Sökning: "Centralamerika"

Hittade 4 avhandlingar innehållade ordet Centralamerika.

  1. 1. Observational Uncertainties in Water-Resources Modelling in Central America : Methods for Uncertainty Estimation and Model Evaluation

    Författare :Ida Westerberg; Sven Halldin; Jan Seibert; Lars-Christer Lundin; Chong-Yu Xu; Deliang Chen; Alberto Montanari; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Central America; Discharge; Flow-duration curve; Fuzzy regression; GLUE; Model evaluation; Non-stationarity; Observational uncertainty; Precipitation; Quality control; Rating curve; Regionalisation; Uncertainty estimation; Ungauged basins; Water resources; Avbördningskurva; Centralamerika; GLUE; icke-stationaritet; kvalitetskontroll; modellutvärdering; nederbörd; observationsosäkerheter; avrinningsområden utan vattenfö-ringsdata; oskarp regression; osäkerhetsuppskattning; regionalisering; varaktighetskurva; vattenföring; vattenresurser; Hydrology; Hydrologi; Hydrology; Hydrologi;

    Sammanfattning : Knowledge about spatial and temporal variability of hydrological processes is central for sustainable water-resources management, and such knowledge is created from observational data. Hydrologic models are necessary for prediction for time periods and areas lacking data, but are affected by observational uncertainties. LÄS MER

  3. 2. Purification, Stereoisomeric Analysis and Quantification of Biologically Active Compounds in Extracts from Pine Sawflies, African Butterflies and Orchid Bees

    Författare :Joakim Bång; Erik Hedenström; Kristina Sjödin; Hans-Erik Högberg; Anna-Karin Borg-Karlsson; Mittuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Semiochemicals; sex pheromone; pine sawflies; Bicyclus; Euglossa; chiral separation; derivatisation; GC-­MS; Organic chemistry; Organisk kemi;

    Sammanfattning : Stereochemistry plays an important role in nature because biologically important molecules such as amino acids, nucleotides and sugars, only exist in enantiomerically pure forms. Semiochemicals carry messages, between the same species (pheromones) and between different species (allelochemicals). LÄS MER

  4. 3. The Cyanophyte Arthrospira Fusiformis in African Waters - Eco-Physiology and Potential Use in Tropical Aquaculture

    Författare :Aidate Mussagy; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; limnology; Marinbiologi; marine biology; aquatic ecology; lipopolysaccharide endotoxins LPS ; salinity; osmoregulation; proline; aquaculture feeds; Artemia.; Hydrobiology; anatoxin; microcystin; ITS sequences; phenotype analysis; taxonomy; Cyanophyceae; Arthrospira fusiformis; limnologi; akvatisk ekologi;

    Sammanfattning : The cyanoprokaryote (blue-green algae) genus Arthrospira occurs in saline, alkaline tropical waters of Africa, Asia, and Central America. Traditionally Arthrospira has been used as a food supplement by the Kanembu tribe of Lake Chad and Aztecs living in the valley of Mexico City. LÄS MER

  5. 4. Child labour and health hazards: chemical exposure and occupational injuries in Nicaraguan children working in a waste disposal site

    Författare :Steven Cuadra; Avdelningen för arbets- och miljömedicin; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; child labor; waste disposal sites; health hazards; heavy metals; persistent organochlorine pollutants; brominated flame retardants; occupational injuries; Nicaragua; barnarbete; avfallshanteringsplatser; hälsorisker; tungmetaller; beständiga klororganiska föroreningar; bromerade flamskyddsmedel; yrkesskador; Nicaragua;

    Sammanfattning : About 600 children and teenagers work at Managua's landfill, the largest in Nicaragua. They collect and sort waste at the open dump, which covers an area of 7 km2 on the outskirts of the city on the shores of Lake Managua. LÄS MER