The Entrada Sandstone is a formation in the San Rafael Group that is found in the U.S. states of Wyoming, Colorado, northwest New Mexico, northeast Arizona and southeast Utah. Part of the Colorado Plateau, this formation was deposited during the Jurassic period sometime between 180 and 140 million years ago in various environments, including: tidal mudflats, beaches and sand dunes. The Middle Jurassic San Rafael Group was dominantly deposited as ergs in a desert environment around the shallow Sundance Sea. Wikipedia.
Zhu Y.,Texas A&M University |
Chen C.-H.,Texas A&M University |
Wilson Z.,Texas A&M University |
Savukov I.,Entrada |
Hilty C.,Texas A&M University
Journal of Magnetic Resonance | Year: 2016
Hyperpolarization methods offer a unique means of improving low signal strength obtained in low-field NMR. Here, simultaneous measurements of NMR at a field of 0.7 mT and laser optical absorption from samples hyperpolarized by dissolution dynamic nuclear polarization (D-DNP) are reported. The NMR measurement field closely corresponds to a typical field encountered during sample injection in a D-DNP experiment. The optical spectroscopy allows determination of the concentration of the free radical required for DNP. Correlation of radical concentration to NMR measurement of spin polarization and spin-lattice relaxation time allows determination of relaxivity and can be used for optimization of the D-DNP process. Further, the observation of the nuclear Overhauser effect originating from hyperpolarized spins is demonstrated. Signals from 1H and 19F in a mixture of trifluoroethanol and water are detected in a single spectrum, while different atoms of the same type are distinguished by J-coupling patterns. The resulting signal changes of individual peaks are indicative of molecular contact, suggesting a new application area of hyperpolarized low-field NMR for the determination of intermolecular interactions. © 2016 Elsevier Inc.
Niemeyer C.,University of Sao Paulo |
Favero C.M.,University of Sao Paulo |
Kolesnikovas C.K.M.,Entrada |
Bhering R.C.C.,Institute Pesquisa E Reabilitacao Of Animais Marinhos |
And 2 more authors.
Avian Pathology | Year: 2013
A novel avipoxvirus caused diphtheritic lesions in the oesophagus of five and in the bronchioli of four Magellanic penguins (Spheniscus magellanicus) and also cutaneous lesions in eight Magellanic penguins housed in outdoor enclosures in a Rehabilitation Centre at Florianópolis, Santa Catarina State, Brazil. At the same time, another avipoxvirus strain caused cutaneous lesions in three Magellanic penguins at a geographically distinct Rehabilitation Centre localized at Vila Velha, Espírito Santo State, Brazil. Diagnosis was based on clinical signs, histopathology and use of the polymerase chain reaction (PCR). Clinical signs in the penguins included cutaneous papules and nodules around eyelids and beaks, depression and restriction in weight gain. The most common gross lesions were severely congested and haemorrhagic lungs, splenomegaly and cardiomegaly. Histological examination revealed Bollinger inclusion bodies in cutaneous lesions, mild to severe bronchopneumonia, moderate periportal lymphocytic hepatitis, splenic lymphopenia and lymphocytolisis. Other frequent findings included necrotizing splenitis, enteritis, oesophagitis, dermatitis and airsacculitis. Cytoplasmic inclusion bodies were seen within oesophageal epithelial cells in five birds and in epithelial cells of the bronchioli in four penguins. DNA from all samples was amplified from skin tissue by PCR using P4b-targeting primers already described in the literature for avipoxvirus. The sequences showed two different virus strains belonging to the genus Avipoxvirus of the Chordopoxvirinae subfamily, one being divergent from the penguinpox and avipoxviruses already described in Magellanic penguins in Patagonia, but segregating within a clade of canarypox-like viruses implicated in diphtheritic and respiratory disease. © 2013 © 2013 Houghton Trust Ltd.
