Evaluating multiple causes of persistent low microwave backscatter from Amazon forests after the 2005 drought

Amazonia has experienced large-scale regional droughts that affect forest productivity and biomass stocks. Space-borne remote sensing provides basin-wide data on impacts of meteorological anomalies, an important complement to relatively limited ground observations across the Amazon’s vast and remote humid tropical forests. Morning overpass QuikScat Ku-band microwave backscatter from the forest canopy was anomalously low during the 2005 drought, relative to the full instrument record of 1999–2009, and low morning backscatter persisted for 2006–2009, after which the instrument failed. The persistent low backscatter has been suggested to be indicative of increased forest vulnerability to future drought. To better ascribe the cause of the low post-drought backscatter, we analyzed multiyear, gridded remote sensing data sets of precipitation, land surface temperature, forest cover and forest cover loss, and microwave backscatter over the 2005 drought region in the southwestern Amazon Basin (4°-12°S, 66°-76°W) and in adjacent 8°x10° regions to the north and east. We found moderate to weak correlations with the spatial distribution of persistent low backscatter for variables related to three groups of forest impacts: the 2005 drought itself, loss of forest cover, and warmer and drier dry seasons in the post-drought vs. the pre-drought years. However, these variables explained only about one quarter of the variability in depressed backscatter across the southwestern drought region. Our findings indicate that drought impact is a complex phenomenon and that better understanding can only come from more extensive ground data and/or analysis of frequent, spatially-comprehensive, high-resolution data or imagery before and after droughts

Multilocus sequence identification of penicillium species in cork bark during plank preparation for the manufacture of stoppers

Despite several studies reporting Penicillium as one of the most frequent fungal genera in cork planks, the isolates were rarely identified to species level.We conducted a detailed study to identify Penicillium species from the field to the factory environment prior to and after boiling the cork planks. A total of 84 samples were analyzed. Of the 486 Penicillium isolates phenotypically identified, 32 representative or unusual strains were selected for identification by multilocus DNA sequence type. Cork proved to be a rich source of Penicillium biodiversity. A total of 30 taxa were recognized from cork including rarely seen species and 6 phylogenetically unique groups. Spores of some species lodged deep in cork can survive the boiling process. P. glabrum, P. glandicola and P. toxicarium, species with high CFU numbers in the field, are still frequently present in cork after boiling. Other species are killed by the boiling treatment and replaced by Penicillium species originating from the factory environment. Species known to contribute to cork taint were isolated at all stages. Good manufacturing practices are necessary at all stages in the preparation of cork planks to minimize the load of Penicillium species that produce cork taint.CTCOR.Fundação para a Ciência e a Tecnologia (FCT

Analytical and Experimental Evaluation of Aerodynamic Thrust Vectoring on an Aerospike Nozzle

Results from numerical and cold-flow experimental investigations of aerodynamic thrust vectoring on a small-scale aerospike thruster are presented. Thrust vectoring was created by the injection of a secondary fluid into the primary flow field normal to the nozzle axis. The experimental aerospike nozzle was truncated at 57% of its full theoretical length. Data derived from cold-flow thrust vectoring tests with carbon dioxide as the working fluid are presented. Injection points near the end of the truncated spike produced the highest force amplification factors. Explanations are given for this phenomenon. For secondary injection near the end of the aerospike, side force amplification factors up to approximately 1.4 and side force specific impulses up to approximately 55 s with main flow specific impulses clustering around 38 s were demonstrated. These forces crisply reproduce input pulses with a high degree of fidelity. The side force levels are approximately 2.7% of the total thrust level at maximum effectiveness. Higher side forces on the order of 4.7% of axial thrust were also achieved at reduced efficiency. The side force amplification factors were independent of operating nozzle pressure ratio for the range of chamber pressures used in this test series

What Can Open Access Do for Me? Personal Perspectives of KU Faculty

Four University of Kansas faculty presented as panelists during this event. Slides from their presentations are shared here

Finding character strengths through loss: an extension of Peterson and Seligman (2003)

People can experience positive changes even in the midst of adversity and loss. We investigated character strengths following three recent shooting tragedies. Using an Internet database of respondents to the Values in Action Inventory of Strengths (VIA-IS), we compared responses from three groups of participants (N = 31,429) within close proximity of each event: those who completed it eight months prior to the event, and one month and two months after. Results suggested that for one of the events, participants who completed the VIA-IS after the event showed slightly different levels of self-reported character strengths compared to participants who completed the VIA-IS before the event, with some mean levels higher and others lower. The observed differences in character strengths were inconsistent across follow-up periods, and effect sizes were small (d values from –0.13 to 0.15). These findings raise questions about whether and how tragedies might catalyze differences in character strengths