Angularella audubonensis sp. n. (Dilepididae) and Other Cestodes of Cliff Swallows in Colorado

One hundred forty-five cliff swallows, Petrochelidon pyrrhonota, were examined for cestodes in two separate surveys in Weld County, Colorado. Seven species representing four genera were found. Angularella audubonensis sp. n. is differentiated by the small size of the rostellar hooks (8.4-13.5 μm) and the medial relationship of the cirrus pouch to the osmoregulatory canals. Other species collected were Angularella beema, Anonchotaenia globata, Mayhewia ababili, Vitta magniuncinata, Vitta parvirostris and Vitta riparia. Seven new hosts and geographic distribution records were established for Colorado, and six new records were determined for North America.

Phytoplankton Dynamics in Three Rocky Mountain Lakes, Colorado, U.S.A.

In 1984 and 1985 seasonal changes in phytoplankton were studied in a system of three lakes in Loch Vale, Rocky Mountain National Park, Colorado. Three periods were evident: (1) A spring bloom, during snowmelt, of the planktonic diatom Asterionella Formosa, (2) a mid- summer period of minimal algal abundance, and (3) a fall bloom of the blue-green alga Oscillatoria limnetica. Seasonal phytoplankton dynamics in these lakes are controlled partially by the rapid flushing rate during snowmelt and the transport of phytoplankton from the highest lake to the lower lakes by the stream, Icy Brook. During snowmelt, the A. formosa population in the most downstream lake has a net rate of increase of 0.34 d-1, which is calculated from the flushing rate and from the A. formosa abundance in the inflow from the upstream lake and in the downstream lake. Measurement of photosynthetic rates at different depths during the three periods confirmed the rapid growth of A. formosa during the spring. The decline in A. formosa after snowmelt may be related to grazing by developing zooplankton populations. The possible importance of the seasonal variations in nitrate concentrations were evaluated in situ enrichment experiments. For A. formosa and O. limnetica populations, growth stimulation resulted from 8- or 16-micromolar amendments of calcium nitrate and sulfuric acid, but the reason for this stimulation could not be determined from these experiments.

Morphology and surface sedimentation on the upper and middle continental slope off Uruguay

This paper presents for the first time a morphological and surface sediment characterization of the Uruguayan outer continental shelf and slope. The study is based on a high-resolution coverage using hydrographical, geomorphological and sedimentological sampling and several textural and productivity proxies. Along slope terraces and an important canyon system characterizes continental slope morphology, indicating that across- and down-slope sedimentary processes control large-scale sedimentation. Terraces represent the prolongation of the Argentinean Contouritic Depositional System that vanishes in the study area, presumably as a result of the dynamic of the Brazil-Malvinas confluence. Canyons incised in the upper slope are likely related to low-stand sea level conditions. At the outer shelf and shallow upper slope (170-250 m depth), off-shelf sand transport is inferred from the distribution of relict sand and reworked biogenic gravel. In the upper continental slope, the northern region is characterized by an erosive environment controlled by a steep slope and the southward flowing Brazil current. In the south, a depositional environment is enhanced by the presence of a gentler slope and seaward incised canyons and is mainly controlled by hemipelagic processes associated with nutrient-rich Sub-Antarctic Waters (SAW), by its confluence with South Atlantic Central Waters (SACW) and by the Rio de la Plata’s (RdlP) influence. Additionally, within the upper slope, the occurrence of igneous-metamorphic cobbles and pebbles in canyon and mound lag deposits suggests the influence of glacial fluvial discharge and/or iceberg transport processes. In the middle slope, sedimentation is controlled by thermohaline-induced deep-water bottom currents. The decreasing influence of the erosive Antarctic Intermediate Water (AAIW) is evident in a northward diminution in grain size. The variety of transport and sedimentary processes identified reflect the control of the Brazil-Malvinas confluence zone and the Rio de la Plata’s discharge.

Evolución Paleoambiental de la Bahia de Montevideo - (Uruguay) Bases para el Estabelecimento de un modelo ambiental

