417 research outputs found
Opposing and following responses in sensorimotor speech control : why responses go both ways
When talking, speakers continuously monitor and use the auditory feedback of their own voice to control and inform speech production processes. When speakers are provided with auditory feedback that is perturbed in real time, most of them compensate for this by opposing the feedback perturbation. But some speakers follow the perturbation. In the current study, we investigated whether the state of the speech production system at perturbation onset may determine what type of response (opposing or following) is given. The results suggest that whether a perturbation-related response is opposing or following depends on ongoing fluctuations of the production system: It initially responds by doing the opposite of what it was doing. This effect and the non-trivial proportion of following responses suggest that current production models are inadequate: They need to account for why responses to unexpected sensory feedback depend on the production-system’s state at the time of perturbation
A contracting circumbinary molecular ring with an inner cavity of about 140 AU around Ori 139-409
Sensitive and subarcsecond resolution ( 0.7\arcsec) CHOH(7
6) line and 890 m continuum observations made with the
Submillimeter Array (SMA) towards the hot molecular circumbinary ring
associated with the young multiple star Ori 139-409 are presented. The
CHOH(7 - 6) emission from the ring is well resolved at
this angular resolution revealing an inner cavity with a size of about 140 AU.
A LTE model of a Keplerian disk with an inner cavity of the same size confirms
the presence of this cavity. Additionally, this model suggests that the
circumbinary ring is contracting with a velocity of V 1.5 km
s toward the binary central compact circumstellar disks reported at a
wavelength of 7 mm. {\bf The inner central cavity seems to be formed by the
tidal effects of the young stars in the middle of the ring.} The ring appears
to be not a stationary object. Furthermore, the infall velocity we determine is
about a factor of 3 slower than the free-fall velocity corresponding to the
dynamical mass. This would correspond to a mass accretion rate of about
10 M/yr. We found that the dust emission associated with Ori
139-409 appears to be arising from the circumstellar disks with no strong
contribution from the molecular gas ring. A simple comparison with other
classical molecular dusty rings (e.g. GG Tau, UZ Tau, and UY Aur) suggests that
Ori 139-409 could be one of the youngest circumbinary rings reported up to
date. Finally, our results confirm that the circumbinary rings are actively
funneling fresh gas material to the central compact binary circumstellar disks,
i.e. to the protostars in the very early phases of their evolution.Comment: Accepted by MNRA
Consistency influences altered auditory feedback processing
Previous research on the effect of perturbed auditory feedback in speech production has focused on two types of responses. In the short term, speakers generate compensatory motor commands in response to unexpected perturbations. In the longer term, speakers adapt feedforward motor programs in response to feedback perturbations, in order to avoid future errors. The current study investigated the relation between these two types of responses to altered auditory feedback. Specifically, it was hypothesized that consistency in previous feedback perturbations would influence whether speakers adapt their feedforward motor programs. In an altered auditory feedback paradigm, formant perturbations were applied either across all trials (the consistent condition) or only to some trials while the others remained unperturbed (the inconsistent condition). The results showed that speakers’ responses were affected by feedback consistency, with stronger speech changes in the consistent condition compared to the inconsistent condition. Current models of speech-motor control can explain this consistency effect. However, the data also suggest compensation and adaptation are distinct processes, which is not in line with all current models
A Comparative Study on the Roll-to-Roll Processing of a Silicate–Polyvinyl Alcohol Composite Barrier Lacquer Using Slot-Die and Reverse Gravure Coating Techniques
The integration of platelet-shaped montmorillonite particles to improve the oxygen barrier
of polyvinyl-alcohol-based barrier layers is state-of-the-art, but research on roll-to-roll coatings of
such composite barrier lacquers has not been widely published. In this study, two different coating
techniques, slot-die and reverse gravure, were used on a roll-to-roll scale to apply barrier lacquers
comprising polyvinyl alcohol and montmorillonite. The lacquers were analyzed regarding viscosity at
certain shear rates and surface energy and the dried coating layers regarding oxygen barrier, surface
morphology, and particle orientation. Low permeability coefficients delivering a high oxygen barrier
of 0.14 and 0.12 cm3 (STP) 1μm.m2 d bar were achieved for the coating layers with slot-die and reverse gravure
coating, respectively. It turned out that the properties of the barrier lacquer need to be adjusted to
the coating technique to achieve high oxygen barrier performance. By tailoring the barrier lacquer