Navarrete D.,University of Exeter |
Sitch S.,University of Exeter |
Aragao L.E.O.C.,National Institute for Space Research |
Global Change Biology | Year: 2016
Strategies to mitigate climate change by reducing deforestation and forest degradation (e.g. REDD+) require country- or region-specific information on temporal changes in forest carbon (C) pools to develop accurate emission factors. The soil C pool is one of the most important C reservoirs, but is rarely included in national forest reference emission levels due to a lack of data. Here, we present the soil organic C (SOC) dynamics along 20 years of forest-to-pasture conversion in two subregions with different management practices during pasture establishment in the Colombian Amazon: high-grazing intensity (HG) and low-grazing intensity (LG) subregions. We determined the pattern of SOC change resulting from the conversion from forest (C3 plants) to pasture (C4 plants) by analysing total SOC stocks and the natural abundance of the stable isotopes 13C along two 20-year chronosequences identified in each subregion. We also analysed soil N stocks and the natural abundance of 15N during pasture establishment. In general, total SOC stocks at 30 cm depth in the forest were similar for both subregions, with an average of 47.1 ± 1.8 Mg C ha-1 in HG and 48.7 ± 3.1 Mg C ha-1 in LG. However, 20 years after forest-to-pasture conversion SOC in HG decreased by 20%, whereas in LG SOC increased by 41%. This net SOC decrease in HG was due to a larger reduction in C3-derived input and to a comparatively smaller increase in C4-derived C input. In LG both C3- and C4-derived C input increased along the chronosequence. N stocks were generally similar in both subregions and soil N stock changes during pasture establishment were correlated with SOC changes. These results emphasize the importance of management practices involving low-grazing intensity in cattle activities to preserve SOC stocks and to reduce C emissions after land-cover change from forest to pasture in the Colombian Amazon. © 2016 John Wiley & Sons Ltd.
Danilewicz D.,State University of Rio Grande do Sul |
Zerbini A.N.,Instituto Aqualie Av Dr Paulo Japiassu Coelho 714 |
Edmundson W.,Av. Silvino Chaves 481 |
Hart I.B.,Laurel Cottage Newton St. Margarets Herefordshire HR2 0QN UK |
Mammal Review | Year: 2016
Historical catch records from whaling activity are crucial for assessments of whale populations. However, several gaps in the exploitation history for many populations from before the twentieth century create limitations that may lead to overestimates of the recovery of these populations. The history of modern whaling along the Brazilian coast is relatively well known. However, several questions relating to the pre-modern period, during and before the nineteenth century, remain unanswered. For example, the level of exploitation of humpback whales Megaptera novaeangliae and southern right whales Eubalaena australis in this period is unknown. Pre-modern whaling in Brazil began in 1602 and lasted until the 1920s. Whales were captured using manual harpoons from either rowing boats or sailing boats, and processed at land stations called 'armações'. A review of the history and oil production of these stations indicates that substantial catches occurred. Pre-modern whaling records also indicate the collapse of the southern right whale population in the western South Atlantic Ocean. Increasingly rare reports of sightings for the nineteenth century and the closing of the last armação in the breeding grounds off southern Brazil indicate that this population collapsed by 1830. Armações operating in north-eastern Brazil remained active through the 1800s, and targeted humpback whales until modern whaling techniques were introduced in the early 1900s. It is estimated that between approximately 11000 and 32000 individuals of this species were captured at these coastal whaling stations from 1830 to 1924. © 2016 The Mammal Society and John Wiley & Sons Ltd.
Hallwass G.,Federal University of Rio Grande do Sul |
Hallwass G.,Fisheries and Food Institute FIFO |
Lopes P.F.M.,Fisheries and Food Institute FIFO |
Lopes P.F.M.,Federal University of Rio Grande do Norte |
And 4 more authors.
Journal of Environmental Management | Year: 2013
Identifying the factors that influence the amount of fish caught, and thus the fishers' income, is important for proposing or improving management plans. Some of these factors influencing fishing rewards may be related to fishers' behavior, which is driven by economic motivations. Therefore, those management rules that have less of an impact on fishers' income could achieve better acceptance and compliance from fishers. We analyzed the relative influence of environmental and socioeconomic factors on fish catches (biomass) in fishing communities of a large tropical river. We then used the results from this analysis to propose alternative management scenarios in which we predicted potential fishers' compliance (high, moderate and low) based on the extent to which management proposals would affect fish catches and fishers' income. We used a General Linear Model (GLM) to analyze the influence of environmental (fishing community, season and habitat) and socioeconomic factors (number of fishers in the crew, time spent fishing, fishing gear used, type of canoe, distance traveled to fishing grounds) on fish catches (dependent variable) in 572 fishing trips by small-scale fishers in the Lower Tocantins River, Brazilian Amazon. According to the GLM, all factors together accounted for 43% of the variation in the biomass of the fish that were caught. The behaviors of fishers' that are linked to fishing effort, such as time spent fishing (42% of the total explained by GLM), distance traveled to the fishing ground (12%) and number of fishers (10%), were all positively related to the biomass of fish caught and could explain most of the variation on it. The environmental factor of the fishing habitat accounted for 10% of the variation in fish caught. These results, when applied to management scenarios, indicated that some combinations of the management measures, such as selected lakes as no-take areas, restrictions on the use of gillnets (especially during the high-water season) and individual quotas larger than fishers' usual catches, would most likely have less impact on fishers' income. The proposed scenarios help to identify feasible management options, which could promote the conservation of fish, potentially achieving higher fishers' compliance. © 2013 Elsevier Ltd.