Valuing life detection missions

Recent discoveries imply that Early Mars was habitable for life-as-we-know-it; that Enceladus might be habitable; and that many stars have Earth-sized exoplanets whose insolation favors surface liquid water. These exciting discoveries make it more likely that spacecraft now under construction - Mars 2020, ExoMars rover, JWST, Europa Clipper - will find habitable, or formerly habitable, environments. Did these environments see life? Given finite resources (\$10bn/decade for the US ), how could we best test the hypothesis of a second origin of life? Here, we first state the case for and against flying life detection missions soon. Next, we assume that life detection missions will happen soon, and propose a framework for comparing the value of different life detection missions: Scientific value = (Reach x grasp x certainty x payoff) / \$ After discussing each term in this framework, we conclude that scientific value is maximized if life detection missions are flown as hypothesis tests. With hypothesis testing, even a nondetection is scientifically valuable.Comment: Accepted by "Astrobiology.

Developing a grid computing system for commercial-off-the-shelf simulation packages

Today simulation is becoming an increasingly pervasive technology across major business sectors. Advances in COTS Simulation Packages and Commercial Simulation Software have made it easier for users to build models, often of large complex processes. These two factors combined are to be welcomed and when used correctly can be of great benefit to organisations that make use of the technology. However, it is also the case that users hungry for answers do not always have the time, or possibly the patience, to wait for results from multiple replications and multiple experiments as standard simulation practice would demand. There is therefore a need to support this advance in the use of simulation within today’s business with improved computing technology. Grid computing has been put forward as a potential commercial solution to this requirement. To this end, Saker Solutions and the Distributed Systems Research Group at Brunel University have developed a dedicated Grid Computing System (SakerGrid) to support the deployment of simulation models across a desktop grid of PCs. The paper identifies route taken to solve this challenging issue and suggests where the future may lie for this exciting integration of two effective but underused technologies

Ocean acidification’s potential to alter global marine ecosystem services

Author Posting. © Oceanography Society, 2009. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 22 no. 4 (2009): 172-181.Ocean acidification lowers the oceanic saturation states of carbonate minerals and decreases the calcification rates of some marine organisms that provide a range of ecosystem services such as wild fishery and aquaculture harvests, coastal protection, tourism, cultural identity, and ecosystem support. Damage to marine ecosystem services by ocean acidification is likely to disproportionately affect developing nations and coastal regions, which often rely more heavily on a variety of marine-related economic and cultural activities. Losses of calcifying organisms or changes in marine food webs could significantly alter global marine harvests, which provided 110 million metric tons of food for humans and were valued at US$160 billion in 2006. Some of the countries most dependent on seafood for dietary protein include developing island nations with few agricultural alternatives. Aquaculture, especially of mollusks, may meet some of the future protein demand of economically developing, growing populations, but ocean acidification may complicate aquaculture of some species. By 2050, both population increases and changes in carbonate mineral saturation state will be greatest in low-latitude regions, multiplying the stresses on tropical marine ecosystems and societies. Identifying costeffective adaptive strategies to mitigate the costs associated with ocean acidification requires development of transferable management strategies that can be tailored to meet the specific needs of regional human and marine communities.S. Doney and S. Cooley were supported in part by a grant from the National Science Foundation (NSF ATM-0628582). H. Kite- Powell’s participation in this work was supported in part by the WHOI Marine Policy Center

Talking about a nanny nation: investigating the rhetoric framing public health debates in Australian news media

Objectives and importance of study: News media portrayal of public health issues influences public opinion, policy action and decision making. This study aimed to analyse the use of 'nanny state' frames in Australian news media coverage; identify the stakeholders invoking this frame; determine which public health-related policies attract such framing; and investigate whether 'nanny state' framing is directly challenged in news coverage. STUDY TYPE: A qualitative framing analysis. METHODS: Articles featuring the term 'nanny state' that were published in Australian print newspapers during matched periods between March and September in 2017 and 2018 were sourced through Factiva, coded and analysed for content and 'nanny state' framing. Content analysis was used to identify any public health-related issues that the terminology nanny state was applied to, and who was portrayed as imposing the nanny state. Frame analysis was used to analyse what meanings are co-presented with the phrase nanny state. RESULTS: Out of 81 print newspaper articles that included the term 'nanny state', 19% linked the term to restricting personal choice or creating dissatisfaction with too many health-related rules and regulations broadly, across a range of issues, including: bike helmets, e-cigarettes, firearm restrictions, seatbelts, pool fences and smoking bans. The next most frequent links were to regulations on alcohol (17%), road safety (14%), obesity-related issues (7%) and tobacco control (6%). Of the 81 articles, 53% appeared in news publications owned by News Corporation Australia, 20% in Fairfax Media (Nine Entertainment) publications, 17% in Daily Mail and General Trust and 10% in publications owned by other organisations. Governments were the entity most frequently framed as imposing the nanny state. Most nanny state framings (73%) were negative towards public health controls and focused on policies and regulations. Nanny state was portrayed as an assault on freedom and choice (14%) and used to attack proponents of nanny state controls (11%), while few articles framed the nanny state (7%) in a favourable light. CONCLUSIONS: 'Nanny state' is a rhetorical device commonly used in Australian news media that may contribute to discrediting of the regulation of a range of health-related issues. News Corp publications are a major propagator of nanny state rhetoric in Australian newspaper media. Public health advocates are not commonly represented within nanny state debates within the news media

