Environmental Potentials
Mostrando 25-36 de 50 artigos, teses e dissertações.
-
25. "Modelagem espacial para atividades de visitação pública em áreas naturais". / GIS environmental modelling for recreational activities in protected areas
Recreational activities in wildland areas are being considered a way to achieve development and protect the environment. However, without a planning program that considers the factors related to their sustainability, they can cause serious ecological, economic and social impacts. In Brazil, in spite of the recent concerns about recreational problems, there i
Publicado em: 2003
-
26. Desenvolvimento sustentavel : uma analise do alcool como alternativa energetica
World energetic matrix based on combustible fossils, more importantly oil has shown signs of unsustainability. The reasons for this are related to both production structure, which needs to be diversified as to incorporate new sources of energy, and also to the actual pattern of consumption. There is plenty of evidence to suggest that humankind evolution will
Publicado em: 1999
-
27. Planejamento e projeto de sistemas sustentaveis para produção de alimentos pela abordagem do ecodesenvolvimento : bases metodologicas e estudo de caso
A methodology is proposed for conception, planning and project of agro-industrial systems, in order to design them as "sustainable" taking into account their economic efficiency, relationship with ecosystem and quality of life offered to population involved in production and consumption. The methodology developed has the support of several theoretical concep
Publicado em: 1999
-
28. A redução de Cr (VI) sobre carbono vitreo reticulado : ensaios preliminares de sua remoção eletrolitica
Chromium, despite presenting a high toxic potential, is widely used in several industrial activities, especially in the finishing of metal ware. The concern for environmental issues has led to development of alternative methods for the treatment of the residues, since conventional treatments produce toxic sludge. The study of the reduction of Cr(VI) is aimed
Publicado em: 1997
-
29. Effect of Salinity upon Cell Membrane Potential in the Marine Halophyte, Salicornia bigelovii Torr
The electrophysiology of root cells of the marine halophyte, Salicornia bigelovii Torr., has been investigated. Cellular concentrations of K+, Cl−, and Na+ and resulting cell membrane potentials were determined as functions of time and exposure to dilutions of artificial seawater. Treatment of these data by the Nernst criterion suggests that Cl− is activ
-
30. Microbial populations and hydrocarbon biodegradation potentials in fertilized shoreline sediments affected by the T/V Exxon Valdez oil spill.
The effort of clean up the T/V Exxon Valdez oil spill in Prince William Sound, Alaska, included the use of fertilizers to accelerate natural microbial degradation of stranded oil. A program to monitor various environmental parameters associated with this technique took place during the summer of 1990. Microbiological assays for numbers of heterotrophic and o
-
31. Nitrate Reductase Activity in Maize (Zea mays L.) Leaves: II. Regulation by Nitrate Flux at Low Leaf Water Potential 1
Experiments were conducted to determine whether the nitrate flux to the leaves or the nitrate content of the leaves regulated the nitrate reductase activity (NRA) in leaves of intact maize (Zea mays L.) seedlings having low water potentials (ψw) when other environmental and endogenous factors were constant. In seedlings that were desiccated slowly, the nitr
-
32. Response of Tomato Plants to Stressful Temperatures 1: INCREASE IN ABSCISIC ACID CONCENTRATIONS
To investigate the abscisic acid (ABA) production of tomato (Mill.) plants in response to diurnal stressful temperatures, five-week old seedlings were exposed to day/night temperatures of 10/5, 15/10, 25/15, 35/25, or 45/35 C. The daylength was 16 hours with a light intensity of approximately 400 microeinsteins per meter per second. Plant tops were sampled a
-
33. Genetic Diversity and Spoilage Potentials among Pseudomonas spp. Isolated from Fluid Milk Products and Dairy Processing Plants
Degradation of milk components through various enzymatic activities associated with the contamination of dairy products by Pseudomonas spp. can reduce the shelf life of processed milk. Reliable methods for differentiating among Pseudomonas spp. strains are necessary to identify and eliminate specific sources of bacterial contamination from dairy processing s
American Society for Microbiology.
-
34. Water Relations of Cotton Plants under Nitrogen Deficiency: II. Environmental Interactions on Stomata
Nitrogen deficiency in cotton plants (Gossypium hirsutum L.) considerably increased the sensitivity of stomata to water stress. At air temperatures of 27, 35, and ≥40 C, threshold potentials for complete stomatal closure were −10, −15, and −26 bars in N-deficient plants and −20, −20, and −30 bars in high-N plants, respectively. This three-way i
-
35. Intracellular potassium as a possible inducer of amino acid transport across hamster jejunal enterocytes.
Brush border membrane potentials (Vm), intracellular K+ activity (aiK) and alanine uptake were measured in different parts of villi in mid-jejunal tissue taken from hamsters fed different amounts of food at high and low environmental temperatures. Basal villus enterocytes (Y cells) were found to have lower values for Vm and aiK than upper villus enterocytes
-
36. Leaf Water Stress in Engelmann Spruce: Influence of the Root and Shoot Environments 1
The response of xylem pressure potential of Engelmann spruce (Picea engelmannii Engelm.) to environmental factors was studied in the natural subalpine environment. Data were analyzed in the context of a leaf water potential model based upon the van den Honert model for water transport through the soil-plant-atmosphere continuum. At soil temperatures of 10 to