3,384 research outputs found
A Milliped New to Michigan (Pselaphognatha: Polyxenus)
The authors wish to report the finding of representatives of the genus Polyxenus for the first time in Michigan (Fig. 1). In Bert M. Johnson\u27s survey (1954) of the millipedes of Michigan, no members of the subclass Pselaphognatha were reported.
During the period of September through October 1970, the authors collected over 40 specimens of Polyxenus and observed over 100 in the field. All of the specimens were found in a mature pine stand in Ypsilanti Township
Evaluation of existing and new methods of tracking glacier terminus change
ACKNOWLEDGEMENTS The authors thank two anonymous reviewers for constructive comments that helped to improve the manuscript. This research was financially supported by J.M.L.âs PhD funding from UK Natural Environment Research Council grant No. NE/I528742/1.Peer reviewedPublisher PD
Objectives and Progress on Integrated Vehicle Ground Vibration Testing for the Ares Launch Vehicles
As NASA begins design and development of the Ares launch vehicles to replace the Space Shuttle and explore beyond low Earth orbit, Integrated Vehicle Ground Vibration Testing (IVGVT) will be a vital component of ensuring that those vehicles can perform the missions assigned to them. A ground vibration test (GVT) is intended to measure by test the fundamental dynamic characteristics of launch vehicles during various phases of flight. During the series of tests, properties such as natural frequencies, mode shapes, and transfer functions are measured directly. This data is then used to calibrate loads and control systems analysis models for verifying analyses of the launch vehicle. The Ares Flight & Integrated Test Office (FITO) will be conducting IVGVT for the Ares I crew launch vehicle at Marshall Space Flight Center (MSFC) from 2011 to 2012 using the venerable Test Stand (TS) 4550, which supported similar tests for the Saturn V and Space Shuttle vehicle stacks
Morphological and molecular characterization of Isospora neochmiae n. sp. in a captive-bred red-browed finch (Neochmia temporalis) (Latham, 1802)
A new Isospora (Apicomplexa: Eimeriidae) species is described from a single red-browed finch (Neochmia temporalis) (subspecies N. temporalis temporalis), that was part of a captive population in Western Australia. Sporulated oocysts of this isolate are spherical, 18.3 (18.2-18.9) Ă 18.2 (18.2-18.6) ÎŒm, with a shape index (length/width) of 1.0; and a smooth and bilayered oocyst wall, 1.2 ÎŒm thick (outer layer 0.9 ÎŒm, inner 0.3 ÎŒm). A polar granule is present, but the oocyst residuum and a micropyle are absent. The sporocysts are ovoid-shaped, 13.3 (9.5-16.4) Ă 8.6 (6.8-10.0) ÎŒm, with a shape index of 1.5. An indistinct Stieda body is present, but the substieda body is absent. A sporocyst residuum is present and composed of numerous granules of different size scattered among the sporozoites. Morphologically, the oocysts from this isolate are different from those of all known valid Isospora spp. Molecular analysis was conducted at 4 loci; the 18S and 28S ribosomal RNA (rRNA), the mitochondrial cytochrome oxidase (COI) gene and the heat shock protein 70 (hsp70) gene. At the 18S locus, this new isolate exhibited 99.9%, 99.8%, 99.7%, and 99.5% similarity to I. sp. MAH-2013a from a superb starling (Lamprotornis superbus), I. MS-2003 from a Southern cape sparrow (Passer melanurus), I. sp. Tokyo from a domestic pigeon (Columba livia domestica) and I. MS-2003 from a Surinam crested oropendula (Psarocolius decumanus). At the 28S locus, this new isolate exhibited 99.7% similarity to both an Isospora sp (MS-2003) from a Northern house sparrow (Passer domesticus) and an Isospora sp. (MS-2003) from a Southern cape sparrow. At the COI locus, this new isolate exhibited 98.9% similarity to an Isospora sp. ex Apodemus flavicollis. At the hsp70 locus, this new isolate exhibited 99% similarity to isolate MS-2003 (. AY283879) from a wattled starling (Creatophora cinerea). Based on morphological and molecular data, this isolate is a new species of Isospora, which is named Isospora neochmiae n. sp. after its host, the red-browed finch (Neochmia temporalis)
Analyzing large-scale conservation interventions with Bayesian hierarchical models: a case study of supplementing threatened Pacific salmon.