An analysis of well water quality and local residents' perceptions of drinking water quality in the southern Willamette Valley

The purpose of this study was to; (1) determine the extent of well water contamination with nitrate and pesticides, and to understand the relationships among nitrate, pesticide, dissolved chloride, dissolved sulfate, well age, and well depth in the southern Willamette Valley, Oregon; and, (2) to investigate local residents' perceptions and opinions regarding water quality issues. Three data sets were used. First, the Oregon Department of Environmental Quality (ODEQ) sampled untreated well water for nitrate contamination from 500 households in the winter of 2000-2001. Second, a 100 household subset of the original 500 households was re-sampled in the summer of 2002 to be tested again for nitrate and further analyzed for pesticides, dissolved sulfate, and dissolved chloride. The third data set included responses to a mail survey from a stratified subset of residents of the original 500 households whose well water was sampled by the ODEQ. Concentrations of nitrate during the 2000-200 1 sampling period had a mean of 4.0 mg/L, and ranged from .05 to 22.6 mg/L in 476 sample wells. Concentrations exceeded the national standard of 10 mg/L in 7.4% of these samples, which increased to 9.3% in wells less than 45 ft. deep. The mean nitrate concentration for wells sampled in 2002 was 10.8 mg/L, with 48% exceeding the national standard. Eighty-one of the 100 wells tested were found to contain at least 1 pesticide. The most common pesticides found were atrazine (73% of the wells) and its breakdown product desethylatrazine (80% of the wells). No significant association was found between nitrates 2000-2001 levels and either well depth or well age. Well depth and well age were found to have a statistically significant inverse relationship. Dissolved sulfate and nitrate (2002 sampling period) were significantly associated. Nitrate concentrations were not significantly correlated with any of the other independent variables. The response rate for the surveys was 51%. Seventy-two percent of the respondents do not use a water treatment device and 28% use treatment devices. There was no difference in the use of water treatment devices based on nitrate concentrations in the well water. Respondents who used activated charcoal treatment devices had significantly lower nitrate concentrations than respondents who used reverse osmosis treatment systems. There was no significant relationship between respondents' description of well water quality and nitrate concentrations. However, respondents who did not own agricultural land were more likely than those who owned agricultural property to indicate concern over agricultural fertilizer and pesticide use harming well water quality. No significant relationship was found between nitrate contamination levels and the frequency of septic tank pumping, the distance of the septic tank from the well head, or the distance from the septic tanks drain field. Nitrate contamination levels were found to be significantly different between geologic units. Nitrate levels in geologic unit Qg₁ were significantly higher than all other geologic units, with the exception of Qalc. Typically, households located in areas where the Holocene alluvium of the Willamette River and the Pleistocene sand and gravel post-Missoula flood deposits dominated the geologic structure were at greater risk of high nitrate contamination levels

Materials Characterization at Utah State University: Facilities and Knowledgebase of Electronic Properties of Materials Applicable to Spacecraft Charging

In an effort to improve the reliability and versatility of spacecraft charging models designed to assist spacecraft designers in accommodating and mitigating the harmful effects of charging on spacecraft, the NASA Space Environments and Effects (SEE) Program has funded development of facilities at Utah State University for the measurement of the electronic properties of both conducting and insulating spacecraft materials. We present here an overview of our instrumentation and capabilities, which are particularly well suited to study electron emission as related to spacecraft charging. These measurements include electron-induced secondary and backscattered yields, spectra, and angular resolved measurements as a function of incident energy, species and angle, plus investigations of ion-induced electron yields, photoelectron yields, sample charging and dielectric breakdown. Extensive surface science characterization capabilities are also available to fully characterize the samples in situ. Our measurements for a wide array of conducting and insulating spacecraft materials have been incorporated into the SEE Charge Collector Knowledgebase as a Database of Electronic Properties of Materials Applicable to Spacecraft Charging. This Database provides an extensive compilation of electronic properties, together with parameterization of these properties in a format that can be easily used with existing spacecraft charging engineering tools and with next generation plasma, charging, and radiation models. Tabulated properties in the Database include: electron-induced secondary electron yield, backscattered yield and emitted electron spectra; He, Ar and Xe ion-induced electron yields and emitted electron spectra; photoyield and solar emittance spectra; and materials characterization including reflectivity, dielectric constant, resistivity, arcing, optical microscopy images, scanning electron micrographs, scanning tunneling microscopy images, and Auger electron spectra. Further details of the instrumentation used for insulator measurements and representative measurements of insulating spacecraft materials are provided in other Spacecraft Charging Conference presentations. The NASA Space Environments and Effects Program, the Air Force Office of Scientific Research, the Boeing Corporation, NASA Graduate Research Fellowships, and the NASA Rocky Mountain Space Grant Consortium have provided support