiles display upper reaches witnessing these relict landscapes while lower segments characterized by multiple knickpoints, that adjust to new base-level conditions. These results backed by published GPS and seismotectonic data allow us to refine and extend existing geodynamic models of the triple junction. Relict landscapes are delimited by faults and thus result from a tectonic control. The topography of the Sierra Madre de Chiapas evolved as the result of (1) the inland migration of deformation related to the coupling between the Chiapas Massif and the Cocos fore-arc sliver, and (2) the compression along the northern tip of the Central America Volcanic Arc. Although most of the shortening between the Cocos fore-arc sliver and the North American plate is accommodated within the Sierra de Chiapas and Sierra de los Cuchumatanes, a small part may be still transmitted to the Maya Mountains and the Belize margin through a "rigid" Petén basin.

  10. The 1.1-Ga Midcontinent Rift System, central North America: sedimentology of two deep boreholes, Lake Superior region

    Science.gov (United States)

    Ojakangas, Richard W.; Dickas, Albert B.

    2002-03-01

    The Midcontinent Rift System (MRS) of central North America is a 1.1-Ga, 2500-km long structural feature that has been interpreted as a triple-junction rift developed over a mantle plume. As much as 20 km of subaerial lava flows, mainly flood basalts, are overlain by as much as 10 km of sedimentary rocks that are mostly continental fluvial red beds. This rock sequence, known as the Keweenawan Supergroup, has been penetrated by a few deep boreholes in the search for petroleum. In this paper, two deep boreholes in the Upper Peninsula of Michigan are described in detail for the first time. Both the Amoco Production #1-29R test, herein referred to as the St. Amour well, and the nearby Hickey Creek well drilled by Cleveland Cliffs Mining Services, were 100% cored. The former is 7238 ft (2410 m) deep and the latter is 5345 ft (1780 m) deep. The entirety of the stratigraphic succession of the Hickey Creek core correlates very well with the upper portion of the St. Amour core, as determined by core description and point-counting of 43 thin sections selected out of 100 studied thin sections. Two Lower Paleozoic units and two Keweenawan red bed units—the Jacobsville Sandstone and the underlying Freda Sandstone—are described. The Jacobsville is largely a feldspatholithic sandstone and the Freda is largely a lithofeldspathic sandstone. Below the Freda, the remaining footage of the St. Amour core consists of a thick quartzose sandstone unit that overlies a heterogenous unit of intercalated red bed units of conglomerate, sandstone, siltstone, and shale; black shale; individual basalt flows; and a basal ignimbritic rhyolite. This lower portion of the St. Amour core presents an enigma, as it correlates very poorly with other key boreholes located to the west and southwest. While a black shale sequence is similar to the petroleum-bearing Nonesuch Formation farther west, there is no conglomerate unit to correlate with the Copper Harbor Conglomerate. Other key boreholes are

  11. Educacion y Pueblos Indigenas en Centroamerica: Un Balance Critico (Education and Indigenous People in Central America: A Critical Balance).

    Science.gov (United States)

    Amadio, Massimo, Comp.; And Others

    Global society is polarized between the modern capitalist sector and the marginal sector, which is composed of indigenous, poor, and ethnic, tribal people. The problems of education for groups in Latin America, key issues in planning to meet their needs, and strategies to resolve them, are the focus of this publication. Nine papers provide a…

  12. Central Bank autonomy in Europe and Latin America: analysis of differences and applications Autonomía de la banca central en Europa y América Latina

    Directory of Open Access Journals (Sweden)

    Rollinat Robert

    1996-06-01

    Full Text Available This article makes a comparative analysis of the experiences of the independent central bank in Latin America and Europe. After reviewing the problems and theories of central bank autonomy, it studies the recent evolution of the Latin American central bank in comparison with the European central bank, high lights the perverse effects of the reforms, and shows that their objective is more the stability of the financial system than the stability of prices. Finally, it describes the tests to which the new Latin American central banks have been subjected and the effects on their credibility. It concludes that these entities have had to correct and pay for the incoherences and errors of the market, and that their independence or autonomy depends on their continuing to ful fill this role, not only for economíc or monetary reasons but for the needs of political and social democracy.Este artículo hace un análisis comparativo de las experiencias de la banca central independiente en América Latina y Europa. Después de revisar los problemas y las teorías de la autonompia de los bancos centrales, estudia la reciente evolución de la banca central latinoamericana en comparación con la europea, destaca los efectos perversos de estas reformas u muestra que sus objetivo es más la estabilidad del sistema financiero que la de los precios. Finalmente, describe las pruebas a que han sido sometidos los nuevos bancos centrales latinomaericanos y los efectos de sus credibilidad. Concluye que estas entidades han tenido que corregir y pagar las incoherencias y los errrores del mercado, y que su 'independencia' o autonomía depende de que sigan cumpliendo con ese papel no sólo por razones económicas o monetarias sino por las necesidades de la democracia política y social.

  13. Security Assistance to Central America: Assessment of U.S. Involvement in El Salvador, Guatemala, and Honduras.

    Science.gov (United States)

    1986-09-01

    34 encomienda " (7:155) system which divided the land of Latin America among its settlers, to include all the Indians living on the land as the subjects and labor...all subservient to the crown in Spain. Problems with the Indians acceptance of the encomienda system and internal strife prompted a change in 1570...and stagnation. Spanish rule nearly destroyed the Indian race with its encomienda slave system, but forced upon the area its lasting heritage of tongue

  14. The Great American Biotic Interchange in frogs: multiple and early colonization of Central America by the South American genus Pristimantis (Anura: Craugastoridae).

    Science.gov (United States)

    Pinto-Sánchez, Nelsy Rocío; Ibáñez, Roberto; Madriñán, Santiago; Sanjur, Oris I; Bermingham, Eldredge; Crawford, Andrew J

    2012-03-01

    The completion of the land bridge between North and South America approximately 3.5-3.1 million years ago (Ma) initiated a tremendous biogeographic event called the Great American Biotic Interchange (GABI), described principally from the mammalian fossil record. The history of biotic interchange between continents for taxonomic groups with poor fossil records, however, is not well understood. Molecular and fossil data suggest that a number of plant and animal lineages crossed the Isthmus of Panama well before 3.5 Ma, leading biologists to speculate about trans-oceanic dispersal mechanisms. Here we present a molecular phylogenetic analysis of the frog genus Pristimantis based on 189 individuals of 137 species, including 71 individuals of 31 species from Panama and Colombia. DNA sequence data were obtained from three mitochondrial (COI, 12S, 16S) and two nuclear (RAG-1 and Tyr) genes, for a total of 4074 base pairs. The resulting phylogenetic hypothesis showed statistically significant conflict with most recognized taxonomic groups within Pristimantis, supporting only the rubicundus Species Series, and the Pristimantis myersi and Pristimantis pardalis Species Groups as monophyletic. Inference of ancestral areas based on a likelihood model of geographic range evolution via dispersal, local extinction, and cladogenesis (DEC) suggested that the colonization of Central America by South American Pristimantis involved at least 11 independent events. Relaxed-clock analyses of divergence times suggested that at least eight of these invasions into Central America took place prior to 4 Ma, mainly in the Miocene. These findings contribute to a growing list of molecular-based biogeographic studies presenting apparent temporal conflicts with the traditional GABI model. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. The Role of Long-Term Tectonic Deformation on the Distribution of Present-Day Seismic Activity in the Caribbean and Central America

    Science.gov (United States)

    Schobelock, J.; Stamps, D. S.; Pagani, M.; Garcia, J.; Styron, R. H.

    2017-12-01

    The Caribbean and Central America region (CCAR) undergoes the entire spectrum of earthquake types due to its complex tectonic setting comprised of transform zones, young oceanic spreading ridges, and subductions along its eastern and western boundaries. CCAR is, therefore, an ideal setting in which to study the impacts of long-term tectonic deformation on the distribution of present-day seismic activity. In this work, we develop a continuous tectonic strain rate model based on inter-seismic geodetic data and compare it with known active faults and earthquake focal mechanism data. We first create a 0.25o x 0.25o finite element mesh that is comprised of block geometries defined in previously studies. Second, we isolate and remove transient signals from the latest open access community velocity solution from UNAVCO, which includes 339 velocities from COCONet and TLALOCNet GNSS data for the Caribbean and Central America, respectively. In a third step we define zones of deformation and rigidity by creating a buffer around the boundary of each block that varies depending on the size of the block and the expected deformation zone based on locations of GNSS data that are consistent with rigid block motion. We then assign each node within the buffer a 0 for the deforming areas and a plate index outside the buffer for the rigid. Finally, we calculate a tectonic strain rate model for CCAR using the Haines and Holt finite element approach to fit bi-cubic Bessel splines to the the GNSS/GPS data assuming block rotation for zones of rigidity. Our model of the CCAR is consistent with compression along subduction zones, extension across the mid-Pacific Rise, and a combination of compression and extension across the North America - Caribbean plate boundary. The majority of CCAR strain rate magnitudes range from -60 to 60 nanostrains/yr. Modeling results are then used to calculate expected faulting behaviors that we compare with mapped geologic faults and seismic activity.

  16. The idol beneath the altar.

    Science.gov (United States)

    Clemens, Norman A

    2014-03-01

    Drawing on the imagery of a Mayan idol hidden beneath the altar of a Catholic mission church imposed on a Mayan city by Spanish conquerors, the author discusses the role of deeply rooted core beliefs that are not always evident on the surface-and the observation that, in clinical practice, things are not always as they seem. Psychotherapists may unconsciously be seen as invading cultural enemies.

  17. Geomorphic analysis of transient landscapes in the Sierra Madre de Chiapas and Maya Mountains (northern Central America): implications for the North American-Caribbean-Cocos plate boundary

    Science.gov (United States)

    Andreani, L.; Gloaguen, R.

    2016-01-01

    We use a geomorphic approach in order to unravel the recent evolution of the diffuse triple junction between the North American, Caribbean, and Cocos plates in northern Central America. We intend to characterize and understand the complex tectonic setting that produced an intricate pattern of landscapes using tectonic geomorphology, as well as available geological and geophysical data. We classify regions with specific relief characteristics and highlight uplifted relict landscapes in northern Central America. We also analyze the drainage network from the Sierra Madre de Chiapas and Maya Mountains in order to extract information about potential vertical displacements. Our results suggest that most of the landscapes of the Sierra Madre de Chiapas and Maya Mountains are in a transient stage. Topographic profiles and morphometric maps highlight elevated relict surfaces that are characterized by a low-amplitude relief. The river longitudinal profiles display upper reaches witnessing these relict landscapes. Lower reaches adjust to new base-level conditions and are characterized by multiple knickpoints. These results backed by published GPS and seismotectonic data allow us to refine and extend existing geodynamic models of the triple junction. Relict landscapes are delimited by faults and thus result from a tectonic control. The topography of the Sierra Madre de Chiapas evolved as the result of (1) the inland migration of deformation related to the coupling between the Chiapas Massif and the Cocos forearc sliver and (2) the compression along the northern tip of the Central American volcanic arc. Although most of the shortening between the Cocos forearc sliver and the North American Plate is accommodated within the Sierra de Chiapas and Sierra de los Cuchumatanes, a small part may be still transmitted to the Maya Mountains and the Belize margin through a "rigid" Petén Basin.

  18. Intraplate mountain building in response to continent continent collision—the Ancestral Rocky Mountains (North America) and inferences drawn from the Tien Shan (Central Asia)

    Science.gov (United States)

    Dickerson, Patricia Wood

    2003-04-01

    The intraplate Ancestral Rocky Mountains of western North America extend from British Columbia, Canada, to Chihuahua, Mexico, and formed during Early Carboniferous through Early Permian time in response to continent-continent collision of Laurentia with Gondwana—the conjoined masses of Africa and South America, including Yucatán and Florida. Uplifts and flanking basins also formed within the Laurentian Midcontinent. On the Gondwanan continent, well inboard from the marginal fold belts, a counterpart structural array developed during the same period. Intraplate deformation began when full collisional plate coupling had been achieved along the continental margin; the intervening ocean had been closed and subduction had ceased—that is, the distinction between upper versus lower plates became moot. Ancestral Rockies deformation was not accompanied by volcanism. Basement shear zones that formed during Mesoproterozoic rifting of Laurentia were reactivated and exerted significant control on the locations, orientations, and modes of displacement on late Paleozoic faults. Ancestral Rocky Mountain uplifts extend as far south as Chihuahua and west Texas (28° to 33°N, 102° to 109°W) and include the Florida-Moyotes, Placer de Guadalupe-Carrizalillo, Ojinaga-Tascotal and Hueco Mountain blocks, as well as the Diablo and Central Basin Platforms. All are cored with Laurentian Proterozoic crystalline basement rocks and host correlative Paleozoic stratigraphic successions. Pre-late Paleozoic deformational, thermal, and metamorphic histories are similar as well. Southern Ancestral Rocky Mountain structures terminate along a line that trends approximately N 40°E (present coordinates), a common orientation for Mesoproterozoic extensional structures throughout southern to central North America. Continuing Tien Shan intraplate deformation (Central Asia) has created an analogous array of uplifts and basins in response to the collision of India with Eurasia, beginning in late

  19. Genetic characterization and phylogenetic analysis of skunk-associated rabies viruses in North America with special emphasis on the central plains.

    Science.gov (United States)

    Davis, Rolan; Nadin-Davis, Susan A; Moore, Michael; Hanlon, Cathleen

    2013-06-01

    Across North America the skunk acts as a reservoir for several rabies virus variants. Some of these variants are geographically restricted in range as is the case for the California skunk variant and two distinct variants present in Mexico. In contrast the North Central and South Central skunk rabies viruses are dispersed in overlapping ranges over large areas of the Midwestern region of the United States with the former extending into southern parts of the Canadian prairies. Despite this extensive range, there has been only very limited molecular characterization of these two viral variants. This study has examined the genetic diversity of the rabies viruses associated with North American skunks, with particular emphasis on the South Central skunk variant which was found to comprise three distinct geographically restricted groups of viruses that could in some cases be further sub-divided. The phylogenetic relationships of these groups and sub-groups allowed us to infer the likely direction of spread of these variants in some instances. Patterns of amino acid replacement of North American skunk-associated rabies viruses for both the nucleoprotein and glycoprotein products are also examined. These patterns reflect the virus phylogeny but no amino acid residues associated specifically with the skunk host were identified. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Education for Management in Central America. The Role of the Library of the Instituto Centroamericano de Administracion de Empresas

    Science.gov (United States)

    Bloch, Thomas

    1973-01-01

    The institute, established in 1968, is a multinational organization for education in management at the post-graduate level. Its library, with five staff members, now has 4,000 volumes and receives 300 periodical publications: it should eventually become a Central American business and economic management information and research center. (Author/SJ)

  1. The University as Agent of Social Transformation: The Case of the University of Central America in El Salvador

    Science.gov (United States)

    Valiente, Orfilio Ernesto

    2015-01-01

    In 1965, the Jesuit-run Central American University (UCA) was launched in El Salvador as the wealthy family's educational alternative to the increasingly leftist National University. But within a decade, the UCA would shift its focus to the inequalities and injustice experienced by the country's popular majorities and to its own role as society's…

  2. At the foot of the shrew: Manus morphology distinguishes closely-related Cryptotis goodwini and Cryptotis griseoventris (Mammalia: Soricidae) in Central America

    Science.gov (United States)

    Woodman, Neal; Stephens, Ryan B.

    2010-01-01

    Small-eared shrews (Mammalia, Soricidae) of the New World genus Cryptotis are distributed from eastern North America to the northern Andes of South America. One well-defined clade in this genus is the Central American Cryptotis mexicana group, whose members are set off from other species in the genus by their variably broader fore feet and more elongate and broadened fore claws. Two species in the C. mexicana group, Cryptotis goodwini Jackson and Cryptotis griseoventris Jackson, inhabit highlands in Guatemala and southern Mexico and are presumed to be sister species whose primary distinguishing feature is the larger body size of C. goodwini. To better characterize these species and confirm the identification of recently-collected specimens, we obtained digital X-ray images of the manus from large series of dried skins of both species. Measurements of the metacarpals and phalanges successfully separated most specimens of C. goodwini and C. griseoventris. These measurements also show that the fore feet of C. griseoventris from Chiapas, Mexico, are morphologically distinct from those of members of the species inhabiting Guatemala. Univariate, bivariate, and multivariate analyses indicate that fore foot characters are more conservative within species of the C. mexicana group than are cranio-mandibular characters. Patterns of evolution of fore foot characters that superficially appear to be linear gradations are actually more complex, illustrating individual evolutionary trajectories.

  3. First record of the oak gall wasp genus Neuroterus Hartig, 1840 (Hymenoptera, Cynipidae, Cynipini from Central America with description of three new species from Panama and Costa Rica

    Directory of Open Access Journals (Sweden)

    E. Medianero

    2017-05-01

    Full Text Available Three new species of Neuroterus Hartig, 1840 (Hymenoptera: Cynipidae: Cynipini are described from Panama and Costa Rica: Neuroterus elvisi sp. n., Neuroterus pulchrigalla sp. n., and Neuroterus glandiphilus sp. n. The new species are the first of the genus Neuroterus recorded from Central America and the Neotropical region. The new species induce galls on Quercus bumelioides Liebm. (Fagaceae, sect. Quercus, White Oaks. Additional evidence of the presence of other unidentified species of Neuroterus in the sampled area is presented. Diagnostic morphological characters, gall descriptions, distributions, host plant and other biological data of the new species are given and discussed. http://urn:lsid:zoobank.org:pub:48D0C1E1-1D0C-40D8-B890-FFC85AE7A213

  4. Is violence associated with increased risk behavior among MSM? Evidence from a population-based survey conducted across nine cities in Central America

    Directory of Open Access Journals (Sweden)

    Jennifer Wheeler

    2014-10-01

    Full Text Available Background/Objective: There is a dearth of research examining the linkages between violence and HIV risk behavior among men who have sex with men (MSM, including those who identify as transgender women (TW, particularly in Central America where violence is widespread. In this paper, we use population-based survey results to independently examine the correlations between physical, emotional and sexual violence and HIV risk behavior among MSM populations in five countries in Central America. Design: As part of USAID's Combination Prevention for HIV program in Central America, PASMO conducted population based surveys using respondent-driven sampling (RDS in nine cities in Guatemala, El Salvador, Nicaragua, Costa Rica, and Panama. Initial seeds were recruited using the following criteria: individuals who represented subgroups of MSM by self-identification (homosexual vs. heterosexual or bisexual vs. transgender, social economic strata, and by sex work practices. This study examines the association between violence and 1 HIV risk behaviors relevant to the study populations; 2 protective behaviors; and 3 reported STIs. Individualized RDS estimator weights for each outcome variable were calculated using RDSAT software, and logistic regression analysis was used to determine associations between different forms of violence and the outcome variables. Results: MSM who experienced physical violence were more likely to be engaged in transactional sex (OR: 1.76 [1.42–2.18], have multiple partners in the past 30 days (OR: 1.37 [1.09–1.71], and have engaged in sex under the influence of alcohol or drugs (OR: 1.51 [1.24–1.83]. Both physical violence and psychological/verbal violence were also associated with reporting STI symptoms or diagnosis within the past 12 months (OR: 1.72 [1.34–2.21] and 1.80 [1.45–2.23]. The effects of violence on the outcomes were observed after controlling for other risk factors. Transgender women were 3.9 times more likely

  5. Crustal structure beneath Eastern Greenland

    DEFF Research Database (Denmark)

    Reiche, Sönke; Thybo, H.; Kaip, G.

    2011-01-01

    is recorded by 350 Reftek Texan receivers for 10 equidistant shot points along the profile. We use forward ray tracing modelling to construct a two-dimensional velocity model from the observed travel times. These results show the first images of the subsurface velocity structure beneath the Greenland ice......The conjugate Atlantic passive margins of western Norway and eastern Greenland are characterized by the presence of coast-parallel mountain ranges with peak elevations of more than 3.5 km close to Scoresby Sund in Eastern Greenland. Knowledge about crustal thickness and composition below...

  6. Effect of etanercept therapy on psoriasis symptoms in patients from Latin America, Central Europe, and Asia: a subset analysis of the PRISTINE trial.

    Science.gov (United States)

    Kemeny, L; Amaya, M; Cetkovska, P; Rajatanavin, N; Lee, W-R; Szumski, A; Marshall, L; Mahgoub, E Y; Aldinç, E

    2015-05-21

    Psoriasis prevalence and characteristics in Asia, Central Europe, and Latin America have not been thoroughly investigated and there are no large trials for biologic treatments for patients from these regions. The goal of this analysis was to report clinical response to anti-tumor necrosis factor-alpha treatment in these patients. Patients from Argentina, Czech Republic, Hungary, Mexico, Taiwan, and Thailand (N=171) were included in this subset analysis of the PRISTINE trial. Patients with stable moderate-to-severe plaque psoriasis were blinded and randomized to receive etanercept 50 mg once weekly (QW) or biweekly (BIW) for 12 weeks, followed by 12 weeks of open-label QW treatment with etanercept 50 mg through week 24 (QW/QW vs. BIW/QW). Concomitant methotrexate (≤20 mg/week) and mild topical corticosteroids or other agents were permitted at the physician's discretion, in accordance with therapeutic practice. As early as week 8, 26.7 % in the etanercept QW group and 44.0 % in the BIW group achieved Psoriasis Area and Severity Index (PASI) 75. At weeks 12 and 24, respectively, PASI 75 increased to 39.5 % and 62.8 % in the QW/QW group and 66.7 % and 83.3 % in the BIW/QW group. PASI 75 was significantly different between treatment groups from week 8 through the end of study (pAsia, Central Europe, and Latin America. A more rapid response was observed in patients who received BIW treatment for the first 12 weeks which was sustained after reducing to QW dosing for the subsequent 12 weeks. Response rates were similar to those observed in the overall PRISTINE population. ClinicalTrials.gov identifier NCT00663052 .

  7. Structural Vulnerability Among Migrating Women and Children Fleeing Central America and Mexico: The Public Health Impact of “Humanitarian Parole”

    Science.gov (United States)

    Valdez, Elizabeth Salerno; Valdez, Luis A.; Sabo, Samantha

    2015-01-01

    Since October 2013, US Customs and Border Patrol has apprehended 15,979 families on the Southwest Border of the US. Daily, migrating women and children from Mexico and Central America that qualify for humanitarian parole are released from immigration detention to a humanitarian aid organization in Southern Arizona. After several days in detention facilities, these families arrive tired, hungry, dehydrated, and with minimal direction regarding their final destination, and adherence to the parameters of their parole. Project helping hands (PHHs) utilizes a network of volunteers to provide the women and children with food, water, clothing, hygiene products, hospitality, and legal orientation. The aim of this assessment was to document the experiences of families granted humanitarian parole through the lens of structural vulnerability. Here, we apply qualitative methods to elicit PHH lead volunteer perspectives regarding the migration experience of migrating families. Using inductive analysis, we found six major themes emerged from the qualitative data: reasons for leaving, experience on the journey, dehumanization in detention, family separation, vulnerability, and resiliency. These findings elucidate the different physical and psychological distresses that migrating families from Mexico and Central America experience before, during and after their arrival at the US–Mexico border. We posit that these distresses are a result of, or exacerbated by, structural vulnerability. Structural vulnerability has life-long health implications for a sub-population of young mothers and their children. The number of migrating families who have experienced traumatic events before and during their migration experience continues to expand and thus warrants consideration of mental health surveillance and intervention efforts for these families. More public health research is needed to better understand and combat the health challenges of this growing population. PMID:26157791

  8. Magmas with slab fluid and decompression melting signatures coexisting in the Gulf of Fonseca: Evidence from Isla El Tigre volcano (Honduras, Central America)

    Science.gov (United States)

    Mattioli, Michele; Renzulli, Alberto; Agostini, Samuele; Lucidi, Roberto

    2016-01-01

    Isla El Tigre volcano is located in the Gulf of Fonseca (Honduras) along the Central America volcanic front, where a significant change in the strike of the volcanic chain is observed. The studied samples of this poorly investigated volcano are mainly subalkaline basic to intermediate lavas (basalts and basaltic andesites) and subordinate subalkaline/alkaline transitional basalts, both having the typical mineralogical and geochemical characteristics of arc volcanic rocks. On the basis of petrographic and geochemical features, two groups of rocks have been distinguished. Lavas from the main volcanic edifice are highly porphyritic and hy-qz normative, and have lower MgO contents ( 5 wt.%), are ol-hy normative and show lower HFSE depletions relative to LILE and LREE, with lower Ba/La, Ba/Nb and Zr/Nb ratios. This suggests that mantle-derived magmas were not produced by the same process throughout the activity of the volcano. The bulk rock geochemistry and 87Sr/86Sr (0.70373-0.70382), 143Nd/144Nd (0.51298-0.51301), 206Pb/204Pb (18.55-18.58), 207Pb/204Pb (15.54-15.56) and 208Pb/204Pb (38.23-38.26) isotopic data of Isla El Tigre compared with the other volcanoes of the Gulf of Fonseca and all available literature data for Central America suggests that this stratovolcano was mainly built by mantle-derived melts driven by slab-derived fluid-flux melting, while magmas erupted through its parasitic cones have a clear signature of decompression melting with minor slab contribution. The coexistence of these two different mantle melting generation processes is likely related to the complex geodynamic setting of the Gulf of Fonseca, where the volcanic front changes direction by ca. 30° and two fundamental tectonic structures of the Chortis continental block, mainly the N-S Honduras Depression and the NE-SW Guayape Fault Zone, cross each other.

  9. Lithospheric discontinuities beneath the U.S. Midcontinent - signatures of Proterozoic terrane accretion and failed rifting

    Science.gov (United States)

    Chen, Chen; Gilbert, Hersh; Fischer, Karen M.; Andronicos, Christopher L.; Pavlis, Gary L.; Hamburger, Michael W.; Marshak, Stephen; Larson, Timothy; Yang, Xiaotao

    2018-01-01

    Seismic discontinuities between the Moho and the inferred lithosphere-asthenosphere boundary (LAB) are known as mid-lithospheric discontinuities (MLDs) and have been ascribed to a variety of phenomena that are critical to understanding lithospheric growth and evolution. In this study, we used S-to-P converted waves recorded by the USArray Transportable Array and the OIINK (Ozarks-Illinois-Indiana-Kentucky) Flexible Array to investigate lithospheric structure beneath the central U.S. This region, a portion of North America's cratonic platform, provides an opportunity to explore how terrane accretion, cratonization, and subsequent rifting may have influenced lithospheric structure. The 3D common conversion point (CCP) volume produced by stacking back-projected Sp receiver functions reveals a general absence of negative converted phases at the depths of the LAB across much of the central U.S. This observation suggests a gradual velocity decrease between the lithosphere and asthenosphere. Within the lithosphere, the CCP stacks display negative arrivals at depths between 65 km and 125 km. We interpret these as MLDs resulting from the top of a layer of crystallized melts (sill-like igneous intrusions) or otherwise chemically modified lithosphere that is enriched in water and/or hydrous minerals. Chemical modification in this manner would cause a weak layer in the lithosphere that marks the MLDs. The depth and amplitude of negative MLD phases vary significantly both within and between the physiographic provinces of the midcontinent. Double, or overlapping, MLDs can be seen along Precambrian terrane boundaries and appear to result from stacked or imbricated lithospheric blocks. A prominent negative Sp phase can be clearly identified at 80 km depth within the Reelfoot Rift. This arrival aligns with the top of a zone of low shear-wave velocities, which suggests that it marks an unusually shallow seismic LAB for the midcontinent. This boundary would correspond to the top of a

  10. Management training in global health education: a Health Innovation Fellowship training program to bring healthcare to low-income communities in Central America.

    Science.gov (United States)

    Prado, Andrea M; Pearson, Andy A; Bertelsen, Nathan S

    2018-01-01

    Interprofessional education is increasingly recognized as essential for health education worldwide. Although effective management, innovation, and entrepreneurship are necessary to improve health systems, business schools have been underrepresented in global health education. Central America needs more health professionals trained in health management and innovation to respond to health disparities, especially in rural communities. This paper explores the impact of the Health Innovation Fellowship (HIF), a new training program for practicing health professionals offered jointly by the Central American Healthcare Initiative and INCAE Business School, Costa Rica. Launched in 2014, HIF's goal is to create a network of highly trained interdisciplinary health professionals in competencies to improve health of Central American communities through better health management. The program's fellows carried out innovative healthcare projects in their local regions. The first three annual cohorts (total of 43 fellows) represented all health-related professions and sectors (private, public, and civil society) from six Central American countries. All fellows attended four 1-week, on-site modular training sessions, received ongoing mentorship, and stayed connected through formal and informal networks and webinars through which they exchange knowledge and support each other. CAHI stakeholders supported HIF financially. Impact evaluation of the three-year pilot training program is positive: fellows improved their health management skills and more than 50% of the projects found either financial or political support for their implementation. HIF's strengths include that both program leaders and trainees come from the Global South, and that HIF offers a platform to collaborate with partners in the Global North. By focusing on promoting innovation and management at a top business school in the region, HIF constitutes a novel capacity-building effort within global health education. HIF

  11. Convective upwelling in the mantle beneath the Gulf of California.

    Science.gov (United States)

    Wang, Yun; Forsyth, Donald W; Savage, Brian

    2009-11-26

    In the past six million years, Baja California has rifted obliquely apart from North America, opening up the Gulf of California. Between transform faults, seafloor spreading and rifting is well established in several basins. Other than hotspot-dominated Iceland, the Gulf of California is the only part of the world's seafloor-spreading system that has been surrounded by enough seismometers to provide horizontal resolution of upper-mantle structure at a scale of 100 kilometres over a distance great enough to include several spreading segments. Such resolution is needed to address the long-standing debate about the relative importance of dynamic and passive upwelling in the shallow mantle beneath spreading centres. Here we use Rayleigh-wave tomography to image the shear velocity in the upper 200 kilometres or so of the mantle. Low shear velocities similar to those beneath the East Pacific Rise oceanic spreading centre underlie the entire length of the Gulf, but there are three concentrated locations of anomalously low velocities spaced about 250 kilometres apart. These anomalies are 40 to 90 kilometres beneath the surface, at which depths petrological studies indicate that extensive melting of passively upwelling mantle should begin. We interpret these seismic velocity anomalies as indicating that partial melting triggers dynamic upwelling driven by either the buoyancy of retained melt or by the reduced density of depleted mantle.

