595 research outputs found
Habitat Associations of Macro-Staphylinids (Coleoptera: Staphylinidae) at Alice L. Kibbe Life Science Station, Hancock County, Illinois
Habitat associations of size-selected (≥ 5 mm length) rove beetles (Coleoptera: Staphylinidae), hereafter referred to as “macro-staphylinids,” were studied in west-central Illinois forest and prairie habitats in 2005 using pitfall traps. Habitats sampled included oak-hickory forest last burned in spring 2004, oak-hickory forest burned in spring 2005, oak-hickory forest unburned for 5+ years, unburned early successional forest, reconstructed prairie last burned in spring 2004, and reconstructed prairie burned in spring 2005. A total of 361 macrostaphylinids, representing 12 species, were collected, with Philonthus caerulipennis (Mannerheim), Platydracus maculosus (Gravenhorst), Platydracus fossator Gravenhorst, Platydracus zonatus (Gravenhorst), and Tachinus fimbriatus Gravenhorst comprising 94% of all macro-staphylinids collected. Fewest numbers of macro-staphylinids were collected in prairie habitats, particularly the prairie burned in spring 2005. A multi-response permutation procedure revealed significant variation in species composition among habitats, with relatively large differences between burned and unburned forest habitats and between forest and prairie habitats. Within-habitat variation in species composition was relatively high in the prairie and recently burned forest habitats. Indicator species analysis revealed a significant association of Philonthus asper Horn with the early successional forest, and four species had relatively high indicator values for multiple forest habitats, with fire playing a potentially important role in some cases. More intensive sampling and larger sample sizes are needed to clarify these potential habitat associations
Effects of Pitfall Trap Preservative on Collections of Carabid Beetles (Coleoptera: Carabidae)
Effects of six pitfall trap preservatives (5% acetic acid solution, distilled water, 70% ethanol, 50% ethylene glycol solution, 50% propylene glycol solution, and 10% saline solution) on collections of carabid beetles (Coleoptera: Carabidae) were studied in a west-central Illinois deciduous forest from May to October 2005. A total of 819 carabids, representing 33 species and 19 genera, were collected. Saline produced significantly fewer captures than did acetic acid, ethanol, ethylene glycol, and propylene glycol, while distilled water produced significantly fewer captures than did acetic acid. Significant associations between numbers of captures and treatment were seen in four species: Amphasia interstitialis (Say), Calathus opaculus LeConte, Chlaenius nemoralis Say, and Cyclotrachelus sodalis (LeConte). Results of this study suggest that type of preservative used can have substantial effects on abundance and species composition of carabids collected in pitfall traps
Variation in Diel Activity of Ground Beetles (Coleoptera: Carabidae) Associated With a Soybean Field and Coal Mine Remnant
Diel activities of carabids (Coleoptera: Carabidae) associated with a coal mine remnant and surrounding soybean field were studied in west-central Illinois from June through October 2002. A total of 1,402 carabids, representing 29 species and 17 genera, were collected using pitfall traps. Poecilus chalcites (Say) demonstrated roughly equal diurnal and nocturnal activity in June, but greater diurnal activity thereafter. Pterostichus permundus (Say), Cyclotrachelus seximpressus (LeConte), Amara obesa (Say), and Scarites quadriceps Chaudoir showed significant nocturnal activity. Associations between habitat and diel activity were found for three species: P. chalcites associated with the remnant and edge habitats showed greater diurnal activity than those associated with the soybean field; C. seximpressus was most active diurnally in the remnant, and Harpalus pensylvanicus (DeGeer) showed the greatest nocturnal activity in the remnant and edge habitats. We found significant temporal and habitat-related variation in diel activity among carabid species inhabiting agricultural areas in west-central Illinois
[Rezension zu:] Steffen Martus, Carlos Spoerhase: Praxeologie der Literaturwissenschaft
Rezension zu Steffen Martus/Carlos Spoerhase: Praxeologie der Literaturwissenschaft. In: Geschichte der Germanistik 35/36, 200
Low-energy structures of zinc borohydride Zn(BH)
We present a systematic study of the low-energy structures of zinc
borohydride, a crystalline material proposed for the hydrogen storage purpose.
