Regional carbon dioxide permit trading in the United States: coalition choices for Pennsylvania

An overview is given of the growing number of regional associations in which states have entered into voluntary arrangements to limit greenhouse gas (GHG) emissions. In particular, in the Regional Greenhouse Gas Initiative (RGGI), a number of northeastern states have joined to create a regional GHG cap and trade program, beginning with the utility industry. Analysis is made of the five key issues relating to these current and potential climate action associations: the extent of the total and individual state mitigation cost-savings across all sectors from potential emission permit trading coalitions; the size of permit markets associated with the various coalitions; the relative advantages of joining various coalitions for swing states such as Pennsylvania; the implications of the exercise of market power in the permit market; and the total and individual state/country cost-savings from extending the coalition beyond US borders. It is shown that overall efficiency gains from trading with a system of flexible state caps, with greater overall cost savings increasing with increasing geographic scope.Regional Greenhouse Gas Initiative; Cap and trade program; Market power in the permit market; Mitigation costs; The size of permit market; Coalition choices for Pennsylvania

Cytological Evidence that Alternative Transposition by Ac Elements Causes Reciprocal Translocations and Inversions in Zea mays L.

McClintock discovered the first transposable element system, the Ac/Ds system in maize. She also reported that the Ac/Ds system could cause chromosome breakage and chromosome aberrations; however, the underlying mechanism was not known. Here, we recovered reciprocal translocations and inversions that were produced by alternative transposition in maize lines containing closely linked Ac transposable element termini. The cytological breakpoints of 7 reciprocal translocations and 2 pericentric inversions were determined by cytological analysis in this study

The Road to Classroom Change

Before school-based decision making can change teaching and learning for the better, we must make some changes in the reform itself

Protection of Wood from Decay Fungi by Acetylation—An Ultrastructural and Chemical Study

At acetylated weight gains of 15% or above, ultrastructural evidence of wall decomposition was lacking and hyphal cells appeared to be "starved." Blockage of action of fungal catalysts appears to be the primary protection mode of the acetylation technique. The maximum acetylation treatments inhibited consumption of wall polymers and prevented bore-hole formation. Hyphal penetration of cell walls did not proceed by mechanical forces alone; rather, the process was dependent upon chemical action in advance of hyphal tips. A comparison of colonization habits and holocellulose consumption by decay fungi in acetylated woods suggests that the activity. synthesis, or both of lignin-degrading catalysts of the white-rotter is dependent on prior or simultaneous breakdown of carbohydrates

Bifenthrin Baseline Susceptibility and Evaluation of Simulated Aerial Applications in \u3ci\u3eStriacosta albicosta\u3c/i\u3e (Lepidoptera: Noctuidae)

Striacosta albicosta (Smith) is a maize pest that has recently expanded its geographical range into the eastern United States and southeastern Canada. Aerial application of pyrethroids, such as bifenthrin, has been a major practice adopted to manage this pest. Reports of field failure of pyrethroids have increased since 2013. Striacosta albicosta populations were collected in 2016 and 2017 from maize fields in Nebraska, Kansas, and Canada and screened with bifenthrin active ingredient in larval contact dose-response bioassays. Resistance ratios estimated were generally low in 2016 (1.04- to 1.32-fold) with the highest LC50 in North Platte, NE (66.10 ng/cm2) and lowest in Scottsbluff, NE (50.10 ng/cm2). In 2017, O’Neill, NE showed the highest LC50 (100.66 ng/cm2) and Delhi, Canada exhibited the lowest (6.33 ng/cm2), resulting in a resistance ratio variation of 6.02- to 15.90-fold. Implications of bifenthrin resistance levels were further investigated by aerial application simulations. Experiments were conducted with a spray chamber where representative S. albicosta populations were exposed to labeled rates of a commercial bifenthrin formulation. Experiments resulted in 100% mortality for all populations, instars, insecticide rates, and carrier volumes, suggesting that levels of resistance estimated for bifenthrin active ingredient did not seem to impact the efficacy of the correspondent commercial product under controlled conditions. Results obtained from this research indicate that control failures reported in Nebraska could be associated with factors other than insecticide resistance, such as issues with the application technique, environmental conditions during and/or after application, or the insect’s natural behavior. Data generated will assist future S. albicosta resistance management programs

Completion of the Long Duration Wear Test of the NASA HERMeS Hall Thruster

The NASA Hall Effect Rocket with Magnetic Shielding (HERMeS) 12.5-kW Hall thruster has been the subject of extensive technology maturation by NASA GRC and JPL in preparation for development into a flight propulsion system. As part of this effort, a series of wear tests have been conducted to identify erosion phenomena and the accompanying failure modes as well as to validate service-life models for magnetically-shielded thrusters. This work presents a summary of the results obtained during the Long Duration Wear Test (LDWT), which was the third in this wear test series. The LDWT accumulated approximately 3,570 hours of operation and had the overall goal to identify and correct design or facility issues prior to the flight qualification campaign. Thruster performance, stability, and plume properties were invariant throughout the duration of the LDWT and consistent with measurements acquired during previous HERMeS performance and wear characterizations. Average erosion rates of a carbon-carbon composite pole cover were found to match those measured with graphite to within the empirical uncertainty while the previously observed time-dependence of pole cover erosion rates was linked to changes in pole cover roughness. Azimuthal variations in keeper wear rate were observed including deposition on one of the azimuthal-facing sides of the keeper mask. This strongly suggests the presence of an azimuthal component in the process driving keeper erosion