  12. Western North America dynamics

    Science.gov (United States)

    Ghosh, A.; Becker, T. W.; Humphreys, G.; Gérault, M.

    2009-12-01

    Basal shear tractions, as generated by mantle convection, are likely to affect the stress field over western North America, and hence, influence the deformation of the North American lithosphere. Earlier studies (Humphreys & Coblentz (2007)) have argued for the importance of shear tractions beneath the continent, but at a reduced amplitude from those predicted by Becker & O'Connell (2001). However, these tractions did not take into account the existence of lateral viscosity variations (LVVs) beneath North America, resulting from strong cratonic root and weak plate margin. We evaluate the tractions and the resulting stresses over North America by incorporating LVVs in a global, high resolution, finite element convection code, CitcomS. Since our ultimate goal is to match observables, such as plate motions and geoid, in addition to stresses, we perform a global inversion for both radial and lateral viscosity variations and choose the viscosity structures that yield a good fit simultaneously to both the global geoid and plate motions. We evaluate the tractions and corresponding stress field from those models. We also attempt to incorporate the effects of gravitational potential energy (GPE) in our convection model. The combined stress field from GPE and tractions are compared to stress observations, such as the World Stress Map.

  13. South America Monsoon variability on millennial to multi-centennial time scale during the Holocene in central eastern Brazil

    Science.gov (United States)

    Strikis, N. M.; Cruz, F. W.; Cheng, H.; Karmann, I.; Vuille, M.; Edwards, R.; Wang, X.; Paula, M. S.; Novello, V. F.; Auler, A.

    2011-12-01

    A paleoprecipitation reconstruction based on high resolution and well-dated speleothem oxygen isotope records shows that the monsoon precipitation over central eastern Brazil underwent to strong variations on millennial to multi-centennial time-scales during the Holocene. This new record indicates that abrupt events of increase in monsoon precipitation are correlated to Bond events 6, 5 and 4 and also with 8.2 ky event during the early and mid-Holocene, with a mean amplitude of 1.5 % (PDB). The pacing and structure of such events are general consistent with variations in solar activity suggested by atmospheric Δ14 C records. In the late-Holocene, abrupt events of increase in monsoon precipitation peaking at 3.2, 2.7 and 2.3 ky B.P. are approximately synchronous with periods of low solar minima. In this regard, the most prominent event occurred during the late Holocene occurred at ~2.7 ky B.P. In addition, these positive anomalies of the precipitation recorded in central eastern Brazil are also in good agreement with variations in Titicaca lake level. The good correspondence between the speleothem and marine records imply that the variations in the north Atlantic sea surface temperature is the main forcing for abrupt millennial to multi-centennial precipitations variation within the region under influence of South American Monsoon.

  14. Along-strike Translation of a Fossil Slab Beneath California (Invited)

    Science.gov (United States)

    Forsyth, D. W.

    2013-12-01

    There are three places where subduction ceased before a spreading ridge was consumed at a trench, leaving behind remnant microplates that were incorporated into the non-subducting oceanic plate. In the cases of the Phoenix plate off the Antarctic peninsula and the Guadalupe and Magdalena microplates off Baja California, fossil slabs still attached to the microplates have been traced into the asthenosphere using seismological techniques. Apparently deep subducting plates can tear off from the surface plate leaving behind fossil pieces of young oceanic lithosphere extending 100 km or more into the asthenosphere. The young slab fragments may be close to neutral buoyancy with their asthenospheric surroundings. In the case of the Monterey microplate off central California, now part of the Pacific plate, oceanic crust has been traced beneath the continental margin using active source seismology. Nicholson et al. (1994) suggested that the translation of the Monterey microplate under North America dragged bits of the overriding plate with it, causing the rotation of the Transverse Ranges in southern California. They also suggested that the San Andreas initiated as a low angle fault between the overriding North American plate and the subducted Monterey plate. There is a gap in coastal, post-subduction volcanic activity opposite the microplate, perhaps because a slab window never formed. A steeply dipping seismic anomaly, the Isabella anomaly, also lies opposite the microplate, probably indicating the continuation of the Monterey slab deep into the asthenosphere. Between the Isabella anomaly and the surface remnants of the Monterey microplate lies the aseismic, creeping section of the San Andreas fault, which we speculate may be caused by the migration of fluids from the subducted plate. The Monterey case differs from the Phoenix and Guadalupe cases in that the hypothesized fossil slab lies beneath the North American plate, which is translating relative to the Pacific

  15. Working conditions and health in Central America: a survey of 12,024 workers in six countries.

    Science.gov (United States)

    Benavides, Fernando G; Wesseling, Catharina; Delclos, George L; Felknor, Sarah; Pinilla, Javier; Rodrigo, Fernando

    2014-07-01

    To describe the survey methodology and initial general findings of the first Central American Survey of Working Conditions and Health. A representative sample of 12,024 workers was interviewed at home in Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama. Questionnaire items addressed worker demographics, employment conditions, occupational risk factors and self-perceived health. Overall, self-employment (37%) is the most frequent type of employment, 8% of employees lack a work contract and 74% of the workforce is not covered by social security. These percentages are higher in Guatemala, Honduras and El Salvador, and lower in Costa Rica, Panama and Nicaragua. A third of the workforce works more than 48 h per week, regardless of gender; this is similar across countries. Women and men report frequent or usual exposures to high ambient temperature (16% and 25%, respectively), dangerous tools and machinery (10%, 24%), work on slippery surfaces (10%, 23%), breathing chemicals (12.1%, 18%), handling toxic substances (5%, 12.1%), heavy loads (6%, 20%) and repetitive movements (43%, 49%). Two-thirds of the workforce perceive their health as being good or very good, and slightly more than half reports having good mental health. The survey offers, for the first time, comparable data on the work and health status of workers in the formal and informal economy in the six Spanish-speaking Central American countries, based on representative national samples. This provides a benchmark for future monitoring of employment and working conditions across countries. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  16. GPS-derived coupling estimates for the Central America subduction zone and volcanic arc faults: El Salvador, Honduras and Nicaragua

    Science.gov (United States)

    Correa-Mora, F.; DeMets, C.; Alvarado, D.; Turner, H. L.; Mattioli, G.; Hernandez, D.; Pullinger, C.; Rodriguez, M.; Tenorio, C.

    2009-12-01

    We invert GPS velocities from 32 sites in El Salvador, Honduras and Nicaragua to estimate the rate of long-term forearc motion and distributions of interseismic coupling across the Middle America subduction zone offshore from these countries and faults in the Salvadoran and Nicaraguan volcanic arcs. A 3-D finite element model is used to approximate the geometries of the subduction interface and strike-slip faults in the volcanic arc and determine the elastic response to coupling across these faults. The GPS velocities are best fit by a model in which the forearc moves 14-16 mmyr-1 and has coupling of 85-100 per cent across faults in the volcanic arc, in agreement with the high level of historic and recent earthquake activity in the volcanic arc. Our velocity inversion indicates that coupling across the potentially seismogenic areas of the subduction interface is remarkably weak, averaging no more than 3 per cent of the plate convergence rate and with only two poorly resolved patches where coupling might be higher along the 550-km-long segment we modelled. Our geodetic evidence for weak subduction coupling disagrees with a seismically derived coupling estimate of 60 +/- 10 per cent from a published analysis of earthquake damage back to 1690, but agrees with three other seismologic studies that infer weak subduction coupling from 20th century earthquakes. Most large historical earthquakes offshore from El Salvador and western Nicaragua may therefore have been intraslab normal faulting events similar to the Mw 7.3 1982 and Mw 7.7 2001 earthquakes offshore from El Salvador. Alternatively, the degree of coupling might vary with time. The evidence for weak coupling indirectly supports a recently published hypothesis that much of the Middle American forearc is escaping to the west or northwest away from the Cocos Ridge collision zone in Costa Rica. Such a hypothesis is particularly attractive for El Salvador, where there is little or no convergence obliquity to drive the

  17. Radical, reformist and aborted liberalism: origins of national regimes in Central America Liberalismo radical, reformista y frustrado: orígenes de los regímenes nacionales en América central

    Directory of Open Access Journals (Sweden)

    James MAHONEY

    2011-06-01

    Full Text Available During the twentieth century, the countries of Central America were characterized by remarkably different political regimes: military-authoritarianism in Guatemala and El Salvador, progressive democracy in Costa Rica and traditional-authoritarianism in Honduras and Nicaragua. This article explains these contrasting regime outcomes by exploring the agrarian and state-building reforms pursued by political leaders during the nineteenth– and early twentieth century liberal reform period. Based on differences in the transformation of state and class structures, three types of liberalism are identified: radical liberalism in Guatemala and El Salvador, reformist liberalism in Costa Rica and aborted liberalism in Honduras and Nicaragua. It is argued that these types of liberalism set the Central American countries on contrasting paths of political development, culminating in diverse regime outcomes.Durante el siglo XX, los países de América Central se caracterizaron por tener regímenes políticos muy diferentes: el autoritarismo militar en Guatemala y El Salvador; la democracia progresista en Costa Rica y el autoritarismo tradicional en Honduras y Nicaragua. Este artículo explica los resultados de estos distintos regímenes mediante la exploración de las reformas agrarias y de la construcción del Estado llevadas a cabo por los líderes políticos durante el siglo XIX y principios del periodo de reformas liberales del siglo XX. Basándose en las diferencias de la transformación del Estado y de las estructuras de clases, se pueden identificar tres tipos de liberalismo: liberalismo radical en Guatemala y El Salvador; liberalismo reformista en Costa Rica y liberalismo frustrado en Honduras y Nicaragua. Se argumenta que estos tipos de liberalismo condujeron a los países de América Central a caminos contrarios al desarrollo político, culminando así en regímenes con resultados diversos.

  18. Modelling the Crust beneath the Kashmir valley in Northwestern Himalaya

    Science.gov (United States)

    Mir, R. R.; Parvez, I. A.; Gaur, V. K.; A.; Chandra, R.; Romshoo, S. A.

    2015-12-01

    We investigate the crustal structure beneath five broadband seismic stations in the NW-SE trendingoval shaped Kashmir valley sandwiched between the Zanskar and the Pir Panjal ranges of thenorthwestern Himalaya. Three of these sites were located along the southwestern edge of the valley andthe other two adjoined the southeastern. Receiver Functions (RFs) at these sites were calculated usingthe iterative time domain deconvolution method and jointly inverted with surface wave dispersiondata to estimate the shear wave velocity structure beneath each station. To further test the results ofinversion, we applied forward modelling by dividing the crust beneath each station into 4-6homogeneous, isotropic layers. Moho depths were separately calculated at different piercing pointsfrom the inversion of only a few stacked receiver functions of high quality around each piercing point.These uncertainties were further reduced to ±2 km by trial forward modelling as Moho depths werevaried over a range of ±6 km in steps of 2 km and the synthetic receiver functions matched with theinverted ones. The final values were also found to be close to those independently estimated using theH-K stacks. The Moho depths on the eastern edge of the valley and at piercing points in itssouthwestern half are close to 55 km, but increase to about 58 km on the eastern edge, suggesting thathere, as in the central and Nepal Himalaya, the Indian plate dips northeastwards beneath the Himalaya.We also calculated the Vp/Vs ratio beneath these 5 stations which were found to lie between 1.7 and1.76, yielding a Poisson's ratio of ~0.25 which is characteristic of a felsic composition.

  19. Estimating the reproductive number, total outbreak size, and reporting rates for Zika epidemics in South and Central America

    Directory of Open Access Journals (Sweden)

    Deborah P. Shutt

    2017-12-01

    Full Text Available As South and Central American countries prepare for increased birth defects from Zika virus outbreaks and plan for mitigation strategies to minimize ongoing and future outbreaks, understanding important characteristics of Zika outbreaks and how they vary across regions is a challenging and important problem. We developed a mathematical model for the 2015/2016 Zika virus outbreak dynamics in Colombia, El Salvador, and Suriname. We fit the model to publicly available data provided by the Pan American Health Organization, using Approximate Bayesian Computation to estimate parameter distributions and provide uncertainty quantification. The model indicated that a country-level analysis was not appropriate for Colombia. We then estimated the basic reproduction number to range between 4 and 6 for El Salvador and Suriname with a median of 4.3 and 5.3, respectively. We estimated the reporting rate to be around 16% in El Salvador and 18% in Suriname with estimated total outbreak sizes of 73,395 and 21,647 people, respectively. The uncertainty in parameter estimates highlights a need for research and data collection that will better constrain parameter ranges.

  20. A pollen-based reconstruction of summer temperature in central North America and implications for circulation patterns during medieval times

    Science.gov (United States)

    Wahl, Eugene R.; Diaz, Henry F.; Ohlwein, Christian

    2012-03-01

    We present a reconstruction of mean summer temperature for the northern Midwest of the USA based on lacustrine pollen records from three different lakes in Wisconsin. The results suggest a relatively warm period during the earlier part of the record (~ 1200-1500 CE) followed by a cooler Little Ice Age (~ 1500-1900) and a subsequent warming to modern conditions. The reconstructed modern summer mean temperature is in good agreement with observations, and the decades of the 1930s to 1950s appear to be the warmest such period in the proxy record (through 1974). Analyses of circulation features associated with the warmest summers in the recent climate record suggest a prevalence of continental ridging accompanied by generally dry conditions during these warm summers in the Midwest. Drought reconstruction using the Palmer Drought Severity Index (PDSI) and tree-ring records as predictors also yield relatively dry conditions in medieval times for the central US. As reported in a number of recent studies, possible forcing mechanisms include La Niña-like conditions in the equatorial Pacific and warmer than average waters in the tropical Indo-western Pacific Ocean possibly coupled to a positive mode of the AMO/NAO North Atlantic circulation pattern.

  1. Two new species of the genus Lepidophthalmus (Decapoda, Axiidea, Callianassidae) from coastal Pacific waters of Central America.

    Science.gov (United States)

    Felder, Darryl L; Robles, Rafael

    2015-09-23

    Two new species of intertidal ghost shrimp are described from coastal Central American habitats of the eastern Pacific Ocean, bringing the total known membership of the genus to 18 species. Lepidophthalmus natesi sp. nov. from Colombia and Nicaragua shares with Lepidophthalmus panamensis sp. nov. from Colombia and Panama the lack of extensive ventral pleomere armor, especially in lacking a median ventral sclerite on the second pleomere. The absence of this plate is also a character of the eastern Pacific species L. rafai Felder & Manning, 1998, but the two new species differ from it in telson shape. Ventral armor including this plate is present in Lepidophthalmus bocourti (A. Milne-Edwards, 1870) and L. eiseni Holmes, 1904 which occur sympatrically with L. natesi sp. nov. in eastern Pacific tropical estuaries. As also known for at least L. bocourti, L. natesi sp. nov. invades and densely colonizes penaeid shrimp aquaculture ponds in regional estuarine settings. Individuals of L. panamensis sp. nov. are of smaller body size but also may be densely concentrated, especially in clayey substrates including those adjacent to intertidal rocks. Despite their similarities in the pleon and shape of the telson, the species can be readily separated by dentition of the cheliped fingers, relative length of the minor chela fingers, the second pleopod appendix of mature males, and egg size. The large eggs of L. panamensis sp. nov. suggest extremely abbreviated development. Characteristic coloration is described for both new species.

  2. 300 years of hydrological records and societal responses to droughts and floods on the Pacific coast of Central America

    Directory of Open Access Journals (Sweden)

    A. Guevara-Murua

    2018-02-01

    Full Text Available The management of hydrological extremes and impacts on society is inadequately understood because of the combination of short-term hydrological records, an equally short-term assessment of societal responses and the complex multi-directional relationships between the two over longer timescales. Rainfall seasonality and inter-annual variability on the Pacific coast of Central America is high due to the passage of the Inter Tropical Convergence Zone (ITCZ and the El Niño–Southern Oscillation (ENSO. Here we reconstruct hydrological variability and demonstrate the potential for assessing societal impacts by drawing on documentary sources from the cities of Santiago de Guatemala (now Antigua Guatemala and Guatemala de la Asunción (now Guatemala City over the period from 1640 to 1945. City and municipal council meetings provide a rich source of information dating back to the beginning of Spanish colonisation in the 16th century. We use almost continuous sources from 1640 AD onwards, including > 190 volumes of Actas de Cabildo and Actas Municipales (minutes of meetings of the city and municipal councils held by the Archivo Histórico de la Municipalidad de Antigua Guatemala (AHMAG and the Archivo General de Centro América (AGCA in Guatemala City. For this 305-year period (with the exception of a total of 11 years during which the books were either missing or damaged, information relating to Catholic rogation ceremonies and reports of flooding events and crop shortages were used to classify the annual rainy season (May to October on a five-point scale from very wet to very dry. In total, 12 years of very wet conditions, 25 years of wetter than usual conditions, 34 years of drier conditions and 21 years of very dry conditions were recorded. An extended drier period from the 1640s to the 1740s was identified and two shorter periods (the 1820s and the 1840s were dominated by dry conditions. Wetter conditions dominated the 1760s–1810s and

  3. Genetic and morphological divergence among Cooper's Hawk (Accipiter cooperii) populations breeding in north-central and western North America

    Science.gov (United States)

    Sonsthagen, Sarah A.; Rosenfield, Robert N.; Bielefeldt, John; Murphy, Robert K.; Stewart, Andrew C.; Stout, William C.; Driscoll, Timothy G.; Bozek, Michael A.; Sloss, Brian L.; Talbot, Sandra L.

    2012-01-01

    Cooper's Hawk (Accipiter cooperii) populations breeding in the northern portion of the species' range exhibit variation in morphological traits that conforms to predictions based on differences in prey size, tree stand density, and migratory behavior. We examined genetic structure and gene flow and compared divergence at morphological traits (PST) and genetic markers (FST) to elucidate mechanisms (selection or genetic drift) that promote morphological diversification among Cooper's Hawk populations. Cooper's Hawks appear to conform to the genetic pattern of an east-west divide. Populations in British Columbia are genetically differentiated from north-central populations (Wisconsin, Minnesota, and North Dakota; pairwise microsatellite FST= 0.031-0.050; mitochondrial DNA ΦST = 0.177-0.204), which suggests that Cooper's Hawks were restricted to at least two Pleistocene glacial refugia. The strength of the Rocky Mountains—Great Plains area as a barrier to dispersal is further supported by restricted gene-flow rates between British Columbia and other sampled breeding populations. Divergence in morphological traits (PST) was also observed across study areas, but with British Columbia and North Dakota differentiated from Wisconsin and Minnesota, a pattern not predicted on the basis of FST and ΦST interpopulation estimates. Comparison of PSTand FSTestimates suggests that heterogeneous selection may be acting on Cooper's Hawks in the northern portion of their distribution, which is consistent with hypotheses that variation in prey mass and migratory behavior among populations may be influencing overall body size and wing chord. We were unable to distinguish between the effects of genetic drift and selection on tail length in the study populations.

  4. Evidence and future scenarios of a low-carbon energy transition in Central America: a case study in Nicaragua

    Science.gov (United States)

    Barido, Diego Ponce de Leon; Johnston, Josiah; Moncada, Maria V.; Callaway, Duncan; Kammen, Daniel M.

    2015-10-01

    The global carbon emissions budget over the next decades depends critically on the choices made by fast-growing emerging economies. Few studies exist, however, that develop country-specific energy system integration insights that can inform emerging economies in this decision-making process. High spatial- and temporal-resolution power system planning is central to evaluating decarbonization scenarios, but obtaining the required data and models can be cost prohibitive, especially for researchers in low, lower-middle income economies. Here, we use Nicaragua as a case study to highlight the importance of high-resolution open access data and modeling platforms to evaluate fuel-switching strategies and their resulting cost of power under realistic technology, policy, and cost scenarios (2014-2030). Our results suggest that Nicaragua could cost-effectively achieve a low-carbon grid (≥80%, based on non-large hydro renewable energy generation) by 2030 while also pursuing multiple development objectives. Regional cooperation (balancing) enables the highest wind and solar generation (18% and 3% by 2030, respectively), at the least cost (US127 MWh-1). Potentially risky resources (geothermal and hydropower) raise system costs but do not significantly hinder decarbonization. Oil price sensitivity scenarios suggest renewable energy to be a more cost-effective long-term investment than fuel oil, even under the assumption of prevailing cheap oil prices. Nicaragua’s options illustrate the opportunities and challenges of power system decarbonization for emerging economies, and the key role that open access data and modeling platforms can play in helping develop low-carbon transition pathways.

  5. Rapid climate change and no-analog vegetation in lowland Central America during the last 86,000 years

    Science.gov (United States)

    Correa-Metrio, Alexander; Bush, Mark B.; Cabrera, Kenneth R.; Sully, Shannon; Brenner, Mark; Hodell, David A.; Escobar, Jaime; Guilderson, Tom

    2012-03-01

    Glacial-interglacial climate cycles are known to have triggered migrations and reassortments of tropical biota. Although long-term precessionally-driven changes in temperature and precipitation have been demonstrated using tropical sediment records, responses to abrupt climate changes, e.g. the cooling of Heinrich stadials or warmings of the deglaciation, are poorly documented. The best predictions of future forest responses to ongoing warming will rely on evaluating the influences of both abrupt and long-term climate changes on past ecosystems. A sedimentary sequence recovered from Lake Petén-Itzá, Guatemalan lowlands, provided a natural archive of environmental history. Pollen and charcoal analyses were used to reconstruct the vegetation and climate history of the area during the last 86,000 years. We found that vegetation composition and air temperature were strongly influenced by millennial-scale changes in the North Atlantic Ocean. Whereas Greenland warm interstadials were associated with warm and relatively wet conditions in the Central American lowlands, cold Greenland stadials, especially those associated with Heinrich events, caused extremely dry and cold conditions. Even though the vegetation seemed to have been highly resilient, plant associations without modern analogs emerged mostly following sharp climate pulses of either warmth or cold, and were paralleled by exceptionally high rates of ecological change. Although pulses of temperature change are evident in this 86,000-year record none matched the rates projected for the 21st Century. According to our findings, the ongoing rapid warming will cause no-modern-analog communities, which given the improbability of returning to lower-than-modern CO2 levels, anthropogenic barriers to migration, and increased anthropogenic fires, will pose immense threats to the biodiversity of the region.

  6. Soil bioengineering measures for disaster mitigation and environmental restoration in Central America: authochtonal cuttings suitability and economic efficiency

    Science.gov (United States)

    Petrone, A.; Preti, F.

    2009-04-01

    The use of Soil Bio-Engineering techniques in Developing countries is a relevant issue for Disaster mitigation, environmental restoration and poverty reduction. Research on authochtonal plants suitable for this kind of works and on economic efficiency is essential for the divulgation of this Discipline. The present paper is focused on this two issues related to the realization of various typologies of Soil Bio-engineering works in the Humid tropic of Nicaragua. In the area of Río Blanco, located in the Department of Matagalpa, Soil bio-engineering installations were built in several sites. The particular structures built were: drainages with live fascine mattress, a live palisade, a vegetated live crib wall for riverbank protection, a vegetative covering made of a metallic net and biotextile coupled with a live palisade made of bamboo. In order to evaluate the suitability of the various plants used in the works, monitorings were performed, one in the live palisade alongside an unpaved road and the other on the live crib wall along a riverbank, collecting survival rate and morphological parameters data. Concerning the economic efficiency we proceed to a financial analysis of the works and once the unit price was obtained, we converted the amount in EPP Dollars (Equal Purchasing Power) in order to compare the Nicaraguan context with the Italian one. Among the used species we found that Madero negro (Gliricidia sepium) and Roble macuelizo (Tabebuia rosea) are adequate for Soil-bioengineering measure on slopes while Helequeme (Erythrina fusca) reported a successful behaviour only in the crib wall for riverbank protection. In the comparison of the costs in Nicaragua and in Italy, the unit price reduction for the central American country ranges between 1.5 times (for the vegetative covering) and almost 4 times (for the fascine mattress) if it's used the EPP dollar exchange rate. Thus, a conclusion can be reached with regard to hydrological-risk mitigating actions

  7. Providers' perspectives on inbound medical tourism in Central America and the Caribbean: factors driving and inhibiting sector development and their health equity implications.

    Science.gov (United States)

    Johnston, Rory; Crooks, Valorie A; Cerón, Alejandro; Labonté, Ronald; Snyder, Jeremy; Núñez, Emanuel O; Flores, Walter G

    2016-01-01

    Many governments and health care providers worldwide are enthusiastic to develop medical tourism as a service export. Despite the popularity of this policy uptake, there is relatively little known about the specific local factors prospectively motivating and informing development of this sector. To identify common social, economic, and health system factors shaping the development of medical tourism in three Central American and Caribbean countries and their health equity implications. In-depth, semi-structured interviews were conducted in Mexico, Guatemala, and Barbados with 150 health system stakeholders. Participants were recruited from private and public sectors working in various fields: trade and economic development, health services delivery, training and administration, and civil society. Transcribed interviews were coded using qualitative data management software, and thematic analysis was used to identify cross-cutting issues regarding the drivers and inhibitors of medical tourism development. Four common drivers of medical tourism development were identified: 1) unused capacity in existing private hospitals, 2) international portability of health insurance, vis-a-vis international hospital accreditation, 3) internationally trained physicians as both marketable assets and industry entrepreneurs, and 4) promotion of medical tourism by public export development corporations. Three common inhibitors for the development of the sector were also identified: 1) the high expense of market entry, 2) poor sector-wide planning, and 3) structural socio-economic issues such as insecurity or relatively high business costs and financial risks. There are shared factors shaping the development of medical tourism in Central America and the Caribbean that help explain why it is being pursued by many hospitals and governments in the region. Development of the sector is primarily being driven by public investment promotion agencies and the private health sector seeking

  8. Providers’ perspectives on inbound medical tourism in Central America and the Caribbean: factors driving and inhibiting sector development and their health equity implications

    Science.gov (United States)

    Johnston, Rory; Crooks, Valorie A.; Cerón, Alejandro; Labonté, Ronald; Snyder, Jeremy; Núñez, Emanuel O.; Flores, Walter G.

    2016-01-01

    Background Many governments and health care providers worldwide are enthusiastic to develop medical tourism as a service export. Despite the popularity of this policy uptake, there is relatively little known about the specific local factors prospectively motivating and informing development of this sector. Objective To identify common social, economic, and health system factors shaping the development of medical tourism in three Central American and Caribbean countries and their health equity implications. Design In-depth, semi-structured interviews were conducted in Mexico, Guatemala, and Barbados with 150 health system stakeholders. Participants were recruited from private and public sectors working in various fields: trade and economic development, health services delivery, training and administration, and civil society. Transcribed interviews were coded using qualitative data management software, and thematic analysis was used to identify cross-cutting issues regarding the drivers and inhibitors of medical tourism development. Results Four common drivers of medical tourism development were identified: 1) unused capacity in existing private hospitals, 2) international portability of health insurance, vis-a-vis international hospital accreditation, 3) internationally trained physicians as both marketable assets and industry entrepreneurs, and 4) promotion of medical tourism by public export development corporations. Three common inhibitors for the development of the sector were also identified: 1) the high expense of market entry, 2) poor sector-wide planning, and 3) structural socio-economic issues such as insecurity or relatively high business costs and financial risks. Conclusion There are shared factors shaping the development of medical tourism in Central America and the Caribbean that help explain why it is being pursued by many hospitals and governments in the region. Development of the sector is primarily being driven by public investment promotion

  9. Phylogeography and Genetic Variation of Triatoma dimidiata, the Main Chagas Disease Vector in Central America, and Its Position within the Genus Triatoma

    Science.gov (United States)

    Bargues, María Dolores; Klisiowicz, Debora R.; Gonzalez-Candelas, Fernando; Ramsey, Janine M.; Monroy, Carlota; Ponce, Carlos; Salazar-Schettino, Paz María; Panzera, Francisco; Abad-Franch, Fernando; Sousa, Octavio E.; Schofield, Christopher J.; Dujardin, Jean Pierre; Guhl, Felipe; Mas-Coma, Santiago

    2008-01-01

    Background Among Chagas disease triatomine vectors, the largest genus, Triatoma, includes species of high public health interest. Triatoma dimidiata, the main vector throughout Central America and up to Ecuador, presents extensive phenotypic, genotypic, and behavioral diversity in sylvatic, peridomestic and domestic habitats, and non-domiciliated populations acting as reinfestation sources. DNA sequence analyses, phylogenetic reconstruction methods, and genetic variation approaches are combined to investigate the haplotype profiling, genetic polymorphism, phylogeography, and evolutionary trends of T. dimidiata and its closest relatives within Triatoma. This is the largest interpopulational analysis performed on a triatomine species so far. Methodology and Findings Triatomines from Mexico, Guatemala, Honduras, Nicaragua, Panama, Cuba, Colombia, Ecuador, and Brazil were used. Triatoma dimidiata populations follow different evolutionary divergences in which geographical isolation appears to have had an important influence. A southern Mexican–northern Guatemalan ancestral form gave rise to two main clades. One clade remained confined to the Yucatan peninsula and northern parts of Chiapas State, Guatemala, and Honduras, with extant descendants deserving specific status. Within the second clade, extant subspecies diversity was shaped by adaptive radiation derived from Guatemalan ancestral populations. Central American populations correspond to subspecies T. d. dimidiata. A southern spread into Panama and Colombia gave the T. d. capitata forms, and a northwestern spread rising from Guatemala into Mexico gave the T. d. maculipennis forms. Triatoma hegneri appears as a subspecific insular form. Conclusions The comparison with very numerous Triatoma species allows us to reach highly supported conclusions not only about T. dimidiata, but also on different, important Triatoma species groupings and their evolution. The very large intraspecific genetic variability found in T

  10. Phylogeography and genetic variation of Triatoma dimidiata, the main Chagas disease vector in Central America, and its position within the genus Triatoma.

