417 research outputs found
On the Complexity of Case-Based Planning
We analyze the computational complexity of problems related to case-based
planning: planning when a plan for a similar instance is known, and planning
from a library of plans. We prove that planning from a single case has the same
complexity than generative planning (i.e., planning "from scratch"); using an
extended definition of cases, complexity is reduced if the domain stored in the
case is similar to the one to search plans for. Planning from a library of
cases is shown to have the same complexity. In both cases, the complexity of
planning remains, in the worst case, PSPACE-complete
Enhancement by postfiltering for speech and audio coding in ad-hoc sensor networks
Enhancement algorithms for wireless acoustics sensor networks~(WASNs) are
indispensable with the increasing availability and usage of connected devices
with microphones. Conventional spatial filtering approaches for enhancement in
WASNs approximate quantization noise with an additive Gaussian distribution,
which limits performance due to the non-linear nature of quantization noise at
lower bitrates. In this work, we propose a postfilter for enhancement based on
Bayesian statistics to obtain a multidevice signal estimate, which explicitly
models the quantization noise. Our experiments using PSNR, PESQ and MUSHRA
scores demonstrate that the proposed postfilter can be used to enhance signal
quality in ad-hoc sensor networks
NfL as a biomarker for neurodegeneration and survival in Parkinson disease
OBJECTIVE: To determine if Neurofilament Light chain protein in cerebrospinal fluid (cNfL); a sensitive biomarker of neuroaxonal damage, reflects disease severity or can predict survival in Parkinson's disease (PD). METHODS: We investigated if disease severity, phenotype or survival in patients with new-onset PD correlates with cNfL concentrations around the time of diagnosis in the population-based NYPUM study cohort (n = 99). A second, larger new-onset PD cohort (n = 194) was used for independent validation. Association of brain pathology with the cNfL concentration was examined using striatal dopamine transporter imaging and repeated diffusion tensor imaging, at baseline, 1 and 3 years. RESULTS: Higher cNfL in the early phase of PD was associated with greater severity of all cardinal motor symptoms except tremor, in both cohorts, and with shorter survival and impaired olfaction. cNfL concentrations above the median of 903 ng/L conferred an overall 5.8 times increased hazard of death, during follow-up. After adjustment for age and sex, higher cNfL correlated with striatal dopamine transporter uptake deficits and lower fractional anisotropy in diffusion tensor imaging of several axonal tracts. CONCLUSIONS: cNfL shows usefulness as a biomarker of disease severity and to predict survival in PD. The present results indicate that the cNfL concentration reflects the intensity of the neurodegenerative process, which could be of importance in future clinical trials. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that in patients with PD, cNFL concentrations are associated with more severe disease and shorter survival
The FERRUM project: Transition probabilities for forbidden lines in [FeII] and experimental metastable lifetimes
Accurate transition probabilities for forbidden lines are important
diagnostic parameters for low-density astrophysical plasmas. In this paper we
present experimental atomic data for forbidden [FeII] transitions that are
observed as strong features in astrophysical spectra.
Aims: To measure lifetimes for the 3d^6(^3G)4s a ^4G_{11/2} and 3d^6(^3D)4s b
^4D_{1/2} metastable levels in FeII and experimental transition probabilities
for the forbidden transitions 3d^7 a ^4F_{7/2,9/2}- 3d^6(^3G)4s a ^4G_{11/2}.
Methods: The lifetimes were measured at the ion storage ring facility CRYRING
using a laser probing technique. Astrophysical branching fractions were
obtained from spectra of Eta Carinae, obtained with the Space Telescope Imaging
Spectrograph onboard the Hubble Space Telescope. The lifetimes and branching
fractions were combined to yield absolute transition probabilities.
Results: The lifetimes of the a ^4G_{11/2} and the b ^4D_{1/2} levels have
been measured and have the following values, 0.75(10) s and 0.54(3) s
respectively. Furthermore, we have determined the transition probabilities for
two forbidden transitions of a ^4F_{7/2,9/2}- a ^4G_{11/2} at 4243.97 and
4346.85 A. Both the lifetimes and the transition probabilities are compared to
calculated values in the literature.Comment: 5 pages, accepted for publication in A&
Integrating isotopes and documentary evidence : dietary patterns in a late medieval and early modern mining community, Sweden
We would like to thank the Archaeological Research Laboratory, Stockholm University, Sweden and the Tandem Laboratory (Ă
ngström Laboratory), Uppsala University, Sweden, for undertaking the analyses of stable nitrogen and carbon isotopes in both human and animal collagen samples. Also, thanks to Elin Ahlin Sundman for providing the ÎŽ13C and ÎŽ15N values for animal references from VĂ€sterĂ„s. This research (BĂ€ckströmâs PhD employment at Lund University, Sweden) was supported by the Berit Wallenberg Foundation (BWS 2010.0176) and Jakob and Johan Söderbergâs foundation. The âSala projectâ (excavations and analyses) has been funded by Riksens Clenodium, Jernkontoret, Birgit and Gad Rausingâs Foundation, SAUâs Research Foundation, the Royal Physiographic Society of Lund, Berit Wallenbergs Foundation, Ă
ke Wibergs Foundation, Lars Hiertas Memory, Helge Ax:son Johnsonâs Foundation and The Royal Swedish Academy of Sciences.Peer reviewedPublisher PD
Attachment Styles Within the Coach-Athlete Dyad: Preliminary Investigation and Assessment Development
The present preliminary study aimed to develop and examine the psychometric properties of a new sport-specific self-report instrument designed to assess athletesâ and coachesâ attachment styles. The development and initial validation comprised three main phases. In Phase 1, a pool of items was generated based on pre-existing self-report attachment instruments, modified to reflect a coach and an athleteâs style of attachment. In Phase 2, the content validity of the items was assessed by a panel of experts. A final scale was developed and administered to 405 coaches and 298 athletes (N = 703 participants). In Phase 3, confirmatory factor analysis of the obtained data was conducted to determine the final items of the Coach-Athlete Attachment Scale (CAAS). Confirmatory factor analysis revealed acceptable goodness of fit indexes for a 3-first order factor model as well as a 2-first order factor model for both the athlete and the coach data, respectively. A secure attachment style positively predicted relationship satisfaction, while an insecure attachment style was a negative predictor of relationship satisfaction. The CAAS revealed initial psychometric properties of content, factorial, and predictive validity, as well as reliability
Characteristics of safety information obtained from postmarketing observational studies for re-examination in Japan
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