Open windrow composting of polymers: An investigation into the rate of degradation of polyethylene

The compostability of degradable polymers under open windrow composting conditions is explored within this paper. Areas for consideration were the use of, and impacts of, degradable polyethylene (PE) sacks on the composting process and the quality of the finished compost product. These factors were investigated through polymer weight loss over the composting process, the amount of polymer residue and chemical contaminants in the finished compost product, the windrow temperature profiles and a bioassay to establish plant growth and germination levels using the final compost product. This trial also included a comparative study of the weight loss under composting conditions of two different types of ‘degradable’ polymer sacks currently on the European market: PE and a starch based product. Statistical analysis of the windrow temperature profiles has led to the development of a model, which can help to predict the expected trends in the temperature profiles of open compost windrows where the organic waste is kerbside collected using a degradable PE sack

A Simulated Annealing Algorithm for the Optimization of Multistage Depressed Collector Efficiency

The microwave traveling wave tube amplifier (TWTA) is widely used as a high-power transmitting source for space and airborne communications. One critical factor in designing a TWTA is the overall efficiency. However, overall efficiency is highly dependent upon collector efficiency; so collector design is critical to the performance of a TWTA. Therefore, NASA Glenn Research Center has developed an optimization algorithm based on Simulated Annealing to quickly design highly efficient multi-stage depressed collectors (MDC)

Should Abortion Laws Be Liberalized Or Repealed?

During the past few years one of the most complex moral legal problems of our history has surfaced. It is the question of whether the abortion laws currently on the state law books should be liberalized or even removed entirely. The question has been argued and discussed in probably every legislature in the land. Special public hearings on the subject have heard emotional witnesses either deploring the thought of innocent human life being taken or extolling the benefits of a liberalized law that would allow only wanted children to be born. In Montana's own emotional public hearing on House Bill 554 a packed room heard shocking stories of fetuses being aborted alive, of women dying as the result of illegal abortions and of the threat of a Nazi mentality developing in this country Although the intentions of both opponents and proponents were sincere, it is my feeling that public hearings such as the one held on HB 554 do as much to obscure the issues as they do to enlighten. Opponents and proponents come well armed with sensational reports they have picked up to buttress their arguments, the testimony becomes emotional and one-sided, the audience becomes caught up in the emotion and polarizes behind one of the sides. The end result is highly irrational. People leave thinking that they have been enlightened and that they know their own position, when actually all that has happened is that they have accepted a one-dimensional answer to a many-dimensional question. The realization that the abortion question has many dimensions all of which demand painful moral considerations is the first step in a meaningful analysis. As Daniel Callahan says, "Abortion is at once a moral, medical, legal, sociological, philosophical, demographical, and psychological problem, not readily amenable to one-dimensional thinking."1 In view of this fact, this paper will try to deal with the many dimensions of the abortion question. It will focus primarily on what the law has said about abortion. To limit the consideration solely to the legal side would, however, be meaningless. Attention must also be given to why people are demanding the right to abortion, what are the arguments for and against, and what does medical science have to offer on this difficult question. These are the basic dimensions that will be treated with the purpose always being to determine if abortion laws should be removed or liberalized

Off-Site Mitigation and the EIS Threshold: NEPA\u27s Faulty Framework

Only a comprehensive EIS will ensure that agencies adopt the safest and most effective off-site mitigation measures. The CEQ regulations support this view and discourage FONSIs justified by off-site mitigation except in limited circumstances. To encourage full disclosure and public participation in the NEPA process the CEQ, in Forty Questions, mandates the preparation of an EIS whenever an action may have significant impacts on the environment regardless of mitigation unless such measures are imposed by law or included in the original proposal. Hopefully, the CEQ regulations will be amended so that the courts can regard this proposal as binding on the agencies. The present NEPA procedural framework allows and even encourages both agencies and courts to engage in cursory and inadequate review of off-site mitigation. A legal distinction between on-site and offsite mitigation must be acknowledged in order to improve the decisionmaking process. While it is undeniable that mitigation should remain an agency option to be utilized to avoid preparing a FONSI, the circumstances under which this can be done need to be clearly outlined. Only then will judicial review of these proposals assure that NEPA\u27s substantive mandate is satisfied

Using Value-Focused Thinking to Evaluate the Practicality of Porous Pavement Parking Areas on Air Force Installations

Natural runoff processes have been altered by urban development; impervious surfaces (rooftops, highways, parking areas) and their associated storm water systems channel runoff from a vast area into one concentrated outflow. This storm water runoff can cause erosion, flooding, landslides, and significant damage to aquatic ecosystems. Runoff from highways and parking areas has also been known to contain high levels of suspended solids, heavy metals and hydrocarbons. Porous pavements allow infiltration of water through typically impervious surfaces, reducing storm water volumes and acting as a pollutant filtration system. Since there is currently no methodology for Air Force decision-makers to compare conventional and porous pavements, a model was created using Value-Focused Thinking (VFT) to evaluate different paving options. Four porous paving alternatives were compared against two conventional paving alternatives at three separate geographic locations. These alternatives were scored using a total of 12 evaluation measures that were identified as important to the pavement selection process. Structural turf was found to be the best option for northern tier locations, while conventional asphalt was the best choice for central and southern areas. VFT was also shown to be an effective methodology for comparing conventional and porous paving alternatives, objectively weighing economic costs against environmental considerations

Five Cilia in the Anterior Chamber

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Evaluating Ecohydrological Separation with Geochemical Tracers, Δ2H and Δ18O, from Northern California in an Irrigated and Semi-arid Setting

The two water worlds hypothesis challenges the widely accepted ecohydrology tenet that plant roots access a single, homogeneous reservoir of soil water (McDonnell, 2014). This project aspired to advance the understanding of the two water worlds, or ecohydrological separation (ES) of soil water reservoirs, applied to an irrigated agricultural setting. This study also aimed to correlate plant root morphology with plant water uptake. Using geochemical tracers, δ2H and δ18O, isotopic analysis of soil and plant tissue was used to evaluate irrigated plant water acquisition. Field work was conducted on two irrigated farms, Full Belly Farm and Riverdog Farm, in the Capay Valley of northern California, where the Mediterranean climate best exhibits ES. The fact that northern California is both an agricultural hub and drought-prone region makes this location a particularly interesting area to conduct precision agriculture research. Overall, results for the original objectives of this project were inconclusive due to a lack of method development. Taking on a new direction, the redirected focus of this project aimed to use soil water isotopes to determine the pre-evaporative isotopic composition of soil water. The intersection between the local meteoric water line (LMWL) and linear regression through soil water isotopes for a given location was inferred to be the pre-evaporative soil water isotopic signature. This research serves as a platform for future agriculture-based ES experimental designs using water isotopes. Future work can improve upon sample collection, sample processing, and isotopic analysis methods discussed in this project. With improved methodologies, future iterations of this project can work towards refining precision irrigation practices based on new understandings of soil water storage and transport in the soil-plant-atmosphere system