    Directory of Open Access Journals (Sweden)

    María Dolores Bargues

    2008-05-01

    Full Text Available Among Chagas disease triatomine vectors, the largest genus, Triatoma, includes species of high public health interest. Triatoma dimidiata, the main vector throughout Central America and up to Ecuador, presents extensive phenotypic, genotypic, and behavioral diversity in sylvatic, peridomestic and domestic habitats, and non-domiciliated populations acting as reinfestation sources. DNA sequence analyses, phylogenetic reconstruction methods, and genetic variation approaches are combined to investigate the haplotype profiling, genetic polymorphism, phylogeography, and evolutionary trends of T. dimidiata and its closest relatives within Triatoma. This is the largest interpopulational analysis performed on a triatomine species so far.Triatomines from Mexico, Guatemala, Honduras, Nicaragua, Panama, Cuba, Colombia, Ecuador, and Brazil were used. Triatoma dimidiata populations follow different evolutionary divergences in which geographical isolation appears to have had an important influence. A southern Mexican-northern Guatemalan ancestral form gave rise to two main clades. One clade remained confined to the Yucatan peninsula and northern parts of Chiapas State, Guatemala, and Honduras, with extant descendants deserving specific status. Within the second clade, extant subspecies diversity was shaped by adaptive radiation derived from Guatemalan ancestral populations. Central American populations correspond to subspecies T. d. dimidiata. A southern spread into Panama and Colombia gave the T. d. capitata forms, and a northwestern spread rising from Guatemala into Mexico gave the T. d. maculipennis forms. Triatoma hegneri appears as a subspecific insular form.The comparison with very numerous Triatoma species allows us to reach highly supported conclusions not only about T. dimidiata, but also on different, important Triatoma species groupings and their evolution. The very large intraspecific genetic variability found in T. dimidiata sensu lato has never

  11. Providers’ perspectives on inbound medical tourism in Central America and the Caribbean: factors driving and inhibiting sector development and their health equity implications

    Directory of Open Access Journals (Sweden)

    Rory Johnston

    2016-11-01

    Full Text Available Background: Many governments and health care providers worldwide are enthusiastic to develop medical tourism as a service export. Despite the popularity of this policy uptake, there is relatively little known about the specific local factors prospectively motivating and informing development of this sector. Objective: To identify common social, economic, and health system factors shaping the development of medical tourism in three Central American and Caribbean countries and their health equity implications. Design: In-depth, semi-structured interviews were conducted in Mexico, Guatemala, and Barbados with 150 health system stakeholders. Participants were recruited from private and public sectors working in various fields: trade and economic development, health services delivery, training and administration, and civil society. Transcribed interviews were coded using qualitative data management software, and thematic analysis was used to identify cross-cutting issues regarding the drivers and inhibitors of medical tourism development. Results: Four common drivers of medical tourism development were identified: 1 unused capacity in existing private hospitals, 2 international portability of health insurance, vis-a-vis international hospital accreditation, 3 internationally trained physicians as both marketable assets and industry entrepreneurs, and 4 promotion of medical tourism by public export development corporations. Three common inhibitors for the development of the sector were also identified: 1 the high expense of market entry, 2 poor sector-wide planning, and 3 structural socio-economic issues such as insecurity or relatively high business costs and financial risks. Conclusion: There are shared factors shaping the development of medical tourism in Central America and the Caribbean that help explain why it is being pursued by many hospitals and governments in the region. Development of the sector is primarily being driven by public

  12. Public purchasers contracting external primary care providers in Central America for better responsiveness, efficiency of health care and public governance: issues and challenges.

    Science.gov (United States)

    Macq, Jean; Martiny, Patrick; Villalobos, Luis Bernardo; Solis, Alejandro; Miranda, Jose; Mendez, Hilda Cecilia; Collins, Charles

    2008-09-01

    Several national health systems in Latin America initiated health reforms to counter widespread criticisms of low equity and efficiency. For public purchasing agencies, these reforms often consisted in contracting external providers for primary care provision. This paper intends to clarify both the complex and intertwined issues characterizing such contracting as well as health system performances within the context of four Central American countries. It results from a European Commission financed project lead between 2002 and 2005, involving participants from Costa Rica, Guatemala, Nicaragua, Salvador, United Kingdom, Netherlands and Belgium, whose aim was to promote exchanges between these participants. The findings presented in this paper are the results of a two stage process: (a) the design of an initial analytical framework, built upon findings from the literature, interlinking characteristics of contractual relation with health systems performances criteria and (b) the use of that framework in four case studies to identify cross-cutting issues. This paper reinforces two pivotal findings: (a) contracting requires not only technical, but also political choices and (b) it cannot be considered as a mechanical process. The unpredictability of its evolution requires a flexible and reactive approach. This should be better assimilated by national and international organizations involved in health services provision, so as to progressively come out of dogmatic approaches in deciding to initiate contractual relation with external providers for primary care provision.

  13. Transboundary aquifers: the response of international law and legal voids in Central America; Acuiferos transfronterizos: respuestas desde el derecho internacional y vacios en Centroamerica

    Energy Technology Data Exchange (ETDEWEB)

    Boeglin, N.

    2012-11-01

    Central America is one of the regions of the world that will suffer the impact of climate change much more than others. The adoption of clear rules on the use of transboundary aquifers and on the need to preserve these groundwater reservoirs from serious pollution by the various states in the region is absolutely essential. Despite the lack of any bilateral or regional frameworks to rule on this issue, many general regulations have been adopted within the international framework of the United Nations that are applicable to shared surface and groundwater resources as well as to transboundary aquifers. The case of the Las Crucitas project in Costa Rica, halted by domestic tribunals thanks to the decisive action of its civilian society, reflects a clear lack of technical information concerning aquifers in Costa Rica, and probably in many other states in the region, despite the very valuable efforts being undertaken by the OAS and UNESCO under the aegis of the ISARM project for the Latin American region.

  14. Noninvasive individual and species identification of jaguars (Panthera onca), pumas (Puma concolor) and ocelots (Leopardus pardalis) in Belize, Central America using cross-species microsatellites and faecal DNA.

    Science.gov (United States)

    Wultsch, Claudia; Waits, Lisette P; Kelly, Marcella J

    2014-11-01

    There is a great need to develop efficient, noninvasive genetic sampling methods to study wild populations of multiple, co-occurring, threatened felids. This is especially important for molecular scatology studies occurring in challenging tropical environments where DNA degrades quickly and the quality of faecal samples varies greatly. We optimized 14 polymorphic microsatellite loci for jaguars (Panthera onca), pumas (Puma concolor) and ocelots (Leopardus pardalis) and assessed their utility for cross-species amplification. Additionally, we tested their reliability for species and individual identification using DNA from faeces of wild felids detected by a scat detector dog across Belize in Central America. All microsatellite loci were successfully amplified in the three target species, were polymorphic with average expected heterozygosities of HE = 0.60 ± 0.18 (SD) for jaguars, HE = 0.65 ± 0.21 (SD) for pumas and HE = 0.70 ± 0.13 (SD) for ocelots and had an overall PCR amplification success of 61%. We used this nuclear DNA primer set to successfully identify species and individuals from 49% of 1053 field-collected scat samples. This set of optimized microsatellite multiplexes represents a powerful tool for future efforts to conduct noninvasive studies on multiple, wild Neotropical felids. © 2014 John Wiley & Sons Ltd.

  15. Technologies to better serve the millions of diabetic patients: a holistic, interactive and persuasive ICT model to facilitate self care, in extremely poor rural zones of Central America.

    Science.gov (United States)

    Vargas-Lombardo, Miguel; Jipsion, Armando; Vejarano, Rafael; Camargo, Ismael; Alvarez, Humberto; Mora, Elena Villalba; Ruíz, Ernestina Menasalva

    2012-04-01

    Health indicators express remarkable gaps between health systems at a world-wide level. Countries of the entire world are overflowed by the need of new strategies, methodologies and technologies to better serve the millions of patients, who demand better medical attention. The present archaic and ephemerally systematized systems widen the gap even more than the quality of medical services that should be provided for the millions of diabetic patients. It is therefore necessary to develop highly familiar environments with diabetic patients and their care needs. A Holistic, Interactive and Persuasive ICT model to facilitate self care of patients with diabetes (hIPAPD), is proposed as an innovative technological development in Panama to health optimized treatment for diabetic patients. Three health centers located in the District of Aguadulce, Province of Cocle, located on Panama's Pacific Coast, were selected to validate the model; the area presents extremely poor population, mostly with one daily meal, without any health insurance and with a high illiteracy rate. A series of experiences in the application and validation process are presented and analyzed in order to confirm the application, value and contribution of ICTs in health care in poor regions of Central America.

  16. Transient slab flattening beneath Colombia

    Science.gov (United States)

    Wagner, L. S.; Jaramillo, J. S.; Ramírez-Hoyos, L. F.; Monsalve, G.; Cardona, A.; Becker, T. W.

    2017-07-01

    Subduction of the Nazca and Caribbean Plates beneath northwestern Colombia is seen in two distinct Wadati Benioff Zones, one associated with a flat slab to the north and one associated with normal subduction south of 5.5°N. The normal subduction region is characterized by an active arc, whereas the flat slab region has no known Holocene volcanism. We analyze volcanic patterns over the past 14 Ma to show that in the mid-Miocene a continuous arc extended up to 7°N, indicating normal subduction of the Nazca Plate all along Colombia's Pacific margin. However, by 6 Ma, we find a complete cessation of this arc north of 3°N, indicating the presence of a far more laterally extensive flat slab than at present. Volcanism did not resume between 3°N and 6°N until after 4 Ma, consistent with lateral tearing and resteepening of the southern portion of the Colombian flat slab at that time.

  17. Life beneath the surface of the central Texan Balcones Escarpment: genus Anillinus Casey, 1918 (Coleoptera, Carabidae, Bembidiini: new species, a key to the Texas species, and notes about their way of life and evolution

    Directory of Open Access Journals (Sweden)

    Igor Sokolov

    2014-06-01

    Full Text Available The Texas fauna of the genus Anillinus Casey, 1918 includes three previously described species (A. affabilis (Brues, 1902, A. depressus (Jeannel, 1963 and A. sinuatus (Jeannel, 1963 and four new species here described: A. acutipennis Sokolov & Reddell sp. n. (type locality: Fort Hood area, Bell County, Texas; A. comalensis Sokolov & Kavanaugh sp. n. (type locality: 7 miles W of New Braunfels, Comal County, Texas; A. forthoodensis Sokolov & Reddell sp. n. (type locality: Fort Hood area, Bell County, Texas; A. wisemanensis Sokolov & Kavanaugh sp. n. (type locality: Wiseman Sink, Hays County, Texas. A key for identification of adults of these species is provided. The fauna includes both soil- and cave-inhabiting species restricted to the Balcones Fault Zone and Lampasas Cut Plain and adjacent areas underlain by the Edwards-Trinity Aquifer. Based on morphological and distributional data, we hypothesize that four lineages of endogean Anillinus species extended their geographical ranges from a source area in the Ouachita-Ozark Mountains to the Balconian region in central Texas. There the cavernous Edwards-Trinity aquifer system provided an excellent refugium as the regional climate in the late Tertiary and early Quaternary became increasingly drier, rendering life at the surface nearly impossible for small, litter-inhabiting arthropods. Isolated within the Edwards-Trinity aquifer system, these anilline lineages subsequently differentiated, accounting for the currently known diversity. The paucity of specimens and difficulty in collecting them suggest that additional undiscovered species remain to be found in the region.

  18. Durability of Efavirenz Compared With Boosted Protease Inhibitor-Based Regimens in Antiretroviral-Naïve Patients in the Caribbean and Central and South America

    Science.gov (United States)

    Caro-Vega, Yanink; Belaunzarán-Zamudio, Pablo F; Crabtree-Ramírez, Brenda E; Shepherd, Bryan E; Grinsztejn, Beatriz; Wolff, Marcelo; Pape, Jean W; Padgett, Denis; Gotuzzo, Eduardo; McGowan, Catherine C; Sierra-Madero, Juan G

    2018-01-01

    Abstract Background Efavirenz (EFV) and boosted protease inhibitors (bPIs) are still the preferred options for firstline antiretroviral regimens (firstline ART) in Latin America and have comparable short-term efficacy. We assessed the long-term durability and outcomes of patients receiving EFV or bPIs as firstline ART in the Caribbean, Central and South America network for HIV epidemiology (CCASAnet). Methods We included ART-naïve, HIV-positive adults on EFV or bPIs as firstline ART in CCASAnet between 2000 and 2016. We investigated the time from starting until ending firstline ART according to changes of third component for any reason, including toxicity and treatment failure, death, and/or loss to follow-up. Use of a third-line regimen was a secondary outcome. Kaplan-Meier estimators of composite end points were generated. Crude cumulative incidence of events and adjusted hazard ratios (aHRs) were estimated accounting for competing risk events. Results We included 14 519 patients: 12 898 (89%) started EFV and 1621 (11%) bPIs. The adjusted median years on firstline ART were 4.6 (95% confidence interval [CI], 4.4–4.7) on EFV and 3.8 (95% CI, 3.8–4.0) on bPI (P < .001). Cumulative incidence of firstline ART ending at 10 years of follow-up was 32% (95% CI, 31–33) on EFV and 44% (95% CI, 39–48) on bPI (aHR, 0.88; 95% CI, 0.78–0.97). The cumulative incidence rates of third-line initiation in the bPI-based group were 6% (95% CI, 2.4–9.6) and 2% (95% CI, 1.4–2.2) among the EFV-based group (P < .01). Conclusions Durability of firstline ART was longer with EFV than with bPIs. EFV-based regimens may continue to be the preferred firstline regimen for our region in the near future due to their high efficacy, relatively low toxicity (especially at lower doses), existence of generic formulations, and affordability for national programs. PMID:29527539

  19. Validation of a Rapid and Reliable Test for Diagnosis of Chagas' Disease by Detection of Trypanosoma cruzi-Specific Antibodies in Blood of Donors and Patients in Central America

    Science.gov (United States)

    Ponce, Carlos; Ponce, Elisa; Vinelli, Elizabeth; Montoya, Alberto; de Aguilar, Vilma; Gonzalez, Antonio; Zingales, Bianca; Rangel-Aldao, Rafael; Levin, Mariano J.; Esfandiari, Javan; Umezawa, Eufrosina S.; Luquetti, Alejandro O.; da Silveira, José Franco

    2005-01-01

    In this study we compared the performance of the Chagas Stat-Pak rapid immunochromatographic test with a standard enzyme-linked immunosorbent assay (ELISA) in the serodiagnosis of Chagas' disease in Central America. Out of 3,400 blood donor samples, 156 (4.6%) were positive in both assays. Three sera out of 2,084 samples from reference laboratories were negative with the rapid test but positive with the ELISA (99.8% agreement). Agreement of 100% between the two tests was observed with 339 additional sera from patients with cardiopathies and 175 sera from potential blood donors in emergency surgical cases occurring on weekends or at night. In conclusion, Chagas Stat-Pak showed 99.6% and 99.9% sensitivity and specificity, respectively, when assayed with 5,998 serum samples. It is a sensitive and specific alternative to the ELISA, as required in medical emergencies and blood screenings in Central America. PMID:16207963

  20. Clinical and virologic outcomes after changes in first antiretroviral regimen at 7 sites in the Caribbean, Central and South America Network (CCASAnet)

    Science.gov (United States)

    Wolff, Marcelo; Shepherd, Bryan E.; Cortés, Claudia; Rebeiro, Peter; Cesar, Carina; Cardoso, Sandra Wagner; Pape, Jean W.; Padgett, Denis; Sierra-Madero, Juan; Echevarria, Juan; McGowan, Catherine C.

    2015-01-01

    Background HIV-infected persons in lower income countries may experience high rates of antiretroviral therapy (ART) change, particularly due to toxicity or other non-failure reasons. Few reports address patient outcomes after these modifications. Methods HIV-infected adults from 7 Caribbean, Central and South America network (CCASAnet) clinical cohorts who modified > or = 1 drug from first ART regimen (ART-1) for any reason thereby starting a second regimen (ART-2) were included. Results 5,565 ART-naïve HAART initiators started ART-2 after a median of 9.8 months on ART-1; 39% changed to ART-2 due to toxicity and 11% due to failure. Median follow-up after starting ART-2 was 2.9 years; 45% subsequently modified ART-2. Cumulative incidences of death at 1, 3, and 5 years after starting ART-2 were 5.1%, 8.4% and 10.5%, respectively. In adjusted analyses, death was associated with older age, clinical AIDS, lower CD4 at ART-2 start, earlier calendar year, and starting ART-2 because of toxicity (adjusted hazard ratio[aHR]=1.5 vs. failure, 95% confidence interval[CI]=1.0–2.1). Cumulative incidences of VF after 1, 3, and 5 years were 9%, 19%, and 25%. In adjusted analyses, VF was associated with younger age, earlier calendar year, lower CD4 at start of ART-2, and starting ART-2 because of failure (aHR=2.1 vs. toxicity, 95% CI=1.5–2.8). Conclusions Among patients modifying first ART regimen, risks of subsequent modifications, mortality, and virologic failure were high. Access to improved antiretrovirals in the region is needed to improve initial treatment success. PMID:26761273

  1. Confirmed clinical case of chronic kidney disease of nontraditional causes in agricultural communities in Central America: a case definition for surveillance

    Directory of Open Access Journals (Sweden)

    Alejandro Ferreiro

    Full Text Available ABSTRACT Over the last 20 years, many reports have described an excess of cases of chronic kidney disease (CKD in the Pacific coastal area of Central America, mainly affecting male farmworkers and signaling a serious public health problem. Most of these cases are not associated with traditional risk factors for CKD, such as aging, diabetes mellitus, and hypertension. This CKD of nontraditional causes (CKDnT might be linked to environmental and/or occupational exposure or working conditions, limited access to health services, and poverty. In response to a resolution approved by the Directing Council of the Pan American Health Organization (PAHO in 2013, PAHO, the U.S. Centers for Disease Control and Prevention, and the Latin American Society of Nephrology and Hypertension (SLANH organized a consultation process in order to expand knowledge on the epidemic of CKDnT and to develop appropriate surveillance instruments. The Clinical Working Group from SLANH was put in charge of finding a consensus definition of a confirmed clinical case of CKDnT. The resulting definition establishes mandatory criteria and exclusion criteria necessary for classifying a case of CKDnT. The definition includes a combination of universally accepted definitions of CKD and the main clinical manifestations of CKDnT. Based on the best available evidence, the Clinical Working Group also formulated general recommendations about clinical management that apply to any patient with CKDnT. Adhering to the definition of a confirmed clinical case of CKDnT and implementing it appropriately is expected to be a powerful instrument for understanding the prevalence of the epidemic, evaluating the results of interventions, and promoting appropriate advocacy and planning efforts.

  2. Confirmed clinical case of chronic kidney disease of nontraditional causes in agricultural communities in Central America: a case definition for surveillance.

    Science.gov (United States)

    Ferreiro, Alejandro; Álvarez-Estévez, Guillermo; Cerdas-Calderón, Manuel; Cruz-Trujillo, Zulma; Mena, Elio; Reyes, Marina; Sandoval-Diaz, Mabel; Sánchez-Polo, Vicente; Valdés, Régulo; Ordúnez, Pedro

    2016-11-01

    Over the last 20 years, many reports have described an excess of cases of chronic kidney disease (CKD) in the Pacific coastal area of Central America, mainly affecting male farmworkers and signaling a serious public health problem. Most of these cases are not associated with traditional risk factors for CKD, such as aging, diabetes mellitus, and hypertension. This CKD of nontraditional causes (CKDnT) might be linked to environmental and/or occupational exposure or working conditions, limited access to health services, and poverty. In response to a resolution approved by the Directing Council of the Pan American Health Organization (PAHO) in 2013, PAHO, the U.S. Centers for Disease Control and Prevention, and the Latin American Society of Nephrology and Hypertension (SLANH) organized a consultation process in order to expand knowledge on the epidemic of CKDnT and to develop appropriate surveillance instruments. The Clinical Working Group from SLANH was put in charge of finding a consensus definition of a confirmed clinical case of CKDnT. The resulting definition establishes mandatory criteria and exclusion criteria necessary for classifying a case of CKDnT. The definition includes a combination of universally accepted definitions of CKD and the main clinical manifestations of CKDnT. Based on the best available evidence, the Clinical Working Group also formulated general recommendations about clinical management that apply to any patient with CKDnT. Adhering to the definition of a confirmed clinical case of CKDnT and implementing it appropriately is expected to be a powerful instrument for understanding the prevalence of the epidemic, evaluating the results of interventions, and promoting appropriate advocacy and planning efforts.

  3. Children’s Migration to the United States from Mexico and Central America: Evidence from the Mexican and Latin American Migration Projects

    Directory of Open Access Journals (Sweden)

    Katharine M. Donato

    2015-02-01

    Full Text Available In light of rising numbers of unaccompanied minors at the Mexico-US border in 2014, this article examines child migration from Mexico, Guatemala, El Salvador, Costa Rica, and Nicaragua. Using data from the Mexican and Latin American Migration Projects that permit us to go beyond simple descriptive analysis about children apprehended at the border, we investigate the extent to which children from these countries: (1 enter without legal authorization to do so; (2 are more likely to cross the border now than in the past; and (3 are tied to their parents’ migration. In theory, if immigration and refugee protections worked well for children and offered them legal pathways to reunify with their families, then we would expect low levels of unauthorized entry and no dramatic shifts over time. However, our examination of child migration shows that it is strongly linked to unauthorized entry, period of entry, and parents’ US experience.The findings show that the migration of children is closely linked to their parents’ migration history. Although the overall likelihood of a Mexican child making a first US trip is quite low, it is practically non-existent for children whose parents have no US experience. Thus, the increase in child migration from Central America, and the continued high levels of child migration from Mexico result from widespread migration networks and the United States’ long-standing reliance on the children’s parents as immigrant workers. The findings suggest that these children need protection in the form of family reunification and permanent legal status.

  4. Health care providers and human trafficking: what do they know, what do they need to know? Findings from the Middle East, the Caribbean and Central America.

    Directory of Open Access Journals (Sweden)

    Roderik F Viergever

    2015-01-01

    Full Text Available BackgroundHuman trafficking is a crime that commonly results in acute and chronic physical and psychological harm. To foster more informed health sector responses to human trafficking, training sessions for health care providers were developed and pilot-tested in the Middle East, Central America and the Caribbean. This study presents the results of an investigation into what health care providers knew and needed to know about human trafficking as part of that training program.MethodsParticipants attended one of seven two-day training courses in Antigua and Barbuda, Belize, Costa Rica, Egypt, El Salvador, Guyana and Jordan. We assessed participants’ knowledge about human trafficking and opinions about appropriate responses in trafficking cases via questionnaires pre-training, and considered participant feedback about the training post-training. Results178 participants attended the trainings. Pre-training questionnaires were completed by 165 participants (93% and post-training questionnaires by 156 participants (88%. Pre-training knowledge about health and human trafficking appeared generally high for topics such as the international nature of trafficking and the likelihood of poor mental health outcomes among survivors. However, many participants had misconceptions about the characteristics of trafficked persons and a provider’s role in responding to cases of trafficking. The most valued training components included the Role of the Health Provider, Basic Definitions and Concepts and Health Consequences of Trafficking. DiscussionTraining health care providers on caring for trafficked persons has the potential to improve practitioners’ knowledge about human trafficking and its health consequences, and to increase safe practices when responding in cases of trafficking. This study provides lessons for the design of training programs on human trafficking that aim to help health care providers identify and refer victims, and provide care for

  5. Health care providers and human trafficking: what do they know, what do they need to know? Findings from the middle East, the Caribbean, and central america.

    Science.gov (United States)

    Viergever, Roderik F; West, Haley; Borland, Rosilyne; Zimmerman, Cathy

    2015-01-01

    Human trafficking is a crime that commonly results in acute and chronic physical and psychological harm. To foster more informed health sector responses to human trafficking, training sessions for health care providers were developed and pilot-tested in the Middle East, Central America, and the Caribbean. This study presents the results of an investigation into what health care providers knew and needed to know about human trafficking as part of that training program. Participants attended one of seven two-day training courses in Antigua and Barbuda, Belize, Costa Rica, Egypt, El Salvador, Guyana, and Jordan. We assessed participants' knowledge about human trafficking and opinions about appropriate responses in trafficking cases via questionnaires pre-training, and considered participant feedback about the training post-training. 178 participants attended the trainings. Pre-training questionnaires were completed by 165 participants (93%) and post-training questionnaires by 156 participants (88%). Pre-training knowledge about health and human trafficking appeared generally high for topics such as the international nature of trafficking and the likelihood of poor mental health outcomes among survivors. However, many participants had misconceptions about the characteristics of trafficked persons and a provider's role in responding to cases of trafficking. The most valued training components included the "Role of the Health Provider," "Basic Definitions and Concepts," and "Health Consequences of Trafficking." Training health care providers on caring for trafficked persons has the potential to improve practitioners' knowledge about human trafficking and its health consequences, and to increase safe practices when responding in cases of trafficking. This study provides lessons for the design of training programs on human trafficking that aim to help health care providers identify and refer victims, and provide care for survivors.

  6. PEER NGA-East Overview: Development of a Ground Motion Characterization Model (Ground Motion Prediction Equations) for Central and Eastern North America

    Science.gov (United States)

    Goulet, C. A.; Abrahamson, N. A.; Al Atik, L.; Atkinson, G. M.; Bozorgnia, Y.; Graves, R. W.; Kuehn, N. M.; Youngs, R. R.

    2017-12-01

    The Next Generation Attenuation project for Central and Eastern North America (CENA), NGA-East, is a major multi-disciplinary project coordinated by the Pacific Earthquake Engineering Research Center (PEER). The project was co-sponsored by the U.S. Nuclear Regulatory Commission (NRC), the U.S. Department of Energy (DOE), the Electric Power Research Institute (EPRI) and the U.S. Geological Survey (USGS). NGA-East involved a large number of participating researchers from various organizations in academia, industry and government and was carried-out as a combination of 1) a scientific research project and 2) a model-building component following the NRC Seismic Senior Hazard Analysis Committee (SSHAC) Level 3 process. The science part of the project led to several data products and technical reports while the SSHAC component aggregated the various results into a ground motion characterization (GMC) model. The GMC model consists in a set of ground motion models (GMMs) for median and standard deviation of ground motions and their associated weights, combined into logic-trees for use in probabilistic seismic hazard analyses (PSHA). NGA-East addressed many technical challenges, most of them related to the relatively small number of earthquake recordings available for CENA. To resolve this shortcoming, the project relied on ground motion simulations to supplement the available data. Other important scientific issues were addressed through research projects on topics such as the regionalization of seismic source, path and attenuation of motions, the treatment of variability and uncertainties and on the evaluation of site effects. Seven working groups were formed to cover the complexity and breadth of topics in the NGA-East project, each focused on a specific technical area. This presentation provides an overview of the NGA-East research project and its key products.

  7. Market regulation in Central America and Bit-Energy.CEL as tool for improving the self regulating forces for a liberalised market

    International Nuclear Information System (INIS)

    Reisinger, H.; Reuter, A.; Dulle, H.

    2002-01-01

    establishment of regional spot and contracts market comprising 6 Central American countries; 3. the introduction of a retail market, allowing auto generation for industrial consumers; 4. the introduction of a renewable and rural electrification support scheme; 5. the introduction of the stochastic planning tool Bit-Energy.CEL for making offers for the spot market less predictable and more flexible. The proposed paper will show more details on the history of market liberalisation in Central America, summarise ongoing activities for improving market efficiency and explain in more detail which role Bit-Energy.CEL plays in this process. (author)

  8. Effectiveness of a combination prevention strategy for HIV risk reduction with men who have sex with men in Central America: a mid-term evaluation.

    Science.gov (United States)

    Firestone, Rebecca; Rivas, Jorge; Lungo, Susana; Cabrera, Alejandra; Ruether, Susan; Wheeler, Jennifer; Vu, Lung

    2014-12-04

    package. However, those reached are able to practice HIV prevention. Combination prevention is a promising approach in Central America, requiring expansion in coverage and intensity.

  9. Climate Impacts of Deforestation/Land-Use Changes in Central South America in the PRECIS Regional Climate Model: Mean Precipitation and Temperature Response to Present and Future Deforestation Scenarios

    OpenAIRE

    Canziani, Pablo O.; Carbajal Benitez, Gerardo

    2012-01-01

    Deforestation/land-use changes are major drivers of regional climate change in central South America, impacting upon Amazonia and Gran Chaco ecoregions. Most experimental and modeling studies have focused on the resulting perturbations within Amazonia. Using the Regional Climate Model PRECIS, driven by ERA-40 reanalysis and ECHAM4 Baseline model for the period 1961–2000 (40-year runs), potential effects of deforestation/land-use changes in these and other neighboring ecoregions are evaluated....

  10. Xylella fastidiosa CoDiRO strain associated with the olive quick decline syndrome in southern Italy belongs to a clonal complex of the subspecies pauca that evolved in Central America.

    Science.gov (United States)

    Marcelletti, Simone; Scortichini, Marco

    2016-12-01

    Xylella fastidiosa, a xylem-limited bacterium transmitted by xylem-fluid-feeding Hemiptera insects, causes economic losses of both woody and herbaceous plant species. A Xyl. fastidiosa subsp. pauca strain, namely CoDiRO, was recently found to be associated with the 'olive quick decline syndrome' in southern Italy (i.e. Apulia region). Recently, some Xyl. fastidiosa strains intercepted in France from Coffea spp. plant cuttings imported from Central and South America were characterized. The introduction of infected plant material from Central America in Apulia was also postulated even though an ad hoc study to confirm this hypothesis is lacking. In the present study, we assessed the complete and draft genome of 27 Xyl. fastidiosa strains. Through a genome-wide approach, we confirmed the occurrence of three subspecies within Xyl. fastidiosa, namely fastidiosa, multiplex and pauca, and demonstrated the occurrence of a genetic clonal complex of four Xyl. fastidiosa strains belonging to subspecies pauca which evolved in Central America. The CoDiRO strain displayed 13 SNPs when compared with a strain isolated in Costa Rica from Coffea sp. and 32 SNPs when compared with two strains obtained from Nerium oleander in Costa Rica. These results support the close relationships of the two strains. The four strains in the clonal complex contain prophage-like genes in their genomes. This study strongly supports the possibility of the introduction of Xyl. fastidiosa in southern Italy via coffee plants grown in Central America. The data also stress how the current global circulation of agricultural commodities potentially threatens the agrosystems worldwide.

