2,794 research outputs found
Further infrared systems studies for the earth resources program Final report
Design of multispectral scanner for orbital earth resources detectio
Utilization of Skylab (EREP) system for appraising changes in continental migratory bird habitat
There are no author-identified significant results in this report
Utilization of satellite data for inventorying prairie ponds and lakes. LANDSAT-1 data were used to discriminate ponds and lakes for waterfowl management
The author has identified the following significant results. The mapping of open water as an indicator of waterfowl habitat quality was carried out by using two different recognition techniques, a single waveband thresholding approach and a multiple waveband approach termed proportion estimation. The single waveband technique has proven simple to implement. Its computer algorithm was rapid and accurately recognized prairie lakes and large ponds. The resultant products of this processing technique were thematic maps and statistical tabulations describing open surface water conditions. The maps served to portray visually the location and frequency of surface water bodies but usually necessitated additional interpretation
Application of LANDSAT system for improving methodology for inventory and classification of wetlands
The author has identified the following significant results. Processing of LANDSAT MSS data for detection of prairie ponds and lakes was completed. Data coverage included a 36,876 sq km area in southeastern North Dakota during May and July. Cloud coverage limited the May coverage to 87% of the total area. Data analysis was accomplished using three software programs. Wetland identification by MSS sensors were compared to visual counts obtained by observers in low flying aircraft. Pond numbers identified by LANDSAT averaged about 20% of those counted visually. The discrepancy was attributed to the fact that approximately 75% of the ponds in the glaciated prairie region are less than 0.4 ha in size. It is significant, however, that LANDSAT counts accurately reflect trends
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Breast Cancer Risk Factors and Associations with Breast Cancer Tumor Characteristics in High Risk Populations
Background: Estrogen receptor (ER)- and progesterone receptor (PR)-negative (ER-PR-) breast cancer is associated with higher grade and poorer prognosis compared with other breast cancer subtypes. High parity, coupled with lack of breastfeeding, has been associated with an increased risk of ER-PR- cancer. The mechanism of this etiology is unclear, and may be obfuscated by ER and PR correlation with each other as well as other prognostic tumor characteristics.
Methods: Using population-based and clinic-based ascertained cases and controls from the Breast Cancer Family Registry, I examined reproductive risk factors, including parity, breastfeeding, and oral contraceptive (OC) use, in relation to ER and PR status, using polytomous logistic regression (for the population-based data) and the method of generalized estimating equations (GEE) (for the clinic-based data) as well as the pseudo-conditional likelihood approach, which accounts for correlated outcome variables.
Results: High parity (≥ 3 live births) combined with lack of breastfeeding, was positively associated with ER-PR- tumors (odds ratio [OR]=1.57, 95% confidence interval [CI] 1.10-2.24, population-based cases vs. controls) relative to nulliparity. There was no association with ER-PR- tumors and parity in women who breastfed (OR=0.93, 95%CI 0.71-1.22) relative to nulliparous women. Associations with ER-PR- cancer were higher across all races/ethnicities among women who did not breastfeed compared with women who did. Population-based and clinic-based data were generally in agreement (OR=2.07, 95% CI 1.09-3.91, clinic-based cases vs. controls, relative to nulliparity). When adjusted for the correlation of PR-status and grade, to ER-status, the association between high parity +lack of breastfeeding and ER- status, was maintained. OC use before year 1975 was associated with an increased risk of ER-PR- tumors (OR=1.32, 95% CI 1.04-1.67, population-based data, cases vs. controls) relative to never use of OCs. For women who began OC use in 1975 or later there was no increased risk. Analysis of OC use in clinic-based data agreed with the findings of the population-based data.
Conclusions: My findings support that there are modifiable factors for ER-PR- breast cancer, and that breastfeeding in particular may mitigate the increased risk of ER-PR-cancers seen from multiparity. The mechanism of both risk and risk mitigation may operate primarily through the estrogen, rather than progesterone, pathway
Utilization of ERTS-1 for appraising changes in continental migratory bird habitat
The author has identified the following significant results. Information on numbers, distribution, and quality of wetlands in the breeding range of migratory waterfowl is important for the management of this wildlife resource. Using computer processing of data gathered by the ERTS-1 multispectral scanner, techniques for obtaining indices of annual waterfowl recruitment, and habitat quality are examined. As a primary task, thematic maps and statistics relating to open surface water were produced. Discrimination of water was based upon water's low apparent radiance in a single, near-infrared waveband. An advanced technique using multispectral information for discerning open water at a level of detail finer than the virtual resolution of the data was also successfully tested. In another related task, vegetation indicators were used for detecting conditions of latent or occluded water and upland habitat characteristics
Hygienic Analysis of some of the Potable Waters of Brookings
Introduction: While it is universally recognized that there is a difference between good and bad drinking water, few realize how important a part water plays in producing or destroying health. Comparatively recent investigation has shown that water forms the most active agent in the production as well as the promotion and spread of disease. Water containing organic impurities will, when used, because various forms of disease, while if the water of a well which has received the excreta of a patient suffering from some infectious disease, be drunk, the drinker is almost sure to contract the disease. Pure water may be said not to exist, and the term is only a relative one, meaning water which contains so little more than the theoretical “H2O” that it may be considered as pure. Any matter, therefore, which may be discovered in water, outside of the elementary Oxygen and Hydrogen, may be designated as an impurity. The character of the impurities differs necessarily with the source of the water. In water, form mineral springs and deep bored wells the impurities are generally entirely mineral in nature. Such water may be said to be per iodide of mercury just commonly to be formed. The solution is then left for about 20 hours and 160 grammes of caustic potash added, after which it is rendered more sensitive by the addition of more mercuric chloride and diluted up to one liter. (See more in text
Preliminary evaluation of ERTS-1 for determining numbers and distribution of prairie ponds and lakes
ERTS-1 and aircraft multispectral data collected over a North Dakota test site during July 1972, are compared to evaluate the capability of the satellite sensors to detect numbers and distribution of prairie ponds and lakes. Recognition maps using ERTS-1, MSS 7 data are generated using a level slicing technique. Surface water areas larger than two acres are recognized, but ponds in the one-to two-acre range are detected only at random. The proportion estimation technique will improve the accuracy of area determination and small pond detection
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