Lunar base mission technology issues and orbital demonstration requirements on space station

The International Space Station has been the object of considerable design, redesign, and alteration since it was originally proposed in early 1984. In the intervening years the station has slowly evolved to a specific design that was thoroughly reviewed by a large agency-wide Critical Evaluation Task Force (CETF). As space station designs continue to evolve, studies must be conducted to determine the suitability of the current design for some of the primary purposes for which the station will be used. This paper concentrates on the technology requirements and issues, the on-orbit demonstration and verification program, and the space station focused support required prior to the establishment of a permanently manned lunar base as identified in the National Commission on Space report. Technology issues associated with the on-orbit assembly and processing of the lunar vehicle flight elements are also discussed

Technology development, demonstration, and orbital support requirements for manned lunar and Mars missions

An overview of the critical technology needs and the Space Station Freedom (SSF) focused support requirements for the Office of Exploration's (OEXP) manned lunar and Mars missions is presented. Major emphasis is directed at the technology needs associated with the low earth orbit (LEO) transportation node assembly and vehicle processing functions required by the lunar and Mars mission flight elements. The key technology areas identified as crucial to support the LEO node function include in-space assembly and construction, in-space vehicle processing and refurbishment, space storable cryogenics, and autonomous rendezvous and docking

Factors influencing adoption of conservation tillage in Australian cropping regions

The purpose of this research is to improve understanding of conservation tillage adoption decisions by identifying key biophysical and socio-economic factors influencing no-till adoption by grain growers across four Australian cropping regions. The study is based on interviews with 384 grain growers using a questionnaire aimed at eliciting perceptions relating to a range of possible long- and short-term agronomic interactions associated with the relative economic advantage of shifting to a no-tillage cropping system. Together with other farm and farmer-specific variables, a dichotomous logistic regression analysis was used to identify opportunities for research and extension to facilitate more rapid adoption decisions. The broader systems approach to considering conservation tillage adoption identified important determinants of adoption not associated with soil conservation and erosion prevention benefits. Most growers recognised the erosion-reducing benefits of no-till but it was not an important factor in explaining whether a grower was an adopter or non-adopter. Perceptions associated with shorter-term crop production benefits under no-till, such as the relative effectiveness of pre-emergent herbicides and the ability to sow crops earlier on less rainfall were influential. Employment of a consultant and increased attendance of cropping extension activities were strongly associated with no-till adoption, confirming the information and learning-intensive nature of adopting no-till cropping systems.adoption, conservation tillage, herbicide resistance, no-till, perceptions, weed management, Farm Management,

Social Costs of Herbicide Resistance: The Case of Resistance to Glyphosate

Unlike in the pesticide and antibiotic resistance literature, potential social costs and externalities associated with herbicide resistance have not generally been considered by economists. The economics of managing herbicide resistance in weeds has focused on cost-effective responses by growers to the development of resistance at the individual farm and field level. Economic analyses of optimal herbicide use have focused on optimising farmer returns in the long run. Weeds have been considered less mobile, compared to insects and diseases, suggesting that externalities resulting from resistance spread will be minimal and any consequent social costs low. Glyphosate is the world's most widely used broad-spectrum non-selective herbicide. Declining glyphosate prices, the adoption of no-till and minimum-till systems and the adoption of glyphosate-tolerant crops, have combined to cause a rapid increase in the use of glyphosate, and resistance is now appearing. In this paper we argue that the increasing possibility of widespread glyphosate resistance, exacerbated in some situations by spread through resistance mobility, presents a case where social costs associated with glyphosate resistance need to be considered when assessing optimal use of this herbicide resource at the farm level. Possible social costs associated with the loss of glyphosate efficacy include potential failure of herbicide-resistant crop systems, reduced use of conservation tillage techniques, and potentially more reliance on herbicides with greater environmental and health risks.glyphosate resistance, herbicide resistance, social costs, externalities, resistance mobility, Crop Production/Industries,

Explanation of the computer listings of Faraday factors for INTASAT users

Using a simplified form of the Appleton-Hartree formula for the phase refractive index, a relationship was obtained between the Faraday rotation angle along the angular path and the total electron content along the vertical path, intersecting the angular at the height of maximum electron density. Using the second mean value theorem of integration, the function B cosine theta second chi was removed from under the integral sign and replaced by a 'mean' value. The mean value factors were printed on the computer listing for 39 stations receiving signals from the INTASAT satellite during the specified time period. The data is presented by station and date. Graphs are included to demonstrate the variation of the Faraday factor with local time and season, with magnetic latitude, elevation and azimuth angles. Other topics discussed include a description of the bent ionospheric model, the earth's magnetic field model, and the sample computer listing