  11. Seismicity of the Earth 1900-2013, seismotectonics of South America (Nazca Plate Region)

    Science.gov (United States)

    Hayes, Gavin P.; Smoczyk, Gregory M.; Benz, Harley M.; Furlong, Kevin P.; Villaseñor, Antonio

    2015-01-01

    The South American arc extends over 7,000 kilometers (km), from the Chilean margin triple junction offshore of southern Chile, to its intersection with the Panama fracture zone, offshore of the southern coast of Panama in Central America. It marks the plate boundary between the subducting Nazca plate and the South America plate, where the oceanic crust and lithosphere of the Nazca plate begin their descent into the mantle beneath South America. The convergence associated with this subduction process is responsible for the uplift of the Andes Mountains, and for the active volcanic chain present along much of this deformation front. Relative to a fixed South America plate, the Nazca plate moves slightly north of eastwards at a rate varying from approximately 80 millimeters/year (mm/yr) in the south, to approximately 65 mm/yr in the north. Although the rate of subduction varies little along the entire arc, there are complex changes in the geologic processes along the subduction zone that dramatically influence volcanic activity, crustal deformation, earthquake generation and occurrence all along the western edge of South America.

  12. A Novel Educational Strategy Targeting Health Care Workers in Underserved Communities in Central America to Integrate HIV into Primary Medical Care

    Science.gov (United States)

    Flys, Tamara; González, Rosalba; Sued, Omar; Suarez Conejero, Juana; Kestler, Edgar; Sosa, Nestor; McKenzie-White, Jane; Monzón, Irma Irene; Torres, Carmen-Rosa; Page, Kathleen

    2012-01-01

    Background Current educational strategies to integrate HIV care into primary medical care in Central America have traditionally targeted managers or higher-level officials, rather than local health care workers (HCWs). We developed a complementary online and on-site interactive training program to reach local HCWs at the primary care level in underserved communities. Methods The training program targeted physicians, nurses, and community HCWs with limited access to traditional onsite training in Panama, Nicaragua, Dominican Republic, and Guatemala. The curriculum focused on principles of HIV care and health systems using a tutor-supported blended educational approach of an 8-week online component, a weeklong on-site problem-solving workshop, and individualized project-based interventions. Results Of 258 initially active participants, 225 (225/258 = 87.2%) successfully completed the online component and the top 200 were invited to the on-site workshop. Of those, 170 (170/200 = 85%) attended the on-site workshop. In total, 142 completed all three components, including the project phase. Quantitative and qualitative evaluation instruments included knowledge assessments, reflexive essays, and acceptability surveys. The mean pre and post-essay scores demonstrating understanding of social determinants, health system organization, and integration of HIV services were 70% and 87.5%, respectively, with an increase in knowledge of 17.2% (p<0.001). The mean pre- and post-test scores evaluating clinical knowledge were 70.9% and 90.3%, respectively, with an increase in knowledge of 19.4% (p<0.001). A survey of Likert scale and open-ended questions demonstrated overwhelming participant satisfaction with course content, structure, and effectiveness in improving their HIV-related knowledge and skills. Conclusion This innovative curriculum utilized technology to target HCWs with limited access to educational resources. Participants benefited from technical skills acquired

  13. A novel educational strategy targeting health care workers in underserved communities in Central America to integrate HIV into primary medical care.

    Directory of Open Access Journals (Sweden)

    Tamara Flys

    Full Text Available BACKGROUND: Current educational strategies to integrate HIV care into primary medical care in Central America have traditionally targeted managers or higher-level officials, rather than local health care workers (HCWs. We developed a complementary online and on-site interactive training program to reach local HCWs at the primary care level in underserved communities. METHODS: The training program targeted physicians, nurses, and community HCWs with limited access to traditional onsite training in Panama, Nicaragua, Dominican Republic, and Guatemala. The curriculum focused on principles of HIV care and health systems using a tutor-supported blended educational approach of an 8-week online component, a weeklong on-site problem-solving workshop, and individualized project-based interventions. RESULTS: Of 258 initially active participants, 225 (225/258=87.2% successfully completed the online component and the top 200 were invited to the on-site workshop. Of those, 170 (170/200=85% attended the on-site workshop. In total, 142 completed all three components, including the project phase. Quantitative and qualitative evaluation instruments included knowledge assessments, reflexive essays, and acceptability surveys. The mean pre and post-essay scores demonstrating understanding of social determinants, health system organization, and integration of HIV services were 70% and 87.5%, respectively, with an increase in knowledge of 17.2% (p<0.001. The mean pre- and post-test scores evaluating clinical knowledge were 70.9% and 90.3%, respectively, with an increase in knowledge of 19.4% (p<0.001. A survey of Likert scale and open-ended questions demonstrated overwhelming participant satisfaction with course content, structure, and effectiveness in improving their HIV-related knowledge and skills. CONCLUSION: This innovative curriculum utilized technology to target HCWs with limited access to educational resources. Participants benefited from technical skills

  14. Increased prevalence of Plasmodium falciparum malaria in Honduras, Central America Aumento de la prevalencia de malaria por Plasmodium falciparum en Honduras, Centroamerica

    Directory of Open Access Journals (Sweden)

    Carol J. Palmer

    1998-07-01

    Full Text Available We report on our investigation of a malaria outbreak in Honduras, Central America, in January 1997. We tested 202 patients with fever and chills using thin and thick blood film microscopy. Sixteen patients lived in the city and the rest lived in rural areas. A total of 95 samples (47% were positive for malaria parasites. Seventy-nine percent (63/80 of the rural patients were infected with Plasmodium vivax and 21% (17/80 were infected with P. falciparum. In the urban area, all 15 infected patients had P. vivax malaria and none showed evidence of P. falciparum. Since previous reports indicate that falciparum malaria accounts for only 2% of the overall malaria infections in Honduras, the results reported here suggest that there is a dramatic increase in falciparum malaria in the area of Honduras investigated in this study.Notificamos los resultados de un estudio de un brote de malaria que se produjo en Honduras, Centroamérica, en enero de 1997. Sometimos a examen microscópico frotis delgados y frotis gruesos de la sangre de 202 pacientes con fiebre y escalofríos. Dieciséis pacientes eran habitantes de la zona urbana y el resto de la zona rural. Un total de 95 especímenes (47% fueron positivos a parásitos de la malaria. Setenta y ocho por ciento (62/80 de los pacientes del área rural estaban infestados con Plasmodium vivax y 22% (17/80 con P. falciparum. En la zona urbana, todos los 15 pacientes que estaban infestados tenían P. vivax y en ninguno se detectó P. falciparum. Ya que según informes previos la malaria de tipo falciparum representa solamente 2% de todos los casos de malaria en Honduras, nuestros resultados sugieren que hay un gran incremento del número de casos de malaria falciparum en la zona de Honduras en que se llevó a cabo esta investigación.

  15. Discovery of new Ohbayashinema spp. (Nematoda: Heligmosomoidea) in Ochotona princeps and Ochotona cansus (Lagomorpha: Ochotonidae) from western North America and Central Asia, with considerations of historical biogeography.

    Science.gov (United States)

    Durette-Desset, M-C; Galbreath, K E; Hoberg, E P

    2010-06-01

    Three new species of Ohbayashinema (Nematoda, Heligmosomoidea) are described from localities in western North America and central Asia. Two of these species, Ohbayashinema nearctica n. sp. and Ohbayashinema aspeira n. sp., are parasitic in American pika, Ochotona princeps. Ohbayashinema nearctica is differentiated from the 5 known species of the genus parasitic in Ochotonidae from the Old World by very long spicules and an oblique axis of orientation for the ridges composing the synlophe. Ohbayashinema aspeira, described only from females, is similar to Oh. nearctica based on the number of cuticular ridges at the mid-body. It is mainly differentiated by an uncoiled anterior extremity and by near equal dimensions of the vestibule and the uterus. The third species, Ohbayashinema patriciae n. sp., is parasitic in Gansu pika, Ochotona cansus , from China. It is similar to Ohbayashinema erbaevae parasitic in Ochotona dauurica from Buriatia and Ohbayashinema ochotoni in Ochotona macrotis from Nepal, based on the length of the spicules and the ratio of spicule length to body length. It differs from the former species by possessing a smaller number of cuticular ridges and in the comparative length of the vestibule and infundibulum. Related to Oh. ochotoni by an identical number of cuticular ridges at the mid-body, it differs from this species in having smaller ridges in the dorsal rather than ventral field and in the dimensions of the dorsal ray where rays 9 are less than rays 10. Species of Ohbayashinema appear to be host-specific among the Ochotonidae but had not been previously reported in pikas from the Nearctic. Although much remains to be demonstrated about the diversity for helminths in pikas, it is apparent that factors associated with the assembly and structure of parasite faunas have been complex, involving episodic processes for geographic and host colonization along with coevolutionary mechanisms. Understanding the historical factors, particularly climate

  16. The integripennis species group of Geocharidius Jeannel, 1963 (Carabidae, Bembidiini, Anillina) from Nuclear Central America: a taxonomic review with notes about biogeography and speciation.

    Science.gov (United States)

    Sokolov, Igor M; Kavanaugh, David H

    2014-01-01

    Our review recognizes 15 species of the integripennis species group of Geocharidius from Nuclear Central America, include three species previously described (Geocharidiusgimlii Erwin, Geocharidiusintegripennis (Bates) and Geocharidiuszullinii Vigna Taglianti) and 12 described here as new. They are: Geocharidiusandersoni sp. n. (type locality: Chiapas, Chiapas Highlands, Cerro Huitepec) and Geocharidiusvignatagliantii sp. n. (type locality: Chiapas, Motozintla, Sierra Madre de Chiapas, Benito Juárez) from Mexico; Geocharidiusantigua sp. n. (type locality: Sacatepéquez, 5 km SE of Antigua), Geocharidiusbalini sp. n. (type locality: Suchitepéquez, 4 km S of Volcan Atitlán), Geocharidiuserwini sp. n. (type locality: Quiché Department, 7 km NE of Los Encuentros), Geocharidiusjalapensis sp. n. (type locality: Jalapa Department, 4 km E of Mataquescuintla), Geocharidiuslonginoi, sp. n. (type locality: El Progreso Department, Cerro Pinalón), and Geocharidiusminimus sp. n. (type locality: Sacatepéquez Department, 5 km SE of Antigua) from Guatemala; and Geocharidiuscelaquensis sp. n. (type locality: Lempira Department, Celaque National Park), Geocharidiuscomayaguanus sp. n. (type locality: Comayagua Department, 18 km ENE of Comayagua), Geocharidiusdisjunctus sp. n. (type locality: Francisco Morazán, La Tigra National Park), and Geocharidiuslencanus sp. n. (type locality: Lempira Department, Celaque National Park) from Honduras. For all members of the group, adult structural characters, including male and female genitalia, are described, and a taxonomic key for all members of the integripennis species group is presented based on these characters. Behavioral and biogeographical aspects of speciation in the group are discussed, based on the morphological analysis. In all cases of sympatry, pairs of closely related species show greater differences in sizes than pairs of more remotely related species. Integripennis group species occupy six different montane areas at

  17. The integripennis species group of Geocharidius Jeannel, 1963 (Carabidae, Bembidiini, Anillina from Nuclear Central America: a taxonomic review with notes about biogeography and speciation

    Directory of Open Access Journals (Sweden)

    Igor Sokolov

    2014-09-01

    Full Text Available Our review recognizes 15 species of the integripennis species group of Geocharidius from Nuclear Central America, include three species previously described (G. gimlii Erwin, G. integripennis (Bates and G. zullinii Vigna Taglianti and 12 described here as new. They are: G. andersoni sp. n. (type locality: Chiapas, Chiapas Highlands, Cerro Huitepec and G. vignatagliantii sp. n. (type locality: Chiapas, Motozintla, Sierra Madre de Chiapas, Benito Juárez from Mexico; G. antigua sp. n. (type locality: Sacatepéquez, 5 km SE of Antigua, G. balini sp. n. (type locality: Suchitepéquez, 4 km S of Volcan Atitlán, G. erwini sp. n. (type locality: Quiché Department, 7 km NE of Los Encuentros, G. jalapensis sp. n. (type locality: Jalapa Department, 4 km E of Mataquescuintla, G. longinoi, sp. n. (type locality: El Progreso Department, Cerro Pinalón, and G. minimus sp. n. (type locality: Sacatepéquez Department, 5 km SE of Antigua from Guatemala; and G. celaquensis sp. n. (type locality: Lempira Department, Celaque National Park, G. comayaguanus sp. n. (type locality: Comayagua Department, 18 km ENE of Comayagua, G. disjunctus sp. n. (type locality: Francisco Morazán, La Tigra National Park, and G. lencanus sp. n. (type locality: Lempira Department, Celaque National Park from Honduras. For all members of the group, adult structural characters, including male and female genitalia, are described, and a taxonomic key for all members of the integripennis species group is presented based on these characters. Behavioral and biogeographical aspects of speciation in the group are discussed, based on the morphological analysis. In all cases of sympatry, pairs of closely related species show greater differences in sizes than pairs of more remotely related species. Integripennis group species occupy six different montane areas at elevations above 1300m, with no species shared among them. Major faunal barriers in the region limiting present species distributions

  18. The Cocos Ridge drives collision of Panama with northwestern South America

    Science.gov (United States)

    LaFemina, Peter; Govers, Rob; Mora-Paez, Hector; Geirsson, Halldor; Cmacho, Eduardo

    2015-04-01

    The collision of the Panamanian isthmus with northwestern South America is thought to have initiated as early as Oligocene - Miocene time (23-25 Ma) based on geologic and geophysical data and paleogeographic reconstructions. This collision was driven by eastward-directed subduction beneath northwestern South America. Cocos - Caribbean convergence along the Middle America Trench, and Nazca - Caribbean oblique convergence along the South Panama Deformed Belt have resulted in complex deformation of the southwestern Caribbean since Miocene - Pliocene time. Subduction and collision of the aseismic Cocos Ridge is thought to have initiated migration of the volcanic arc toward the back-arc; 3) Quaternary to present deformation within the Central Costa Rica Deformed Belt; 4) Quaternary to present shortening across the fore-arc Fila Costeña fold and thrust belt and back-arc North Panama Deformed Belt (NPDB); 5) Quaternary to present outer fore-arc uplift of Nicoya Peninsula above the seamount domain, and the Osa and Burica peninsulas above the ridge; and 6) Pleistocene to present northwestward motion of the Central American Fore Arc (CAFA) and northeastward motion of the Panama Region. We investigate the geodynamic effects of Cocos Ridge collision on motion of the Panama Region with a new geodynamic model. The model is compared to a new 1993-2015 GPS-derived three-dimensional velocity field for the western Caribbean and northwestern South America. Specifically, we test the hypotheses that the Cocos Ridge is the main driver for upper plate deformation in the western Caribbean. Our models indicate that Cocos Ridge collision drives northwest-directed motion of the CAFA and the northeast-directed motion of the Panama Region. The Panama Region is driven into the Caribbean across the NPDB and into northwestern South America, which is also converging with the Panama Region, pushing it toward the west-northwest. Therefore, modern collision of Panama with northwestern South America

  19. The structure of the crust and uppermost mantle beneath Madagascar

    Science.gov (United States)

    Andriampenomanana, Fenitra; Nyblade, Andrew A.; Wysession, Michael E.; Durrheim, Raymond J.; Tilmann, Frederik; Julià, Jordi; Pratt, Martin J.; Rambolamanana, Gérard; Aleqabi, Ghassan; Shore, Patrick J.; Rakotondraibe, Tsiriandrimanana

    2017-09-01

    , markedly slow shear-wave velocities (4.2-4.3 km s-1) are observed beneath the northern tip, central part and southwestern region of the island where the major Cenozoic volcanic provinces are located, implying the lithosphere has been significantly modified in these places.

  20. A questão do banimento internacional das minas terrestres: novos atores na segurança internacional e os casos das Américas Central e do Sul The international ban on landmines: new actors in international security and the cases of Central America and South America

    Directory of Open Access Journals (Sweden)

    James Augusto Pires Tibúrcio

    2011-12-01

    Full Text Available O principal instrumento jurídico internacional destinado a banir o uso, a produção e as transferências internacionais de minas terrestres antipessoais é o Tratado de Ottawa, aprovado em 1997 e que, em junho de 2011, possuía 156 Estados signatários. No processo que conduziu à sua aprovação, diversas organizações da sociedade civil, em vários países, desempenharam papel de destaque por meio de uma forte pressão exercida sobre alguns governos nacionais, promovendo uma campanha de amplo impacto midiático e que obteve apoio de algumas celebridades, especialmente de Diana, princesa de Gales. O presente artigo tem como objetivo discutir a questão do banimento das minas terrestres antipessoais a partir dessa perspectiva, demonstrando que, em alguns temas com consequências humanitárias negativas muito evidentes, é possível que os governos reajam positivamente às pressões da sociedade civil. Ademais, também se analisa como o problema das minas terrestres antipessoais foi enfrentado na América Central e na América do Sul, destacando-se, ainda, o papel do Brasil no apoio às ações de desminagem nestas regiões.The main international legal instrument for banning the use, production and international transfers of antipersonnel landmines is the Ottawa Treaty, approved in 1997, which in June 2011 had 156 signatory states. In the process leading to its approval, several civil society organizations, in many countries, played a prominent role through heavy pressure on some governments, promoting a campaign of huge media impact with support from some celebrities, notably Diana, Princess of Wales. This paper shows that in some areas with very obvious negative humanitarian consequences, it is possible that governments react positively to civil society pressures. Furthermore, this paper also examines how the problem of antipersonnel landmines has been tackled in Central and South America, also touching on Brazil's role in supporting the

  1. Implications of the Central America-Dominican Republic-Free Trade Agreement for the nutrition transition in Central America Implicaciones del Tratado de Libre Comercio entre Centroamérica y República Dominicana sobre la transición alimentaria en Centroamérica

    Directory of Open Access Journals (Sweden)

    Corinna Hawkes

    2008-11-01

    Full Text Available OBJECTIVES: To identify potential impacts of the Central America-Dominican Republic-Free Trade Agreement (CAFTA-DR on food consumption patterns associated with the nutrition transition, obesity, and diet-related chronic diseases. METHODS: Examination of CAFTA-DR agreement to identify measures that have the potential to affect food availability and retail prices. RESULTS: CAFTA-DR includes agreements on tariffs, tariff-rate quotas (TRQs, and sanitary and phytosanitary regulations with direct implications for the availability and prices of various foods. Agreements on investment, services, and intellectual property rights (IPR are also relevant because they create a business climate more conducive to long-term investment by the transnational food industry. Trade liberalization under CAFTA-DR is likely to increase availability and lower relative prices of two food groups associated with the nutrition transition: meat and processed foods. These outcomes are expected to occur as the direct result of increased imports from the United States and increased production by U.S. companies based in Central America, and the indirect result of increased domestic meat production (due to increased availability of cheaper animal feed and increased production of processed foods by domestic companies (due to a more competitive market environment. CONCLUSIONS: CAFTA-DR is likely to further the nutrition transition in Central America by increasing the consumption of meat; highly processed foods; and new, non-traditional foods. The public health community should be more aware of the implications of trade agreements for dietary health. Governments and related stakeholders should assess the coherence between changes fostered by specific trade agreements with national policies on diet and nutrition.OBJETIVOS: Identificar el posible impacto del Tratado de Libre Comercio entre Centroamérica y República Dominicana (TLCCA-RD sobre el patrón de consumo de alimentos

  2. British and Israeli Assistance to U.S. Strategies of Torture and Counter- insurgency in Central and Latin America, 1967-96: An Argument Against Complexification

    Directory of Open Access Journals (Sweden)

    Ian Almond

    2013-01-01

    Full Text Available Although the role of the U.S. in supporting the anti-democratic, counter-revolutionary movements, governments, and dictatorships that flourished in Latin America from the 1960s to the 1990s is well known, this article examines the support provided to the U.S. by other countries. Principally this support was provided by Israel and the United Kingdom, but other countries were also involved, such as South Africa, Taiwan, France, and even Saudi Arabia. The article argues that a clear material framework underlies the assistance given by these countries. It also identifies a number of cultural and historical reasons why anti-democratic governments in Latin America found particular political empathy in Israel.

  3. Lower crustal intrusions beneath the southern Baikal Rift Zone

    DEFF Research Database (Denmark)

    Nielsen, Christoffer; Thybo, Hans

    2009-01-01

    The Cenozoic Baikal Rift Zone (BRZ) is situated in south-central Siberia in the suture between the Precambrian Siberian Platform and the Amurian plate. This more than 2000-km long rift zone is composed of several individual basement depressions and half-grabens with the deep Lake Baikal at its...... centre. The BEST (Baikal Explosion Seismic Transect) project acquired a 360-km long, deep seismic, refraction/wide-angle reflection profile in 2002 across southern Lake Baikal. The data from this project is used for identification of large-scale crustal structures and modelling of the seismic velocities...... velocities around the rift structure, except for beneath the rift axis where a distinct 50-80-km wide high-velocity anomaly (7.4-7.6 ± 0.2 km/s) is observed. Reverberant or "ringing" reflections with strong amplitude and low frequency originate from this zone, whereas the lower crust is non...

  4. Soil mineral N dynamics beneath mixtures of leaves from legume and fruit trees in Central Amazonian multi-strata agroforests Dinâmica do nitrogênio mineral no solo em misturas de folhas de leguminosas arbóreas e de fruteiras em sistemas agroflorestais multiestratificados na Amazônia Central

    Directory of Open Access Journals (Sweden)

    Carol Melanie Schwendener

    2007-01-01

    Full Text Available Long term applications of leguminous green mulch could increase mineralizable nitrogen (N beneath cupuaçu trees produced on the infertile acidic Ultisols and Oxisols of the Amazon Basin. However, low quality standing cupuaçu litter could interfere with green mulch N release and soil N mineralization. This study compared mineral N, total N, and microbial biomass N beneath cupuaçu trees grown in two different agroforestry systems, north of Manaus, Brazil, following seven years of different green mulch application rates. To test for net interactions between green mulch and cupuaçu litter, dried gliricidia and inga leaves were mixed with senescent cupuaçu leaves, surface applied to an Oxisol soil, and incubated in a greenhouse for 162 days. Leaf decomposition, N release and soil N mineralization were periodically measured in the mixed species litter treatments and compared to single species applications. The effect of legume biomass and cupuaçu litter on soil mineral N was additive implying that recommendations for green mulch applications to cupuaçu trees can be based on N dynamics of individual green mulch species. Results demonstrated that residue quality, not quantity, was the dominant factor affecting the rate of N release from leaves and soil N mineralization in a controlled environment. In the field, complex N cycling and other factors, including soil fauna, roots, and microclimatic effects, had a stronger influence on available soil N than residue quality.Aplicações a longo prazo de leguminosas como adubo verde podem aumentar o nitrogênio (N mineralizável sob árvores de cupuaçu em solos pouco férteis e ácidos (Ultisols e Oxisols da Bacia Amazônica. Entretanto, a baixa qualidade da liteira de cupuaçu pode influênciara liberação de N do adubo verde e a mineralização deste no solo. Neste estudo foram comparados o N mineral, N total, e o N da biomassa microbiana sob árvores de cupuaçu cultivadas em dois sistemas

  5. The Ocean Boundary Layer beneath Hurricane Frances

    Science.gov (United States)

    Dasaro, E. A.; Sanford, T. B.; Terrill, E.; Price, J.

    2006-12-01

    The upper ocean beneath the peak winds of Hurricane Frances (57 m/s) was measured using several varieties of air-deployed floats as part of CBLAST. A multilayer structure was observed as the boundary layer deepened from 20m to 120m in about 12 hours. Bubbles generated by breaking waves create a 10m thick surface layer with a density anomaly, due to the bubbles, of about 1 kg/m3. This acts to lubricate the near surface layer. A turbulent boundary layer extends beneath this to about 40 m depth. This is characterized by large turbulent eddies spanning the boundary layer. A stratified boundary layer grows beneath this reaching 120m depth. This is characterized by a gradient Richardson number of 1/4, which is maintained by strong inertial currents generated by the hurricane, and smaller turbulent eddies driven by the shear instead of the wind and waves. There is little evidence of mixing beneath this layer. Heat budgets reveal the boundary layer to be nearly one dimensional through much of the deepening, with horizontal and vertical heat advection becoming important only after the storm had passed. Turbulent kinetic energy measurements support the idea of reduced surface drag at high wind speeds. The PWP model correctly predicts the degree of mixed layer deepening if the surface drag is reduced at high wind speed. Overall, the greatest uncertainty in understanding the ocean boundary layer at these extreme wind speeds is a characterization of the near- surface processes which govern the air-sea fluxes and surface wave properties.

  6. Assessment of clinical efficacy and safety in a randomized double-blind study of etanercept and sulfasalazine in patients with ankylosing spondylitis from Eastern/Central Europe, Latin America, and Asia.

    Science.gov (United States)

    Damjanov, Nemanja; Shehhi, Waleed Al; Huang, Feng; Kotak, Sameer; Burgos-Vargas, Ruben; Shirazy, Khalid; Bananis, Eustratios; Szumski, Annette; Llamado, Lyndon J Q; Mahgoub, Ehab

    2016-05-01

    Despite the demonstrated efficacy of etanercept for the treatment of ankylosing spondylitis (AS), sulfasalazine is often prescribed, especially in countries with limited access to biologic agents. The objective of this subset analysis of the ASCEND trial was to compare the efficacy of etanercept and sulfasalazine in treating patients with AS from Asia, Eastern/Central Europe, and Latin America. A total of 287 patients, 190 receiving etanercept 50 mg once weekly and 97 receiving sulfasalazine 3 g daily, from eight countries were included in this subset analysis. Differences in disease activity and patient-reported outcomes assessing health-related quality-of-life (HRQoL) parameters in response to treatment were analyzed using the Cochran-Mantel-Haenszel test for categorical efficacy endpoints and analysis of covariance model for continuous variables. At week 16, a significantly greater proportion of patients receiving etanercept achieved ASAS20 (79.0 %) compared with patients receiving sulfasalazine (61.9 %; p = 0.002). At week 16, treatment with etanercept also resulted in significantly better responses than sulfasalazine for ASAS40 (64.7 vs. 35.1 %; p Asia, Central/Eastern Europe, and Latin America.

  7. Use of nuclear and related techniques in studies of agroecological effects resulting from the use of persistent pesticides in Central America. Report of a final research co-ordination meeting

    International Nuclear Information System (INIS)

    1999-09-01

    The use of pesticides for the control of pests of agriculture and vectors of human and animal diseases in the countries of Central America is the highest per capita and one of the most intense in the world. There are reports of acute toxicity and chronic effects among farm workers. There are also reports that pesticide residues in food frequently exceed the Codex Alimentarius Commission's maximum residue levels (MRLs) and shipments of foodstuffs have been rejected by importing countries due to the presence of excessive residues of pesticides. Pesticides are also implicated in the contamination of continental and coastal waters. The indiscriminate use of pesticides would be expected to also aggravate pest problems by adversely affecting populations of beneficial arthropods and causing the development of resistance in pest populations. The Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture initiated a co-ordinated research project in 1992 to generate information on residues of pesticides in the environment, their persistence under local conditions and effect on local species of beneficial arthropods in agricultural and adjacent areas in the countries of Central America. Such information could be used in the implementation of legislation to control the distribution and use of pesticides and the development and application of integrated pest management programmes. Scientists from Costa Rica, Guatemala, Honduras, Nicaragua, Panama and the United States of America participated in this project. This TECDOC reports on the accomplishments of the project and includes the papers presented at the final Research Co-ordination Meeting held in Panama City, Panama, 20-24 April 1998

  8. Building America

    Energy Technology Data Exchange (ETDEWEB)

    Brad Oberg

    2010-12-31

    IBACOS researched the constructability and viability issues of using high performance windows as one component of a larger approach to building houses that achieve the Building America 70% energy savings target.

  9. Mosquitoes of Middle America.

    Science.gov (United States)

    1976-09-30

    adeloupe, 1964-1966. S Cova Garcia, Pablo, Division de Endemias Rurales, Ministerio de Sanidad y Asistencia Social , Mara- cay, Venezuela...Central America. Diaz Najerra , Alfonso, Laboratorio de En tomologia, Instituto de Salubridad y Enfermedades Trop- icales.— Mosquitoes of Mexico , loan of...Saneamiento Ambiental. Minister io de Sanidad y Asistencia Social , Caracas , Venezuela. — Organization of topotypic survey of mosquitoes in Vene zuela

  10. Analysis of groundwater flow beneath ice sheets

    International Nuclear Information System (INIS)

    Boulton, G. S.; Zatsepin, S.; Maillot, B.

    2001-03-01

    The large-scale pattern of subglacial groundwater flow beneath European ice sheets was analysed in a previous report. It was based on a two-dimensional flowline model. In this report, the analysis is extended to three dimensions by exploring the interactions between groundwater and tunnel flow. A theory is developed which suggests that the large-scale geometry of the hydraulic system beneath an ice sheet is a coupled, self-organising system. In this system the pressure distribution along tunnels is a function of discharge derived from basal meltwater delivered to tunnels by groundwater flow, and the pressure along tunnels itself sets the base pressure which determines the geometry of catchments and flow towards the tunnel. The large-scale geometry of tunnel distribution is a product of the pattern of basal meltwater production and the transmissive properties of the bed. The tunnel discharge from the ice margin of the glacier, its seasonal fluctuation and the sedimentary characteristics of eskers are largely determined by the discharge of surface meltwater which penetrates to the bed in the terminal zone. The theory explains many of the characteristics of esker systems and can account for tunnel valleys. It is concluded that the large-scale hydraulic regime beneath ice sheets is largely a consequence of groundwater/tunnel flow interactions and that it is essential similar to non-glacial hydraulic regimes. Experimental data from an Icelandic glacier, which demonstrates measured relationships between subglacial tunnel flow and groundwater flow during the transition from summer to winter seasons for a modern glacier, and which support the general conclusions of the theory is summarised in an appendix

  11. Scope of the United Nations International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families and Its Impact on the Signatory Central America Countries

    Directory of Open Access Journals (Sweden)

    Alfonso Chacón Mata

    2017-06-01

    Full Text Available This paper focuses on the need of studying the main foundations of the United Nations International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families that entered into force in 2003.  To accomplish this purpose, first, ILO regulations on migrant population and labor relations will be reviewed; then, the tool will be deeply analyzed; finally, the article will conclude with the essential evaluations the Committee on Migrant Workers carried out for some countries of the Central America region, signatories of the Convention. It is worth noting that Costa Rica does not currently take part in this tool; but even so the other countries participating in it have already received high valued effects and implications, especially El Salvador and Guatemala, as it is going to be analyzed in this paper.

