3,687 research outputs found
Picosecond pulse measurement by two-photon excitation of photographic film
Technique shoots two broad light beams onto a photosensitive surface which responds nonlinearly to the intensity in the beams. The resultant signal contains a component depending on the intensity correlation function between the two light beams
Thermal tuning of organic dye lasers
Non-mechanical method for tuning liquid laser wavelengths involves electrically varying temperature of laser medium. Technique is used to investigate behavior of laser dyes, and may lead to broad, tunable, light source for spectroscopy measurements of long path absorption
Culture of rectal swab specimens for enteric bacterial pathogens decreases time to test result while preserving assay sensitivity compared to bulk fecal specimens
Research on physical and physiological aspects of visual optics in space flight
Physical and physiological aspects of visual optics in space fligh
Design definition study of a NASA/Navy lift/cruise fan technology V/STOL airplane: Risk assessment addendum to the final report
An assessment of risk, in terms of delivery delays, cost overrun, and performance achievement, associated with the V/STOL technology airplane is presented. The risk is discussed in terms of weight, structure, aerodynamics, propulsion, mechanical drive, and flight controls. The analysis ensures that risks associated with the design and development of the airplane will be eliminated in the course of the program and a useful technology airplane that meets the predicted cost, schedule, and performance can be produced
Diagnostic performance of multiplex nucleic acid testing of bronchoalveolar lavage and bronchial wash specimens for respiratory viral pathogens
Draft genome sequence of the blaOXA-436- and blaNDM-1-harboring Shewanella putrefaciens SA70 isolate
ABSTRACT
We sequenced a carbapenem-resistant
Shewanella putrefaciens
isolate cultured from the sink handle of a Pakistan hospital room. Assembly annotation indicates that the isolate has a chromosomal
bla
OXA-436
carbapenemase and a plasmid-borne
bla
NDM-1
gene. To our knowledge, this is the first report of a
Shewanella
species harboring
bla
NDM
.
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The resurrection of group selection as a theory of human cooperation
Two books edited by members of the MacArthur Norms and Preferences Network (an interdisciplinary group, mainly anthropologists and economists) are reviewed here. These books in large part reflect a renewed interest in group selection
that has occurred among these researchers: they promote the theory that human cooperative behavior evolved via selective processes which favored biological and/or cultural group-level adaptations as opposed to individual-level adaptations. In support of this theory, an impressive collection of cross-cultural data are presented which suggest that participants in experimental economic games often do not behave as self-interested income maximizers; this lack of self-interest is regarded as evidence of group selection. In this review, problems with these data and with the theory are discussed. On the data side, it is argued that even if a behavior seems individually-maladaptive in a game context, there is no reason to believe that it would have been that way in ancestral contexts, since the environments of experimental games do not at all resemble those in which ancestral humans would have interacted cooperatively. And on the theory side, it is argued that it is premature to invoke group selection in order to explain human cooperation, because more parsimonious individual-level theories have not yet been exhausted. In summary, these books represent ambitious interdisciplinary contributions on an important topic, and they include unique and useful data; however, they do not make a convincing case that the evolution of human cooperation required group selection
Superficieibacter electus gen. nov., sp. nov., an extended-spectrum Ī²-lactamase possessing member of the enterobacteriaceae family, isolated from Intensive Care Unit surfaces
<p>Two Gram-negative bacilli strains, designated BP-1(T) and BP-2, were recovered from two different Intensive Care Unit surfaces during a longitudinal survey in Pakistan. Both strains were unidentified using the bioMerieux VITEK MS IVD v2.3.3 and Bruker BioTyper MALDI-TOF mass spectrometry platforms. To more precisely determine the taxonomic identity of BP-1(T) and BP-2, we employed a biochemical and phylogenomic approach. The 16S rRNA gene sequence of strain BP-1(T) had the highest identity to Citrobacter farmeri CDC 2991-81(T) (98.63%) Citrobacter amalonaticus CECT 863(T) (98.56%), Citrobacter sedlakii NBRC 105722(T) (97.74%) and Citrobacter rodentium NBRC 105723(T) (97.74%). The biochemical utilization scheme of BP-1(T) using the Analytic Profile Index for Enterobacteriaceae (API20E) indicated its enzymatic functions are unique within the Enterobacteriaceae but most closely resemble Kluyvera spp., Enterobacter cloacae and Citrobacter koseri/farmeri. Phylogenomic analysis of the shared genes between BP-1(T), BP-2 and type strains from Kluyvera, Citrobacter, Escherichia, Salmonella, Kosakonia, Siccibacter and Shigella indicate that BP-1(T) and BP-2 isolates form a distinct branch from these genera. Average Nucleotide Identity analysis indicates that BP-1(T) and BP-2 are the same species. The biochemical and phylogenomic analysis indicate strains BP-1(T) and BP-2 represent a novel species from a new genus within the Enterobacteriaceae family, for which the name Superficieibacter electus gen. nov., sp. nov., is proposed. The type strain is BP-1(T) (= ATCC BAA-2937, = NBRC 113412).</p
Strong paleoclimatic legacies in current plant functional diversity patterns across Europe
Numerous studies indicate that environmental changes during the late Quaternary have elicited longāterm disequilibria between species diversity and environment. Despite its importance for ecosystem functioning, the importance of historical environmental conditions as determinants of FD (functional diversity) remains largely unstudied. We quantified the geographic distributions of plant FD (richness and dispersion) across Europe using distribution and functional trait information for 2702 plant species. We then compared the importance of historical and contemporary factors to determine the relevance of past conditions as predictors of current plant FD in Europe. For this, we compared the strength of the relationships between FD with temperature and precipitation stability since the LGM (Last Glacial Maximum), accessibility to LGM refugia, and contemporary environmental conditions (climate, productivity, soil, topography, and land use). Functional richness and dispersion exhibited geographic patterns with strong associations to the environmental history of the region. The effect size of accessibility to LGM refugia and climate stability since the LGM was comparable to that of the contemporary predictors. Both functional richness and dispersion increased with temperature stability since the LGM and accessibility to LGM refugia. Functional richness' geographic pattern was primarily associated with accessibility to LGM refugia growing degreeādays, land use heterogeneity, diversity of soil types, and absolute minimum winter temperature. Functional dispersion's geographic pattern was primarily associated with accessibility to LGM refugia growing degreeādays and absolute minimum winter temperature. The high explained variance and model support of historical predictors are consistent with the idea that longāterm variability in environmental conditions supplements contemporary factors in shaping FD patterns at continental scales. Given the importance of FD for ecosystem functioning, future climate change may elicit not just shortāterm shifts in ecosystem functioning, but also longāterm functional disequilibria
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