348 research outputs found
Cognitive Rhythms Reluctantly Revisited
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.In response to the Power (1983) - Beattie (1984) controversy, a more general critique of the construct of cognitive rhythms is presented. It is argued that the term itself is a misnomer, that the relevance of articulation rate has been neglected, that fluent and hesitant phases of cognitive rhythms have been assessed both subjectively and intuitively, that the speech-production model underlying the concept is simplistic, and that the empirical evidence is based on an extraordinarily small corpus which has been described inadequately in the research literature
Analysis of permanent magnets as elasmobranch bycatch reduction devices in hook-and-line and longline trials
Previous studies indicate that elasmobranch fishes (sharks,
skates and rays) detect the Earth’s geomagnetic field by indirect magnetoreception through electromagnetic
induction, using their ampullae of Lorenzini. Applying this concept, we evaluated the capture of elasmobranchs in the presence of permanent magnets in hook-and-line and inshore
longline fishing experiments. Hooks with neodymium-iron-boron magnets significantly reduced the capture of
elasmobranchs overall in comparison with control and procedural control hooks in the hook-and-line experiment.
Catches of Atlantic sharpnose shark (Rhizoprionodon terraenovae) and smooth dogfish (Mustelus canis) were signif icantly reduced with magnetic hook-and-line treatments, whereas catches of spiny dogfish (Squalus acanthias) and clearnose skate (Raja eglanteria) were not.
Longline hooks with barium-ferrite magnets significantly reduced total elasmobranch capture when compared with control hooks. In the longline study, capture of blacktip sharks (Carcharhinus limbatus) and southern stingrays (Dasyatis americana) was reduced on magnetic hooks, whereas
capture of sandbar shark (Carcharhinus plumbeus) was not affected. Teleosts, such as red drum (Sciaenops ocellatus), Atlantic croaker (Micropogonias undulatus), oyster toadfish
(Opsanus tau), black sea bass (Centropristis striata), and the bluefish (Pomatomas saltatrix), showed no hook preference in either hook-and-line or longline studies. These results indicate that permanent magnets, although eliciting species-specific capture trends, warrant further investigation in commercial longline and recreational fisheries, where bycatch mortality is a leading contributor to declines in elasmobranch populations
The Use of Time in Storytelling
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.A total of 18 experimental corpora of spontaneous speech in five languages (English, Finnish, French, German, and Spanish) were examined under the hypothesis that they are characterized by commonalities in the use of time. Each study was based on the same speech type, story telling elicited by pictorial materials. The temporal measures were speech and articulation rates, pause duration, phrase length, and percentage of pause time/total time. The hypothesis was confirmed except for studies carried out with identifiably variant methodologies. Further support for the hypothesis was found by contrasting the use of time characteristic of interviewees' speech
The Trouble with "Articulatory" Pauses
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.The historical provenance of a minimum cut-off point (of about 0.25 sec) for pauses in temporal analyses of speech production is associated with Goldman-Eisler's usage. Her rationale was the predominance of articulatory pauses at lengths shorter than 0.25 sec. Both phonotactic facts and empirical analysis of several corpora of readings disconfirm this predominance with respect to pauses 0.13-0.25 sec in length. The vast majority of these pauses are found to be psychological; they are determined by syntax, punctuation, rhetorical and expressive emphasis, poetic format, and stylistic pecularities
Oncogenic D816V-KIT signaling in mast cells causes persistent IL-6 production
Persistent dysregulation of IL-6 production and signaling have been implicated in the pathology of various cancers. In systemic mastocytosis, increased serum levels of IL-6 associate with disease severity and progression, although the mechanisms involved are not well understood. Since systemic mastocytosis often associates with the presence in hematopoietic cells of a somatic gain-of-function variant in KIT, D816V-KIT, we examined its potential role in IL-6 upregulation. Bone marrow mononuclear cultures from patients with greater D816V allelic burden released increased amounts of IL-6 which correlated with the percentage of mast cells in the cultures. Intracellular IL-6 staining by flow cytometry and immunofluorescence was primarily associated with mast cells and suggested a higher percentage of IL-6 positive mast cells in patients with higher D816V allelic burden. Furthermore, mast cell lines expressing D816V-KIT, but not those expressing normal KIT or other KIT variants, produced constitutively high IL-6 amounts at the message and protein levels. We further demonstrate that aberrant KIT activity and signaling are critical for the induction of IL-6 and involve STAT5 and PI3K pathways but not STAT3 or STAT4. Activation of STAT5A and STATB downstream of D816V-KIT was mediated by JAK2 but also by MEK/ERK1/2, which not only promoted STAT5 phosphorylation but also its long-term transcription. Our study thus supports a role for mast cells and D816V-KIT activity in IL-6 dysregulation in mastocytosis and provides insights into the intracellular mechanisms. The findings contribute to a better understanding of the physiopathology of mastocytosis and suggest the importance of therapeutic targeting of these pathwaysThis work was supported by the Division of Intramural
Research within the National Institute of Allergy and Infectious
Diseases (NIAID), at the National Institutes of Health.S
Discovery of a Dynamical Cold Point in the Heart of the Sagittarius dSph Galaxy with Observations from the APOGEE Project
The dynamics of the core of the Sagittarius (Sgr) dwarf spheroidal (dSph)
galaxy are explored using high-resolution (R~22,500), H-band, near-infrared
spectra of over 1,000 giant stars in the central 3 deg^2 of the system, of