  12. Decompression Melting beneath the Indonesian Volcanic Front

    Science.gov (United States)

    Kelley, K. A.; Colabella, A.; Sisson, T. W.; Hauri, E. H.; Sigurdsson, H.

    2006-12-01

    Subduction zone magmas are typically characterized by high concentrations of dissolved H2O (up to 6-7 wt%), presumably derived from the subducted plate and ultimately responsible for melt generation in this tectonic setting. Pressure-release melting from upward mantle flow, however, is increasingly cited as a secondary driver of mantle wedge melting. Here we report new SIMS volatile and LA-ICP-MS trace element data for olivine-hosted melt inclusions from Galunggung (GG) and Tambora (TB) volcanoes in the Indonesian subduction zone to evaluate the relative importance of decompression vs. H2O-flux melting beneath arc volcanoes. Prior studies of melt inclusions from Galunggung showed unusually low primary H2O concentrations (~0.5 wt%), implicating decompression as a significant mechanism of mantle melting beneath this volcano (Sisson &Bronto, 1998). Our new data from a larger suite of Galunggung melt inclusions show a bimodal distribution of H2O concentrations: a dominant population with ~0.5 wt% H2O, and a small group with 1.5-2.5 wt% H2O, indicating that a small amount of H2O addition from the slab may also contribute to mantle melting here. New volatile data from Tambora melt inclusions also indicate low primary H2O contents (1-2 wt%), suggesting that decompression melting may be a large-scale characteristic of the Indonesian volcanic front. Our new trace element data show both volcanoes are LREE enriched relative to MORB, but Tambora melts show greater LREE enrichment (La/Sm=1.7-2.7[GG]; 6.0- 9.5[TB]). Galunggung melts have Nb/Y in the range of NMORB (0.1-0.2), whereas Tambora Nb/Y is similar to EMORB (0.3-0.5). Most Tambora melt inclusions also have H2O/Y (Y (200-1000) and H2O/Ce (100-1400) relative to NMORB, suggesting a larger influence from slab-derived H2O despite having lower average H2O concentrations than Tambora. The range of H2O/Y and H2O/Ce at Galunggung, however, is largely within the range of back-arc basin basalts and does not preclude a major

  13. High-resolution sequence stratigraphy of lower Paleozoic sheet sandstones in central North America: The role of special conditions of cratonic interiors in development of stratal architecture

    Science.gov (United States)

    Runkel, Anthony C.; Miller, J.F.; McKay, R.M.; Palmer, A.R.; Taylor, John F.

    2007-01-01

    Well-known difficulties in applying sequence stratigraphic concepts to deposits that accumulated across slowly subsiding cratonic interior regions have limited our ability to interpret the history of continental-scale tectonism, oceanographic dynamics of epeiric seas, and eustasy. We used a multi-disciplinary approach to construct a high-resolution stratigraphic framework for lower Paleozoic strata in the cratonic interior of North America. Within this framework, these strata proved readily amenable to modern sequence stratigraphic techniques that were formulated based on successions along passive margins and in foreland basins, settings markedly different from the cratonic interior. Parasequences, parasequence stacking patterns, systems tracts, maximum flooding intervals, and sequence-bounding unconformities can be confidently recognized in the cratonic interior using mostly standard criteria for identification. The similarity of cratonic interior and foreland basin successions in size, geometry, constituent facies, and local stacking patterns of nearshore parasequences is especially striking. This similarity indicates that the fundamental processes that establish shoreface morphology and determine the stratal expression of retreat and progradation were likewise generally the same, despite marked differences in tectonism, physiography, and bathymetry between the two settings. Our results do not support the widespread perception that Paleozoic cratonic interior successions are so anomalous in stratal geometries, and constitute such a poor record of time, that they are poorly suited for modern sequence stratigraphic analyses. The particular arrangement of stratal elements in the cratonic interior succession we studied is no more anomalous or enigmatic than the variability in architecture that sets all sedimentary successions apart from one another. Thus, Paleozoic strata of the cratonic interior are most appropriately considered as a package that belongs in a

  14. Latin America.

    Science.gov (United States)

    Soni, P. Sarita, Ed.

    1993-01-01

    This serial issue features 6 members of the Indiana University System faculty who have focused their research on Latin America, past and present. The first article, "A Literature of Their Own," highlights Darlene Sadlier's research on Brazilian women's fiction and poetry that has led to an interest in the interplay of Brazilian and…

  15. Latin America.

    Science.gov (United States)

    Greenfield, Gerald Michael

    1986-01-01

    Notes the problematical elements of diversity within Latin America, establishes priorities for the social studies curriculum, and reviews what should be taught about its geography, resources, people, religion, customs, economics, politics, history, and international relationships. Lists Latin American Studies programs and published instructional…

  16. Illiterate America.

    Science.gov (United States)

    Kozol, Jonathan

    Intended for those involved in American social service and educational communities, this book addresses the widespread problem of illiteracy in the United States and the social consequences of this problem. Following an introduction, the chapters in the first section of the book discuss the growing crisis of illiterate America, specifically, the…

  17. Textbook America.

    Science.gov (United States)

    Karp, Walter

    1980-01-01

    Focuses on how political attitudes have been influenced by American history textbooks at various times throughout history. Excerpts from traditional and revisionist textbooks are presented, with emphasis on "America Revised" by Frances FitzGerald. Journal available from Harper's Magazine Co., 2 Park Ave., New York, NY 10016. (DB)

  18. A psychology of liberation for Central America: the unfinished work of Ignacio Martín-Baró (1942-1989).

    Science.gov (United States)

    Gondra, José María

    2013-01-01

    On November 16, 1989 the world was shocked by the news of the assassination of six Jesuits at the campus of the Universidad Centro Americana José Simeón Cañas (UCA) in San Salvador, El Salvador. Among those murdered by government soldiers was Ignacio Martín-Baró, a PhD in social psychology from the University of Chicago who at that time was the Vice-Rector for Academic Affairs and Vice-President of the Interamerican Society of Psychology (SIP). Drawing on Martín-Baró's published writings and non-published academic papers and correspondence, this article traces the evolution of the Spanish-born Jesuit who became a leading authority among Latin American social psychologists. In particular, it analyzes his project of becoming a clinical psychologist under the influence of psychoanalysis, his critical social psychology aimed to "de-ideologize" the oppressed social classes of El Salvador, and his ultimate project of a psychology of liberation for Latin America. Martín-Baró's work came to a tragic end just when it began to bear fruit, but it stands as a testimony to a lifetime committed to the human values of democracy, social justice and service to society's poorest and most neglected.

  19. Prevalence and Social Determinants of Smoking in 15 Countries from North Africa, Central and Western Asia, Latin America and Caribbean: Secondary Data Analyses of Demographic and Health Surveys.

    Science.gov (United States)

    Sreeramareddy, Chandrashekhar T; Pradhan, Pranil Man Singh

    2015-01-01

    Article 20 of the World Health Organisation Framework Convention on Tobacco Control calls for a cross-country surveillance of tobacco use through population-based surveys. We aimed to provide country-level prevalence estimates for current smoking and current smokeless tobacco use and to assess social determinants of smoking. Data from Demographic and Health Surveys done between 2005 and 2012, among men and women from nine North African, Central and West Asian countries and six Latin American and Caribbean countries were analyzed. Weighted country-level prevalence rates were estimated for 'current smoking' and 'current use of smokeless tobacco (SLT) products' among men and women. In each country, social determinants of smoking among men and women were assessed by binary logistic regression analyses by including men's and women's sampling weights to account for the complex survey design. Prevalence of smoking among men was higher than 40% in Armenia (63.1%), Moldova (51.1%), Ukraine (52%), Azerbaijan (49.8 %), Kyrgyz Republic (44.3 %) and Albania (42.52%) but the prevalence of smoking among women was less than 10% in most countries except Ukraine (14.81%) and Jordan (17.96%). The prevalence of smokeless tobacco use among men and women was less than 5% in all countries except among men in the Kyrgyz Republic (10.6 %). Smoking was associated with older age, lower education and poverty among men and higher education and higher wealth among women. Smoking among both men and women was associated with unskilled work, living in urban areas and being single. Smoking among men was very high in Central and West Asian countries. Social pattern of smoking among women that was different from men in education and wealth should be considered while formulating tobacco control policies in some Central and West Asian countries.

  20. Topology of convection beneath the solar surface

    International Nuclear Information System (INIS)

    Stein, R.F.; Nordlund, A.

    1989-01-01

    It is shown that the topology of convection beneath the solar surface is dominated by effects of stratification. Convection in a strongly stratified medium has: (1) gentle expanding structureless warm upflows and (2) strong converging filamentary cool downdrafts. The horizontal flow topology is cellular, with a hierarchy of cell sizes. The small density scale height in the surface layers forces the formation of the solar granulation, which is a shallow surface phenomenon. Deeper layers support successively larger cells. The downflows of small cells close to the surface merge into filamentary downdrafts of larger cells at greater depths, and this process is likely to continue through most of the convection zone. Radiative cooling at the surface provides the entropy-deficient material which drives the circulation. 13 refs

  1. Bubble streams rising beneath an inclined surface

    Science.gov (United States)

    Bird, James; Brasz, Frederik; Kim, Dayoung; Menesses, Mark; Belden, Jesse

    2017-11-01

    Bubbles released beneath a submerged inclined surface can tumble along the wall as they rise, dragging the surrounding fluid with them. This effect has recently regained attention as a method to mitigate biofouling in marine environment, such as a ship hull. It appears that the efficacy of this approach may be related to the velocity of the rising bubbles and the extent that they spread laterally as they rise. Yet, it is unclear how bubble stream rise velocity and lateral migration depend on bubble size, flow rate, and inclination angle. Here we perform systematic experiments to quantify these relationships for both individual bubble trajectories and ensemble average statistics. Research supported by the Office of Naval Research under Grant Number award N00014-16-1-3000.

  2. Genome-Wide Analysis Provides Evidence on the Genetic Relatedness of the Emergent Xylella fastidiosa Genotype in Italy to Isolates from Central America.

    Science.gov (United States)

    Giampetruzzi, Annalisa; Saponari, Maria; Loconsole, Giuliana; Boscia, Donato; Savino, Vito Nicola; Almeida, Rodrigo P P; Zicca, Stefania; Landa, Blanca B; Chacón-Diaz, Carlos; Saldarelli, Pasquale

    2017-07-01

    Xylella fastidiosa is a plant-pathogenic bacterium recently introduced in Europe that is causing decline in olive trees in the South of Italy. Genetic studies have consistently shown that the bacterial genotype recovered from infected olive trees belongs to the sequence type ST53 within subspecies pauca. This genotype, ST53, has also been reported to occur in Costa Rica. The ancestry of ST53 was recently clarified, showing it contains alleles that are monophyletic with those of subsp. pauca in South America. To more robustly determine the phylogenetic placement of ST53 within X. fastidiosa, we performed a comparative analysis based on single nucleotide polymorphisms (SNPs) and the study of the pan-genome of the 27 currently public available whole genome sequences of X. fastidiosa. The resulting maximum-parsimony and maximum likelihood trees constructed using the SNPs and the pan-genome analysis are consistent with previously described X. fastidiosa taxonomy, distinguishing the subsp. fastidiosa, multiplex, pauca, sandyi, and morus. Within the subsp. pauca, the Italian and three Costa Rican isolates, all belonging to ST53, formed a compact phylotype in a clade divergent from the South American pauca isolates, also distinct from the recently described coffee isolate CFBP8072 imported into Europe from Ecuador. These findings were also supported by the gene characterization of a conjugative plasmid shared by all the four ST53 isolates. Furthermore, isolates of the ST53 clade possess an exclusive locus encoding a putative ATP-binding protein belonging to the family of histidine kinase-like ATPase gene, which is not present in isolates from the subspecies multiplex, sandyi, and pauca, but was detected in ST21 isolates of the subspecies fastidiosa from Costa Rica. The clustering and distinctiveness of the ST53 isolates supports the hypothesis of their common origin, and the limited genetic diversity among these isolates suggests this is an emerging clade within subsp

  3. Data Package for Past and Current Groundwater Flow and Contamination beneath Single-Shell Tank Waste Management Areas

    Energy Technology Data Exchange (ETDEWEB)

    Horton, Duane G.

    2007-03-16

    This appendix summarizes historic and recent groundwater data collected from the uppermost aquifer beneath the 200 East and 200 West Areas. Although the area of interest is the Hanford Site Central Plateau, most of the information discussed in this appendix is at the scale of individual single-shell tank waste management areas. This is because the geologic, and thus the hydraulic, properties and the geochemical properties (i.e., groundwater composition) are different in different parts of the Central Plateau.

  4. Seismic scatterer distribution beneath the Wellington region, southernmost part of New Zealand's North Island

    Science.gov (United States)

    Kurashimo, E.; Sato, H.; Iidaka, T.; Ishiyama, T.; Iwasaki, T.; Henrys, S. A.; Sutherland, R.; Stern, T. A.; Savage, M. K.; Okaya, D. A.

    2012-12-01

    A detailed crustal and upper mantle structure of the subducting oceanic lithosphere and the overlying continental crust is inevitably important to constrain the physical process of earthquake occurrence. Structural images of many subduction zones have been obtained: for example, the Kanto region, central Japan (e.g., Sato et al., 2005). In the Kanto region, the Philippine Sea Plate subducts beneath the Tokyo Metropolitan area. Similar tectonic situation is found in the southernmost North Island, New Zealand, where the Pacific plate subducts beneath the Australian plate. It is also noted that capital cities are situated in both the regions. In May of 2011, the second phase of the Seismic Array Hikurangi Experiment (SAHKE) was conducted to obtain the detailed subduction structure beneath the southern North Island. The transect line ran from the Wairarapa coast to Kapiti coast over an 80 km profile. Twelve explosives were fired as controlled seismic source on the survey line between 6-10 km apart. The energy was recorded on 878 seismic stations (294 three-component and 584 vertical sensors) deployed at 100 m spacing and 50 m between Kaitoke and Featherston. Data collected on the survey line have high signal-to-noise ratio, from which we can easily recognize, not only the first arrival phases, but also latter phases. The seismic coda waves are generally interpreted as scattered waves from inhomogeneities in the Earth [e.g., Aki, 1969]. Array recordings of seismic events are useful to locate scatterers. In this study, semblance analysis [Neidell and Tarner, 1971] is applied to our waveform data for imaging seismic scatterer distribution, assuming an isotropic scattering model. To locate scatterers, we established 3-D imaginary grid points beneath the survey area. The velocity structure beneath the survey area was derived by refraction tomography method [Zelt and Barton, 1998], which was used to calculate travel times between a source/receiver to a grid point. If a

  5. Cost-effectiveness analysis of varenicline versus existing smoking cessation strategies in Central America and the Caribbean using the BENESCO model.

    Science.gov (United States)

    Lutz, Manfred A; Lovato, Pedro; Cuesta, Genaro

    2012-02-01

    In Central American countries, the economic burden of tobacco has not been assessed. In Costa Rica, a study demonstrated that tobacco-related diseases represent high costs for the health care system. The aim of this study was to assess the cost-effectiveness of varenicline compared with other existing strategies for smoking cessation within a 10-year time horizon in an adult population cohort from Central American and Caribbean countries using the health care payer's perspective. The Benefits of Smoking Cessation on Outcomes simulation model was used for an adult cohort in Costa Rica (n = 2 474 029), Panama (n = 2 249 676), Nicaragua (n = 3 639 948), El Salvador (n = 4 537 803), and the Dominican Republic (n = 6 528 125) (N = 19 429 581). Smoking cessation therapies compared were varenicline (0.5-2 mg/day) versus bupropion (300 mg/day), nicotine replacement therapy (5-15 mg/day), and unaided cessation. Effectiveness measures were: life-years (LYs) gained and quality-adjusted life-years (QALYs) gained. Resource use and cost data were obtained from a country's Ministry of Health and/or Social Security Institutions (2008-2010). The model used a 5% discount rate for costs (expressed in 2010 US$) and health outcomes. Probabilistic sensitivity analyses were conducted and acceptability curves were constructed. Varenicline reduced smoking-related morbidity, mortality, and health care costs in each country included in the study. Accumulatively, mortality in the varenicline arm was reduced by 1190, 1538, and 2902 smoking-related deaths compared with bupropion, nicotine replacement therapy, and unaided cessation, respectively. The net average cost per additional quitter showed that varenicline was cost-saving when compared with competing alternatives. Regarding LYs and QALYs gained in 10 years, varenicline obtained the greatest number of QALYs and LYs in each country, while unaided cessation obtained the fewest. Cost-effectiveness analyses in all 5 countries showed that

  6. Calosota Curtis (Hymenoptera, Chalcidoidea, Eupelmidae – review of the New World and European fauna including revision of species from the West Indies and Central and North America

    Directory of Open Access Journals (Sweden)

    Gary Gibson

    2010-09-01

    Full Text Available Two of three species previously classified in Calosota Curtis (Hymenoptera: Eupelmidae from the Neotropical region are transferred to Eupelminae. Calosota eneubulus (Walker from Galapagos Islands is transferred to Eupelmus Dalman as Eupelmus (Eupelmus eneubulus (Walker, comb. n., and Calosota silvai (Brèthes from Chile is transferred to Brasema Cameron as Brasema silvai comb. n. Calosota cecidobius (Kieffer from Argentina is retained in Calosota, with reservation, as an unrecognized species. The species of Calosota from the New World excluding South America are revised. Eleven species are recognized, including the seven newly described species Calosota albipalpus sp. n. (Costa Rica, Mexico, USA, Venezuela, Calosota bicolorata sp. n. (USA, Calosota elongata sp. n. (USA, Calosota longivena sp. n. (USA, Calosota panamaensis sp. n. (Panama, Calosota setosa sp. n. (Bahamas, Dominican Republic, USA, and Calosota speculifrons sp. n. (Costa Rica, USA. The 11 regional species and the Palaearctic species Calosota vernalis Curtis are keyed and illustrated. Calosota vernalis is not known to occur in the New World but is included in the key and diagnosed because it has been intercepted in quarantine in Canada. Calosota pseudotsugae Burks is placed in synonymy under Calosota acron (Walker, syn. n., and Calosota kentra Burks, Calosota montana Burks and Calosota septentrionalis Hedqvist are placed in synonymy under Calosota aestivalis Curtis syn. n. Calosota modesta Bolívar y Pieltain is removed from synonymy under Calosota viridis Masi, stat. rev., and Calosota viridis, Calosota matritensis Bolívar y Pieltain, and Calosota coerulea Nikol’skaya are placed in synonymy under Calosota metallica (Gahan, syn. n. Calosota grylli Erdös is confirmed as a separate species from Calosota metallica based on features of both sexes. It is suggested that Calosota ariasi Bolívar y Pieltain may be a synonym of Calosota aestivalis, Calosota bolivari Askew may be a synonym

  7. Identifying biogeochemical processes beneath stormwater infiltration ponds in support of a new best management practice for groundwater protection

    Science.gov (United States)

    O'Reilly, Andrew M.; Chang, Ni-Bin; Wanielista, Martin P.; Xuan, Zhemin; Schirmer, Mario; Hoehn, Eduard; Vogt, Tobias

    2011-01-01

     When applying a stormwater infiltration pond best management practice (BMP) for protecting the quality of underlying groundwater, a common constituent of concern is nitrate. Two stormwater infiltration ponds, the SO and HT ponds, in central Florida, USA, were monitored. A temporal succession of biogeochemical processes was identified beneath the SO pond, including oxygen reduction, denitrification, manganese and iron reduction, and methanogenesis. In contrast, aerobic conditions persisted beneath the HT pond, resulting in nitrate leaching into groundwater. Biogeochemical differences likely are related to soil textural and hydraulic properties that control surface/subsurface oxygen exchange. A new infiltration BMP was developed and a full-scale application was implemented for the HT pond. Preliminary results indicate reductions in nitrate concentration exceeding 50% in soil water and shallow groundwater beneath the HT pond.

  8. Investigating Late Cenozoic Mantle Dynamics beneath Yellowstone

    Science.gov (United States)

    Zhou, Q.; Liu, L.

    2015-12-01

    Recent tomography models (Sigloch, 2011; Schmandt & Lin, 2014) reveal unprecedented details of the mantle structure beneath the United States (U.S.). Prominent slow seismic anomalies below Yellowstone, traditionally interpreted as due to a mantle plume, are restricted to depths either shallower than 200 km or between 500 and 1000 km, but a continuation to greater depth is missing. Compared to fast seismic anomalies, which are usually interpreted as slabs or delaminated lithosphere, origin of deep slow seismic anomalies, especially those in the vicinity of subduction zones, is more enigmatic. As a consequence, both the dynamics and evolution of these slow anomalies remain poorly understood. To investigate the origin and evolution of the Yellowstone slow anomaly during the past 20 Myr, we construct a 4D inverse mantle convection model with a hybrid data assimilation scheme. On the one hand, we use the adjoint method to recover the past evolution of mantle seismic structures beyond the subduction zones. On the other hand, we use a high-resolution forward model to simulate the subduction of the oceanic (i.e., Farallon) plate. During the adjoint iterations, features from these two approaches are blended together at a depth of ~200 km below the subduction zone. In practice, we convert fast and slow seismic anomalies to effective positive and negative density heterogeneities. Our preliminary results indicate that at 20 Ma, the present-day shallow slow anomalies beneath the western U.S. were located inside the oceanic asthenosphere, which subsequently entered the mantle wedge, through the segmented Farallon slab. The eastward encroachment of the slow anomaly largely followed the Yellowstone hotspot track migration. The present deep mantle Yellowstone slow anomaly originated at shallower depths (i.e. transition zone), and was then translated down to the lower mantle accompanying the sinking fast anomalies. The temporal evolution of the slow anomalies suggests that the deep

  9. Overthrusting versus subduction beneath southern Hispaniola

    Science.gov (United States)

    Llanes Estrada, M.; Carbó-Gorosabel, A.; ten Brink, U. S.; Granja Bruña, J.; Flores, C. H.; Villasenor, A.; Davila, J. M.; Pazos, A.

    2011-12-01

    Recent observations of the deformational features on the Muertos compressive margin together with sandbox kinematic and gravity modeling question the hypothesized subduction of the Caribbean plate's interior beneath the eastern Greater Antilles island arc. With the aim of testing such subduction, we carried out a wide-angle seismic transect across the widest part of the Muertos compressive margin (longitude 69°W) in the spring of 2009. Shots were fired along the 200 km transect every 90 seconds from the R/V Hesperides' 3850 cubic inches water-gun array, which, towed at 5 knots, resulted in a shot spacing of ~ 230 m. The seismic signal was recorded by five ocean-bottom seismometers deployed at distance intervals from 30 to 50 km. Adjacent reprocessed reflection seismic lines and previous works provided an initial model of the sediment column and the geometry of upper crustal reflectors. A 2-D forward ray-tracing model of the wide-angle transect outlines the broad-scale crustal structure across the Muertos margin. The Caribbean oceanic slab is imaged underneath the Muertos margin to about 50 km north of the deformation front and up to 19 km depth. A change in crustal p-wave velocity at ~60 km from the deformation front is interpreted to be the boundary between the arc crust and the compressive deformed belt. The Caribbean oceanic crust is not seen extending farther north. Results from gravity modeling using ship data acquired on the seismic profile corroborate a model of an overthrusted Caribbean oceanic slab extending a few tens of km northward from the compressive deformation front and rejects a subduction process, independently of the geometry of the slab used or its angle. In addition to the seismic experiment and the gravity modeling, vertical cross-sections of p-wave global tomography do not show northward inclination of a fast velocity layer into the upper mantle suggesting that the Caribbean plate's interior does not subduct under the Muertos margin. Overall

  10. Spina Bifida Association of America

    Science.gov (United States)

    Exceptional Parent, 1974

    1974-01-01

    The Statement of the Spina Bifida Association of America (SBAA) explains SB as a malformation of the central nervous system, reports the formation of SBAA in 1974, explains SBAA's emphasis on local chapter organization, and describes SBAA services, including a bimonthly publication, public education efforts, and research validation projects. (GW)

  11. A preserved early Ediacaran magmatic arc at the northernmost portion of the Transversal Zone central subprovince of the Borborema Province, Northeastern South America

    Directory of Open Access Journals (Sweden)

    Benjamim Bley de Brito Neves

    Full Text Available ABSTRACT: Magmatic arcs are an essential part of crust-forming events in planet Earth evolution. The aim of this work was to describe an early Ediacaran magmatic arc (ca. 635-580 Ma exposed in the northernmost portion of the Transversal Zone, central subprovince of Borborema Province, northeast Brazil. Our research took advantage of several syntheses by different authors, including theses and dissertations, carried out on magmatic rocks of the study area for the last 30 years. The ca. 750 km long and up to 140 km wide arc, trending ENE-WSW, is preserved to the south of the Patos Lineament, between 35º15' and 42º30'W and 7º15' and 8ºS. About 90 different stocks and batholiths of I-type granitic rocks were mapped along this orogenic zone, preferentially intruding low-grade schists of the Cryogenian-Ediacaran Piancó-Alto Brígida (SPAB belt. Three igneous supersuites are recognized: a epidote-bearing granodiorites and tonalites ("Conceição" type; b high-K calc-alkaline granites ("Itaporanga" type; c biotite granodiorites of trondhjemite affinity ("Serrita" type. A fourth group of peralkalic and shoshonitic rocks occurs to the south of the previous ones, reflecting special tectonic conditions. NNE-SSW trending Paleoproterozoic fold belts, surrounding Archean nuclei, characterize the continental part of the northern lower plate. The oceanic fraction of this lower plate was recycled by subduction and scarce remnants of which may be seen either within the enclosing low-grade schists or as xenoliths within the arc intrusions. The upper continental plate presents WSW-ENE structural trends and is composed of Neoproterozoic fold belts and Paleoproterozoic reworked basement inliers. Available data bear clear evidence of an Ediacaran magmatic arc built at the northern portion of the Transversal Zone in the Borborema Province, northeast Brazil.

  12. Nuclear wastes beneath the deep sea floor

    International Nuclear Information System (INIS)

    Bishop, W.P.; Hollister, C.D.

    1974-01-01

    Projections of energy demands for the year 2000 show that nuclear power will likely be one of our energy sources. But the benefits of nuclear power must be balanced against the drawbacks of its by-product: high-level wastes. While it may become possible to completely destroy or eliminate these wastes, it is at least equally possible that we may have to dispose of them on earth in such a way as to assure their isolation from man for periods of the order of a million years. Undersea regions in the middle of tectonic plates and in the approximate center of major current gyres offer some conceptual promise for waste disposal because of their geologic stability and comparatively low organic productivity. The advantages of this concept and the types of detailed information needed for its accurate assessment are discussed. The technical feasibility of permanent disposal beneath the deep sea floor cannot be accurately assessed with present knowledge, and there is a need for a thorough study of the types and rates of processes that affect this part of the earth's surface. Basic oceanographic research aimed at understanding these processes is yielding answers that apply to this societal need. (U.S.)

  13. Turbulence beneath finite amplitude water waves

    Energy Technology Data Exchange (ETDEWEB)

    Beya, J.F. [Universidad de Valparaiso, Escuela de Ingenieria Civil Oceanica, Facultad de Ingenieria, Valparaiso (Chile); The University of New South Wales, Water Research Laboratory, School of Civil and Environmental Engineering, Sydney, NSW (Australia); Peirson, W.L. [The University of New South Wales, Water Research Laboratory, School of Civil and Environmental Engineering, Sydney, NSW (Australia); Banner, M.L. [The University of New South Wales, School of Mathematics and Statistics, Sydney, NSW (Australia)

    2012-05-15

    Babanin and Haus (J Phys Oceanogr 39:2675-2679, 2009) recently presented evidence of near-surface turbulence generated below steep non-breaking deep-water waves. They proposed a threshold wave parameter a {sup 2}{omega}/{nu} = 3,000 for the spontaneous occurrence of turbulence beneath surface waves. This is in contrast to conventional understanding that irrotational wave theories provide a good approximation of non-wind-forced wave behaviour as validated by classical experiments. Many laboratory wave experiments were carried out in the early 1960s (e.g. Wiegel 1964). In those experiments, no evidence of turbulence was reported, and steep waves behaved as predicted by the high-order irrotational wave theories within the accuracy of the theories and experimental techniques at the time. This contribution describes flow visualisation experiments for steep non-breaking waves using conventional dye techniques in the wave boundary layer extending above the wave trough level. The measurements showed no evidence of turbulent mixing up to a value of a {sup 2}{omega}/{nu} = 7,000 at which breaking commenced in these experiments. These present findings are in accord with the conventional understandings of wave behaviour. (orig.)

  14. Magmatic unrest beneath Mammoth Mountain, California

    Science.gov (United States)

    Hill, David P.; Prejean, Stephanie

    2005-09-01

    Mammoth Mountain, which stands on the southwest rim of Long Valley caldera in eastern California, last erupted ˜57,000 years BP. Episodic volcanic unrest detected beneath the mountain since late 1979, however, emphasizes that the underlying volcanic system is still active and capable of producing future volcanic eruptions. The unrest symptoms include swarms of small ( M ≤ 3) earthquakes, spasmodic bursts (rapid-fire sequences of brittle-failure earthquakes with overlapping coda), long-period (LP) and very-long-period (VLP) volcanic earthquakes, ground deformation, diffuse emission of magmatic CO 2, and fumarole gases with elevated 3He/ 4He ratios. Spatial-temporal relations defined by the multi-parameter monitoring data together with earthquake source mechanisms suggest that this Mammoth Mountain unrest is driven by the episodic release of a volume of CO 2-rich hydrous magmatic fluid derived from the upper reaches of a plexus of basaltic dikes and sills at mid-crustal depths (10-20 km). As the mobilized fluid ascends through the brittle-plastic transition zone and into overlying brittle crust, it triggers earthquake swarm activity and, in the case of the prolonged, 11-month-long earthquake swarm of 1989, crustal deformation and the onset of diffuse CO 2 emissions. Future volcanic activity from this system would most likely involve steam explosions or small-volume, basaltic, strombolian or Hawaiaan style eruptions. The impact of such an event would depend critically on vent location and season.