formulation, the orientation of the platelet-shaped montmorillonite particles can be achieved using
both techniques. A low solid content of down to 3 wt% is preferable for the premetered slot-die
coating, because it results in low agglomeration quantity in the coating layer. A high solid content of
up to 9 wt% is preferable for the self-metered reverse gravure coating to assure a homogeneously
coated layer
Astrometry with the Keck-Interferometer: the ASTRA project and its science
The sensitivity and astrometry upgrade ASTRA of the Keck Interferometer is
introduced. After a brief overview of the underlying interferometric
principles, the technology and concepts of the upgrade are presented. The
interferometric dual-field technology of ASTRA will provide the KI with the
means to observe two objects simultaneously, and measure the distance between
them with a precision eventually better than 100 uas. This astrometric
functionality of ASTRA will add a unique observing tool to fields of
astrophysical research as diverse as exo-planetary kinematics, binary
astrometry, and the investigation of stars accelerated by the massive black
hole in the center of the Milky Way as discussed in this contribution.Comment: 22 pages, 10 figures (low resolution), contribution to the
summerschool "Astrometry and Imaging with the Very Large Telescope
Interferometer", 2 - 13 June, 2008, Keszthely, Hungary, corrected authorlis
Reporting randomised trials of social and psychological interventions: the CONSORT-SPI 2018 Extension
Background:
Randomised controlled trials (RCTs) are used to evaluate social and psychological interventions and inform policy decisions about them. Accurate, complete, and transparent reports of social and psychological intervention RCTs are essential for understanding their design, conduct, results, and the implications of the findings. However, the reporting of RCTs of social and psychological interventions remains suboptimal. The CONSORT Statement has improved the reporting of RCTs in biomedicine. A similar high-quality guideline is needed for the behavioural and social sciences. Our objective was to develop an official extension of the Consolidated Standards of Reporting Trials 2010 Statement (CONSORT 2010) for reporting RCTs of social and psychological interventions: CONSORT-SPI 2018.
Methods:
We followed best practices in developing the reporting guideline extension. First, we conducted a systematic review of existing reporting guidelines. We then conducted an online Delphi process including 384 international participants. In March 2014, we held a 3-day consensus meeting of 31 experts to determine the content of a checklist specifically targeting social and psychological intervention RCTs. Experts discussed previous research and methodological issues of particular relevance to social and psychological intervention RCTs. They then voted on proposed modifications or extensions of items from CONSORT 2010.
Results:
The CONSORT-SPI 2018 checklist extends 9 of the 25 items from CONSORT 2010: background and objectives, trial design, participants, interventions, statistical methods, participant flow, baseline data, outcomes and estimation, and funding. In addition, participants added a new item related to stakeholder involvement, and they modified aspects of the flow diagram related to participant recruitment and retention.
Conclusions:
Authors should use CONSORT-SPI 2018 to improve reporting of their social and psychological intervention RCTs. Journals should revise editorial policies and procedures to require use of reporting guidelines by authors and peer reviewers to produce manuscripts that allow readers to appraise study quality, evaluate the applicability of findings to their contexts, and replicate effective interventions
Uniformity in the Wiener-Wintner theorem for nilsequences
We prove a uniform extension of the Wiener-Wintner theorem for nilsequences
due to Host and Kra and a nilsequence extension of the topological
Wiener-Wintner theorem due to Assani. Our argument is based on (vertical)
Fourier analysis and a Sobolev embedding theorem.Comment: v3: 18 p., proof that the cube construction produces compact
homogeneous spaces added, measurability issues in the proof of Theorem 1.5
addressed. We thank the anonymous referees for pointing out these gaps in v
Imaging protoplanets: observing transition disks with non-redundant masking
Transition disks, protoplanetary disks with inner clearings, are promising
objects in which to directly image forming planets. The high contrast imaging
technique of non-redundant masking is well posed to detect planetary mass
companions at several to tens of AU in nearby transition disks. We present
non-redundant masking observations of the T Cha and LkCa 15 transition disks,
both of which host posited sub-stellar mass companions. However, due to a loss
of information intrinsic to the technique, observations of extended sources
(e.g. scattered light from disks) can be misinterpreted as moving companions.
We discuss tests to distinguish between these two scenarios, with applications
to the T Cha and LkCa 15 observations. We argue that a static,
forward-scattering disk can explain the T Cha data, while LkCa 15 is best
explained by multiple orbiting companions.Comment: SPIE conference proceedin
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