which 328 are identified as Sgr members. These data, among some of the earliest
observations from the SDSS-III/Apache Point Observatory Galactic Evolution
Experiment (APOGEE) and the largest published sample of high resolution Sgr
dSph spectra to date, reveal a distinct gradient in the velocity dispersion of
Sgr from 11-14 km/s for radii >0.8 degrees from center to a dynamical cold
point of 8 km/s in the Sgr center --- a trend differing from that found in
previous kinematical analyses of Sgr over larger scales that suggest a more or
less flat dispersion profile at these radii. Well-fitting mass models with
either cored and cusped dark matter distributions can be found to match the
kinematical results, although the cored profile succeeds with significantly
more isotropic stellar orbits than required for a cusped profile. It is
unlikely that the cold point reflects an unusual mass distribution. The
dispersion gradient may arise from variations in the mixture of populations
with distinct kinematics within the dSph; this explanation is suggested (e.g.,
by detection of a metallicity gradient across similar radii), but not
confirmed, by the present data. Despite these remaining uncertainties about
their interpretation, these early test data (including some from instrument
commissioning) demonstrate APOGEE's usefulness for precision dynamical studies,
even for fields observed at extreme airmasses.Comment: 15 pages, 3 figure
The Apache Point Observatory Galactic Evolution Experiment: First Detection of High Velocity Milky Way Bar Stars
Commissioning observations with the Apache Point Observatory Galactic
Evolution Experiment (APOGEE), part of the Sloan Digital Sky Survey III, have
produced radial velocities (RVs) for ~4700 K/M-giant stars in the Milky Way
bulge. These high-resolution (R \sim 22,500), high-S/N (>100 per resolution
element), near-infrared (1.51-1.70 um; NIR) spectra provide accurate RVs
(epsilon_v~0.2 km/s) for the sample of stars in 18 Galactic bulge fields
spanning -1-32 deg. This represents the largest
NIR high-resolution spectroscopic sample of giant stars ever assembled in this
region of the Galaxy. A cold (sigma_v~30 km/s), high-velocity peak (V_GSR \sim
+200 km/s) is found to comprise a significant fraction (~10%) of stars in many
of these fields. These high RVs have not been detected in previous MW surveys
and are not expected for a simple, circularly rotating disk. Preliminary
distance estimates rule out an origin from the background Sagittarius tidal
stream or a new stream in the MW disk. Comparison to various Galactic models
suggests that these high RVs are best explained by stars in orbits of the
Galactic bar potential, although some observational features remain
unexplained.Comment: 7 pages, 4 figures, accepted for publication in ApJ Letter
The Open Cluster Chemical Analysis and Mapping Survey: Local Galactic Metallicity Gradient with APOGEE using SDSS DR10
The Open Cluster Chemical Analysis and Mapping (OCCAM) Survey aims to produce
a comprehensive, uniform, infrared-based dataset for hundreds of open clusters,
and constrain key Galactic dynamical and chemical parameters from this sample.
This first contribution from the OCCAM survey presents analysis of 141 members
stars in 28 open clusters with high-resolution metallicities derived from a
large uniform sample collected as part of the SDSS-III/Apache Point Observatory
Galactic Evolution Experiment (APOGEE). This sample includes the first
high-resolution metallicity measurements for 22 open clusters. With this
largest ever uniformly observed sample of open cluster stars we investigate the
Galactic disk gradients of both [M/H] and [alpha/M]. We find basically no
gradient across this range in [alpha/M], but [M/H] does show a gradient for
R_{GC} < 10 kpc and a significant flattening beyond R_{GC} = 10 kpc. In
particular, whereas fitting a single linear trend yields an [M/H] gradient of
-0.09 +/- 0.03$ dex/kpc --- similar to previously measure gradients inside 13
kpc --- by independently fitting inside and outside 10 kpc separately we find a
significantly steeper gradient near the Sun (7.9 <= R_{GC} <= 10) than
previously found (-0.20 +/- 0.08 dex/kpc) and a nearly flat trend beyond 10 kpc
(-0.02 +/- 0.09 dex/kpc).Comment: 6 pages, 4 figures, ApJ letters, in pres
Tracing chemical evolution over the extent of the Milky Way's Disk with APOGEE Red Clump Stars
We employ the first two years of data from the near-infrared, high-resolution
SDSS-III/APOGEE spectroscopic survey to investigate the distribution of
metallicity and alpha-element abundances of stars over a large part of the
Milky Way disk. Using a sample of ~10,000 kinematically-unbiased red-clump
stars with ~5% distance accuracy as tracers, the [alpha/Fe] vs. [Fe/H]
distribution of this sample exhibits a bimodality in [alpha/Fe] at intermediate
metallicities, -0.9<[Fe/H]<-0.2, but at higher metallicities ([Fe/H]=+0.2) the
two sequences smoothly merge. We investigate the effects of the APOGEE
selection function and volume filling fraction and find that these have little
qualitative impact on the alpha-element abundance patterns. The described
abundance pattern is found throughout the range 5<R<11 kpc and 0<|Z|<2 kpc
across the Galaxy. The [alpha/Fe] trend of the high-alpha sequence is
surprisingly constant throughout the Galaxy, with little variation from region
to region (~10%). Using simple galactic chemical evolution models we derive an
average star formation efficiency (SFE) in the high-alpha sequence of ~4.5E-10
1/yr, which is quite close to the nearly-constant value found in
molecular-gas-dominated regions of nearby spirals. This result suggests that
the early evolution of the Milky Way disk was characterized by stars that
shared a similar star formation history and were formed in a well-mixed,
turbulent, and molecular-dominated ISM with a gas consumption timescale (1/SFE)
of ~2 Gyr. Finally, while the two alpha-element sequences in the inner Galaxy
can be explained by a single chemical evolutionary track this cannot hold in
the outer Galaxy, requiring instead a mix of two or more populations with
distinct enrichment histories.Comment: 18 pages, 17 figures. Accepted for publication in Ap
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