In addition to the previously proposed structures, many new low-energy
structures of zinc borohydride are found by utilizing the minima-hopping
method. We identify a new dynamically stable structure which belongs to the
space group as the most stable phase of zinc borohydride at low
temperatures. A low transition barrier between and , the two
lowest-lying phases of zinc borohydride is predicted, implying that a
coexistence of low-lying phases of zinc borohydride is possible at ambient
conditions. An analysis based on the simulated X-ray diffraction pattern
reveals that the structure exhibits the same major features as the
experimentally synthesized zinc borohydride samples.Comment: Version accepted by Phys. Rev. B. Manuscript has 8 pages, 5 figures,
2 tables (with 6 pages, 5 figures, 2 tables in supplemental material
The application of Heat Capacity Mapping Mission (HCMM) thermal data to snow hydrology
The application of HCMM thermal infrared data to snow hydrology and the prediction of snowmelt runoff was evaluated. Data for the Salt Verde watershed in central Arizona and the southern Sierra Nevada in California were analyzed and compared to LANDSAT and NOAA satellite data, U-2 thermal data, and other correlative data. It was determined that HCMM thermal imagery provides data as accurate for snow mapping as does visible imagery, and that in comparison with the reslution of other satellite imagery, it may be the most useful. Data from the HCMM thermal channel, with careful calibration, provides useful snow surface temperature data for hydrological purposes. An approach to an automated method of analysis is presented
Estimation of the geophysical properties of the ocean surface using aircraft microwave measurements
An improved model of the effects of sea state on microwave signature has been developed which incorporates the different effects of whitecaps and streaks to define the response of microwave channels to wind speed. This model has been demonstrated to agree with recent measurements. An approximation model has also been incorporated to describe the effects of precipitation on microwave radiation through a computationally rapid routine. The use of these models and a new technique to allow the selection of the most climatologically appropriate D-matrix is demonstrated in the inversion of data collected over the bering Sea. Surface wind speed agrees very well with observations while good results are obtained for integrated water vapor, and liquid water
Studies in the use of cloud type statistics in mission simulation
A study to further improve NASA's global cloud statistics for mission simulation is reported. Regional homogeneity in cloud types was examined; most of the original region boundaries defined for cloud cover amount in previous studies were supported by the statistics on cloud types and the number of cloud layers. Conditionality in cloud statistics was also examined with special emphasis on temporal and spatial dependencies, and cloud type interdependence. Temporal conditionality was found up to 12 hours, and spatial conditionality up to 200 miles; the diurnal cycle in convective cloudiness was clearly evident. As expected, the joint occurrence of different cloud types reflected the dynamic processes which form the clouds. Other phases of the study improved the cloud type statistics for several region and proposed a mission simulation scheme combining the 4-dimensional atmospheric model, sponsored by MSFC, with the global cloud model
Low-Energy Polymeric Phases of Alanates
Low-energy structures of alanates are currently known to be described by
patterns of isolated, nearly ideal tetrahedral [AlH] anions and metal
cations. We discover that the novel polymeric motif recently proposed for
LiAlH plays a dominant role in a series of alanates, including LiAlH,
NaAlH, KAlH, Mg(AlH), Ca(AlH) and Sr(AlH). In
particular, most of the low-energy structures discovered for the whole series
are characterized by networks of corner-sharing [AlH] octahedra, forming
wires and/or planes throughout the materials. Finally, for Mg(AlH) and
Sr(AlH), we identify two polymeric phases to be lowest in energy at low
temperatures.Comment: 9 pages, 8 figures, 2 tables, including supplemental materia
Property management strategies for institutional investors in the '90s
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1996.Includes bibliographical references (leaves 91-92).by John A. Willand.M.S
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