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Climate change is projected to alter the structure of plant communities due to increasing temperatures and changes to precipitation patterns, particularly in midlatitude dryland ecosystems. Modifications to climatic suitability may lead to major community changes such as altered dominant plant functional types. Previous studies have indicated that climatic suitability is likely to increase for C4 grasses and decrease for C3 grasses in the Western United States. However, if no C4 grass species currently exist to serve as a propagule source, expansion into areas of increased suitability will be limited. We conducted a field and modeling study in the Upper Green River Basin (UGRB) of Western Wyoming to determine if (1) C4 grasses are present to provide a propagule source and (2) C4 grasses are likely to increase in importance relative to C3 grasses due to climatic changes. We searched 44 sites for C4 grasses to establish presence, and modeled suitability at 35 sites using 17 Global Climate Models, two greenhouse gas Representative Concentration Pathways (RCPs; 4.5 and 8.5), and two time periods (mid‐ and late century; 2030–2060 and 2070–2099, respectively). We found C4 grasses at 10 of the 44 sites, indicating that there is a present propagule source. Our model projected increases in suitability for both C3 and C4 grasses across sites for all RCPs and time periods. In the mid‐century RCP 4.5 scenario, the C3 functional type increased in projected biomass in 29 of 35 sites, and the C4 type increased in 31 sites. In this scenario, C3 grasses increased in projected biomass by a median 4 g m−2 (5% change), and C4 grass biomass increased by a median 8 g m−2 (21% change). Our study suggests that climate change will increase climatic suitability for grasses across the UGRB, and that all requirements are in place for C4 grasses to increase in abundance. [ABSTRACT FROM AUTHOR]

Aim: Comprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW). Location: Global. Taxon All extant mammal species. Methods: Range maps were digitally interpreted, georeferenced, error‐checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species). Results: Range maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non‐commercial use. Main conclusion: Expert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad‐scale characterizations and model‐based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species‐level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control. [ABSTRACT FROM AUTHOR]

As the African climate history recorded in Kilimanjaro’s Northern Ice Field (NIF) is rapidly lost, the age of the glacier remains disputed. Current age estimates from ice core data and glacial dynamics modeling disagree by an order of magnitude (11,700 vs ~1000 years old). We present radiocarbon dates of glacial dust and proximal soil samples collected from in and around the edge of the NIF that support the hypothesis that the peripheral portions of the NIF glacier are younger and more dynamic than the center. Samples of a dust-rich ice layer, 1.5 m above the base at the edge of the ~40 m high glacier ice cliff were found to be 1600–790 years old. These dates agree with the prediction of significant growth and shrinkage in glacial coverage over the last millennium. The variation in radiocarbon ages likely arises from heterogeneity in the summit volcanic soils, the main source of the dust recovered from the glacier, and cryoconite microbial activity. Sediment samples of a supraglacial pond had modern radiocarbon ages, further demonstrating the impact of cryoconite microbial communities on radiocarbon measurements of glacial samples. After accounting for the variability in the sample ages and the effects of microbial activity, we contend that the lower (i.e. younger) limit of the radiocarbon age range is the most reliable assessment of the age of the ice in which it was trapped. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Agricultural Economics is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Puccinia psidii sensu lato (s.l.) is an invasive rust fungus threatening a wide range of plant species in the family Myrtaceae. Originating from Central and South America, it has invaded mainland USA and Hawai'i, parts of Asia and Australia. We used CLIMEX to develop a semi-mechanistic global climatic niche model based on new data on the distribution and biology of P. psidii s.l. The model was validated using independent distribution data from recently invaded areas in Australia, China and Japan. We combined this model with distribution data of its potential Myrtaceae host plant species present in Australia to identify areas and ecosystems most at risk. Myrtaceaeous species richness, threatened Myrtaceae and eucalypt plantations within the climatically suitable envelope for P. psidii s.l in Australia were mapped. Globally the model identifies climatically suitable areas for P. psidii s.l. throughout the wet tropics and sub-tropics where moist conditions with moderate temperatures prevail, and also into some cool regions with a mild Mediterranean climate. In Australia, the map of species richness of Myrtaceae within the P. psidii s.l. climatic envelope shows areas where epidemics are hypothetically more likely to be frequent and severe. These hotspots for epidemics are along the eastern coast of New South Wales, including the Sydney Basin, in the Brisbane and Cairns areas in Queensland, and in the coastal region from the south of Bunbury to Esperance in Western Australia. This new climatic niche model for P. psidii s.l. indicates a higher degree of cold tolerance; and hence a potential range that extends into higher altitudes and latitudes than has been indicated previously. The methods demonstrated here provide some insight into the impacts an invasive species might have within its climatically suited range, and can help inform biosecurity policies regarding the management of its spread and protection of valued threatened assets. [ABSTRACT FROM AUTHOR]

