1,052 research outputs found
Quantitative acoustic analysis of the vocal repertoire of the golden rocket frog (\u3ci\u3eAnomaloglossus beebei\u3c/i\u3e)
This study describes the vocal repertoire of the Guyanan golden rocket frog, Anomaloglossus beebei, a bromeliad specialist with biparental care. Using multivariate analyses of nine call properties, as well as the occurrence of nonlinear phenomena, three signal types were distinguishedāadvertisement, courtship, and aggressive calls. Although all three call types were composed of a short series of rapidly repeated pulses, advertisement calls were produced at higher amplitudes and had longer pulse durations than both courtship calls and aggressive calls. Courtship calls exhibited lower dominant frequencies than both advertisement and aggressive calls, which had similar dominant frequencies. Aggressive calls had more pulses per call, had longer intervals between calls, and occasionally contained one or two introductory pulses preceding the pulsed call. Several acoustic properties predicted aspects of the signaler\u27s body size and condition. Our study demonstrates the reliability of human observers to differentiate the multiple call types of A. beebei based on hearing calls and observing the social context in which they are produced under field conditions
New views on old hands: the context of stencils in El Castillo and La Garma Caves (Cantabria, Spain)
Hand stencils are an intriguing feature of prehistoric imagery in caves and rockshelters in several parts of the world, and the recent demonstration that the oldest of those in Western Europe date back to 37 000 years or earlier further enhances their significance. Their positioning within the painted caves of France and Spain is far from random, but responds to the shapes and fissures in the cave walls. Made under conditions of low and flickering light, the authors suggest that touchāāpalpationāāas much as vision, would have driven and directed the locations chosen for these stencils. Detailed study of the images in two Cantabrian caves also allows different individuals to be distinguished, most of whom appear to have been female. Finally, the project reveals deliberate associations between the stencils and features on the cave walls
Simulations of the flocculent spiral M33: what drives the spiral structure?
We perform simulations of isolated galaxies in order to investigate the
likely origin of the spiral structure in M33. In our models, we find that
gravitational instabilities in the stars and gas are able to reproduce the
observed spiral pattern and velocity field of M33, as seen in HI, and no
interaction is required. We also find that the optimum models have high levels
of stellar feedback which create large holes similar to those observed in M33,
whilst lower levels of feedback tend to produce a large amount of small scale
structure, and undisturbed long filaments of high surface density gas, hardly
detected in the M33 disc. The gas component appears to have a significant role
in producing the structure, so if there is little feedback, both the gas and
stars organise into clear spiral arms, likely due to a lower combined
(using gas and stars), and the ready ability of cold gas to undergo spiral
shocks. By contrast models with higher feedback have weaker spiral structure,
especially in the stellar component, compared to grand design galaxies. We did
not see a large difference in the behaviour of with most of these
models, however, because stayed relatively constant unless the disc
was more strongly unstable. Our models suggest that although the stars produce
some underlying spiral structure, this is relatively weak, and the gas physics
has a considerable role in producing the large scale structure of the ISM in
flocculent spirals.Comment: 17 pages, 17 figures, accepted for publication in MNRA
An Inversion Disrupting FAM134B Is Associated with Sensory Neuropathy in the Border Collie Dog Breed
Sensory neuropathy in the Border Collie is a severe neurological disorder caused by the degeneration of sensory and, to a lesser extent, motor nerve cells with clinical signs starting between 2 and 7 months of age. Using a genome-wide association study approach with three cases and 170 breed matched controls, a suggestive locus for sensory neuropathy was identified that was followed up using a genome sequencing approach. An inversion disrupting the candidate gene FAM134B was identified. Genotyping of additional cases and controls and RNAseq analysis provided strong evidence that the inversion is causal. Evidence of cryptic splicing resulting in novel exon transcription for FAM134B was identified by RNAseq experiments. This investigation demonstrates the identification of a novel sensory neuropathy associated mutation, by mapping using a minimal set of cases and subsequent genome sequencing. Through mutation screening, it should be possible to reduce the frequency of or completely eliminate this debilitating condition from the Border Collie breed population
Electron Microscopy Of Wood Of Callixylon And Cordaites
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141638/1/ajb210693.pd
Sensitivity of Prescribing High-Intensity, Interval Training Using the Critical Power Concept