  15. Channelization of plumes beneath ice shelves

    KAUST Repository

    Dallaston, M. C.

    2015-11-11

    © 2015 Cambridge University Press. We study a simplified model of ice-ocean interaction beneath a floating ice shelf, and investigate the possibility for channels to form in the ice shelf base due to spatial variations in conditions at the grounding line. The model combines an extensional thin-film description of viscous ice flow in the shelf, with melting at its base driven by a turbulent ocean plume. Small transverse perturbations to the one-dimensional steady state are considered, driven either by ice thickness or subglacial discharge variations across the grounding line. Either forcing leads to the growth of channels downstream, with melting driven by locally enhanced ocean velocities, and thus heat transfer. Narrow channels are smoothed out due to turbulent mixing in the ocean plume, leading to a preferred wavelength for channel growth. In the absence of perturbations at the grounding line, linear stability analysis suggests that the one-dimensional state is stable to initial perturbations, chiefly due to the background ice advection.

  16. Relaciones craneométricas entre poblaciones prehispánicas de la Región Central del Territorio Argentino y otras del cono Sur de America

    Directory of Open Access Journals (Sweden)

    Fabra, Mariana

    2005-01-01

    Full Text Available Recientes investigaciones realizadas con muestras procedentes de sitios arqueológicos de las Sierras Centrales han propuesto diversas hipótesis para explicar los procesos de poblamiento humano ocurridos en la región. Debido a su carácter de área geográfica intermedia, las poblaciones asentadas en esta región fueron vinculadas con otras procedentes del área andina, y más recientemente, con poblaciones de las regiones de Cuyo, Litoral y sur del país. Para el presente estudio se seleccionó una muestra de 38 individuos masculinos procedentes de diversos sitios arqueológicos de las provincias de Córdoba y San Luis. Esta muestra se comparó, mediante diversas técnicas de análisis (cluster análisis, componentes principales, con poblaciones procedentes de otras regiones del país y Sudamérica publicadas en la literatura, con el objetivo de establecer relaciones biológicas y analizar así posibles vías de poblamiento de la región. Se trabajó con 24 variables morfométricas, pero a los fines comparativos se emplearon aquellas que hubieran sido analizadas en las poblaciones seleccionadas. Los resultados ponen de manifiesto que la serie Córdoba presenta mayor similitud con poblaciones del sur del país, más precisamente de Chubut, y no con poblaciones andinas o de la zona de Cuyo, como se ha postulado. Por otra parte, cuando se la compara con otras poblaciones de Sudamérica, Córdoba ocupa una posición cercana a poblaciones del sur de Brasil, sugiriendo una posible vía de acceso desde el Este. Se discute la influencia de la selección de variables en la definición de las agrupaciones biológicas.

  17. Fermilab and Latin America

    International Nuclear Information System (INIS)

    Lederman, Leon M.

    2006-01-01

    As Director of Fermilab, starting in 1979, I began a series of meetings with scientists in Latin America. The motivation was to stir collaboration in the field of high energy particle physics, the central focus of Fermilab. In the next 13 years, these Pan American Symposia stirred much discussion of the use of modern physics, created several groups to do collaborative research at Fermilab, and often centralized facilities and, today, still provides the possibility for much more productive North-South collaboration in research and education. In 1992, I handed these activities over to the AAAS, as President. This would, I hoped, broaden areas of collaboration. Such collaboration is unfortunately very sensitive to political events. In a rational world, it would be the rewards, cultural and economic, of collaboration that would modulate political relations. We are not there yet

  18. Pleurodese nos derrames pleurais malignos: um inquérito entre médicos em países da América do Sul e Central Pleurodesis for malignant pleural effusions: a survey of physicians in South and Central America

    Directory of Open Access Journals (Sweden)

    Evaldo Marchi

    2010-12-01

    Full Text Available OBJETIVO: A pleurodese é uma alternativa eficaz no controle dos derrames pleurais malignos, mas existem controvérsias a respeito de sua indicação e técnica. O objetivo deste estudo foi avaliar como é realizada a pleurodese em países da América do Sul e Central. MÉTODOS: Profissionais que realizam pleurodese responderam um questionário sobre critérios de indicação para pleurodese, técnicas utilizadas e desfechos. RESULTADOS: Nossa amostra envolveu 147 profissionais no Brasil, 49 em outros países da América do Sul e 36 em países da América Central. Mais de 50% dos participantes realizavam pleurodese somente se confirmada a malignidade no derrame pleural. Entretanto, escalas de dispneia e de status de performance eram raramente utilizadas para indicar o procedimento. Aproximadamente 75% dos participantes no Brasil e na América Central preferiam realizar a pleurodese somente no caso de recidiva do derrame, e a expansão pulmonar deveria variar de 90% a 100%. O talco slurry foi o agente mais utilizado, instilado via drenos de calibre intermediário. A toracoscopia foi realizada em menos de 25% dos casos. Febre e dor torácica foram os efeitos adversos mais comuns, e empiema ocorreu em OBJECTIVE: Pleurodesis is an effective alternative for the control of malignant pleural effusions. However, there is as yet no consensus regarding the indications for the procedure and the techniques employed therein. The objective of this study was to evaluate how pleurodesis is performed in South and Central America. METHODS: Professionals who perform pleurodesis completed a questionnaire regarding the indications for the procedure, the techniques used therein, and the outcomes obtained. RESULTS: Our sample comprised 147 respondents in Brazil, 49 in other South American countries, and 36 in Central America. More than 50% of the respondents reported performing pleurodesis only if pleural malignancy had been confirmed. However, scores on dyspnea and

  19. Climate impacts of deforestation/land-use changes in Central South America in the PRECIS regional climate model: mean precipitation and temperature response to present and future deforestation scenarios.

    Science.gov (United States)

    Canziani, Pablo O; Carbajal Benitez, Gerardo

    2012-01-01

    Deforestation/land-use changes are major drivers of regional climate change in central South America, impacting upon Amazonia and Gran Chaco ecoregions. Most experimental and modeling studies have focused on the resulting perturbations within Amazonia. Using the Regional Climate Model PRECIS, driven by ERA-40 reanalysis and ECHAM4 Baseline model for the period 1961-2000 (40-year runs), potential effects of deforestation/land-use changes in these and other neighboring ecoregions are evaluated. Current 2002 and estimated 2030 land-use scenarios are used to assess PRECIS's response during 1960-2000. ERA-40 and ECHAM4 Baseline driven runs yield similar results. Precipitation changes for 2002 and 2030 land-use scenarios, while significant within deforested areas, do not result in significant regional changes. For temperature significant changes are found within deforested areas and beyond, with major temperature enhancements during winter and spring. Given the current climate, primary effects of deforestation/land-use changes remain mostly confined to the tropical latitudes of Gran Chaco, and Amazonia.

  20. Early Scholars' Visits to Central America: Reports by Karl Sapper, Walter Lehmann, and Franz Termer, edited by Marilyn Beaudry-Corbett and Ellen T Hardy, Theodore E Gutman, 2000

    Directory of Open Access Journals (Sweden)

    Charles C. Kolb

    2001-05-01

    Full Text Available The Cotsen Institute's Director of Publications is archaeologist Marilyn Beaudry-Corbett, herself a specialist on the production and distribution of archaeological ceramics in Mesoamerica and Central America and a scholar of complex society economic organization. Her colleague and the co-editor of this volume, Ellen Hardy, is a Research Associate at The Cotsen Institute and an expert on mortuary customs of the Nicoya region. Theodore (Ted Gutman (1909-1997 was a longtime supporter of the Institute at UCLA worked on a number of translation projects, several of which are presented here. He was the translator of Karl Sapper's Verapaz im 16. und 17. jahrhundert, which appeared as The Verapaz in the Sixteenth and Seventeenth Centuries: A Contribution to the Historical Geography and Ethnography of Northeastern Guatemala (Los Angeles, University of California, Institute of Archae­ology, Occasional Paper 13, 1985. The contributors to the volume's narrative include, in addtion to Beaudry-Corbett and Hardy, nine other anthropologists who are recognized experts on the region and subject matter.

  1. Upper mantle seismic velocity anomaly beneath southern Taiwan as revealed by teleseismic relative arrival times

    Science.gov (United States)

    Chen, Po-Fei; Huang, Bor-Shouh; Chiao, Ling-Yun

    2011-01-01

    Probing the lateral heterogeneity of the upper mantle seismic velocity structure beneath southern and central Taiwan is critical to understanding the local tectonics and orogeny. A linear broadband array that transects southern Taiwan, together with carefully selected teleseismic sources with the right azimuth provides useful constraints. They are capable of differentiating the lateral heterogeneity along the profile with systematic coverage of ray paths. We implement a scheme based on the genetic algorithm to simultaneously determine the relative delayed times of the teleseismic first arrivals of array data. The resulting patterns of the delayed times systematically vary as a function of the incident angle. Ray tracing attributes the observed variations to a high velocity anomaly dipping east in the mantle beneath the southeast of Taiwan. Combining the ray tracing analysis and a pseudo-spectral method to solve the 2-D wave propagations, we determine the extent of the anomaly that best fits the observations via the forward grid search. The east-dipping fast anomaly in the upper mantle beneath the southeast of Taiwan agrees with the results from several previous studies and indicates that the nature of the local ongoing arc-continent collision is likely characterized by the thin-skinned style.

  2. Centennial and Extreme Climate Variability in the Last 1500 Year from the Belize Central Shelf Lagoon (Central America): Successive Droughts and Floods Linked to the Demise of the Mayan Civilization

    Science.gov (United States)

    Droxler, A. W.; Agar Cetin, A.; Bentley, S. J.

    2014-12-01

    This study focuses on the last 1500 yr precipitation record archived in the mixed carbonate/siliciclastic sediments accumulated in the Belize Central Shelf Lagoon, part of the Yucatan Peninsula eastern continental margin, proximal to the land areas where the Mayan Civilization thrived and then abruptly collapsed. This study is mainly based upon the detailed analyses of cores, BZE-RH-SVC-58 and 68, retrieved in 30 and 19 m of water depth from Elbow Caye Lagoon and English Caye Channel, respectively. The core timeframe is well-constrained by AMS radiocarbon dating of benthic foraminifera, Quinqueloculina. Carbonate content was determined by carbonate bomb, particle size fractions with a Malvern Master Sizer 2000 particle size analyzer, and element (Ti, Si, K, Fe, Al, Ca, and Sr) counts via X-Ray Fluorescence (XRF). The variations of elements such as Ti and K counts, and Ti/Al in these two cores have recorded, in the past past 1500 years, the weathering rate variations of the adjacent Maya Mountain, defining alternating periods of high precipitation and droughts, linked to large climate fluctuations and extreme events, highly influenced by the ITCZ latitudinal migration. The CE 800-900 century just preceding the Medieval Climate Anomaly (MCA), characterized by unusually low Ti counts and Ti/Al, is interpreted to represent a time of low precipitation and resulting severe droughts in the Yucatan Peninsula, contemporaneous with the Mayan Terminal Classic Collapse. High Ti counts and Ti/Al, although highly variable, during the MCA (CE 900-1350) are interpreted as an unusually warm period characterized by two 100-to-250 years-long intervals of higher precipitation when the number of tropical cyclones peaked. These two intervals of high precipitation during the MCA are separated by a century (CE 1000 -1100) of severe droughts and low tropical storm frequency coinciding with the collapse of Chichen Itza (CE 1040-1100). The Little Ice Age (CE 1350-1850), several centuries

  3. Erosion from Above and from Beneath

    DEFF Research Database (Denmark)

    Kjær, Poul F.

    The turn to governance, as unfolded over the last decades, implied a turn to informality, hybridity of public and private and soft law. Taking a long term perspective, this paper highlight that there is nothing new about these features as they also were a central element of earlier corporatist se...

  4. Crustal structure beneath Portugal from teleseismic Rayleigh Wave Ellipticity

    Science.gov (United States)

    Attanayake, Januka; Ferreira, Ana M. G.; Berbellini, Andrea; Morelli, Andrea

    2017-08-01

    Up until now, Portugal lacked a countrywide shear velocity model sampling short length-scale crustal structure, which limits interpretations of seismicity and tectonics, and predictions of strong ground motion. In turn, such interpretations and predictions are important to help mitigate risk of destruction from future large on- and offshore earthquakes similar to those that Portugal has experienced in the past (e.g. the Mw 8.5-8.7 tsunamigenic event in 1755). In this study, we measured teleseismic Rayleigh Wave Ellipticity (RWE) from 33 permanent and temporary seismic stations in Portugal with wave periods between 15 s and 60 s, and inverted it for 1-D models of shear wave velocity (Vs) structure beneath each station using a fully non-linear Monte Carlo method. Because RWE is strongly sensitive to the uppermost few kilometres of the crust, both RWE measurements and Vs models are spatially correlated with surface geology in Portugal. For instance, we find that sedimentary basins produced by rifting that had begun in the Mesozoic such as the Lusitanian Basin (LB) and the Lower Tagus-Sado Basin (LTSB) are characterised by higher RWE (lower Vs). Interestingly, we observe similar RWE (and Vs) values in the interior of the Central Iberian Zone (CIZ), which is a metamorphic belt of Paleozoic age. Together with reduced crustal thickness previously estimated for the same parts of the CIZ, this suggests that the CIZ might have experienced an episode of extension possibly simultaneous to Mesozoic rifting. The Galicia-Tras-os-Montes-Zone (GTMZ) that has undergone polyphased deformation since the Paleozoic is characterised by the lowest RWE (highest Vs) in Portugal. Ossa Morena Zone and the South Portuguese Zone exhibit intermediate Vs values when compared to that of basins and the GTMZ. Our crustal Vs model can be used to provide new insights into the tectonics, seismicity and strong ground motion in Portugal.

  5. La geopolítica de México en Centro América: ¿una hegemonía regional? Mexico's geopolitics in Central America: regional hegemony?

    Directory of Open Access Journals (Sweden)

    Alberto Rocha

    2006-12-01

    analizar el Mecanismo de Diálogo y Concertación de Tuxtla-Gutiérrez y sus tres ámbitos de operación: 1. El ámbito político. 2. El ámbito del desarrollo. 3. El ámbito de la cooperación técnica regional. 4. El ámbito económico, comercial y financiero.Mexico as well as Brazil (first decade of 2000 started to release geo-economic and geo-political projections about their unmediated surroundings (their region of belonging and their mediated surroundings (their neighboring region, besides playing major political roles in their far surroundings (the Latin American and Caribbean region and their remote surroundings (the American continent. As a result, we have proposed and developed the idea that such situations and realities are those of processes of constitution of States with "sub-hegemonic" roles, with their respective functions of "sub-hegemony". We therefore ask the following question: Why are both Mexico and Brazil defining "sub-hegemonic" roles? Are such roles and functions possible within a continental space where a "superpower" exerts unquestionable "supremacy" besides seeking to redefine its "hegemony" (the one now undergoing a crisis? In order to work on the theme of Mexico's geopolitical relations with Central America, we have carried out four approximations: Mexico's current stance; historical background of the relations; process of institutionalization of cooperation; and field of action of the relations. Besides, the work is concluded with some ideas about Mexico's geopolitical view. The approximation to Mexico's structural stance in the world and in the American Continent seeks to highlight realities in its condition of semiperipheral and "sub-hegemonic" country. The historical approximation leads to the 1980s and the 1990s, when the background for Mexico's cooperation with Central America is established and that cooperation is started and strengthened. The institutional approximation, focused on the 1990s and the early 2000s, approaches the field of

  6. New views on American colonization: critical tests from South America

    OpenAIRE

    O'Rourke, Dennis

    2007-01-01

    The traditional view of colonization of the Americas as a migration across Beringia and subsequent dispersal southward following the last glacial maximum is being increasingly questioned. In North America, archaeological links to Siberia are tenuous and genetic data are more consistent with an earlier entry of people into the Americas, from Central rather than Northeast Siberia. An entry of populations into the Americas prior to the last glacial maximum forces a reconsideration not only of ti...

  7. First record of giant anteater (xenarthra, myrmecophagidae) in north america.

    Science.gov (United States)

    Shaw, C A; McDonald, H G

    1987-04-10

    A right metacarpal III represents the first North American record of the giant anteater (Myrmecophaga tridactyla). Recovered in northwestern Sonora, Mexico, with a rich vertebrate fauna of early Pleistocene (Irvingtonian) age, it belongs to a cohort of large mammals that dispersed from South America to North America along a savanna corridor. Presumably habitat and climatic changes have subsequently driven this mammalian family more than 3000 kilometers back into Central America from its former expansion into temperate North America.

  8. Russia Foreign Policy In Latin America - Case Study Of Nicaragua

    Science.gov (United States)

    2017-05-23

    RUSSIA FOREIGN POLICY IN LATIN AMERICA — CASE STUDY OF NICARAGUA A thesis presented to the Faculty of the U.S. Army Command and...MAY 2017 4. TITLE AND SUBTITLE Russia Foreign Policy In Latin America — Case Study Of Nicaragua 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...open arctic channel in the North and in reviving diplomatic contacts and military exercises in Latin America. In Central America specifically, Russia

  9. Insurgency and Counterinsurgency in Central America

    Science.gov (United States)

    1983-06-01

    some time ago. But the sheer brutality of the Guatemalan regime is another insurgent asset: poverty, neglect and then repression politicized the...of the insurgent right lies in their ability to sow sheer terror. Thay can enforce complicity, in a limited fashion at least. Beyond this, however...Rossi, Ernest E. and Piano , Jack C. The Latin American Political Dictionary. Santa Barbara, Calif., 1980. Ryan, John Morris, et. al. Area Handbook

  10. Crustal structure beneath discovery bank in the South Scotia Sea from group velocity tomography and seismic reflection data

    International Nuclear Information System (INIS)

    Vuan, A.; Lodolo, E.; Panza, G.F.

    2003-09-01

    Bruce, Discovery, Herdman and Jane Banks, all located along the central-eastern part of the South Scotia Ridge (i.e., the Antarctica-Scotia plate boundary), represent isolated topographic reliefs surrounded by relatively young oceanic crust, whose petrological and structural nature is still the subject of speculations due to the lack of resolving data. In the Scotia Sea and surrounding regions negative anomalies of about 34% are reported in large-scale group velocity tomography maps. The spatial resolution (∼500 km) of these maps does not warrant any reliable interpretation of such anomalies. A recent surface wave tomography in the same area, performed using broad band seismic stations and 300 regional events, shows that in the period range from 15 s to 50 s the central-eastern part of the South Scotia Ridge is characterized by negative anomalies of the group velocities as large as 6. The resolution of our data set (∼300 km) makes it possible to distinguish an area (centered at 61 deg S and 36 deg W) with a crust thicker than 25 km, and a shear wave velocity vs. depth profile similar to that found beneath the northern tip of the Antarctic Peninsula and southern South America. Rayleigh and Love wave dispersion curves are inverted in the period range from 15 s to 80 s to obtain shear wave velocity profiles that suggest a continental nature of Discovery Bank. The continental-type crust of this topographic relief is in agreement with the interpretation of a multi-channel seismic reflection profile acquired across this rise. Peculiar acoustic facies are observed in this profile and are interpreted as thinned and faulted continental plateau. The boundaries of the negative group velocity anomalies are marked by a high seismicity rate. Historical normal faulting earthquakes with magnitude around 7 are localised between the low velocity anomaly region in the eastern South Scotia Ridge and the high velocity anomaly region associated with the surrounding oceanic crust

  11. Erosion from Above and from Beneath

    DEFF Research Database (Denmark)

    Kjær, Poul F.

    The turn to governance, as unfolded over the last decades, implied a turn to informality, hybridity of public and private and soft law. Taking a long term perspective, this paper highlight that there is nothing new about these features as they also were a central element of earlier corporatist set......-ups at the national as well as the European level. Both corporatism and governance have however ended in profound crises in both functional and legitimacy terms....

  12. Major disruption of D'' beneath Alaska: D'' Beneath Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Daoyuan [Laboratory of Seismology and Physics of Earth' s Interior, School of Earth and Space Sciences, University of Science and Technology of China, Hefei Anhui China; National Geophysics Observatory at Mengcheng, Anhui China; Helmberger, Don [Seismological Laboratory, California Institute of Technology, Caltech, Pasadena California USA; Miller, Meghan S. [Department of Earth Sciences, University of Southern California, Los Angeles California USA; Jackson, Jennifer M. [Seismological Laboratory, California Institute of Technology, Caltech, Pasadena California USA

    2016-05-01

    D'' represents one of the most dramatic thermal and compositional layers within our planet. In particular, global tomographic models display relatively fast patches at the base of the mantle along the circum-Pacific which are generally attributed to slab debris. Such distinct patches interact with the bridgmanite (Br) to post-bridgmanite (PBr) phase boundary to generate particularly strong heterogeneity at their edges. Most seismic observations for the D'' come from the lower mantle S wave triplication (Scd). Here we exploit the USArray waveform data to examine one of these sharp transitions in structure beneath Alaska. From west to east beneath Alaska, we observed three different characteristics in D'': (1) the western region with a strong Scd, requiring a sharp δVs = 2.5% increase; (2) the middle region with no clear Scd phases, indicating a lack of D'' (or thin Br-PBr layer); and (3) the eastern region with strong Scd phase, requiring a gradient increase in δVs. To explain such strong lateral variation in the velocity structure, chemical variations must be involved. We suggest that the western region represents relatively normal mantle. In contrast, the eastern region is influenced by a relic slab that has subducted down to the lowermost mantle. In the middle region, we infer an upwelling structure that disrupts the Br-PBr phase boundary. Such an interpretation is based upon a distinct pattern of travel time delays, waveform distortions, and amplitude patterns that reveal a circular-shaped anomaly about 5° across which can be modeled synthetically as a plume-like structure rising about 400 km high with a shear velocity reduction of ~5%, similar to geodynamic modeling predictions of upwellings.

  13. El género Hydrophilus (Coleoptera: Hydrophilidae: Hydrophilina en México y Centroamérica The genus Hydrophilus (Coleoptera: Hydrophilidae: Hydrophilina in Mexico and Central America

    Directory of Open Access Journals (Sweden)

    Roberto Arce-Pérez

    2013-03-01

    Full Text Available A partir de la revisión morfológica de 499 ejemplares adultos y datos bibliográficos se actualizó la identidad y la distribución precisa de las especies del género Hydrophilus Geoffroy, 1762 que habitan en México y Centroamérica. Se presenta a H. (Dibolocelus purpuracens Régimbart, 1901 como nuevo registro para México. Las especies más ampliamente distribuidas son H. (H. ensifer Brullé, 1837 en 5 países y las Antillas e H. (H. insularis Castelnau, 1840 en 4 países y las Antillas. Los países con mayor riqueza fueron México con 5 especies, y Nicaragua y Costa Rica con 3 especies. En México el estado con mayor riqueza es Veracruz, y en Nicaragua los departamentos de León y Río San Juan. Se presenta una clave ilustrada para el reconocimiento de las especies.The taxonomy and precise distribution of the species of the genus Hydrophilus Geoffroy, 1762 from Mexico and Central America are reviewed, based on the morphological study of499 adult specimens, descriptions and literature records. Hydrophilus (Dibolocelus purpuracens Régimbart, 1901 is recorded for the first time for Mexico. Species with widest distribution are H. (H. ensifer Brullé, 1837 cited from 5 countries and in the Antilles, and H. (H. insularis Castelnau, 1840 cited from 4 countries and the Antilles. The richest countries are Mexico with 5 species, and Costa Rica and Nicaragua with 3 species. The highest species richness is recorded for the state of Veracruz, Mexico, and from the departments of León and Río San Juan, Nicaragua. An illustrated key to the species is included.

  14. Nature and extent of lava-flow aquifers beneath Pahute Mesa, Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Prothro, L.B.; Drellack, S.L. Jr.

    1997-09-01

    Work is currently underway within the Underground Test Area subproject of the US Department of Energy/Nevada Operations Office Environmental Restoration Program to develop corrective action plans in support of the overall corrective action strategy for the Nevada Test Site as established in the Federal Facility Agreement and Consent Order (FFACO, 1996). A closure plan is currently being developed for Pahute Mesa, which has been identified in the FFACO as consisting of the Western and Central Pahute Mesa Corrective Action Units. Part of this effort requires that hydrogeologic data be compiled for inclusion in a regional model that will be used to predict a contaminant boundary for these Corrective Action Units. Hydrogeologic maps have been prepared for use in the model to define the nature and extent of aquifers and confining units that might influence the flow of contaminated groundwater from underground nuclear tests conducted at Pahute Mesa. Much of the groundwater flow beneath Pahute Mesa occurs within lava-flow aquifers. An understanding of the distribution and hydraulic character of these important hydrogeologic units is necessary to accurately model groundwater flow beneath Pahute Mesa. This report summarizes the results of a study by Bechtel Nevada geologists to better define the hydrogeology of lava-flow aquifers at Pahute Mesa. The purpose of this study was twofold: (1) aid in the development of the hydrostratigraphic framework for Pahute Mesa, and (2) provide information on the distribution and hydraulic character of lava-flow aquifers beneath Pahute Mesa for more accurate computer modeling of the Western and Central Pahute Mesa Corrective Action Units.

  15. Crustal Thickness Along the Central American Volcanic Front

    Science.gov (United States)

    MacKenzie, L. S.; Abers, G. A.; Rondenay, S.; Fischer, K. M.; Syracuse, E. M.; Protti, J. M.; Gonzalez, V.; Strauch, W.

    2007-12-01

    Subduction zone processes alter the upper plate in a number of ways, including accretion, magmatic addition, serpentinization of the mantle wedge and formation of mafic cumulates in the lower crust. All of these changes affect seismic velocities, and characterizing the structure of underlying terranes in Central America establishes a baseline for composition and continental growth. Tomography Under Costa Rica and Nicaragua (TUCAN) is a PASSCAL deployment of broadband seismometers over an 18-month period. The network has two dense cross arc lines and two along arc lines that cross terrane boundaries. Teleseismic P and PP arrivals recorded on the TUCAN network have been used to estimate crustal thickness and Vp/Vs, and to develop receiver function images. Surface reflected mode conversions (Ppms and Psms) enhance resolution. Crustal thickness ranges from 25 to 44 km with formal errors ranging 1.6-9.2 km. The thinnest crust (24.6 +/- 3.5 km) lies directly beneath the arc in Nicaragua, whereas the thickest crust (43.5 +/- 2.5 km) lies in the backarc in Nicaragua and beneath the Costa Rican arc (37.9 +/- 5.2). Changes in crustal thickness and Vp/Vs show two distinct terrane boundaries crossing the arc. Vp/Vs indicate continental crust (Vp/Vs=1.71-1.77) in Nicaragua, with a transition to gabbroic crust (Vp/Vs=1.82-1.88) in Costa Rica where fragments of the Caribbean large Igneous Province have been found. Crustal thickness beneath the arc in Costa Rica yields a crustal growth rate of 16-36 km3/km/Ma, assuming a base crustal thickness of 30-32 km with 6-14 Ma of magmatism. The Moho shows strong velocity contrasts throughout the study area, and is the only interface seen in the backarc, but it is complicated by interferences caused by shallow structure beneath the arc and forearc. Forward modeling indicates that reverberations in sediment layers interfere with the Ps arrival, however surface reflected arrivals (Ppms) require a velocity contrast on the order of 0.5-1.0 km

  16. The PACARDO research project: youthful drug involvement in Central America and the Dominican Republic Proyecto de investigación PACARDO: el consumo de drogas entre la juventud en Centroamérica y la República Dominicana

    Directory of Open Access Journals (Sweden)

    Catherine M. Dormitzer

    2004-06-01

    Full Text Available OBJECTIVE: To estimate the occurrence and school-level clustering of drug involvement among school-attending adolescent youths in each of seven countries in Latin America, drawing upon evidence from the PACARDO research project, a multinational collaborative epidemiological research study. METHODS: During 1999-2000, anonymous self-administered questionnaires on drug involvement and related behaviors were administered to a cross-sectional, nationally representative sample that included a total of 12 797 students in the following seven countries: Costa Rica (n= 1 702, the Dominican Republic (n= 2 023, El Salvador (n= 1 628, Guatemala (n= 2 530, Honduras (n= 1 752, Nicaragua (n= 1 419, and Panama (n= 1 743. (The PACARDO name concatenates PA for Panamá,CA for Centroamérica,and RDO for República Dominicana. Estimates for exposure opportunity and actual use of alcohol, tobacco, inhalants, marijuana, cocaine (crack/coca paste, amphetamines and methamphetamines, tranquilizers, ecstasy, and heroin were assessed via responses about questions on age of first chance to try each drug, and first use. Logistic regression models accounting for the complex survey design were used to estimate the associations of interest. RESULTS: Cumulative occurrence estimates for alcohol, tobacco, inhalants, marijuana, and illegal drug use for the overall sample were, respectively: 52%, 29%, 5%, 4%, and 5%. In comparison to females, males were more likely to use alcohol, tobacco, inhalants, marijuana, and illegal drugs; the odds ratio estimates were 1.3, 2.1, 1.6, 4.1, and 3.2, respectively. School-level clustering was noted in all countries for alcohol and tobacco use; it was also noted in Costa Rica, El Salvador, Guatemala, and Panama for illegal drug use. CONCLUSIONS: This report sheds new light on adolescent drug experiences in Panama, the five Spanish-heritage countries of Central America, and the Dominican Republic, and presents the first estimates of school

  17. Ps receiver function imaging of crustal structure and Moho topography beneath the Northeast Caribbean

    Science.gov (United States)

    Ntuli, G.; Agrawal, M.; Pulliam, J.; Huerfano Moreno, V. A.; Polanco Rivera, E.

    2015-12-01

    , with the Moho generally shallower in the east, deepening in central and western Dominican Republic, and shallowing again in the southwest, although values beneath Haiti are poorly constrained. The interpretation of the images places constraints on the structure of the subsurface and may elucidate the causes and styles of deformation occurring in the region.

