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Objectives: Assessment and identification of spatial structures in the distribution and abundance of invasive species is important for unraveling the underlying ecological processes. The invasive agricultural insect pest Halyomorpha halys that causes severe economic losses in the United States is currently expanding both within United States and across Europe. We examined the drivers of H. halys invasion by characterizing the distribution and abundance patterns of H. halys and native stink bugs (Chinavia hilaris and Euschistus servus) across eight different spatial scales. We then quantified the interactive and individual influences of temperature, and measures of resource availability and distance from source populations, and their relevant spatial scales. We used Moran’s Eigenvector Maps based on Gabriel graph framework to quantify spatial relationships among the soybean fields in mid-Atlantic Unites States surveyed for stink bugs. Findings: Results from the multi-spatial scale, multivariate analyses showed that temperature and its interaction with resource availability and distance from source populations structures the patterns in H. halys at very broad spatial scale. H. halys abundance decreased with increasing average June temperature and distance from source population. H. halys were not recorded at fields with average June temperature higher than 23.5°C. In parts with suitable climate, high H. halys abundance was positively associated with percentage developed open area and percentage deciduous forests at 250m scale. Broad scale patterns in native stink bugs were positively associated with increasing forest cover and, in contrast to the invasive H. halys, increasing mean July temperature. Our results identify the contrasting role of temperature in structuring regional patterns in H. halys and native stink bugs, while demonstrating its interaction with resource availability and distance from source populations for structuring H. halys patterns. Conclusion: These results help predicting the pest potential of H. halys and vulnerability of agricultural systems at various regions, given the climatic conditions, and its interaction with resource availability and distance from source populations. Monitoring and control efforts within parts of the United States and Europe with more suitable climate could focus in areas of peri-urban developments with deciduous forests and other host plants, along with efforts to reduce propagule pressure. [ABSTRACT FROM AUTHOR]

The global trends for the rapid growth of distributed solar heat and power in the last decade will likely continue as the levelized cost of production for these technologies continues to decline. To be able to compare the economic potential of solar technologies one must first quantify the types and amount of solar resource that each technology can utilize; second, estimate the technological performance potential based on that resource; and third, compare the costs of each technology across regions. In this analysis, we have performed the first two steps in this process. We use physical and empirically validated models of a total of 8 representative solar system types: non-tracking photovoltaics, 2d-tracking photovoltaics, high concentration photovoltaics, flat-plate thermal, evacuated tube thermal, concentrating trough thermal, concentrating solar combined heat and power, and hybrid concentrating photovoltaic/thermal. These models are integrated into a simulation that uses typical meteorological year weather data to create a yearly time series of heat and electricity production for each system over 12,846 locations in Europe and 1,020 locations in the United States. Through this simulation, systems composed of various permutations of collector-types and technologies can be compared geospatially and temporally in terms of their typical production in each location. For example, we see that silicon solar cells show a significant advantage in yearly electricity production over thin-film cells in the colder climatic regions, but that advantage is lessened in regions that have high average irradiance. In general, the results lead to the conclusion that comparing solar technologies across technology classes simply on cost per peak watt, as is usually done, misses these often significant regional differences in annual performance. These results have implications for both solar power development and energy systems modeling of future pathways of the electricity system. [ABSTRACT FROM AUTHOR]

The continued downward spiral of enrolment in physical sciences in the USA and Europe has science educators concerned on both sides of the Atlantic. Physics has been particularly hard-hit, with the percentage of students choosing to major in the subject at the lowest level in decades. University physics has a reputation as a difficult, abstract subject with little application to the real world and introductory physics has little impact on students' conception of the discipline. Understanding how students experience their initial exposure to physics instruction could help physics educators to make the kind of targeted curriculum changes that will bring students back to physics without compromising intellectual rigor. This study makes use of qualitative methods of interview, observation and document analysis to explore how secondary and university students experienced introductory physics laboratory instruction in the Western United States. A framework relating the academic programme, the instructors, students and their laboratory groups is proposed as a way to make sense of these complex interactions. [ABSTRACT FROM AUTHOR]

This article reports that researchers around the globe fear that if U.S. particle physics withers, so will the entire field. At the same time, the U.S. Department of Energy (DOE) asked physicists to consider which of two existing particle colliders they would rather shut down early to save money. Physicists got a shock in February, when DOE nixed BTeV, a $140 million experiment that would have run at the Fermi National Accelerator Laboratory in Batavia, Illinois. Using beams from Fermilab's Tevatron collider, BTeV would have studied bottom quarks, heavier, unstable cousins of the down quarks found in protons and neutrons. BTeV researchers were expecting to get the final go-ahead for construction. Meanwhile, researchers in Europe are assembling the Large Hadron Collider at CERN, the particle physics laboratory near Geneva, Switzerland. Scheduled to start up in 2007, the $7.7 billion machine might produce the long-sought Higgs boson, the particle thought to give others their mass. But particle physicists from Europe and Asia aren't celebrating the passing of the torch from the United States.