La acción modificadora del hombre como agente geológico deja su rastro en el sedimento permitiendo así el estudiar las transformaciones del ambiente y el registro de los procesos antrópicos. De esta forma, la determinación de cuando ocurrieron los primeros episodios de contaminación antrópica, y la evaluación de la respuesta del sistema a tales eventos constituye una herramienta potencial para fines de manejo. La Bahía de Montevideo está integrada al sector fluvio‐marino del Río de la Plata y la mayoría de su agua proviene de éste. Este sistema ha sufrido grandes presiones antrópicas en los últimos 100‐150 años lo que ha provocado importantes consecuencias negativas sobre el ecosistema. El objetivo del presente trabajo es evaluar el registro histórico, analizando las capas más superficiales de sedimento de un testigo de 200 cm para determinar la historia de los cambios recientes causados por la presión humana en la Bahía de Montevideo. En este sentido fue aplicado un análisis integrado de los parámetros geoquímicos y foraminíferos. Fue posible diferenciar tres zonas en la columna sedimentaria. La zona I definida desde la base del testigo hasta los 110 cm de profundidad está constituida por altos porcentajes de arena, bajas concentraciones de materia orgánica y bajos valores de susceptibilidad magnética. Los foraminíferos estuvieron representados por especies generalistas, calcáreas y mixoalinas tales como A. tepida, A. parkinsoniana, E. excavatum y E. gunteri. La zona II (intervalo 110 y 60 cm) caracterizada por una marcada disminución en el tamaño del sedimento (altos porcentajes de limo y arcilla), alto porcentaje de materia orgánica y aumento en la SM. Los foraminíferos presentaron bajos valores de densidad, diversidad y riqueza. Las especies dominantes fueron Psammosphera sp. y H. wilberti (ambas de paredes aglutinantes, características de ambientes oligohalinos y ricos en materia orgánica). La zona III corresponde a los últimos 100 años. Se observó que los cambios ambientales registrados en la región condujeron a la presencia de altas concentraciones de metales pesados en la columna sedimentaria así como a grandes cambios en la distribución de la fauna de foraminíferos. Los valores máximos de Cr, Cu y Pb en la Zona III son 70, 14 y 12 veces mayores que el valor mínimo registrado para cada metal, respectivamente, en el testigo estudiado. Todos los metales analizados ‐ indicadores de polución ‐ presentan una tendencia al aumento desde la base de la tercera zona hacia el tope del testigo. El factor de enriquecimiento (FE) muestra claramente que todos los metales presentan la misma tendencia de aumento en la tercera zona con un incremento marcado en las camadas superiores de la columna sedimentaria. De acuerdo con los valores del FE el Cr presenta un nivel de polución entre significativo y alto. El Pb y el Zn indicaron ambos polución moderada. El incremento en los vertidos industriales en la región de la Bahía de Montevideo provocó un cambio dramático en las características químicas del sedimento (alrededor de 10‐15 cm, 1983 AD) y consecuentemente en la fauna de foraminíferos (disminución en los valores de diversidad, riqueza y densidad) llevándola a un empobrecimiento con momentos casi azoicos.

Estudio espacio-temporal de los foraminíferos bentônicos en un área altamente impactada: Bahía de Montevideo y región costera adyacente (Uruguay)

Los ambientes marinos y estuarinos estuvieron gradualmente sujetos a impactos significativos durante el siglo XX, debido al incremento en el uso como sumideros de desechos antropogénicos, afectando a las comunidades acuáticas que las habitan. Varios estudios han demostrado que es posible determinar relaciones entre los foraminíferos y condiciones ambientales tanto naturales como antropogénicas. Los foraminíferos bentónicos pueden ser afectados por variables ambientales tales como: concentración de materia orgánica, niveles de oxígeno, cambios en la salinidad y la presencia de metales pesados en el sedimento. Variaciones en estas condiciones pueden influenciar su abundancia y diversidad, y resultar en la deformación de sus caparazones. Como regla general, los foraminíferos que son abundantes y tienen una distribución geográfica amplia son las especies tolerantes a la contaminación. Es el caso de Ammonia tepida, especie eurihalina y oportunista, que ha sido reportada como dominante cerca de efluentes de metales pesados, aguas residuales, efluentes químicos y térmicos, y fertilizantes. Bajo condiciones adversas, algunas especies oportunistas pueden mudar su estrategia reproductiva de sexuada a asexuada, generando organismos menores de ciclo de vida corto con una tasa de reproducción más elevada, por lo que la biometría de los caparazones puede ser una herramienta útil como indicador de tales condiciones.

Decompression during Late Proterozoic Al2SiO5 Triple-Point Metamorphism at Cerro Colorado, New Mexico

An outstanding problem in understanding the late Proterozoic tectonic assembly of the southwest is identifying the tectonic setting associated with regional metamorphism at 1.4 Ga. Both isobaric heating and cooling, and counter-clockwise looping PT paths are proposed for this time. We present a study of the Proterozoic metamorphic and deformation history of the Cerro Colorado area, southern Tusas Mountains, New Mexico, which shows that the metamorphism in this area records near-isothermal decompression from 6 to 4 kbar at ca. 1.4 Ga. We do not see evidence for isobaric heating at this time. Decompression from peak pressures is recorded by the reaction Ms + Grt = St + Bt, with a negative slope in PT space; the reaction Ms + Grt = Sil + Bt, which is nearly horizontal in PT space; and partial to total pseudomorphing of kyanite by sillimanite during the main phase of deformation. The clearest reaction texture indicating decompression near peak metamorphic temperature is the replacement of garnet by clots of sillimanite, which are surrounded by halos of biotite. The sillimanite clots, most without relict garnet in the cores and with highly variable aspect ratios, are aligned. They define a lineation that formed with the dominant foliation. An inverted metamorphic gradient is locally defined by sillimanite-garnet schists (625 degrees C) structurally above staurolite-garnet schists (550 degrees C) and implies ductile thrusting during the main phase of deformation. The exhumation that led to the recorded decompression was likely in response to crustal thickening due to ductile thrusting and subsequent denudation.