  18. America's challenge.

    Science.gov (United States)

    Lindsay, G N

    1968-01-01

    As government increasingly recognizes its own obligations to support and provide family planning as a health and social measure, serious questions are raised as to the proper role for Planned Parenthood World Federation as a private organization. Federal programs both at home and abroad tend to make private fundraising more difficult, whatever the role of this organization may be. Contrary to common impression, experience thus far indicates that the existence of governmental programs does not decrease demands on Planned Parenthood as a private agency. A wide gap also exists between public acceptance, which has been realized, and public conviction, which still has not been accepted. Only those who feel distress at the vision of an all-encompassing megalopolis, only those with concern for the qualify of life in the crowd, and only those who see finite limits of resources recognize that the US must someday plan a halt to population growth. As the gap between the developed and the underdeveloped world widens, economists point out that the US, with less than 6% of the world's population, already consumes some 50% of the world's available raw materials. Business and government leaders are beginning to understand the rate at which an industrial and affluent society consumes the world's substance and threatens the environment. If the assumption is correct that the population explosion constitutes a major threat to life on earth, then America's own attitudes and actions at home, as well as abroad and in the developing countries, are vital. In the next few years Planned Parenthood faces the task of converting the tide of public acceptance into one of conviction and effective action on a giant scale both at home and abroad. In its effort, Planned Parenthood has continued to expand its own service functions. It now has 157 local affiliates with an additional 30 in the organizational stage. In 1967 Planned Parenthood affiliates operated 470 family planning centers, 71 more than

  19. Morphological Indicators of a Mascon Beneath Ceres's Largest Crater, Kerwan

    Science.gov (United States)

    Bland, M. T.; Ermakov, A. I.; Raymond, C. A.; Williams, D. A.; Bowling, T. J.; Preusker, F.; Park, R. S.; Marchi, S.; Castillo-Rogez, J. C.; Fu, R. R.; Russell, C. T.

    2018-02-01

    Gravity data of Ceres returned by the National Aeronautics and Space Administration's Dawn spacecraft is consistent with a lower density crust of variable thickness overlying a higher density mantle. Crustal thickness variations can affect the long-term, postimpact modification of impact craters on Ceres. Here we show that the unusual morphology of the 280 km diameter crater Kerwan may result from viscous relaxation in an outer layer that thins substantially beneath the crater floor. We propose that such a structure is consistent with either impact-induced uplift of the high-density mantle beneath the crater or from volatile loss during the impact event. In either case, the subsurface structure inferred from the crater morphology is superisostatic, and the mass excess would result in a positive Bouguer anomaly beneath the crater, consistent with the highest-degree gravity data from Dawn. Ceres joins the Moon, Mars, and Mercury in having basin-associated gravity anomalies, although their origin may differ substantially.

  20. Mapping the mantle transition zone beneath Hawaii from Ps receiver functions: Evidence for a hot plume and cold mantle downwellings

    Science.gov (United States)

    Agius, Matthew R.; Rychert, Catherine A.; Harmon, Nicholas; Laske, Gabi

    2017-09-01

    Hawaii is the archetypal example of hotspot volcanism. Classic plume theory suggests a vertical plume ascent from the core-mantle boundary to the surface. However, recently it has been suggested that the plume path may be more complex. Determining the exact trajectory of the Hawaiian plume seismic anomaly in the mantle has proven challenging. We determine P-to-S (Ps) receiver functions to illuminate the 410- and 660-km depth mantle discontinuities beneath the Hawaiian Islands using waveforms recorded on land and ocean-bottom seismometers, applying new corrections for tilt and coherence to the ocean bottom data. Our 3-D depth-migrated maps provide enhanced lateral resolution of the mantle transition zone discontinuities. The 410 discontinuity is characterised by a deepened area beneath central Hawaii, surrounded by an elevated shoulder. At the 660 discontinuity, shallow topography is located to the north and far south of the islands, and a deep topographic anomaly is located far west and east. The transition zone thickness varies laterally by ±13 km depth: thin beneath north-central Hawaii and thick farther away in a horseshoe-like feature. We infer that at 660-km depth a broad or possibly a double region of upwelling converges into a single plume beneath central Hawaii at 410-km depth. As the plume rises farther, uppermost mantle melting and flow results in the downwelling of cold material, down to at least 410 km surrounding the plume stem. This result in the context of others supports complex plume dynamics including a possible non-vertical plume path and adjacent mantle downwellings.

  1. Borders and Borderlands in the Americas

    Science.gov (United States)

    2012-08-01

    both licit and illicit networks. Traditional territorial security concerns declined in the Americas following the end of the Cold War, and NAFTA in...Central America, and the Caribbean in the 1980s into the United States and Mexico in the last decade. This dynamic has fostered substantial illicit...deepen economic ties and liberalize regimes, privileging development over security.12 Similarly, trade, fostered through NAFTA , has shaped and affected

  2. Simulation of Wave-Plus-Current Scour beneath Submarine Pipelines

    DEFF Research Database (Denmark)

    Eltard-Larsen, Bjarke; Fuhrman, David R.; Sumer, B. Mutlu

    2016-01-01

    A fully coupled hydrodynamic and morphologic numerical model was utilized for the simulation of wave-plus-current scour beneath submarine pipelines. The model was based on incompressible Reynolds-averaged Navier–Stokes equations, coupled with k-ω turbulence closure, with additional bed and suspen......A fully coupled hydrodynamic and morphologic numerical model was utilized for the simulation of wave-plus-current scour beneath submarine pipelines. The model was based on incompressible Reynolds-averaged Navier–Stokes equations, coupled with k-ω turbulence closure, with additional bed...

  3. The upper-mantle transition zone beneath the Chile-Argentina flat subduction zone

    Science.gov (United States)

    Bagdo, Paula; Bonatto, Luciana; Badi, Gabriela; Piromallo, Claudia

    2016-04-01

    The main objective of the present work is the study of the upper mantle structure of the western margin of South America (between 26°S and 36°S) within an area known as the Chile-Argentina flat subduction zone. For this purpose, we use teleseismic records from temporary broad band seismic stations that resulted from different seismic experiments carried out in South America. This area is characterized by on-going orogenic processes and complex subduction history that have profoundly affected the underlying mantle structure. The detection and characterization of the upper mantle seismic discontinuities are useful to understand subduction processes and the dynamics of mantle convection; this is due to the fact that they mark changes in mantle composition or phase changes in mantle minerals that respond differently to the disturbances caused by mantle convection. The discontinuities at a depth of 410 km and 660 km, generally associated to phase changes in olivine, vary in width and depth as a result of compositional and temperature anomalies. As a consequence, these discontinuities are an essential tool to study the thermal and compositional structure of the mantle. Here, we analyze the upper-mantle transition zone discontinuities at a depth of 410 km and 660 km as seen from Pds seismic phases beneath the Argentina-Chile flat subduction.

  4. Shear wave anisotropy beneath the Sierra Nevada range: Implications for lithospheric foundering and upper mantle flow

    Science.gov (United States)

    Badger, N. B.; Bastow, I. D.; Owens, T. J.; Zandt, G.; Jones, C. H.; Gilbert, H.

    2007-12-01

    Recent work asserts that the garnet-rich Sierra Nevada batholith root has undergone foundering since the early Cenozoic. The Sierra Nevada EarthScope Project (SNEP), undertaken to gain a better understanding of this phenomena, consists of a network of ~80 broadband seismometers spaced at ~25 km from ~37.0N to 40.5N. We use the Silver and Chan method to determine shear wave splitting parameters (dt and φ) for teleseismic SKS phases recorded at SNEP and US Array Transportable Array stations in the region. We find dt>1.1s and φ approximately in the E-NE direction over most of the batholith. Splitting of this magnitude cannot be accounted for solely in the crust, and our results, therefore, have significant implications for upper mantle flow beneath the region. At latitude ~39N to 40N, from the western Sierra Nevada range across our study area to central Nevada, we observe dtGorda-Juan de Fuca Plate. Such a flow pattern is also consistent with the circular pattern of splitting measurements that exist in the broader California and Western Nevada region. We observe subtle variations in splitting parameters as a function of backazimuth primarily at stations situated on the western foothills of the Sierra Nevada. These complexities may be indicative of either a two-layer or dipping layer structure beneath the batholith that may be associated with on- going lithospheric foundering beneath the Sierran range. Additionally, in the southern part of our study area, we note a reduction in dt for arrivals that sample the high Vp Isabella anomaly - an upper mantle downwelling thought to be a result of recent lithospheric foundering.

  5. Lithospheric and sublithospheric anisotropy beneath the Baltic shield from surface-wave array analysis

    Science.gov (United States)

    Pedersen, Helle A.; Bruneton, Marianne; Maupin, Valérie; Svekalapko Seismic Tomography Working Group

    2006-04-01

    We report measurements of radial and azimuthal anisotropy in the upper mantle beneath southern and central Finland, which we obtained by array analysis of fundamental-mode Rayleigh and Love waves. Azimuthally averaged phase velocities were analysed in the period range 15 to 190 s for Rayleigh waves and 15 to 100 s for Love waves. The azimuthal variation of the Rayleigh wave phase velocities was obtained in the period range 20 to 100 s. The limited depth resolution of fundamental-mode surface waves necessitated strong damping constraints in the inversion for anisotropic parameters. We investigated the effects of non-unicity on the final model by experimenting with varying model geometries. The radial anisotropy beneath Finland can be explained by a lithosphere at least 200 km thick, predominantly (> 50% by volume) composed of olivine crystals having their a-axes randomly distributed in the horizontal plane. On the contrary, the measured lithospheric azimuthal anisotropy is small. This can be reconciled with body-wave observations made in the area that indicate a complex pattern of rapidly varying anisotropy. Below 200-250 km depth, that is below the petrologic lithosphere as revealed by xenolith analyses conducted in the area, the magnitude of the azimuthal anisotropy increases and would be compatible with a mantle containing 15-20% by volume of olivine crystals whose a-axes are coherently aligned in the N-NE direction. The alignment of the a-axes is off the direction of present-day absolute plate motion in either the no-net-rotation or hot-spot reference frame, currently N55-N60. We interpret this mismatch as evidence for a complex convective flow pattern of the mantle beneath the shield, which, by inference, is decoupled from the overlying lithosphere.

  6. Three-Dimensional Crustal Architecture Beneath the Sikkim Himalaya and Its Relationship to Active Deformation

    Science.gov (United States)

    Paul, Himangshu; Mitra, Supriyo

    2017-10-01

    We study the 3-D variation of the crustal structure of the Sikkim Himalaya using broadband seismological data acquired from a focused network of seven stations spanning the Lesser, Higher, and Tethyan Himalaya. Common conversion point stacking of receiver functions recorded along an across-strike profile of the Himalaya reveals first-order northward dip on the Main Himalayan Thrust (MHT), a midcrustal discontinuity and the Moho, along with higher-order lateral variations. Three-dimensional images generated from joint inversion of receiver functions and surface wave dispersions show that the MHT has a ramp-flat-ramp geometry. The ramps are located beneath the Lesser Himalaya and the Tethyan Himalaya with dips of ˜7∘ and ˜15∘, respectively, connected by flat segments. The ramp beneath the Lesser Himalaya forms a dome structure, upwarping the thrust sheets associated with the Peling and Main Central Thrust. The erosional surface of this dome forms the arcuate geometry of thrusts observed in the Lesser Himalaya. The thickness of the underthrust Indian crust is 35-42 km and has an average VS of 3.63 km/s, similar to that of the Indian Shield crust. The Moho also has dome-like structures separated by elongated, deeper sections trending NW-SE. These are intersected by steeply dipping transverse low-velocity zones, oblique to the strike of the Himalaya. We conjecture that these low-velocity zones are the dextral-strike slip faults known to be active beneath the Sikkim Himalaya. The observed alternate shallow and deep segments of the Moho must be a consequence of several cycles of strike-slip displacement on these transverse faults.

  7. Deep long-period earthquakes beneath Washington and Oregon volcanoes

    Science.gov (United States)

    Nichols, M.L.; Malone, S.D.; Moran, S.C.; Thelen, W.A.; Vidale, J.E.

    2011-01-01

    Deep long-period (DLP) earthquakes are an enigmatic type of seismicity occurring near or beneath volcanoes. They are commonly associated with the presence of magma, and found in some cases to correlate with eruptive activity. To more thoroughly understand and characterize DLP occurrence near volcanoes in Washington and Oregon, we systematically searched the Pacific Northwest Seismic Network (PNSN) triggered earthquake catalog for DLPs occurring between 1980 (when PNSN began collecting digital data) and October 2009. Through our analysis we identified 60 DLPs beneath six Cascade volcanic centers. No DLPs were associated with volcanic activity, including the 1980-1986 and 2004-2008 eruptions at Mount St. Helens. More than half of the events occurred near Mount Baker, where the background flux of magmatic gases is greatest among Washington and Oregon volcanoes. The six volcanoes with DLPs (counts in parentheses) are Mount Baker (31), Glacier Peak (9), Mount Rainier (9), Mount St. Helens (9), Three Sisters (1), and Crater Lake (1). No DLPs were identified beneath Mount Adams, Mount Hood, Mount Jefferson, or Newberry Volcano, although (except at Hood) that may be due in part to poorer network coverage. In cases where the DLPs do not occur directly beneath the volcanic edifice, the locations coincide with large structural faults that extend into the deep crust. Our observations suggest the occurrence of DLPs in these areas could represent fluid and/or magma transport along pre-existing tectonic structures in the middle crust. ?? 2010 Elsevier B.V.

  8. The upper mantle beneath the Philippine Sea from waveform inversions

    NARCIS (Netherlands)

    Lebedev, Sergei; Nolet, Guust; Hilst, R.D. van der

    1997-01-01

    We present a three‐dimensional S‐velocity model for the upper mantle beneath the Philippine Sea region. It was derived from inversions of 281 broad band vertical‐component seismograms recorded in the area at the Global Seismological Network (GSN) and SKIPPY portable array stations. We have been able

  9. Project Skippy explores the lithosphere and mantle beneath Australia

    NARCIS (Netherlands)

    Hilst, R.D. van der; Kennett, Brian; Christie, Doug; Grant, John

    1994-01-01

    A new project is probing the seismic structure of the lithosphere and mantle beneath Australia. The Skippy Project, named after the bush kangaroo, exploits Australia's regional seismicity and makes use of recent advances in digital recording technology to collect three-component broadband

  10. Living and Working Beneath the Sea – Next Approach

    Directory of Open Access Journals (Sweden)

    Rowiński Lech

    2017-04-01

    Full Text Available The idea of living beneath the sea is very new if compared with millennia of shipping activity. In fact, ocean surface was considered mainly as medium suitable for transport of persons and goods as well as aggression and robbery. More practical attempts to live “on” the water surface are limited to well protected internal waters.

  11. Slab detachment of subducted Indo-Australian plate beneath Sunda ...

    Indian Academy of Sciences (India)

    ... complicate the subduction zone processes and slab architecture. Based on evidences which include patterns of seismicity, seismic tomography and geochemistry of arc volcanoes, we have identified a horizontal slab tear in the subducted Indo-Australian slab beneath the Sunda arc. It strongly reflects on trench migration, ...

  12. Anomalous electric field changes and high flash rate beneath a ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 119; Issue 5. Anomalous electric field changes and high flash rate beneath a thunderstorm in northeast India ... Further,all electric field changes after a lightning discharge indicates the presence of strong Lower Positive Charge Centers (LPCC)in the active and ...

  13. Three-dimensional shallow velocity structure beneath Taal Volcano, Philippines

    Science.gov (United States)

    You, Shuei-Huei; Konstantinou, Konstantinos I.; Gung, Yuancheng; Lin, Cheng-Horng

    2017-11-01

    Based on its numerous historical explosive eruptions and high potential hazards to nearby population of millions, Taal Volcano is one of the most dangerous "Decade Volcanoes" in the world. To provide better investigation on local seismicity and seismic structure beneath Taal Volcano, we deployed a temporary seismic network consisting of eight stations from March 2008 to March 2010. In the preliminary data processing stage, three periods showing linear time-drifting of internal clock were clearly identified from noise-derived empirical Green's functions. The time-drifting errors were corrected prior to further data analyses. By using VELEST, 2274 local earthquakes were manually picked and located. Two major earthquake groups are noticed, with one lying beneath the western shore of Taal Lake showing a linear feature, and the other spreading around the eastern flank of Taal Volcano Island at shallower depths. We performed seismic tomography to image the 3D structure beneath Taal Volcano using the LOTOS algorithm. Some interesting features are revealed from the tomographic results, including a solidified magma conduit below the northwestern corner of Taal Volcano Island, indicated by high Vp, Vs, and low Vp/Vs ratio, and a large potential hydrothermal reservoir beneath the center of Taal Volcano Island, suggested by low Vs and high Vp/Vs ratio. Furthermore, combining earthquake distributions and tomographic images, we suggest potential existence of a hydrothermal reservoir beneath the southwestern corner of Taal Lake, and a fluid conduit extending to the northwest. These seismic features have never been proposed in previous studies, implying that new hydrothermal activity might be formed in places away from the historical craters on Taal Volcano Island.

  14. Geochronology, geochemistry and tectonic evolution of the Western and Central cordilleras of Colombia

    Science.gov (United States)

    Villagómez, Diego; Spikings, Richard; Magna, Tomas; Kammer, Andreas; Winkler, Wilfried; Beltrán, Alejandro

    2011-08-01

    Autochthonous rocks of the pre-Cretaceous continental margin of NW South America (the Tahami Terrane) are juxtaposed against a series of para-autochthonous rock units that assembled during the Early Cretaceous. Allochthonous, oceanic crust of the Caribbean Large Igneous Province collided with and accreted onto the margin during the Late Cretaceous. We present the first regional-scale dataset of zircon U-Pb LA-ICP-MS ages for intrusive and metamorphic rocks of the autochthonous Tahami Terrane, Early Cretaceous igneous para-autochthonous rocks and accreted oceanic crust. The U-Pb zircon data are complemented by multiphase 40Ar/ 39Ar crystallization and cooling ages. The geochronological data are combined with whole rock major oxide, trace element and REE data acquired from the same units to constrain the tectonic origin of the rock units and terranes exposed in the Western Cordillera, Cauca-Patía Valley and the Central Cordillera of Colombia. The Tahami Terrane includes lower Paleozoic orthogneisses (~ 440 Ma) that may have erupted during the active margin stage of the Rheic Ocean. Basement gneisses were intruded by Permian, continental arc granites during the final assembly of Pangea. Triassic sedimentary rocks were subsequently deposited in rift basins and partially melted during high-T metamorphism associated with rifting of western Pangea during 240-220 Ma. Continental arc magmatism during 180-145 Ma is preserved along the whole length of the Central Cordillera and was followed by an Early Cretaceous out-board step of the arc axis and the inception of the Quebradagrande Arc that fringed the continental margin. Back-stepping of the arc axis may have been caused by the collision of buoyant seamounts, which were coeval with plateau rocks exposed in the Nicoya Peninsular of Costa Rica. Rapid westward drift of South America closed the Quebradagrande basin in the late Aptian and caused medium-high P-T metamorphic rocks of the Arquía Complex to exhume and obduct onto

  15. Mantle upwelling beneath Madagascar: evidence from receiver function analysis and shear wave splitting

    Science.gov (United States)

    Paul, Jonathan D.; Eakin, Caroline M.

    2017-07-01

    Crustal receiver functions have been calculated from 128 events for two three-component broadband seismomenters located on the south coast (FOMA) and in the central High Plateaux (ABPO) of Madagascar. For each station, crustal thickness and V p / V s ratio were estimated from H- κ plots. Self-consistent receiver functions from a smaller back-azimuthal range were then selected, stacked and inverted to determine shear wave velocity structure as a function of depth. These results were corroborated by guided forward modeling and by Monte Carlo error analysis. The crust is found to be thinner (39 ± 0.7 km) beneath the highland center of Madagascar compared to the coast (44 ± 1.6 km), which is the opposite of what would be expected for crustal isostasy, suggesting that present-day long wavelength topography is maintained, at least in part, dynamically. This inference of dynamic support is corroborated by shear wave splitting analyses at the same stations, which produce an overwhelming majority of null results (>96 %), as expected for vertical mantle flow or asthenospheric upwelling beneath the island. These findings suggest a sub-plate origin for dynamic support.

  16. Moessbauer spectroscopic study of corrosion products beneath primer coating containing anticorrosive pigments

    International Nuclear Information System (INIS)

    Kumar, A.V.R.; Nigam, R.K.

    1998-01-01

    The phase analysis of the rusts generated beneath the primer containing micaceous iron oxide (MIO) and micaceous iron oxide in combination with red lead (RL), zinc phosphate (ZP), basic lead silicochromate (BLSC) and zinc chromate (ZC) has been carried out by Moessbauer spectroscopy at room temperature. The rust beneath the coating obtained after immersion of the painted panel for six months in 3% NaCl, consists mainly of non-stoichiometric magnetite together with small fractions of γ-, α-FeOOH except in the case of panel painted with RL containing MIO showed only a central doublet indicating the formation of γ-FeOOH and SPM α-FeOOH. Non-stoichiometry of magnetite as calculated from the ratio of B/A sites of the peaks of magnetite in the spectrum has been found depending on the nature of anticorrosive pigment present in the primer coating. The order of non-stoichiometry has been found to be in order of ZC > BLSC > ZP > MIO. (author)

  17. Imaging D" Beneath Mexico Using American P Wave Data

    Science.gov (United States)

    Hutko, A.; Revenaugh, J.

    2003-12-01

    Broadband data from North American permanent and temporary stations recording events 20-60 degrees away in Central America and northern South America are used to study the lower mantle by analyzing PcP, ScP and their precursors (topside reflections and back-scattered arrivals ). The lowermost few hundred km of the mantle, D", is physically and chemically more heterogeneous than the overlying bulk of the mantle and contains wavespeed variations rivaling those of the crust. Core-reflected and mid and lower mantle scattered P and S waves are typically low energy phases and some form of stacking is necessary to raise their signal-to-noise ratios to levels suitable for modeling and interpretation. We use two methods. Where data is limited, we bin data according to their reflection point on the CMB, and then perform simple 1D time-to-depth analysis of PcP (or ScP) precursors. P is used as a reference phase in order to reduce the travel time variations caused by upper mantle and crustal velocity heterogeneity. All data are source-normalized by deconvolution of a source-time function calculated from the data. Using this method, we hope to constrain ˜ 100 km variations in the height and strength of a D" reflector recognized regionally in earlier studies using stacks of short-period data. We will atempt to better characterize the strength and thickness of ultra low velocity zones found in this region in previous studies. In areas of greater data density, we will also use a stochastic migration method patterned after the Kirchhof Regional Migration method of Revenaugh (2000). This approach to migration offers greater immunity to artifacts than simple diffraction stacking, but offers similar resolution of scatterers and specular reflectors. Preliminary results reveal several bright reflections whose depth and strength change significantly between bins suggesting that the D" layer in this region is quite complex at scale lengths as small as one to two hundred km. The data also

  18. Drought-induced recharge promotes long-term storage of porewater salinity beneath a prairie wetland

    Science.gov (United States)

    Levy, Zeno F.; Rosenberry, Donald O.; Moucha, Robert; Mushet, David M.; Goldhaber, Martin B.; LaBaugh, James W.; Fiorentino, Anthony J.; Siegel, Donald I.

    2018-02-01

    Subsurface storage of sulfate salts allows closed-basin wetlands in the semiarid Prairie Pothole Region (PPR) of North America to maintain moderate surface water salinity (total dissolved solids [TDS] from 1 to 10 g L-1), which provides critical habitat for communities of aquatic biota. However, it is unclear how the salinity of wetland ponds will respond to a recent shift in mid-continental climate to wetter conditions. To understand better the mechanisms that control surface-subsurface salinity exchanges during regional dry-wet climate cycles, we made a detailed geoelectrical study of a closed-basin prairie wetland (P1 in the Cottonwood Lake Study Area, North Dakota) that is currently experiencing record wet conditions. We found saline lenses of sulfate-rich porewater (TDS > 10 g L-1) contained in fine-grained wetland sediments 2-4 m beneath the bathymetric low of the wetland and within the currently ponded area along the shoreline of a prior pond stand (c. 1983). During the most recent drought (1988-1993), the wetland switched from a groundwater discharge to recharge function, allowing salts dissolved in surface runoff to move into wetland sediments beneath the bathymetric low of the basin. However, groundwater levels during this time did not decline to the elevation of the saline lenses, suggesting these features formed during more extended paleo-droughts and are stable in the subsurface on at least centennial timescales. We hypothesize a "drought-induced recharge" mechanism that allows wetland ponds to maintain moderate salinity under semiarid climate. Discharge of drought-derived saline groundwater has the potential to increase the salinity of wetland ponds during wet climate.

  19. Seismic structure of the lithosphere beneath NW Namibia: Impact of the Tristan da Cunha mantle plume

    Science.gov (United States)

    Yuan, Xiaohui; Heit, Benjamin; Brune, Sascha; Steinberger, Bernhard; Geissler, Wolfram H.; Jokat, Wilfried; Weber, Michael

    2017-01-01

    Northwestern Namibia, at the landfall of the Walvis Ridge, was affected by the Tristan da Cunha mantle plume during continental rupture between Africa and South America, as evidenced by the presence of the Etendeka continental flood basalts. Here we use data from a passive-source seismological network to investigate the upper mantle structure and to elucidate the Cretaceous mantle plume-lithosphere interaction. Receiver functions reveal an interface associated with a negative velocity contrast within the lithosphere at an average depth of 80 km. We interpret this interface as the relic of the lithosphere-asthenosphere boundary (LAB) formed during the Mesozoic by interaction of the Tristan da Cunha plume head with the pre-existing lithosphere. The velocity contrast might be explained by stagnated and "frozen" melts beneath an intensively depleted and dehydrated peridotitic mantle. The present-day LAB is poorly visible with converted waves, indicating a gradual impedance contrast. Beneath much of the study area, converted phases of the 410 and 660 km mantle transition zone discontinuities arrive 1.5 s earlier than in the landward plume-unaffected continental interior, suggesting high velocities in the upper mantle caused by a thick lithosphere. This indicates that after lithospheric thinning during continental breakup, the lithosphere has increased in thickness during the last 132 Myr. Thermal cooling of the continental lithosphere alone cannot produce the lithospheric thickness required here. We propose that the remnant plume material, which has a higher seismic velocity than the ambient mantle due to melt depletion and dehydration, significantly contributed to the thickening of the mantle lithosphere.

  20. Togetherness in the Americas.

    Science.gov (United States)

    Black, Jan Knippers

    1984-01-01

    There is a growing unacknowledged reality to the oneness of America. Latin America is increasingly sharing not only the blessings of U.S.-style modernization, but its demons as well. Also, many problems that have long plagued Latin America, e.g., indebtedness and militarism, are becoming more apparent in the United States. (RM)

  1. Slab Contributions to Cascades Magmas: Constraints from Central Oregon and Northern California

    Science.gov (United States)

    Ruscitto, D. M.; Wallace, P. J.

    2010-12-01

    The Cascades arc is the global end member, warm-slab subduction zone (slab thermal parameter ~200 km) resulting from the slow subduction of young oceanic crust beneath North America. Significant slab dehydration is predicted to occur beneath the forearc (e., H2O, S, Cl) beneath the forearc should result in reduced slab contributions to the mantle wedge, consistent with muted subduction-related signatures in calc-alkaline magmas and low magmatic volatile flux estimates from Oregon and Washington compared to other arcs (e.g., Marianas, Kamchatka, Central America). Despite reduced slab-derived inputs, olivine-hosted melt inclusions in the Central Oregon Cascades display elevated volatile contents in melts erupted along the volcanic front compared to those erupted towards the back-arc. In contrast to Oregon and Southern Washington, primitive magmas from the southern part of the arc (e.g., Mt. Shasta) contain some of the highest H2O contents reported. We used olivine-hosted melt inclusion data from Central Oregon and Northern California to estimate the input of volatiles and trace elements from the slab to the mantle wedge beneath the Cascades. Inclusions from near Mt. Shasta in Northern California represent two types of hydrous primitive melts that have equilibrated with a refractory mantle: high-Mg andesite (HMA) and primitive basaltic andesite (PBA) with 3.3 and 5.6 wt.% H2Omax, respectively. Three distinct primitive melt compositions were calculated using inclusions from Central Oregon: calc-alkaline basalt, Sr-rich basalt, and depleted basaltic andesite (1.6, 2.3, and 3.0 wt.% H2Omax, respectively). We calculated extents of mantle melting for each primitive magma composition using Ti, Y, Gd, Dy, Er, and Yb contents (i.e., assuming negligible contributions from the slab). Based on these calculations, we infer Central Oregon and Shasta magmas to represent 8-15% and 14-20% partial melts (respectively) of variably depleted sources. Major elements in preliminary slab

  2. Central American Climatology

    Science.gov (United States)

    1985-04-01

    Central America, as where mean temperatures are relatively warm throughout the year de- so spite seasonal rainfall changes. 75 Elevation, solar angle...November 1982 Control Hidalgo Anos.1952-1963, Republica de Nicaragua, Ministerio de Formento Y O0.PP, Comision Nacional de Energia . Craig, Richard A., The

  3. Finite frequency tomography of D″ shear velocity heterogeneity beneath the Caribbean

    Science.gov (United States)

    Hung, Shu-Huei; Garnero, Edward J.; Chiao, Ling-Yun; Kuo, Ban-Yuan; Lay, Thorne

    2005-07-01

    The shear velocity structure in the lowermost 500 km of the mantle beneath the Caribbean and surrounding areas is determined by seismic tomography applied to a suite of Sd-SKS, ScS-S, (Scd + Sbc)-S, and ScS-(Scd + Sbc) differential times, where (Scd + Sbc) is a pair of overlapping triplication arrivals produced by shear wave interaction with an abrupt velocity increase at the top of the D″ region. The inclusion of the triplication arrivals in the inversion, a first for a deep mantle tomographic model, is possible because of the widespread presence of a D″ velocity discontinuity in the region. The improved ray path sampling provided by the triplication arrivals yields improved vertical resolution of velocity heterogeneity within and above the D″ region. The reference velocity model, taken from a prior study of waveforms in the region, has a 2.9% shear velocity discontinuity 250 km above the core-mantle boundary (CMB). Effects of aspherical structure in the mantle at shallower depths than the inversion volume are suppressed by applying corrections for several different long-wavelength shear velocity tomography models. Born-Fréchet kernels are used to characterize how the finite frequency data sample the structure for all of the differential arrival time combinations; inversions are performed with and without the kernels. The use of three-dimensional kernels stabilizes the tomographic inversion relative to a ray theory parameterization, and a final model with 60- and 50-km correlation lengths in the lateral and radial dimensions, respectively, is retrieved. The resolution of the model is higher than that of prior inversions, with 3-4% velocity fluctuations being resolved within what is commonly described as a circum-Pacific ring of high velocities. A broad zone of relatively high shear velocity material extends throughout the lower mantle volume beneath the Gulf of Mexico, with several percent lower shear velocities being found beneath northern South America

  4. Finite-Frequency Tomography of D'' Shear Velocity Heterogeneity beneath the Caribbean

    Science.gov (United States)

    Hung, S.; Garnero, E. J.; Chiao, L.; Kuo, B.; Lay, T.

