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Alsophis antiguae
Number of Pages: 3Integrative BiologyGeological Science
Editorial: Habitat and distribution models of marine and estuarine species: Advances for a sustainable future
The physical and biological characterization of suitable habitats and species-specific models to estimate their extent are valuable for conservation and fisheries management. As exploited species and habitats face challenges from anthropogenic influences, such as fishing and climate change, the identification and protection of habitats becomes increasingly important. Most of the papers within this special topic issue used some form of species distribution model (SDM) to identify habitats used by fishes (Asch et al.; Crear et al.; Fabrizio et al.; Freidland et al.; Zydlewski et al.), marine mammals (Astarloa et al.), nearshore invertebrates (Cristiani et al.; Behan et al.), or deep-sea communities (Bowden et al.; Saunders et al.). A few papers focused on developing methods to better describe habitats (Griffin et al.; Henderson et al.; Cecino et al.), while other papers investigated model performance and incorporation of new statistical methods to improve model accuracy (Asch et al.; Behan et al.; Bowden et al.). Below we provide a synthesis of these papers under the topics of data sources used for analyses, statistical methods, stationarity and model performance, connectivity, and management implications; weconclude with a consideration of opportunities for advancing this field of stud
Along-Strike Differences in the Southern Alps of New Zealand: Consequences of Inherited Variation in Rheology
Long- and short-term strain variations along the Australian-Pacific plate boundary through the South Island of New Zealand, including a 300% increase in orogen width, coexistence of oblique thrusting on orthogonal structures, and variability in the locus of orogenic gold deposits, coincide with rheologically relevant geological variation. Our model investigates the consequences of thin, strong lower crust in the north and thick, weak lower crust in the south. Solution of the full 3-D mechanical equations reproduces the larger wavelength strain patterns of the orogen. A 3-D perturbation-based analytical solution leads to the identification of the sensitivity of displacement type to minor stress changes. Transition from boundary-normal thrusting to boundary-parallel thrusting occurs at the transition from strong to weak lower crust and is related to an increase in either tau(yz) (shear stress in the yz plane) or the ratio of the coordinate normal stresses, (sigma(yy)/sigma(xx)), where x and y are in the horizontal and z is vertical. Both mechanisms are compatible with the geologically dependent rheological variation employed in our model. Citation: Upton, P., P. O. Koons, D. Craw, C. M. Henderson, and R. Enlow (2009), Along-strike differences in the Southern Alps of New Zealand: Consequences of inherited variation in rheology, Tectonics, 28, TC2007, doi:10.1029/2008TC002353
Cellular heterogeneity of the developing worker honey bee (Apis mellifera) pupa: a single cell transcriptomics analysis
It is estimated that animals pollinate 87.5% of flowering plants worldwide and that managed honey bees (Apis mellifera) account for 30-50% of this ecosystem service to agriculture. In addition to their important role as pollinators, honey bees are well-established insect models for studying learning and memory, behaviour, caste differentiation, epigenetic mechanisms, olfactory biology, sex determination and eusociality. Despite their importance to agriculture, knowledge of honey bee biology lags behind many other livestock species. In this study we have used scRNA-Seq to map cell types to different developmental stages of the worker honey bee (prepupa at day 11 and pupa at day 15), and sought to determine their gene signatures and thereby provide potential functional annotations for as yet poorly characterized genes. To identify cell type populations we examined the cell-to-cell network based on the similarity of the single-cellsâ transcriptomic profiles. Grouping similar cells together we identified 63 different cell clusters of which 15 clusters were identifiable at both stages. To determine genes associated with specific cell populations or with a particular biological process involved in honey bee development, we used gene co-expression analysis. We combined this analysis with literature mining, the honey bee protein atlas and Gene Ontology analysis to determine cell cluster identity. Of the cell clusters identified, 9 were related to the nervous system, 7 to the fat body, 14 to the cuticle, 5 to muscle, 4 to compound eye, 2 to midgut, 2 to hemocytes and 1 to malpighian tubule/pericardial nephrocyte. To our knowledge, this is the first whole single cell atlas of honey bees at any stage of development and demonstrates the potential for further work to investigate their biology of at the cellular level
Prospects for Nonlinear Laser Diagnostics in the Jet Noise Laboratory
Two experiments were conducted to test whether optical methods, which rely on laser beam coherence, would be viable for off-body flow measurement in high-density, compressible-flow wind tunnels. These tests measured the effects of large, unsteady density gradients on laser diagnostics like laser-induced thermal acoustics (LITA). The first test was performed in the Low Speed Aeroacoustics Wind Tunnel (LSAWT) of NASA Langley Research Center's Jet Noise Laboratory (JNL). This flow facility consists of a dual-stream jet engine simulator (with electric heat and propane burners) exhausting into a simulated flight stream, reaching Mach numbers up to 0.32. A laser beam transited the LSAWT flow field and was imaged with a high-speed gated camera to measure beam steering and transverse mode distortion. A second, independent test was performed on a smaller laboratory jet (Mach number < 1.2 and mass flow rate < 0.1 kg/sec). In this test, time-averaged LITA velocimetry and thermometry were performed at the jet exit plane, where the effect of unsteady density gradients is observed on the LITA signal. Both experiments show that LITA (and other diagnostics relying on beam overlap or coherence) faces significant hurdles in the high-density, compressible, and turbulent flow environments similar to those of the JNL
Does Graded Prognostic Assessment outperform Recursive Partitioning Analysis in patients with moderate prognosis brain metastases?
AIM:
To compare the clinical utility of the Recursive Partitioning Analysis (RPA) and Graded Prognostic Assessment (GPA) in predicting outcomes for moderate prognosis patients with brain metastases.
METHODS & MATERIALS:
We reviewed 101 whole brain radiotherapy cases. RPA and GPA were calculated. Overall survival was compared.
RESULTS:
Sixty-eight patients had moderate prognosis. RPA patient characteristics for increased death hazard were â€10 WBRT fractions or no surgery/radiosurgery. GPA patients had increased death risk with no surgery/radiosurgery or lower Karnofsky Performance Status.
CONCLUSION:
The indices have similar predicted survival. Patients scored by RPA with longer radiation schedules had longer survival; patients scored by GPA did not. This indicates GPA is more clinically useful, leaving less room for subjective treatment choices
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