Book reviews

Teaching/Communication/Extension/Profession,

Ionospheric range-rate effects in satellite-to-satellite tracking

Investigation of ionospheric range and range-rate corrections in satellite-to-satellite tracking were investigated. Major problems were cited and the magnitude of errors that have to be considered for communications between satellites and related experiments was defined. The results point to the need of using a sophisticated modeling approach incorporating daily solar data, and where possible actual ionospheric measurements as update information, as a simple median model cannot possibly account for the complex interaction of the many variables. The findings provide a basis from which the residual errors can be estimated after ionospheric modeling is incorporated in the reduction. Simulations were performed for satellites at various heights: Apollo, Geos, and Nimbus tracked by ATS-6; and in two different geometric configurations: coplanar and perpendicular orbits

Cyanobacterial metabolites as a source of sunscreens and moisturizers: a comparison with current synthetic compounds

The recognition that ultraviolet radiation has harmful effects on the skin has led to the commercial development of inorganic and synthetic organic UV filters that can reduce the negative effects of exposure to sunlight. In addition, moisturizing chemicals are extensively used in personal care products to improve the ability of skin to retain water. Whilst current UV filter and moisturizing chemicals have clear beneficial qualities, they may also have adverse effects such as contact sensitivity, oestrogenicity and even tumorigenic effects on human skin. Furthermore, the accumulation of these chemicals in the aquatic environment could be potentially harmful. Consequently, there is interest in exploiting safer alternatives derived from biological sources, especially from photosynthetic organisms such as cyanobacteria which have developed mechanisms for coping with high UV irradiation and desiccation. In order to overcome the detrimental effects of UV radiation, these microorganisms produce UV screening compounds such as mycosporine-like amino acids and scytonemin, which are good candidates as alternatives to current synthetic UV filters. In addition, extracellular substances produced by some extremophilic species living in hyper-arid habitats have a high water retention capacity and could be used in cosmetic products as moisturizers. In this review, we present an overview of the literature describing the potential of cyanobacterial metabolites as an alternative source for sunscreens and moisturizers

Does Eccentric Hamstring Training Improve Speed and Jump Performance in Team Sports: A Systematic Review

Eccentric strength is thought to be a key component of fitness for sports requiring rapid movements such as sprinting and jumping. As a result, eccentric training forms part of strength and conditioning programmes in these sports (Krommes et al., 2017, Biomed Central Research Notes, 10(1), 669). However, the association between improvements in eccentric strength and athletic performance remains unclear. The aim of this systematic review was to determine the effect of improvements in eccentric strength on sprint and jump performance. Online databases including SPORTDiscus, CINAHL, MEDLINE, PubMed and ScienceDirect were searched (June 2017) with a date restriction (2007 – 2017) to obtain relevant articles. Search terms included eccentric hamstring training “AND” performance, speed, strength and jump performance. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to report the screening of articles. The Physiotherapy Evidence Database (PEDro) Scale was used to assess the methodological quality of each included article. A total of 8,613 articles were returned from the search. After screening the title and abstracts, 8,591 articles were excluded. Out of the remaining 25 articles, 17 were excluded after a review of full texts. A further 3 articles were identified from manually searching reference lists from which 1 was included. A total of 8 studies were included in the review. The studies included in this review were of poor methodological quality (PEDro 4.1/10). Overall, significant improvements were found in speed and jump performance for the eccentric training groups compared to the control groups. Only 2 of the studies measured strength pre and post intervention. There is weak evidence that eccentric training is effective in promoting improvements in speed and jump performance. Further high quality randomised controlled trials are needed to support the use of eccentric training to improve speed and jump performance

The Challenges of Institutionalizing Comprehensive Restorative Justice: Theory and Practice in Nova Scotia

The Nova Scotia Restorative Justice Program ( NSRJ ) is one of the oldest and by all accounts the most comprehensive in Canada. The program centres on youth justice, and operates through referrals by police, prosecutors, judges and correctional officials to community organizations which facilitate restorative conferences and other restoratively oriented processes. More than five years of NSRJ experience with thousands of cases has led to a considerable rethinking of restorative justice theory andpractice in relation to governing policies, standards for program implementation and responses to controversial issues. The purpose of this paper is to explore the significance of the Nova Scotia experience to date for sustaining restorative justice beyond the pilot project stage, where a vision of community-based justice is institutionalized with the support ofconsiderable state resources. The first part of the paper explains the genesis, structure, theoretical goals and empirical evaluation of the program to date. The second part examines some of the challenges ofinstitutionalizing comprehensive restorative justice. The paper concludes with general observations about the broader implications for restorative justice theory and practice of the Nova Scotia experience