Kenya consumes 4-7 thousand tons of charcoal per day. Much of Kenya’s charcoal comes from shrubland or savannah. After harvest, this land may be allowed to regenerate, but increasingly charcoal is used as a means to clear land for crop cultivation. This is particularly true in Narok District, one of Kenya’s main charcoal production areas and an increasingly important grain production zone. Land management specifically for charcoal is extremely rare. Charcoal production and use is associated with high greenhouse gas emissions relative to other common energy options. However, there have been few attempts to analyze the land-use change implications associated with different charcoal production systems, This paper uses computer modeling parameterized with empirical data to analyze the carbon dynamics of current charcoal production practices, including changes in stocks of soil and biomass carbon resulting from land cover change linked to charcoal production. On a life cycle basis, the common practice of charcoal production followed by grain cultivation leads to a loss of 40 tC per ha (2.7 tC per ton of charcoal produced). Charcoal production by coppice management of native vegetation releases 3-9 tC per ha over 50 years of management (0.08-0.3 tC per ton of charcoal produced). Charcoal production using a fast growing exotic species (eucalyptus grandis) managed on a 10-year coppice managed cycle results in a net sink of 150 tC per ha (0.5-0.8 tC sequestered per ton of charcoal produced). These results are compared to life cycle emissions from other common household fuels and policy implications are discussed.

The rise of Internet-scale geo-replicated services has led to upheaval in the design of modern data management systems. Given the availability, latency, and throughput penalties associated with classic mechanisms such as serializable transactions, a broad class of systems (e.g., "NoSQL") has sought weaker alternatives that reduce the use of expensive coordination during system operation, often at the cost of application integrity. When can we safely forego the cost of this expensive coordination, and when must we pay the price?

In this thesis, we investigate the potential for coordination avoidance---the use of as little coordination as possible while ensuring application integrity---in several modern data-intensive domains. We demonstrate how to leverage the semantic requirements of applications in data serving, transaction processing, and web services to enable more efficient distributed algorithms and system designs. The resulting prototype systems demonstrate regular order-of-magnitude speedups compared to their traditional, coordinated counterparts on a variety of tasks, including referential integrity and index maintenance, transaction execution under common isolation models, and database constraint enforcement. A range of open source applications and systems exhibit similar results.

It is well-documented that energy and energy systems have a central role in social and economic development and human welfare at all scales, from household and community to regional and national (41). Among its various welfare effects, energy is closely linked with people s health. Some of the effects of energy on health and welfare are direct. With abundant energy, more food or more frequent meals can be prepared; food can be refrigerated, increasing the types of food items that are consumed and reducing food contamination; water pumps can provide more water and eliminate the need for water storage leading to contamination or increased exposure to disease vectors such as mosquitoes or snails; water can be disinfected by boiling or using other technologies such as radiation. Other effects of energy on public health are mediated through more proximal determinants of health and disease. Abundant energy can lead to increased irrigation, agricultural productivity, and access to food and nutrition; access to energy can also increase small-scale income generation such as processing of agricultural commodities (e.g., producing refined oil from oil seeds, roasting coffee, drying and preserving fruits and meats) and production of crafts; ability to control lighting and heating allows education or economic activities to be shielded from daily or seasonal environmental constraints such as light, temperature, rainfall, or wind; time and other economic resources spent on collecting and/or transporting fuels can be used for other household needs if access to energy is facilitated; energy availability for transportation increases access to health and education facilities and allow increased economic activity by facilitating the transportation of goods and services to and from markets; energy for telecommunication technology (radio, television, telephone, or internet) provides increased access to information useful for health, education, or economic purposes; provision of energy to rural and urban health facilities allows increased delivery and coverage of 3 various health services and interventions such as tests and treatments, better storage of medicine and vaccines, disinfection of medical equipment by boiling or radiation, and more frequent and efficient health system encounters through mobile clinics or longer working hours; and so on. In fact, while the dominant view of development-energy-health linkages has been that improvements in energy and health are outcomes of the socioeconomic development process (e.g., the "energy ladder" framework discussed below), it has even been argued that access to higher quality energy sources and technologies can initiate a chain of demographic, health, and development outcomes by changing the household structure and socioeconomic relationships. For example, in addition to increased opportunities for food and income production, reduced infant mortality as a result of transition to cleaner fuels or increased coverage of vaccination with availability of refrigerators in rural clinics may initiate a process of "demographic transition" to low-mortality and low-fertility populations (14). Such a transition has historically been followed with further improvements in maternal and child health and increased female participation in the labor markets and other economic activities.