Foraminifera from the Colorado Shale of North-Central Montana

The use of foraminifera in the determination of geologic age, and in the correlation of strata, is one of the most important techniques in oil field stratigraphic studies. The petroleum industry in many regions relies on these microscopic life forms to determine the positions of oil-bearing horizons and to determine the tops of beds. In northern Montana the Colorado group of strata, a series of about 2,000 feet of dense, dark similar shales, is known to contain foraminifers.

High exchangeable calcium concentrations in soils on Barro Colorado Island, Panama

The soils on four lithologies (basaltic conglomerates, Bohio; Andesite; volcanoclastic sediments with basaltic agglomerates, Caimito volcanic; foraminiferal limestone, Caimito marine) on Barro Colorado Island (BCI) have high exchangeable Ca concentrations and cation-exchange capacities (CEC) compared to other tropical soils on similar parent material. In the 0–10 cm layer of 24 mineral soils, pH values ranged from 5.7 (Caimito volcanic and Andesite) to 6.5 (Caimito marine), concentrations of exchangeable Ca from 134 mmolc kg− 1 (Caimito volcanic) to 585 mmolc kg− 1 (Caimito marine), and cation exchange capacities from 317 mmolc kg− 1 (Caimito volcanic) to 933 mmolc kg− 1 (Caimito marine). X-ray diffractometry of the fraction < 2 μm revealed that smectites dominated the clay mineral assemblage in soil except on Caimito volcanic, where kaolinite was the dominant clay mineral. Exchangeable Ca concentrations decreased with increasing soil depth except on Caimito marine. The weathering indices Chemical Index of Alteration (CIA), Plagioclase Index of Alteration (PIA) and Weathering Index of Parker (WIP) determined for five soils on all geological formations, suggested that in contrast to expectation the topsoil (0–10 cm) appeared to be the least and the subsoil (50–70 cm) and saprolite (isomorphically weathered rock in the soil matrix) the most weathered. Additionally, the weathering indices indicated depletion of base cations and enrichment of Al-(hydr)oxides throughout the soil profile. Tree species did not have an effect on soil properties. Impeded leaching and the related occurrence of overland flow seem to be important in determining clay mineralogy. Our results suggest that (i) edaphic conditions favor the formation of smectites on most lithologies resulting in high CEC and thus high retention capacity for Ca and (ii) that there is an external source such as dust or sea spray deposition supplying Ca to the soils.

An Assessment of the Case for Monetary Union or Official Dollarization in Argentina, Brazil, Chile, Uruguay and Venezuela

We use a data set covering the whole period of Argentina's currency board and most of that spanned by the Mercosur trade agreement to examine the case for either a Latin American monetary union or monetary union with the USA (through official dollarization). Our econometric evidence using VAR techniques indicates that macroeconomic shocks are still so highly asymmetric in Latin America and between Latin American countries and the USA as to make monetary union or official dollarization somewhat doubtful policies.

Zwei neue Salices aus der Sammlung: "Plants of Southern Colorado collected and distributed by C. F. Baker, F. S. Earle and S. M. Tracy"

Von Otto v. Seemen

Health care policy analysis of Medicaid's early and periodic screening, diagnosis, and treatment (EPSDT) benefit in Colorado

The purpose of this thesis is to identify "best practice" recommendations for successful implementation of the EPSDT outreach program at Memorial Health System's Hospital for Children in Colorado Springs through a policy analysis of Medicaid EPSDT services in Colorado. A successful program at Memorial will increase education and awareness of EPSDT services, enrollment, and access to and utilization of health care services for eligible children. Methodology utilized in this study included questionnaires designed for the EPSDT contract administrator and outreach coordinators/workers; analysis of current federal and state policies; and studies conducted at the federal and state level, and by various advocacy groups. The need for this analysis of EPSDT came about in part through an awareness of increasingly high numbers of children in poverty and who are uninsured. Though the percentage of children living in poverty in Colorado is slightly below the national average (see Table 2), according to data analyzed by The Annie E. Casey Foundation, the percentage of children (0-18) living in poverty in Colorado increased from 10% in 2000 to 16% in 2006, a dramatic increase of 60% surpassed by only one other state in the nation (The Annie E. Casey Foundation, 2008). By comparison, the U.S. percentage of children in poverty during the same time frame rose from 17% to 18% (The Annie E. Casey Foundation, 2008). What kind of health care services are available to this vulnerable and growing group of Coloradans, and what are the barriers that affect their enrollment in, access to and utilization of these health care services? Barriers identified included difficulty with the application process; system and process issues; a lack of providers; and a lack of awareness and knowledge of EPSDT. Fiscal restraints and legislation at the federal and state level are also barriers to increasing enrollment and access to services. Outreach services are a critical component of providing EPSDT services, and there were several recommendations regarding outreach and case management that will benefit the program in the future. Through this analysis and identification of a broad range of barriers, a clearer picture emerged of current challenges within the EPSDT program as well as a broad range of strategies and recommendations to address these challenges. Through increased education and advocacy for EPSDT and the services it encompasses; stronger collaboration and cooperation between all groups involved, including providing a Medical Home for all eligible children; and new legislation putting more money and focus on comprehensive health care for low-income uninsured children; enrollment, access to and utilization of developmentally appropriate and quality health care services can be achieved. ^