SMALL FARM POLICY: WHAT ROLE FOR THE GOVERNMENT?

Agricultural and Food Policy,

TOWARD A MORE COMPLETE COMPARISON OF FARM AND NONFARM PROPRIETORSHIP INCOME

Farm Management,

Thermo-chemical conversion of dairy waste based biomass through direct firing

Growing rates of manure produced from large dairies have increased concern for the environmental quality of nearby streams and watersheds. Typically the manure from the freestalls on these dairies is flushed with water to a mechanical separator. Here, flushed dairy biomass (DB) is parted into separated solids and separated liquid. The separated liquid is discharged into lagoons for treatment and eventual land application. This thesis proposes thermodynamic models for firing DB in small scale boiler systems that would eliminate land application and lagoons, which are being claimed to be the source of nutrient leaching and overloading. Fuel analysis of flushed DB from a dairy in central Texas show that it contains 93%moisture (%M), 3%ash (%A), and 4%combustibles (%Cb), while separated DB solids contain 81%M, 2%A, and 17%Cb. The dry, ash-free higher heating value of DB is approximately 20,000 kJ/kg. Using dry, ash-free results, computations can be made over ranges of %M and %A. For example, DB containing 70%M requires 9.74%Cb to vaporize all moisture and produce gaseous products of combustion at 373 K, but requires 17.82%Cb to burn in a regenerative combustor with a flame temperature of 1200 K. Separated solids that are pressed in an auger to 70%M (3%A and 27%Cb) can burn at 1200 K with exhaust temperatures of up to 1130 K and a minimum required heat exchanger effectiveness of 15%. Pressed solids can thus be fired in a boiler, where the remaining separated liquid can be used as feed water. The pressed solids only can release about 30% of the heat required to vaporize the remaining unclean feed water. However, pressed DB solids can be blended with drier fuels to vaporize almost all the unclean water. The low quality steam produced from the unclean water can be used in thermal processes on the farm. A similar system can be developed for vacuumed DB without the need to vaporize unclean feed water. As for large dairies with anaerobic digester systems already installed, directly firing the produced biogas in a small scale boiler system may be another way to similarly vaporize the remaining effluent

More air force per dollar as applied to facilities contracts.

Thesis (M.B.A.)--Boston Universit

Objective Measurement of Walking Activity Using Wearable Technologies in People with Parkinson Disease: A Systematic Review Protocol

Introduction Parkinson's disease (PD) is a complex neurodegenerative disease with motor and nonmotor symptoms with a multitude of disease variations and severity. Physical activity can improve the management of disease symptoms and increase patients' quality of life. Technological development of small wearable devices allows objective activity measurement such as daily step count. Objective To synthesize ongoing and past research on objective walking activity measurements using wearable devices in patients with PD. Methods PubMed, Cochrane, Web of Science, and PEDro database are systematically searched with no limitation on publication date. Keywords are relative to (1) the population, (2) the measurement tool, and (3) the measured outcomes. Only full-text English articles published in a peer-reviewed journal will be included. Participants do not have to undergo any type of intervention. Included studies must report an objective measurement of walking activity using wearable devices in PD patients. After an independent screening process done by 2 reviewers, data will be extracted from the articles according to the following 5 set of data: (1) the study metrics, (2) the population characteristics, (3) the measurement tools, (4) the experimental procedure, and (5) the reported outcomes. Results The results will contain inter alia summaries of the wearables' specifications, wearing location, and recommendations for feasible methodologies to capture daily walking activity. Discussion This review aims to synthesize the evidence of objective walking activity assessment with wearable devices in patients with PD. It will also provide recommendations with regard to device selection and suggest key points when monitoring walking activity in this specific population

Assessing range limits and niche shifts in invasive weeds : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University

Invasive species pose global threats to the environment, human health, and endemic species. Being able to predict which species will become invasive, and which countries are vulnerable, helps prevent species invasions before they occur. Current methods consider which environments a species occupies in the native range and extrapolates this onto new regions. However, when species undergo niche shifts they occupy different environments in the introduced range than those they occupied in the native range. In this thesis I will combine statistical and empirical approaches to uncover what processes lead to niche shifts, and provide a better understanding of how to predict species’ distributions in the presence of niche shifts. To accomplish this I consider three globally invasive ruderal weed species: Rumex obtusifolius Linnaeus, R. crispus L., and R. conglomeratus Murray. I begin by assessing where Rumex species undergo niche shifts globally. I found that Rumex species undergo different niche dynamics in each of the three non-native regions considered. In New Zealand, the climatic niche expanded towards warmer, wetter climates; in Australia, the niche was largely conserved; and in North America the niche predominantly expanded into drier, less stable climates. From here, I wanted to understand which variables were best at predicting species’ distributions both in the native and introduced range where the species were shown to have undergone a niche shift. Here I considered land use, human-related, and hydrological non-climatic variables. Whilst climatic variables are the most commonly used variables in predicting species’ distributions, I found that climate models often underperformed when compared to non-climatic models. In particular, when projecting models from the native range onto the introduced ranges the inclusion of climatic variables was detrimental to model performance. Utilising non-climatic variables, such as human impact, resulted in more accurate model projections. Finally, I conducted a large-scale common garden experiment in the introduced range to ascertain whether individuals from the introduced range had evolved to occupy new niche space beyond what individuals from the native range tolerate. Contrary to my expectations, I found that climatic niche shifts in Rumex species are the result of preadaptation rather than rapid evolution. This study is the first of its kind to consider niche shifts across multiple introduced regions and provide experimental evidence of how species are capable of shifting their niches into non-analogue climates. In this thesis I will provide new insights into how we assess niche shifts, and open new avenues for future research. I suggest that we should first focus on better understanding the species’ fundamental niche, before assessing whether species have undergone rapid adaptation in new regions

Thermo-chemical conversion of dairy waste based biomass through direct firing

Growing rates of manure produced from large dairies have increased concern for the environmental quality of nearby streams and watersheds. Typically the manure from the freestalls on these dairies is flushed with water to a mechanical separator. Here, flushed dairy biomass (DB) is parted into separated solids and separated liquid. The separated liquid is discharged into lagoons for treatment and eventual land application. This thesis proposes thermodynamic models for firing DB in small scale boiler systems that would eliminate land application and lagoons, which are being claimed to be the source of nutrient leaching and overloading. Fuel analysis of flushed DB from a dairy in central Texas show that it contains 93%moisture (%M), 3%ash (%A), and 4%combustibles (%Cb), while separated DB solids contain 81%M, 2%A, and 17%Cb. The dry, ash-free higher heating value of DB is approximately 20,000 kJ/kg. Using dry, ash-free results, computations can be made over ranges of %M and %A. For example, DB containing 70%M requires 9.74%Cb to vaporize all moisture and produce gaseous products of combustion at 373 K, but requires 17.82%Cb to burn in a regenerative combustor with a flame temperature of 1200 K. Separated solids that are pressed in an auger to 70%M (3%A and 27%Cb) can burn at 1200 K with exhaust temperatures of up to 1130 K and a minimum required heat exchanger effectiveness of 15%. Pressed solids can thus be fired in a boiler, where the remaining separated liquid can be used as feed water. The pressed solids only can release about 30% of the heat required to vaporize the remaining unclean feed water. However, pressed DB solids can be blended with drier fuels to vaporize almost all the unclean water. The low quality steam produced from the unclean water can be used in thermal processes on the farm. A similar system can be developed for vacuumed DB without the need to vaporize unclean feed water. As for large dairies with anaerobic digester systems already installed, directly firing the produced biogas in a small scale boiler system may be another way to similarly vaporize the remaining effluent