Understanding early Solar System processes: an oxygen isotope perspective

Oxygen isotope analysis has become an indispensable tool in the study of early Solar System processes. The high levels of precision available with the laser fluorination technique have significantly improved the range and scope of such investigations. As a result, high precision oxygen isotope measurements provide critical information about the processes that operated both in the nebula and subsequently on a diverse range of parent bodies, from small primitive asteroids to planetary-sized bodies

Results of the 1969 balloon flight solar cell standardization program

High altitude balloon flights for solar cell calibratio

Results of the 1968 balloon flight solar cell standardization program

Space power output of solar cell arrays prediction using terrestrial measurements and high altitude balloon

The management of plantar warts - a podiatric perspective

The number of treatments offered for a particular condition is often indicative of the unsatisfactory success rate in curing the problem. This can be demonstrated by the documented plethora of treatments suggested for plantar warts (or verrucae), which range from the traditional to the bizarre — including banana skins, hypnosis and nail varnish. This paper aims to review the problem of plantar warts and take an evidence-based approach, balancing research findings coupled with the authors’ combined 40 years of experience in managing this common problem

SLIP4EX- a program for routine slope stability analysis to include the effects of vegetation, reinforcement and hydrological changes

SLIP4EX is a straightforward computer program developed in connection with the EU funded ECOSLOPES project for routine stability analysis and the assessment of the contribution of vegetation to slope stability. The slope section is drawn up and dimensions and parameters are fed in to the Microsoft Excel based program for stability calculations and comparisons of Factors of Safety using different methods of analysis (Bishop, Janbu, Fellenius, Simple, Greenwood). The background and assumptions involved in the derivation of each of the methods is briefly described. The simplicity of the program enables the user to understand the nature of the analysis, explore the parameter assumptions made and compare the different methods of analysis. Soil reinforcement by geosynthetic layers or anchors, and vegetation effects of enhanced cohesion, changed water pressures, mass of vegetation, wind forces and root reinforcement forces are readily included in the analysis. The program is freely available on request from the author

Factors Affecting Water Management on the North Slope of Alaska

The North Slope of Alaska is undergoing sudden development following the recent discovery of large oil and gas reserves in the area. The water resources of the region should be carefully managed both to ensure adequate supplies of usable water at reasonable cost, and to guard against excessive deterioration of water quality. The likely effects on the environment of man's activities are investigated and found to be poorly understood at the present time. Research priorities are suggested to supply rapid answers to questions of immediate importance. The applicability of a regional management concept to the North Slope waters is considered and the concept is recommended as part of a broad land and water planning philosophy which would emphasize regional control over state and federal control. The use of economic incentives rather than standards for the control of water quality is not recommended at the present time.The work upon which this report is based was supported primarily by funds provided by the Sea Grant Program of the University of Alaska under grant No. 1-36109

Results of the 1973 NASA/JPL balloon flight solar cell calibration program

High altitude balloon flights carried 37 standard solar cells for calibration above 99.5 percent of the earth's atmosphere. The cells were assembled into standard modules with appropriate resistors to load each cell at short circuit current. Each standardized module was mounted at the apex of the balloon on a sun tracker which automatically maintained normal incidence to the sun within 1.0 deg. The balloons were launched to reach a float altitude of approximately 36.6 km two hours before solar noon and remain at float altitude for two hours beyond solar noon. Telemetered calibration data on each standard solar cell was collected and recorded on magnetic tape. At the end of each float period the solar cell payload was separated from the balloon by radio command and descended via parachute to a ground recovery crew. Standard solar cells calibrated and recovered in this manner are used as primary intensity reference standards in solar simulators and in terrestrial sunlight for evaluating the performance of other solar cells and solar arrays with similar spectral response characteristics

How Useful are High-Precision Delta ?17O Data in Defining the Asteroidal Sources of Meteorites?: Evidence from Main-Group Pallasites, Primitive and Differentiated Achondrites

High-precision oxygen isotope analysis is capable of revealing important information about the relationship between different meteorite groups. New data confirm that the main-group pallasites are from a distinct source to either the HEDs or mesosiderites

Effects of Rate of Drying, Life History Phase, and Ecotype on the Ability of the Moss Bryum Argenteum to Survive Desiccation Events and the Influence on Conservation and Selection of Material for Restoration

Desiccation stress is frequently experienced by the moss Bryum argenteum and can influence survival, propagation and niche selection. We attempted to disentangle the interacting factors of life history phase (five categories) and rate of desiccation (time allotted for induction of desiccation tolerance) for 13 ecotypes of B. argenteum. Using chlorophyll fluorescence as a stress index, we determined how these parameters influenced desiccation tolerance. Rate of drying and life phase significantly affected desiccation tolerance. The reaction norms of desiccation tolerance displayed by the 13 ecotypes showed a substantial degree of variation in phenotypic plasticity. We observed differences in survival and fluorescence between rapid and slow drying events in juveniles. These same drying applications did not produce as large of a response for adult shoots (which consistently displayed high values). Some juvenile and protonemal ecotypes, such as those from the southwest United States, possessed higher innate tolerance to rapid drying, and greater resilience compared to ecotypes sourced from mesic localities in the United States. These results show a complex nuanced response to desiccation with ecotypes displaying a range of responses to desiccation reflecting both inherently different capacities for tolerating desiccation as well as variation in capacity for phenotypic plasticity. Our results suggest that we should expect few short-term effects of climate change due to high desiccation tolerance of adult shoots, but significant adverse long-term effects on colony establishment due to low tolerance of protonema and juvenile shoots. Further, we would recommend that future studies using mosses for habitat restoration of aridlands consider the desiccation tolerance capacity of individual ecotypes used for cultivation and later re-introduction. Understanding how mosses respond to desiccation is essential to interpret ecological roles, habitat preferences, selective pressures, and responses to climate change, and to estimate the potential effects of climate changes on bryophyte species and populations