Myriad human activities increasingly threaten the existence of many species. A variety of conservation interventions such as habitat restoration, protected areas, and captive breeding have been used to prevent extinctions. Evaluating the effectiveness of these interventions requires appropriate statistical methods, given the quantity and quality of available data. Historically, analysis of variance has been used with some form of predetermined before-after control-impact design to estimate the effects of large-scale experiments or conservation interventions. However, ad hoc retrospective study designs or the presence of random effects at multiple scales may preclude the use of these tools. We evaluated the effects of a large-scale supplementation program on the density of adult Chinook salmon Oncorhynchus tshawytscha from the Snake River basin in the northwestern United States currently listed under the U.S. Endangered Species Act. We analyzed 43Â years of data from 22 populations, accounting for random effects across time and space using a form of Bayesian hierarchical time-series model common in analyses of financial markets. We found that varying degrees of supplementation over a period of 25Â years increased the density of natural-origin adults, on average, by 0-8% relative to nonsupplementation years. Thirty-nine of the 43Â year effects were at least two times larger in magnitude than the mean supplementation effect, suggesting common environmental variables play a more important role in driving interannual variability in adult density. Additional residual variation in density varied considerably across the region, but there was no systematic difference between supplemented and reference populations. Our results demonstrate the power of hierarchical Bayesian models to detect the diffuse effects of management interventions and to quantitatively describe the variability of intervention success. Nevertheless, our study could not address whether ecological factors (e.g., competition) were more important than genetic considerations (e.g., inbreeding depression) in determining the response to supplementation
Morphological and molecular characterization of Eimeria purpureicephali n. sp. (Apicomplexa:Eimeriidae) in a red-capped parrot (Purpureicephalus spurius, Kuhl, 1820) in Western Australia
A new Eimeria species is described from a red-capped parrot (Purpureicephalus spurius). Sporulated oocysts (n = 31) were spherical to subspherical, with a rough bilayered oocyst wall 0.8 ÎŒm thick. Oocysts measured 24.0 Ă 22.8 (20.4â26.4 Ă 18.3â25.9) ÎŒm, oocyst length/width ratio, 1.10. Oocyst residuum, polar granule and micropyle were absent. Sporocysts are elongate-ovoid, 11.0 Ă 7.3 (12.7â9.2 Ă 7.9â6.6) ÎŒm, sporocyst length/width ratio, 1.51 (1.33â1.71). The thin convex Stieda body and indistinct substieda bodies were present and the sporocyst residuum was composed of numerous small granules less than 1.0 ÎŒm in diameter dispersed randomly. Each sporocyst contained 2 sausage-shaped sporozoites in head-to-tail arrangement. The sporozoite nuclei were located centrally surrounded by refractile bodies. Molecular analysis was conducted at two loci; the 18S ribosomal RNA gene and the cytochrome c oxidase subunit I gene. At the18S locus, the new isolate shared 99.0% genetic similarity with Eimeria dispersa and Eimeria innocua from the turkey. At the cytochrome c oxidase subunit I gene locus, this new isolate was most closely related to E. dispersa and E. innocua, presented 99.0% and 98.0% genetic similarity, respectively. This new isolate and E. dispersa grouped together in the same clade. Based on the morphological and molecular data, this isolate is a new species of coccidian parasite, which is named Eimeria purpureicephali n. sp. after its host, the red-capped parrot (Purpureicephalus spurius)
Instrument Bias Correction With Machine Learning Algorithms: Application to Field-Portable Mass Spectrometry
In situ sensors for environmental chemistry promise more thorough observations, which are necessary for high confidence predictions in earth systems science. However, these can be a challenge to interpret because the sensors are strongly influenced by temperature, humidity, pressure, or other secondary environmental conditions that are not of direct interest. We present a comparison of two statistical learning methodsâa generalized additive model and a long short-term memory neural network model for bias correction of in situ sensor data. We discuss their performance and tradeoffs when the two bias correction methods are applied to data from submersible and shipboard mass spectrometers. Both instruments measure the most abundant gases dissolved in water and can be used to reconstruct biochemical metabolisms, including those that regulate atmospheric carbon dioxide. Both models demonstrate a high degree of skill at correcting for instrument bias using correlated environmental measurements; the difference in their respective performance is less than 1% in terms of root mean squared error. Overall, the long short-term memory bias correction produced an error of 5% for O2 and 8.5% for CO2 when compared against independent membrane DO and laser spectrometer instruments. This represents a predictive accuracy of 92â95% for both gases. It is apparent that the most important factor in a skillful bias correction is the measurement of the secondary environmental conditions that are likely to correlate with the instrument bias. These statistical learning methods are extremely flexible and permit the inclusion of nearly an infinite number of correlates in finding the best bias correction solution
Glare, a GIS tool to reconstruct the 3D surface of palaeoglaciers
Acknowledgements This research has been supported by the Leverhulme Trust International Network Grant IN-2012-140. Processing and collecting of ground penetrating data in Forgefonna was part of Elend FĂžrre's master's project that was completed in 2009 at the Department of Geography, University of Bergen. We also acknowledge Dr Andreas Bauder for providing the subglacial topography data for Griessgletscher and Simone Tarquini for granting access to the high resolution TIN of Italy, a cut of which is provided to the reader to practice the tools (see Appendix). Referees Dr. Iestyn Barr, Dr. Jeremy Ely and Dr. Marc Oliva are thanked for their constructive comments and tool testing, which significantly improved the final output.Peer reviewedPostprin
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