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Ramirez Solar House : A Case Study Of Early Solar Design, Joanna Kendig

Theses

The Ramirez Solar House in the Delaware Water Gap National Recreation Area is an early historic example of passive solar design. The house was designed by Henry N. Wright, a significant contributor in solar research. Wright's 1944 design with a large window wall and generous overhangs represents a significant step in solar design development. The house, now under the stewardship of National Park Service, has been nominated for the National Register of Historic Places.

The Ramirez House's solar performance was a subject of this study. Instrumentation was set up to record temperatures, humidity and illumination in the unoccupied and un-heated …

Changes In The Distribution Of Lepidopteran Maize Stemborers In Kenya From The 1950s To 1990s, Zhou Guofa, William A. Overholt, Moses B. Mochiah

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Three hundred and ninety-two maize fields in the southern arable zone of Kenya were sampled for lepidopteran cereal stemborers from 1996-2000. Chilo partelhis (Swinhoe) was the most abundant stemborer, and was found at all locations with elevations below 1500 m, and at some locations between 1500 and 2300 m. The highest density of C. partelhis was in the semi-arid ecological zone of eastern Kenya. Chilo orichalcociliellus (Strand) was found in the lowland southern coastal area, and a few inland sites on the border of Tanzania in southeastern Kenya. Busseola fusca Fuller was dominant in highland areas. In the Lake Victoria …

Relationships Of Stemborer Damage And Plant Physical Conditions To Maize Yield In A Semi-Arid Zone Of Eastern Kenya, Josephine Moraa Songa, Zhou Guofa, William Allan Overholt

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A field survey on maize stemborers, stemborer damage, maize plant physical conditions, and maize yield was conducted in eastern Kenya under natural conditions. Chilo partellus was the dominant stemborer accounting for 89.5 % of all borers. Stemborer damage greatly reduced maize yield, with tunnel lengths greater than 20 cm causing a 40 % reduction of potential yield. A 33 % yield loss was found in plants with more than one stemborer exit hole. Each stemborer (at harvest time) was correlated with a 8-10 % yield loss. Good plant physical characteristics significantly increased grain yield. Principle component analysis showed that stemborer …

Impact Of Solar Radiation Rainfall And Cannibalism On Disappearance Of Maize Stemborers In Kenya, M. J. Bonhof, W. A. Overholt

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The effect of solar radiation, rainfall and cannibalism on the disappearance of eggs and larvae of the cereal stemborer Chilo partellus (Swinhoe) were studied. Disappearance and nonviability of egg batches was higher on plants exposed to solar radiation than on shaded plants. Significantly fewer small larvae were recovered from plants exposed to rainfall than from shielded plants. Cannibalism among larvae of the same size was not common except at high larval densities. Contrary to the common belief that disappearance is the result of prédation, these studies show that solar radiation and rainfall might also play an important role in the …

Properties Of A Factor In Eland Plasma That Inhibits Transformation Of Bloodstream-Form Trypanosoma Brucei Brucei, E. K. Nguu, E. O. Osir

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Fresh plasma from the African eland, Taiirotragus oryx, contains a factor that inhibits the transformation of bloodstream-form Trypanosma bnicei bntcei into procyclic (midgut) forms. Heating of the plasma at 42, 50 and 60 °C for 30 min resulted in a 20, 38 and 40% loss of inhibitor activity respectively, whereas only negligible loss occurred below 42 C. Similarly, one and four freeze-thawing cycles resulted in 32 and 60% loss of activity respectively. Inactivation of the inhibitor activity, which occurred rapidly during storage (for example, 80% loss after 7 days at -20 °C) could not be stopped by the addition of …

Habitat Management Strategies For The Control Of Cereal Stemborers And Striga In Maize In Kenya, Z. R. Khan, J. A. Pickett, L. Wadhams, F. Muyekho

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Maize is the principal food and cash crop for millions of people in the predominantly mixed crop-livestock farming systems in Kenya. Stemborers and striga (Striga hermonthica) are major constraints to increased maize production in eastern Africa. An intercropping and trap crop system has been developed, using a ‘push-pull’ strategy, for the control of stemborers in small scale maize farming systems. The ‘push-pull’ strategy involves trapping stemborers on highly susceptible trap plants (pull) and driving them away from the crop using repellent intercrops (push). Napier grass (Pennisetum piirpiirenm Schumach) and Sudan grass (Sorghum vulgare sudanense Stapf J are used as trap …

Stemborer Research In Zimbabwe: Prospects For The Establishment Of Cotesia Flavipes Cameron, P. Clhnwada, C. O. Omvvega, W. A. Overholt

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The stemborers Busseola fnsca (Fuller) and Chilo partellus (Svvinhoe) cause the highest economic damage to maize and sorghum in Zimbabwe. A number of studies on stemborer bioecology and management in Zimbabwe have been conducted, but most are still incomplete. The more important of these are studies on life history, incidence and distribution patterns, host plants, yield losses, chemical control, cultural control, host plant resistance, the use of sex pheromones, and biological control. These are discussed here in detail, and areas where further research is needed are pointed out. As part of an integrated strategy for managing stemborers in Zimbabwe, an …

Human Health Improvement In Sub-Saharan Africa Through Integrated Management Of Arthropod Transmitted Diseases And Natural Resources., J. Baumgärtner, M. Bieri, G. Buffoni, G. Gilioli, H. Gopalan, J. Greiling, G. Tikubet, I. Van Schayk

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A concept of an ecosystem approach to human health improvement in Sub-Saharan Africa is presented here. Three factors mainly affect the physical condition of the human body: the abiotic environment, vector-transmitted diseases, and natural resources. Our concept relies on ecological principles embedded in a social context and identifies three sets of subsystems for study and management: human disease subsystems, natural resource subsystems, and decision-support subsystems. To control human diseases and to secure food from resource subsystems including livestock or crops, integrated preventive approaches are preferred over exclusively curative and sectorial approaches. Environmental sustainability - the basis for managing matter and …

Spatial And Temporal Distribution Of Tsetse Fly Trap Catches At Nguruman, Southwest Kenya, A. Odulaja, J. Baumgärtner, S. Mihok, I. M. Abu-Zinid

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Spatial and temporal dynamics of rapidly growing populations of tsetse flies at Nguruman, southwest Kenya during 1993-1995, were investigated, following six years of intensive population suppression with traps over a c. 100 km2 area. The two tsetse species present were randomly distributed in the short rainy season, but were aggregated in the dry and long rainy seasons. Maximum temperature was the dominant weather factor associated with the degree of aggregation. Trends in catches at 20 fixed sites along an 18 km north-south axis were weakly correlated between locations, possibly representing population sub-structuring. In particular, trends in population change were poorly …