Some of the most appealing science targets for future exploration missions in our solar system lie in terrains that are inaccessible to state-of-the-art rover technology. This paper discusses the challenges and constraints of designing a robotic explorer for these 'extreme'' terrains and then examines the trade-offs among different mobility architectures. To address many of these challenges, we have developed the Axel family of rovers. The Axel rover is a two-wheeled tethered robot capable of rappelling down steep slopes and traversing rocky terrain. The DuAxel rover, which is a four-wheeled vehicle formed from two Axel rovers, provides untethered mobility to get to extreme terrains. We describe the basic design principles of these rovers and review our efforts to implement the key features of the Axel concept. Limitations found during experiments with prior Axel rover prototypes led to the design of a third-generation Axel rover. We describe the features of this new rover and then present a thermal analysis conducted to assess the feasibility of exploring lunar cold traps, which are expected to have a temperature range of 40 to 70 K. We conclude the paper with results showcasing Axel and DuAxel's extreme-terrain performance as evaluated during two recent field tests in a steeply sloped Southern California rock quarry and at a location in Arizona that closely resembles rugged Martian terrain. We also summarize lessons learned during the Axel development program. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

- Six large iron meteorites have been discovered in the Meridiani Planum region of Mars by the Mars Exploration Rover Opportunity in a nearly 25 km-long traverse. Herein, we review and synthesize the available data to propose that the discovery and characteristics of the six meteorites could be explained as the result of their impact into a soft and wet surface, sometime during the Noachian or the Hesperian, subsequently to be exposed at the Martian surface through differential erosion. As recorded by its sediments and chemical deposits, Meridiani has been interpreted to have undergone a watery past, including a shallow sea, a playa, an environment of fluctuating ground water, and/or an icy landscape. Meteorites could have been encased upon impact and/or subsequently buried, and kept underground for a long time, shielded from the atmosphere. The meteorites apparently underwent significant chemical weathering due to aqueous alteration, as indicated by cavernous features that suggest differential acidic corrosion removing less resistant material and softer inclusions. During the Amazonian, the almost complete disappearance of surface water and desiccation of the landscape, followed by induration of the sediments and subsequent differential erosion and degradation of Meridiani sediments, including at least 10-80 m of deflation in the last 3-3.5 Gy, would have exposed the buried meteorites. We conclude that the iron meteorites support the hypothesis that Mars once had a denser atmosphere and considerable amounts of water and/or water ice at and/or near the surface. [ABSTRACT FROM AUTHOR]

Copyright of Climate Policy (Earthscan) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Onboard Autonomous Science Investigation System has been developed to enable a rover to identify and react to serendipitous science opportunities. Using the FIDO rover in the Mars Yard at JPL, we have successfully demonstrated a fully autonomous opportunistic science system. The closed loop system tests included the rover acquiring image data, finding rocks in the image, analyzing rock properties and identifying rocks that merit further investigation. When the system on the rover alerts the rover to take additional measurements of interesting rocks, the planning and scheduling component determines if there are enough resources to meet this additional science data request. The rover is then instructed to either turn toward the rock, or to actually move closer to the rock to take an additional, close-up image. Prototype dust devil and cloud detection algorithms were delivered to an infusion task which refined the algorithms specifically for Mars Exploration Rovers (MER). These algorithms have been integrated into the MER flight software and were recently uploaded to the rovers on Mars. © 2007 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article discusses on the relevance of disability in educational practice. Intersections of experience and the pedagogy that professors with disabilities bring to the classroom are considered. Teachers with disabilities embody pedagogies of justice, interdependence, and respect for differences. Teaching disability reveals spaces in education that is often ignored. It has been found out that teachers with disability offer knowledge through their bodies and experiences which are not actually part of the curriculum.

Researchers have previously described a mobile robot, or rover, operator's difficulty in accurately perceiving the rover's tilt and roll, which can lead to rollover accidents. Safe mobile robot navigation and effective mission planning also require an operator to accurately interpret and understand the geometry and scale of features in the rover's environment. This work presents an experiment that measures an observer's ability to estimate height of distant (5-15 m) obstacles given an accurate local model (e.g., within 0-S m of the rover), a panoramic image, and a physical mock-up of the local terrain. The experimental conditions were intended to represent a best-case scenario for a stopped rover equipped with short base-line stereoscopic cameras. The participants' task was to extrapolate the well-modeled local geometry to monoscopic images of the more distant terrain. The experiment compared two estimation techniques: With the first technique, each observer physically indicated his or her direct estimates of the obstacle distance and height. With the second estimation technique, which we call horizon analysis, the observer indicated the position of the top and bottom of each rock on an image and the height was calculated by measuring the visual angle between the theoretical horizon and the points indicated by the observer. The direct estimation technique overestimated the height of the rocks by an average of 190%; the horizon analysis technique overestimated by 80%. The results suggest that even when provided with a rich set of supplementary and context in- formation, rover operators have significant difficulty in vertically perceiving the scale of distant terrain. The results also suggest that horizon analysis is a more accurate method for determining the height of distant rover navigation obstacles, when the local terrain is nearly level. [ABSTRACT FROM AUTHOR]