    2004-12-01

    The shear velocity structure in the lowermost 500 km of the mantle beneath the Caribbean and surrounding areas is determined by seismic tomography applied to a suite of Sdiff-SKS, ScS-S, (Scd+Sbc)-S, and ScS-(Scd+Sbc) differential times, where (Scd+Sbc) is a pair of overlapping triplication arrivals produced by shear wave interaction with an abrupt velocity increase at the top of the D'' region. The inclusion of the triplication arrivals in the inversion, a first for a deep mantle tomographic model, is possible because of the widespread presence of a D'' velocity discontinuity in the region. The additional raypath sampling provided by the triplication arrivals yields improved vertical resolution of velocity heterogeneity within and above the D'' region. The reference velocity model, taken from a prior study of waveforms in the region, has a 2.9% shear velocity discontinuity 250 km above the CMB. Effects of aspherical structure in the mantle at shallower depths than the inversion volume are suppressed by applying corrections for several different long-wavelength shear velocity tomography models. Born-Fréchet kernels are used to characterize how the finite-frequency data sample the structure for all of the differential arrival time combinations; inversions are performed with and without the kernels. The use of 3-D kernels stabilizes the tomographic inversion relative to a ray theory parameterization, and a final model with 60 and 50 km correlation lengths in the the lateral and radial dimensions, respectively, is retrieved. The resolution of the model is higher than that of prior inversions, with 3 to 4% velocity fluctuations being resolved within what is commonly described as a circum-Pacific ring of high velocities. A broad zone of relatively high shear velocity material extends throughout the lower mantle volume beneath the Gulf of Mexico, with several percent lower shear velocities being found beneath northern South America. Concentrated low velocity regions

  5. Development of food crops by modern biotechnology techniques in Central America Desarrollo de cultivos y alimentos por técnicas de biotecnología moderna en Centroamérica

    Directory of Open Access Journals (Sweden)

    Giovanni Garro Monge

    2012-12-01

    Full Text Available In the last decade, the adoption of Genetically Modified Crops (GMC has increased in stages worldwide. The worldwide total area planted with biotech crops reached 148 million hectares by 2010, also increasing the number of farmers around the world who decided to produce crops with this technology. At the regional level there are different responses of government agencies by generating rules and regu- lations according to the reality of these countries. In Central America, countries with greater partici- pation in the development and cultivation of food biotechnology techniques are Guatemala (papa- ya, Honduras (beans and maize and Costa Rica (cotton, soybean and pineapple, placing the latter two in the 29 countries with more GMO planting crops worldwide in 2010. Some of the countries of the region have implemented governance structures for the regulation through technical committees on Biosafety. The most important characteristics in terms of trade continue to be those that confer herbicide tolerance or pest resistance. But notice the incur- sion of new products that contain changes in their content, which are emerging as an alternative with great perspectives in the region. These experiences of culture and Biosafety regula- tion at the regional level could be a successful and progressive development of agricultural and food biotechnology in the near future.En la última década, la adopción de Cultivos Genéticamente Modificados (CGM se ha incre- mentado de forma escalonada a nivel mundial. El área sembrada con cultivos biotecnológicos llegó a un total de 148 millones de hectáreas en 2010, aumentando también el número de agricultores que decidieron producir este tipo de cultivos. A nivel regional, se producen respuestas diversas de los órganos gubernamentales mediante reglamen- tos y normativas acordes con la realidad local. En Centroamérica, los países con mayor participación en el desarrollo y cultivo de alimentos utilizando t

  6. Establishment of a new genus for Parastenocaris itica (Copepoda, Harpacticoida from El Salvador, Central America, with discussion of the Parastenocaris fontinalis and P. proserpina groups Proposta de um novo gênero para Parastenocaris itica (Copepoda, Harpacticoida de El Salvador, América Central e discussão dos grupos Parastenocaris fontinalis e P. proserpina

    Directory of Open Access Journals (Sweden)

    Paulo Henrique C. Corgosinho

    2012-01-01

    Full Text Available A new genus of Parastenocarididae is described from the Neotropical region. Iticocaris gen. nov. is established to include Parastenocaris itica Noodt, 1962. Iticocaris gen. nov. is defined by the following characters: 1 male leg 3 with 2-segmented exopod; 2 first exopodal segment short and rectangular; 3 thumb hypertrophic, longer than the second exopodal segment and inserted on the distal edge of exopod segment 1, occupying the whole distal margin; 4 exopod 2 or apophysis strongly sclerotized, articulated with the exopod segment 1 on its inner margin and curved against the thumb, forming a strong forceps; 5 leg 4 endopod without dimorphism in shape and size vs. minor dimorphism in ornamentation; 6 leg 5 with three setae and 7 lack of the anterolateral furcal seta II. The new genus is monotypic, represented by Iticocaris itica (Noodt, 1962 comb. nov., from El Salvador, Central America. A close relationship is hypothesized between I. itica and the genus Brasilibathynellocaris Jakobi, 1972, the males of which both share the forceps-like elongated apophysis.Um novo gênero de Parastenocarididae é proposto para a Região Neotropical para incluir Parastenocaris itica Noodt, 1962. Iticocaris gen. nov. é diagnosticado pela presença dos seguintes caracteres: 1 toracópodo 3 do macho com exópodo bissegmentado; 2 primeiro segmento exopodal curto e retangular; 3 "thumb" hipertrófico, mais longo que o segundo segmento do exópodo e inserido na margem distal do exópodo 1, ocupando toda a margem distal do segmento; 4 exópodo 2 ou apófise fortemente esclerotizado, articulado com o exópodo 1 em sua margem interna e curvado contra o "thumb", formando um forte fórceps; 5 endópodo do toracópodo 4 sem dimorfismo sexual quanto à forma e tamanho vs. discreto dimorfismo quanto à ornamentação; 6 toracópodo 5 com três cerdas e 7 furca sem a cerda anterolateral II. O novo gênero é monotípico, sendo representado por Iticocaris itica (Noodt, 1962 comb

  7. Korean Investments in Latin America: Current Status and Prospects

    Directory of Open Access Journals (Sweden)

    Taik-Hwan Jyoung

    1998-06-01

    Full Text Available This thesis first took an overall look at the relationship between Asia and Central and South America. Meanwhile, this thesis studied the growth potential of these two continents and the rapid growth trend compared with other areas. Based on these, this thesis emphasized the necessity of the cooperation between Asia and Central and South America, which has been alienated for a long period. Upon studying of this thesis, the reader will track the connection of the overseas investment strategy of Korea to the domestic and overseas economic factors while analyzing its motivation and feature, etc. Also, it analyzes Korea's future investment in Central and South America as comparing with the strategies of Japan and Taiwan. Besides, in this thesis the author is trying to get future-oriented experiences from the analyses in areas such as trade, investment experience, culture difference and personnel exchange, and the prospect of the relationship between Korea and Central and South America. This thesis brought forward the 'blueprint' about promoting the cooperation between Asia and Central and South America, such as to organize the meeting for the new setting summit conference of Asian and Central American leaders, to add members from Central and South America countries to the MERCOSUR of APEC, to expand items in order to promote mutual-communication.

  8. Kelvin-Helmholtz wave generation beneath hovercraft skirts

    Science.gov (United States)

    Sullivan, P. A.; Walsh, C.; Hinchey, M. J.

    1993-05-01

    When a hovercraft is hovering over water, the air flow beneath its skirts can interact with the water surface and generate waves. These, in turn, can cause the hovercraft to undergo violent self-excited heave motions. This note shows that the wave generation is due to the classical Kelvin-Helmholtz mechanism where, beyond a certain air flow rate, small waves at the air water interface extract energy from the air stream and grow.

  9. Slow upper mantle beneath Southern Norway from surface waves

    Science.gov (United States)

    Weidle, C.; Maupin, V.

    2009-04-01

    A recent regional surface wave tomography for Northern Europe revealed unprecedented images of the upper mantle beneath the (Tertiary) North Atlantic and the bordering Fennoscandian craton of Archean-Proterozoic age. With respect to the circum-Atlantic regions of uplift, no common mantle pattern supporting the uplift of these regions is observed. The western boundary of the thick cratonic lithosphere follows the trend of the continental margin offshore northern Norway (i.e. the northern Scandes are underlain by thick lithosphere) whereas further south the boundary of the craton is located further east beneath southwestern Sweden. SV shear wave velocities beneath southern Norway are 10% slower than ak135 (at 70-115 km depth) and these low-velocities are clearly connected to the North Atlantic low-velocity regime through a ~ 400 km wide "channel". The low-velocity anomaly beneath Southern Norway coincides in geometry roughly with the dome-like high topography of the southern Scandes and may thus have a non-negligible contribution to the isostatic balance of the region. The amplitude and depth-distribution of this anomaly are due to be further constrained by new data that were acquired during the MAGNUS experiment in 2006-2008. The temporary seismic network, consisting of 40 broadband seismometers covers to a large extent the location of the anomaly as imaged by the regional tomography. This enables us to get unique control on the tomographic model at improved lateral and vertical resolution. Preliminary analysis of surface wave phase velocities yields an average 1-D shear wave velocity profile for southern Norway as a first step to constrain the presence and depth extent of this low-velocity anomaly.

  10. Crawling beneath the free surface: Water snail locomotion

    OpenAIRE

    Lee, Sungyon; Bush, John W. M.; Hosoi, A. E.; Lauga, Eric

    2008-01-01

    Land snails move via adhesive locomotion. Through muscular contraction and expansion of their foot, they transmit waves of shear stress through a thin layer of mucus onto a solid substrate. Since a free surface cannot support shear stress, adhesive locomotion is not a viable propulsion mechanism for water snails that travel inverted beneath the free surface. Nevertheless, the motion of the freshwater snail, Sorbeoconcha physidae, is reminiscent of that of its terrestrial counterparts, being g...

  11. The extent of continental crust beneath the Seychelles

    Science.gov (United States)

    Hammond, J. O. S.; Kendall, J.-M.; Collier, J. S.; Rümpker, G.

    2013-11-01

    The granitic islands of the Seychelles Plateau have long been recognised to overlie continental crust, isolated from Madagascar and India during the formation of the Indian Ocean. However, to date the extent of continental crust beneath the Seychelles region remains unknown. This is particularly true beneath the Mascarene Basin between the Seychelles Plateau and Madagascar and beneath the Amirante Arc. Constraining the size and shape of the Seychelles continental fragment is needed for accurate plate reconstructions of the breakup of Gondwana and has implications for the processes of continental breakup in general. Here we present new estimates of crustal thickness and VP/VS from H-κ stacking of receiver functions from a year long deployment of seismic stations across the Seychelles covering the topographic plateau, the Amirante Ridge and the northern Mascarene Basin. These results, combined with gravity modelling of historical ship track data, confirm that continental crust is present beneath the Seychelles Plateau. This is ˜30-33 km thick, but with a relatively high velocity lower crustal layer. This layer thins southwards from ˜10 km to ˜1 km over a distance of ˜50 km, which is consistent with the Seychelles being at the edge of the Deccan plume prior to its separation from India. In contrast, the majority of the Seychelles Islands away from the topographic plateau show no direct evidence for continental crust. The exception to this is the island of Desroche on the northern Amirante Ridge, where thicker low density crust, consistent with a block of continental material is present. We suggest that the northern Amirantes are likely continental in nature and that small fragments of continental material are a common feature of plume affected continental breakup.

  12. On Irrotational Flows Beneath Periodic Traveling Equatorial Waves

    Science.gov (United States)

    Quirchmayr, Ronald

    2017-06-01

    We discuss some aspects of the velocity field and particle trajectories beneath periodic traveling equatorial surface waves over a flat bed in a flow with uniform underlying currents. The system under study consists of the governing equations for equatorial ocean waves within a non-inertial frame of reference, where Euler's equation of motion has to be suitably adjusted, in order to account for the influence of the earth's rotation.

  13. Educational Research in Latin America: A Twelve-Year Perspective.

    Science.gov (United States)

    Egginton, Everett

    1983-01-01

    Analyzes reviewers' assessments of all publications on Latin American education included in the "Handbook of Latin American Studies" since 1969. Compares publications on education in South America with those relating to Central America and the Caribbean. Concludes that although the quality of research has been uneven, progress is being…

  14. Latin America in World Geography Textbooks for the Secondary School.

    Science.gov (United States)

    Andereck, Mary E.; Dixon, Clifton V., Jr.

    The purpose of this study was to quantitatively analyze the Latin American content of contemporary world geography textbooks published for United States secondary schools. A preliminary review of the literature indicated that Latin America was generally omitted from world geography texts, Central America was given minimal attention, and…

  15. Latin America: An Annotated List of Materials for Children.

    Science.gov (United States)

    United Nations Children's Fund, New York, NY. United States Committee.

    This annotated bibliography of materials on Latin America is intended for children to age 14. South and Central America, Mexico, and the French, English, and Spanish speaking areas of the Caribbean are covered. Listings are by country and include history books, geography books, fiction, nonfiction, poetry, and folklore books. Some works in Spanish…

  16. Immigration and the New Racial Diversity in Rural America

    Science.gov (United States)

    Lichter, Daniel T.

    2012-01-01

    This article highlights the new racial and ethnic diversity in rural America, which may be the most important but least anticipated population shift in recent demographic history. Ethnoracial change is central to virtually every aspect of rural America over the foreseeable future: agro-food systems, community life, labor force change, economic…

  17. Rights and Justice and the Social Web Movement (Latin America ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Duration. 24 months. IDRC Officer. Smith, Matthew. Total funding. CA$ 482,841. Country(s). North and Central America, South America. Project Leader. Carlos Gregorio. Project Leader. Carlos Gregorio. Institution. Instituto de Investigación para la Justicia - Asociación Civil. Institution Country. Argentina. Institution Website.

  18. Dermatobia hominis myiasis among travelers returning from South America.

    Science.gov (United States)

    Tamir, Jeremy; Haik, Josef; Orenstein, Arie; Schwartz, Eli

    2003-04-01

    Dermatobia hominis is the most common cause of myiasis in Central and South America, affecting mammals and humans, causing nonhealing furuncle-like lesions. During the years 1994 to 1999, 14 Israeli travelers returning from South America were diagnosed with D hominis myiasis. The approach consists of correct diagnosis and a proper removal of the larvae, after which the patients heal with no complications.

  19. Supporting E-government in Latin America and the Caribbean ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC Officer. Smith, Matthew. Total funding. CA$ 850,300. Country(s). North and Central America, South America, West Indies. Project Leader. Miguel Porrúa. Institution. General Secretariat of the Organization of American States. Institution Country. United States. Institution Website. http://www.oas.org. Outputs. Reports.

  20. Elia Kazan's America America: A Message for America.

    Science.gov (United States)

    Molofsky, Merle

    2018-03-26

    Elia Kazan's 1963 film, America America is a tribute to the immigrant experience of his own forebears, and has relevance to the refugee crisis of today. In stark black and white cinematography, the film provides insight into the refugee-immigrant experience, personified in Stavros, a young man longing for freedom, obsessed with an idealized America. His hope and innocence cannot safeguard him. His memories of his happy childhood and loving family create idealizing transferences to a world of others who manipulate and betray him as he undertakes his quest. Eventually he too learns to manipulate and betray, unconsciously identifying with the aggressor. History will offer ethical challenges, the black and white cinematography mirroring the black and white perception of good and bad, the shades of grey evoking a maturation of understanding.

  1. Crustal structure beneath the southern Korean Peninsula from local earthquakes

    Science.gov (United States)

    Kim, Kwang-Hee; Park, Jung-Ho; Park, Yongcheol; Hao, Tian-Yao; Kim, Han-Joon

    2017-05-01

    The 3-D subsurface structure beneath the southern Korean Peninsula is poorly known, even though such information could be key in verifying or rejecting several competing models of the tectonic evolution of East Asia. We constructed a 3-D velocity model of the upper crust beneath the southern Korean Peninsula using 19 935 P-wave arrivals from 747 earthquakes recorded by high-density local seismic networks. Results show significant lateral and vertical variations: velocity increases from northwest to southeast at shallow depths, and significant velocity variations are observed across the South Korea Tectonic Line between the Okcheon Fold Belt and the Youngnam Massif. Collision between the North and South China blocks during the Early Cretaceous might have caused extensive deformation and the observed negative velocity anomalies in the region. The results of the tomographic inversion, combined with the findings of previous studies of Bouguer and isostatic gravity anomalies, indicate the presence of high-density material in the upper and middle crust beneath the Gyeongsang Basin in the southeastern Korean Peninsula. Although our results partially support the indentation tectonic model, it is still premature to discard other tectonic evolution models because our study only covers the southern half of the peninsula.

  2. Morphological indicators of a mascon beneath Ceres' largest crater, Kerwan

    Science.gov (United States)

    Bland, Michael T.; Ermakov, Anton; Raymond, Carol A.; Williams, David A.; Bowling, Tim J.; Preusker, F.; Park, Ryan S.; Marchi, Simone; Castillo-Rogez, Julie C.; Fu, R.R.; Russell, Christopher T.

    2018-01-01

    Gravity data of Ceres returned by the National Aeronautics and Space Administration's Dawn spacecraft is consistent with a lower density crust of variable thickness overlying a higher density mantle. Crustal thickness variations can affect the long‐term, postimpact modification of impact craters on Ceres. Here we show that the unusual morphology of the 280 km diameter crater Kerwan may result from viscous relaxation in an outer layer that thins substantially beneath the crater floor. We propose that such a structure is consistent with either impact‐induced uplift of the high‐density mantle beneath the crater or from volatile loss during the impact event. In either case, the subsurface structure inferred from the crater morphology is superisostatic, and the mass excess would result in a positive Bouguer anomaly beneath the crater, consistent with the highest‐degree gravity data from Dawn. Ceres joins the Moon, Mars, and Mercury in having basin‐associated gravity anomalies, although their origin may differ substantially.

  3. Why are there few seedlings beneath the myrmecophyte Triplaris americana?

    Science.gov (United States)

    Larrea-Alcázar, Daniel M.; Simonetti, Javier A.

    2007-07-01

    We compared the relative importance of chemical alellopathy, pruning behaviour of resident ants and other non-related agents to ant-plant mutualism for seedling establishment beneath Triplaris americana L. (Polygonaceae), a myrmecophyte plant. We also included a preliminary analysis of effects of fragmentation on these ecological processes. Seeds and seedlings of Theobroma cacao L. (Sterculiaceae) were used as the target species in all experiments. Leaf-tissue extracts of the myrmecophyte plant did not inhibit germination of cacao seeds. Resident Pseudomyrmex triplarinus Weddell (Pseudomyrmecinae) ants did not remove seeds under the canopy of their host plants. The main seed consumer was the leaf-cutting ant Atta sexdens L. (Myrmicinae). Leaves of cacao seedlings were partially or totally pruned by Pseudomyrmex ants mainly in forest fragments studied. We offer evidence pointing to the possibility that the absence of seedlings beneath Triplaris may result from effects of both ant species. We discuss the benefits of pruning behaviour for the resident ant colony and the effects of ant-ant interactions on seedling establishment beneath this ant-plant system.

  4. The Lithosphere-asthenosphere Boundary beneath the South Island of New Zealand

    Science.gov (United States)

    Hua, J.; Fischer, K. M.; Savage, M. K.

    2017-12-01

    Lithosphere-asthenosphere boundary (LAB) properties beneath the South Island of New Zealand have been imaged by Sp receiver function common-conversion point stacking. In this transpressional boundary between the Australian and Pacific plates, dextral offset on the Alpine fault and convergence have occurred for the past 20 My, with the Alpine fault now bounded by Australian plate subduction to the south and Pacific plate subduction to the north. This study takes advantage of the long-duration and high-density seismometer networks deployed on or near the South Island, especially 29 broadband stations of the New Zealand permanent seismic network (GeoNet). We obtained 24,980 individual receiver functions by extended-time multi-taper deconvolution, mapping to three-dimensional space using a Fresnel zone approximation. Pervasive strong positive Sp phases are observed in the LAB depth range indicated by surface wave tomography (Ball et al., 2015) and geochemical studies. These phases are interpreted as conversions from a velocity decrease across the LAB. In the central South Island, the LAB is observed to be deeper and broader to the west of the Alpine fault. The deeper LAB to the west of the Alpine fault is consistent with oceanic lithosphere attached to the Australian plate that was partially subducted while also translating parallel to the Alpine fault (e.g. Sutherland, 2000). However, models in which the Pacific lithosphere has been underthrust to the west past the Alpine fault cannot be ruled out. Further north, a zone of thin lithosphere with a strong and vertically localized LAB velocity gradient occurs to the west of the fault, juxtaposed against a region of anomalously weak LAB conversions to the east of the fault. This structure, similar to results of Sp imaging beneath the central segment of the San Andreas fault (Ford et al., 2014), also suggests that lithospheric blocks with contrasting LAB properties meet beneath the Alpine fault. The observed variations in

  5. Look Out Below: Islamic Terrorism in South America

    National Research Council Canada - National Science Library

    Cruz, Christopher A

    2006-01-01

    ..., and a sympathetic population filled with anti-American sentiment, the Islamic terrorist threat is very real in South America and should be a major security concern for the United States. While U.S. Central Command (CENTCOM...

  6. Understanding the nature of mantle upwelling beneath East-Africa

    Science.gov (United States)

    Civiero, Chiara; Hammond, James; Goes, Saskia; Ahmed, Abdulhakim; Ayele, Atalay; Doubre, Cecile; Goitom, Berhe; Keir, Derek; Kendall, Mike; Leroy, Sylvie; Ogubazghi, Ghebrebrhan; Rumpker, Georg; Stuart, Graham

    2014-05-01

    The concept of hot upwelling material - otherwise known as mantle plumes - has long been accepted as a possible mechanism to explain hotspots occurring at Earth's surface and it is recognized as a way of removing heat from the deep Earth. Nevertheless, this theory remains controversial since no one has definitively imaged a plume and over the last decades several other potential mechanisms that do not require a deep mantle source have been invoked to explain this phenomenon, for example small-scale convection at rifted margins, meteorite impacts or lithospheric delamination. One of the best locations to study the potential connection between hotspot volcanism at the surface and deep mantle plumes on land is the East African Rift (EAR). We image seismic velocity structure of the mantle below EAR with higher resolution than has been available to date by including seismic data recorded by stations from many regional networks ranging from Saudi Arabia to Tanzania. We use relative travel-time tomography to produce P- velocity models from the surface down into the lower mantle incorporating 9250 ray-paths in our model from 495 events and 402 stations. We add smaller earthquakes (4.5 image structures of ~ 100-km length scales to ~ 1000 km depth beneath the northern East-Africa rift (Ethiopia, Eritrea, Djibouti, Yemen) with good resolution also in the transition zone and uppermost lower mantle. Our observations provide evidence that the shallow mantle slow seismic velocities continue trough the transition zone and into the lower mantle. In particular, the relatively slow velocity anomaly beneath the Afar Depression extends up to depths of at least 1000 km depth while another low-velocity anomaly beneath the Main Ethiopian Rift seems to be present in the upper mantle only. These features in the lower mantle are isolated with a diameter of about 400 km indicating deep multiple sources of upwelling that converge in broader low-velocity bodies along the rift axis at shallow

  7. Behavioral problems and tobacco use among adolescents in Central America and the Dominican Republic Problemas conductuales y consumo de tabaco en adolescentes de Centroamérica y la República Dominicana

    Directory of Open Access Journals (Sweden)

    Kenneth Vittetoe

    2002-02-01

    Full Text Available Objectives. The purpose of this study was to examine the association between behavioral problems and tobacco use among adolescent students in six countries of Central America and in the Dominican Republic. Methods. Data were drawn from a multinational collaborative study that included questionnaire surveys of between 451 and 1 170 school-attending adolescents in each of the seven countries studied. Assessments were based on an adapted, Spanish-language version of the Drug Use Screening Inventory (DUSI. The conditional form of logistic regression was employed for analysis, matching students on type of school and area, with further statistical adjustments for sex, age, and selected risk factors. Results. Occurrence of tobacco use was observed to vary dramatically from country to country. Nonetheless, for the combined group of countries, the estimated odds of tobacco use in youths at the highest levels of behavioral problems was more than five times that for youths at the lowest levels, after controlling for sex, age, lack of participation in recreational activities, level of irritability, and levels of problems with school, family, and mental health. Country- specific analyses show that youths at the highest levels of behavioral problems have a consistently greater occurrence of tobacco use as compared to youths at the lowest levels of behavioral problems. Conclusions. These findings are concordant with prior studies on tobacco use among adolescents with behavioral problems. Although the magnitude of observed associations varied according to the country of residence, the strength of these associations and their significance by conventional standards were observed in nearly all the countries sampled. This is the first study in these seven countries on potentially causal relationships such as these. More research is needed to augment our knowledge regarding the observed cross-country differences and ultimately to develop, implement, and evaluate

  8. How is the Slowdown Affecting Households in Latin America and the Caribbean?

    OpenAIRE

    Calvo-Gonzalez, Oscar; Castaneda, R. Andres; Farfan, Maria Gabriela; Reyes, German; Sousa, Liliana D.

    2017-01-01

    This paper shows evidence that suggests the economic slowdown in Latin America and the Caribbean has already translated into slowing social gains, including decelerating poverty reduction, stagnating growth of the middle class, and lower income growth. The countries of South America outperformed Mexico, Central America, and the Caribbean in poverty reduction during the decade up to 2012. B...

  9. Outline of Education Systems and School Conditions in Latin America. Bulletin, 1923, No. 44

    Science.gov (United States)

    Luckey, George W. A.

    1923-01-01

    This bulletin is divided into two parts: (1) South America; and (2) Mexico, Cuba, and Central America. The countries included under the term "Latin America" are so extensive and important, and the effects of the World War, direct and indirect, on all systems of education have been so disturbing, that one is at a loss to know how best to…

  10. Seismic Velocity Anomalies beneath Tatun Volcano Group, Northern Taiwan

    Science.gov (United States)

    Lin, Tzu-yu; Lin, Cheng-Horng; Yang, Tsanyao Frank; Chang, Li-Chin

    2015-04-01

    Volcanic eruption has been a natural disaster for human society. Taiwan is located in the Pacific Ring of Fire. Although there is no obvious phenomenon of volcanic activity in Taiwan, some volcanoes need to be monitored, especially the Tatun Volcano Group (TVG), which exhibits very active hydrothermal activity, is located on the tip of southwestern Ryukyu arc. TVG is about 15 km north to Taipei, capital of Taiwan, and is nearby two nuclear power plants along the northern coast of Taiwan. If TVG erupts, there must be a serious impact and damage to Taiwan. Since TVG is located within the Yangmingshan National Park, any artificial seismic source is not allowed to estimate possible eruption site and the degree of volcanic disaster. Instead, we use natural seismic waves generated by earthquakes to image the possible velocity anomaly of magma chamber and/or hydrothermal system beneath TVG. We systematically compare the differences of arrival times generated by some local earthquakes and recorded at 42 seismic stations in 2014 for finding any low-velocity zone within the crust. The results show that the arrival times always appeared significant delay at some particular seismic stations, such as Chi-Hsin-Shan (CHS), Siao-You-Keng (SYK) and some other stations at TVG, no matter where the earthquakes occurred. It implies that possible low-velocity zones, which could be the location of magma chamber and/or active hydrothermal system, exist beneath the CHS and SYK areas. This feature is generally consistent with the clustered micro-earthquakes in the shallow crust beneath the CHS area in the last decade.

  11. Evidence for dike emplacement beneath Iliamna Volcano, Alaska in 1996

    Science.gov (United States)

    Roman, D.C.; Power, J.A.; Moran, S.C.; Cashman, K.V.; Doukas, M.P.; Neal, C.A.; Gerlach, T.M.

    2004-01-01

    Two earthquake swarms, comprising 88 and 2833 locatable events, occurred beneath Iliamna Volcano, Alaska, in May and August of 1996. Swarm earthquakes ranged in magnitude from -0.9 to 3.3. Increases in SO2 and CO2 emissions detected during the fall of 1996 were coincident with the second swarm. No other physical changes were observed in or around the volcano during this time period. No eruption occurred, and seismicity and measured gas emissions have remained at background levels since mid-1997. Earthquake hypocenters recorded during the swarms form a cluster in a previously aseismic volume of crust located to the south of Iliamna's summit at a depth of -1 to 4 km below sea level. This cluster is elongated to the NNW-SSE, parallel to the trend of the summit and southern vents at Iliamna and to the regional axis of maximum compressive stress determined through inversion of fault-plane solutions for regional earthquakes. Fault-plane solutions calculated for 24 swarm earthquakes located at the top of the new cluster suggest a heterogeneous stress field acting during the second swarm, characterized by normal faulting and strike-slip faulting with p-axes parallel to the axis of regional maximum compressive stress. The increase in earthquake rates, the appearance of a new seismic volume, and the elevated gas emissions at Iliamna Volcano indicate that new magma intruded beneath the volcano in 1996. The elongation of the 1996-1997 earthquake cluster parallel to the direction of regional maximum compressive stress and the accelerated occurrence of both normal and strike-slip faulting in a small volume of crust at the top of the new seismic volume may be explained by the emplacement and inflation of a subvertical planar dike beneath the summit of Iliamna and its southern satellite vents. ?? 2003 Elsevier B.V. All rights reserved.