International Journal of Exercise Science 8(3): 202-212, 2015. The critical power (CP) concept enables the calculation of time to exhaustion (tLIM) for a given power output above CP using the equation of tLIM = Wā/(power ā CP), where Wā is the curvature constant, and CP is the asymptote for the power-tLIM relationship. The CP concept offers great promise for prescribing high-intensity interval training (HIIT); however, knowledge on the conceptās sensitivity is lacking (i.e., how much of a difference in Wā expenditure is needed to evoke different metabolic responses). We tested if two different power-tLIM configurations expending identical proportions of Wā would evoke different end-exercise oxygen uptake (VO2) and heart rate (HR) values. Five men and five women completed a graded exercise test, 3-min all-out exercise tests, and intervals prescribed to deplete either 70 or 80% of Wā on separate visits. Consistency statistics of intraclass correlation (ICC a), standard error of measure (SEM), and coefficient of variation (CV) were calculated on end-exercise values. End-exercise VO2 were similar for the 3.5- and 5-min bouts, depleting 70% of Wā (ICC a = 0.91, SEM = 3.23 mLĀ·kg-1Ā·min-1, CV = 8.1%) and similar for the 4- and 5-min bouts, depleting 80% of Wā (ICC a = 0.95, SEM = 2.34 mLĀ·kg-1Ā·min-1, CV = 8.1%). No VO2 differences were observed between trials or conditions (p = 0.58). Similarly, HR values (~181 bĀ·min-1) did not differ between trials or conditions (p = 0.45). Use of the CP concept for HIIT prescriptions of different power-tLIM configurations evokes similar end-exercise VO2 values on a given day. Our findings indicate that \u3e10% Wā depletion is necessary to evoke different metabolic responses to HIIT
Multi-label classification using ensembles of pruned sets
This paper presents a Pruned Sets method (PS) for multi-label classification. It is centred on the concept of treating sets of labels as single labels. This allows the classification process to inherently take into account correlations between labels. By pruning these sets, PS focuses only on the most important correlations, which reduces complexity and improves accuracy. By combining pruned sets in an ensemble scheme (EPS), new label sets can be formed to adapt to irregular or complex data. The results from experimental evaluation on a variety of multi-label datasets show that [E]PS can achieve better performance and train much faster than other multi-label methods
An intracellular motif of GLUT4 regulates fusion of GLUT4-containing vesicles
<p>Abstract</p> <p>Background</p> <p>Insulin stimulates glucose uptake by adipocytes through increasing translocation of the glucose transporter GLUT4 from an intracellular compartment to the plasma membrane. Fusion of GLUT4-containing vesicles at the cell surface is thought to involve phospholipase D activity, generating the signalling lipid phosphatidic acid, although the mechanism of action is not yet clear.</p> <p>Results</p> <p>Here we report the identification of a putative phosphatidic acid-binding motif in a GLUT4 intracellular loop. Mutation of this motif causes a decrease in the insulin-induced exposure of GLUT4 at the cell surface of 3T3-L1 adipocytes via an effect on vesicle fusion.</p> <p>Conclusion</p> <p>The potential phosphatidic acid-binding motif identified in this study is unique to GLUT4 among the sugar transporters, therefore this motif may provide a unique mechanism for regulating insulin-induced translocation by phospholipase D signalling.</p
Constraining a Historical Black Carbon Emission Inventory of the United States for 1960ā2000
We present an observationally constrained United States black carbon emission inventory with explicit representation of activity and technology between 1960 and 2000. We compare measured coefficient of haze data in California and New Jersey between 1965 and 2000 with predicted concentration trends and attribute discrepancies between observations and predicted concentrations among several sources based on seasonal and weekly patterns in observations. Emission factors for sources with distinct fuel trends are then estimated by comparing fuel and concentration trends and further substantiated by inādepth examination of emission measurements. We recommend (1) increasing emission factors for preregulation vehicles by 80ā250%; (2) increasing emission factors for residential heating stoves and boilers by 70% to 200% for 1980s and before; (3) explicitly representing naturally aspired offāroad engines for 1980s and before; and (4) explicitly representing certified wood stoves after 1985. We also evaluate other possible sources for discrepancy between model and measurement, including bias in modeled meteorology, subgrid spatial heterogeneity of concentrations, and inconsistencies in reported fuel consumption. The updated U.S. emissions are higher than the a priori estimate by 80% between 1960 and 1980, totaling 690 Gg/year in 1960 and 620 Gg/year in 1970 (excluding open burning). The revised inventory shows a strongly decreasing trend that was present in the observations but missing in the a priori inventory.Key PointsSystematic evaluation of longāterm U.S. black carbon observations identifies a small number of poorly estimated emission sourcesUpdated black carbon emission is higher than the previous estimate by 80% for 1960ā1980, showing a decreasing trend as found in observationEmission factors for preregulation vehicles, offāroad engines, and residential heating stoves in 1980 and before should be increasedPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149266/1/jgrd55339_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149266/2/jgrd55339.pd
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