scholarly journals Interim Report on the Water Resources of Brevard County, Florida, With Special Reference to the Central Area

10.35256/ic11 ◽  
1957 ◽  
Keyword(s):  
Water Resources ◽  
Special Reference ◽  
Central Area ◽  
Interim Report ◽  
Brevard County

Further Observations upon the Oxyntic Cells with Special Reference to Acid Phosphatase

1952 ◽  
Vol s3-93 (23) ◽  
pp. 259-268
Author(s):  
GORDON MENZIES
Keyword(s):  
Acid Phosphatase ◽  
Special Reference ◽  
Single Injection ◽  
Central Area ◽  
Basal Part ◽  
Prolonged Starvation ◽  
Apparent Change ◽  
Multiple Doses ◽  
Hydrolysis Of ◽  
In Cells

1. In continuation of work already reported (Menzies, 1949) further data are presented on the structure and cyto-chemistry of the granules in the oxyntic cells of the rat's stomach. 2. After multiple doses of pilocarpine or histamine, and after feeding, the phospholipine (as shown by acid haematein) is shed from some or all of the granules. The lipine first leaves the granules in cells situated in the basal part of the tubules, and finally those in the neck of the tubules, but a non-lipine lipoid remains in all the granules (as shown by sudan black). 3. The granules enlarge after prolonged starvation as they do after a single injection of pilocarpine; but after extraction of lipoids by hot pyridine and subsequent straining with iron haematoxylin, enlargement (i.e. of the non-lipoid moiety) is shown only after prolonged starvation. 4. A light, uncoloured central area is found in some of the largest granules after feeding and colouring with acid haematein. 5. An acid phosphatase appears in the oxyntic cells whose granules are about to lose their lipine component, and it disappears when they have done so. It is suggested that the acid phosphatase may cause hydrolysis of the phospholipine. 6. Only after prolonged starvation is there any apparent change in granule numbers, when they are decreased.

Optimization of an Integrated Water Resources Model in tropical regions

2020 ◽  
Author(s):  
Leonardo David Donado ◽  
María Cristina Arenas-Bautista
Keyword(s):  
Water Quality ◽  
Water Resources ◽  
Optimization Model ◽  
Water Demand ◽  
Water Quality Management ◽  
Central Area ◽  
Population Increase ◽  
Tropical Region ◽  
Planning Period ◽  
Tropical Regions

<p>Water resources management must be in all cases, effective, efficient and sustainable, especially when considering the effects of climate change and variability effects. The challenge tackled in this research was to build a hydro-economic optimization model, which can be used as a decision-making tool for water assignment between several users in a tropical region. The model has been developed by integrating hydrological aspects (surface water and groundwater) in an economical optimization framework for water allocation and water quality management.</p><p>We study a basin of 17 000 km2 located in the Colombian Middle Magdalena Valley (MMV), a central area with important economic activities, as oil and gas exploration and production (O&G), agriculture and livestock.</p><p>A regional optimization model that integrates multiple water supplies and demands were designed.  The main purpose of the model is to maximize the value of water consumption. Consequently, the hydro-economic model was solved through a lineal optimization process, that links all available water resources and all water demands under the limitations of: (i) demand rising, (ii) water quality variance and (ii) offer decrease.</p><p>The system considers the monthly water demand from each user and a penalty for no satisfy it. For hydro-economic analysis, the model contemplates four main study scenarios: (i) current mean condition (ESC1), (ii) at thirty years (ESC2), (iii) at fifty years (ESC3) and, (iv) at hundred years (ESC4). These scenarios show fluctuation in water demand, and water supply based on the population increase. The results show significant differences between the user's allocation regimes. This has been identified between domestic and agricultural sectors, but not between commercial activities. According to the later, it is important to include variable rates for each sector according to its productivity, in the general analysis.</p><p>The defined objective function maximizes the profit in the MMV basin during a planning period of a year.  It is important to highlight that the whole system was optimized under an equitable distribution in allocation and costs, and thus, the resulting profits would improve results to satisfy all economic sectors.</p>

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