TRADABLE PERMITS FOR CONTROLLING NITRATES IN GROUNDWATER AT THE FARM LEVEL: A CONCEPTUAL MODEL

Nitrate contamination of municipal and domestic well water supplies is becoming an increasing problem in many rural and urban areas, raising the cost of providing safe drinking water. The objective of this paper is to describe a marketable permit scheme that can effectively manage nitrate pollution of groundwater supplies for communities in rural areas without hindering agricultural production in watersheds. They key to implementing this scheme is being able to link nitrate leaching from nitrogen fertilizer applied to crops at a farm to nitrate levels measured at a drinking water well.agriculture, groundwater pollution, leaching, nitrates, pollution trading, Environmental Economics and Policy,

High efficiency GaAs-Ge tandem solar cells grown by MOCVD

High conversion efficiency and low weight are obviously desirable for solar cells intended for space applications. One promising structure is GaAs on Ge. The advantages of using Ge wafers as substrates include the following: they offer high efficiency by forming a two-junction tandem cell; low weight combined with superior strength allows usage of thin (3 mil) wafers; and they are a good substrate for GaAs, being lattice matched, thermal expansion matched, and available as large-area wafers

Implementation costs of a multi-component program to increase human papillomavirus (HPV) vaccination in a network of pediatric clinics

Introduction: HPV vaccination is both a clinically and cost-effective way to prevent HPV-related cancers. Increased focus on preventing HPV infection and HPV-related cancers has motivated development of strategies to increase adolescent vaccination rates. This analysis estimates the average cost associated with implementing programs aimed at increasing HPV vaccination from the perspective of the clinic decision makers. As providers and healthcare organizations consider vaccination initiatives, it is important for them to understand the costs associated with implementing these programs. Methods: Healthcare provider assessment and feedback, reminders, and education; and parent education/reminder strategies were implemented in a large pediatric clinic network between October 2015 and February 2018 to improve HPV vaccination rates. A micro-costing method was used in 2018 to prospectively estimate program implementation costs with the clinic as the unit of analysis. A sensitivity analysis assessed the effects of variability in levels of participation. Results: Assessment and feedback reports and provider education were implemented among 51 clinics at average per clinic cost of $786 and$368 respectively. Electronic vaccination reminders were delivered to providers and parents at a per clinic cost of $824. The parent education implementation cost was$2,126 per clinic. Conclusion: The four complimentary HPV evidence-based strategies were delivered at a total cost of $157,534 or$4,749 per clinic, including staff training and participant recruitment, reaching 155,000 HPV vaccine eligible adolescents

Migrating to Cloud-Native Architectures Using Microservices: An Experience Report

Migration to the cloud has been a popular topic in industry and academia in recent years. Despite many benefits that the cloud presents, such as high availability and scalability, most of the on-premise application architectures are not ready to fully exploit the benefits of this environment, and adapting them to this environment is a non-trivial task. Microservices have appeared recently as novel architectural styles that are native to the cloud. These cloud-native architectures can facilitate migrating on-premise architectures to fully benefit from the cloud environments because non-functional attributes, like scalability, are inherent in this style. The existing approaches on cloud migration does not mostly consider cloud-native architectures as their first-class citizens. As a result, the final product may not meet its primary drivers for migration. In this paper, we intend to report our experience and lessons learned in an ongoing project on migrating a monolithic on-premise software architecture to microservices. We concluded that microservices is not a one-fit-all solution as it introduces new complexities to the system, and many factors, such as distribution complexities, should be considered before adopting this style. However, if adopted in a context that needs high flexibility in terms of scalability and availability, it can deliver its promised benefits

Evaluation of sprayed & granular aphicides against the European asparagus aphid, Brachycolus asparagi (Homoptera: Aphididae) in British Columbia

A single spray of disulfoton and three of methamidophos (all at 1.12 kg ai/ha) suppressed populations of Brachycolus asparagi Mordvilko on immature asparagus for 90 days with light aphid damage. One application of oxydemeton-methyl (at 0.56 kg ai/ha) kept populations low as compared with the controls, but not low enough to prevent severe foliage damage. Two sprays of endosulfan (at 1.12 kg ai/ha) and three of malathion (at 2.24 kg ai/ha) during 90 days did not prevent moderate to heavy damage. The results indicated that the spray threshold of 0.5 B. asparagi/g of asparagus sprig used in this study was too high. No sprays controlled the other aphids present, which were mostly Myzus persicae (Sulzer). Granular formulations of disulfoton (at 0.5, 1.0, 2.0 and 4.0 kg ai/ha), carbofuran (at 2.0 kg ai/ha), and aldicarb (at 2.0 and 4.0 kg ai/ha) applied as side dressings alongside young asparagus, all gave excellent control for almost four months. CGA 73102 (at 1.0 and 2.0 kg ai/ha) and carbofuran (at 1.0 kg ai/ha) gave significant control for three months. Spray and granular treatments giving the best control also produced the thickest spears the following year

Bayes linear analysis of imprecision in computer models, with application to understanding galaxy formation.

Imprecision arises naturally in the context of computer models and their relation to reality. An imprecise treatment of general computer models is presented, illustrated with an analysis of a complex galaxy formation simulation known as Galform. The analysis involves several different types of uncertainty, one of which (the Model Discrepancy) comes directly from expert elicitation regarding the deficiencies of the model. The Model Discrepancy is therefore treated within an Imprecise framework to reflect more accurately the beliefs of the expert concerning the discrepancy between the model and reality. Due to the conceptual complexity and computationally intensive nature of such a Bayesian imprecise uncertainty analysis, Bayes Linear Methodology is employed which requires consideration of only expectations and variances of all uncertain quantities. Therefore incorporating an Imprecise treatment within a Bayes Linear analysis is shown to be relatively straightforward. The impact of an imprecise assessment on the input space of the model is determined through the use of an Implausibility measure