Three siblings, two boys and one girl, presented with pigmentary abnormalities. The brothers, ages 11 and 6 years, had diffuse reticulate macular hyperpigmentation with onset in early childhood. In addition, these boys had hypohydrosis, coarse hair with an upswept frontal hairline, failure to thrive, and chronic pulmonary disease. The older boy also had corneal dystrophy and marked photophobia. A punch biopsy specimen from the 11-year-old showed melanophages and necrotic keratinocytes. Stains for amyloid were negative. The sister, age 2 years, had congenital linear hyperpigmented patches involving the intertrigenous areas, but was otherwise normal. The clinical findings of these children were consistent with X-linked reticulate pigmentary disorder with systemic manifestations. We present a summary of the clinical manifestations of this rare disorder and discuss efforts to identify the causative gene. [ABSTRACT FROM AUTHOR]

This article explores various ideologies that shape how the human body (in particular, the disabled human body) is understood and often not addressed within theological education. Graduate schools of theology have limited experience with both the study of disability, and the presence of people with disabilities in particular, on their campuses. The absence of education about the human experience of disability represents a “missing note” in theological inquiry. The author provides an overview of critical boundaries that mark the limits and possibilities for theological inquiry about the human experience of disability. [ABSTRACT FROM PUBLISHER]

The structure of and cost allocation for optimal (cost minimizing) networks have been examined. Present network pricing systems have led to a number of inefficiencies including competing services and defection of users. Certain issues of equity are also involved in that some users, may subsidize others if uniform prices are established for an entire network. Among alternative systems for cost allocation to network users it was shown that inefficiencies are to be expected in average cost pricing, unit mile pricing, and marginal cost pricing. An additional difficulty with marginal cost pricing is that total network costs are not paid. For cost allocation based on external cost these inefficiencies are ameliorated, provided that users cannot form a coalition to obtain a lower cost to themselves outside the network. Adjusted external cost allocations, which price services to users as the least cost obtainable in any coalition of users, eliminate the problem of defections from the network. The main difficulty with this pricing method is that it is complicated; charges are not easy to compute. [ABSTRACT FROM AUTHOR]

Examines paintings as an investment over the period 1780 to 1970. Sources of demand for paintings; Factors affecting the realized price of paintings; Other factors in the determination of general and relative price levels; Information on the categories of consumption services; Analysis of the principal facets of the market for paintings.

This article examines the principal economic arguments offered in support of a federal program of recycling incentives as well as legislative proposals for its establishment in the U.S. One key argument advanced in support of recycling incentives is that tax equity should be established between recyclers and primary material producers. A second argument is that secondary materials industry may be subsidized for their part in helping reduce the environmental damages caused by primary material production. A final argument is that the existing structure of federal regulation favors primary production over secondary material recovery and should be balanced with incentives for recycling. Meanwhile, Congressional interest in augmenting the flow of recycled materials has developed on many fronts. The study of freight rate discrimination was mandated by the Railroad Revitalization and Regulatory Reform Act of 1976. Loan guarantees for facilities to recover energy from solid waste were proposed in House Resolution (HR) 1045 and tax deductions for similar facilities were proposed in HR 1046. Tax deductions or direct cash subsidies for recycling would be granted under a variety of proposals offered before the U.S. Congress such as HR 148 and HR 10612.

No abstract available for this article. [ABSTRACT FROM PUBLISHER]

No abstract available for this article. [ABSTRACT FROM PUBLISHER]

Presents information on a study which examined the impact of land use control systems on land market values, in reference to the Adirondack Park Land Use and Development Plan. Methodology; Results of the study.

Introduction: A preliminary 1:1M map of Terra Cimmeria, Mars, (5oS-40oS, 130oE-170oE) has been produced. This project’s intention was to clarify far-reaching structural effects relating to the activity of the Claritas tectonic center, thought to be the site of incipient Tharsis volcanic activity [1,2]. Obvious geomorphic expressions structurally related to Tharsis were ultimately not identified, although other regional tectonic and hydrogeological inferences were inspired by this work [3,4]. Data and methods: A THEMIS Daytime IR basemap was used, with CTX, MOLA, and HRSC overlaid for context. Mapping was performed in both Esri’s ArcMap and ArcGIS Pro. Map development: Units on this geologic map can be broadly classed into the following categories: highland, basin, crater, and northern lowlands units. These divisions agree with the global map of Tanaka and co-workers [5]. However, spatial correlation of our units with theirs is not strong, likely due to mapping resolution. Units within each class were delineated on the basis of albedo, surface texture, and topography. Specific units within the highlands and basin categories were split in situations when fluvial features appeared to incise downwards from one into another. Areally extensive fluvial fill units were also delineated. Future work: Crater count have not yet been performed. Although cross-cutting relationships are identifiable between different basin units on the basis of relative fluvial incision, the direction of the stratigraphic order of the cross-cutting basin units depends directly on the relative effects of tectonic uplift and stream power. A detailed geochronology will be forthcoming after performing counts [ABSTRACT FROM AUTHOR]

The article discusses various articles published within the issue, including one on habitus of theology and another on people with disabilities.

The article focuses on the potential impact of using modern exploration telepresence to optimize scientific research on planetary surfaces. The scientific opportunities provided by exploration telepresence include real-time vision and mobility on the planet for astronaut scientist, the faster way for Mars exploration and the control of surrogates in real time when humans are in orbit.