1,288 research outputs found
Sensitivity Analysis of List Scheduling Heuristics
When jobs have to be processed on a set of identical parallel machines so as to minimize the makespan of the schedule, list scheduling rules form a popular class of heuristics. The order in which jobs appear on the list is assumed here to be determined by the relative size of their processing times; well known special cases are the LPT rule and the SPT rule, in which the jobs are ordered according to non-increasing and non-decreasing processing time respectively. When one of the job processing times is gradually increased, the schedule produced by a list scheduling rule will be affected in a manner reflecting its sensitivity to data perturbations. We analyze this phenomenon and obtain analytical support for the intuitively plausible notion that the sensitivity of a list scheduling rule increases with the quality of the schedule produced
Tackle your Tics:pilot findings of a brief, intensive group-based exposure therapy program for children with tic disorders
Tourette syndrome (TS) and other chronic tic disorders (CTD) are prevalent neurodevelopmental disorders, which can have a huge burden on families and society. Behavioral treatment is a first-line intervention for tic disorders. Despite demonstrated efficacy, tic reduction and utilization rates of behavioral treatment remain relatively low. Patient associations point to an urgent need for easy-to-undergo treatments that focus both on tic reduction and improvement of quality of life. To enhance treatment outcome and overcome treatment barriers, this pilot study's aim was to investigate the feasibility and preliminary results of a brief, intensive group-based treatment. Tackle your Tics is a 4-day intensive and comprehensive group-based program for children and adolescents (9-17 years) with a tic disorder, consisting of exposure and response prevention (ERP) treatment and additional supporting components, such as coping strategies, relaxing activities and parent support. Assessments were performed pre- and post-treatment and at 2 months follow-up, to test outcomes on tic severity and quality of life, and explore premonitory urges, emotional and behavioral functioning and treatment satisfaction (N = 14, of whom 13 completed the treatment). Parents and children rated this treatment positive on a treatment satisfaction questionnaire. On tic severity (Yale Global Tic Severity Scale) and quality of life (Gilles de la Tourette Syndrome Quality of Life Scale for children and adolescents), improvements between pre-treatment and follow-up were found. Intensive ERP in group format is promising as a feasible treatment to improve both tic severity as well as quality of life. Larger controlled trials are needed to establish its effectiveness
Optics-less smart sensors and a possible mechanism of cutaneous vision in nature
Optics-less cutaneous (skin) vision is not rare among living organisms,
though its mechanisms and capabilities have not been thoroughly investigated.
This paper demonstrates, using methods from statistical parameter estimation
theory and numerical simulations, that an array of bare sensors with a natural
cosine-law angular sensitivity arranged on a flat or curved surface has the
ability to perform imaging tasks without any optics at all. The working
principle of this type of optics-less sensor and the model developed here for
determining sensor performance may be used to shed light upon possible
mechanisms and capabilities of cutaneous vision in nature
Feasibility of diffusion tensor imaging (DTI) with fibre tractography of the normal female pelvic floor
To prospectively determine the feasibility of diffusion tensor imaging (DTI) with fibre tractography as a tool for the three-dimensional (3D) visualisation of normal pelvic floor anatomy. Five young female nulliparous subjects (mean age 28 ± 3 years) underwent DTI at 3.0T. Two-dimensional diffusion-weighted axial spin-echo echo-planar (SP-EPI) pulse sequence of the pelvic floor was performed, with additional T2-TSE multiplanar sequences for anatomical reference. Fibre tractography for visualisation of predefined pelvic floor and pelvic wall muscles was performed offline by two observers, applying a consensus method. Three eigenvalues (λ1, λ2, λ3), fractional anisotropy (FA) and mean diffusivity (MD) were calculated from the fibre trajectories. In all subjects fibre tractography resulted in a satisfactory anatomical representation of the pubovisceral muscle, perineal body, anal - and urethral sphincter complex and internal obturator muscle. Mean FA values ranged from 0.23 ± 0.02 to 0.30 ± 0.04, MD values from 1.30 ± 0.08 to 1.73 ± 0.12 × 10(-)³ mm²/s. Muscular structures in the superficial layer of the pelvic floor could not be satisfactorily identified. This study demonstrates the feasibility of visualising the complex three-dimensional pelvic floor architecture using 3T-DTI with fibre tractography. DTI of the deep female pelvic floor may provide new insights into pelvic floor disorder
Clinically relevant potential drug-drug interactions in intensive care patients:A large retrospective observational multicenter study
Purpose: Potential drug-drug interactions (pDDIs) may harm patients admitted to the Intensive Care Unit (ICU). Due to the patient's critical condition and continuous monitoring on the ICU, not all pDDIs are clinically relevant. Clinical decision support systems (CDSSs) warning for irrelevant pDDIs could result in alert fatigue and overlooking important signals. Therefore, our aim was to describe the frequency of clinically relevant pDDIs (crpDDIs) to enable tailoring of CDSSs to the ICU setting. Materials & methods: In this multicenter retrospective observational study, we used medication administration data to identify pDDIs in ICU admissions from 13 ICUs. Clinical relevance was based on a Delphi study in which intensivists and hospital pharmacists assessed the clinical relevance of pDDIs for the ICU setting. Results: The mean number of pDDIs per 1000 medication administrations was 70.1, dropping to 31.0 when considering only crpDDIs. Of 103,871 ICU patients, 38% was exposed to a crpDDI. The most frequently occurring crpDDIs involve QT-prolonging agents, digoxin, or NSAIDs. Conclusions: Considering clinical relevance of pDDIs in the ICU setting is important, as only half of the detected pDDIs were crpDDIs. Therefore, tailoring CDSSs to the ICU may reduce alert fatigue and improve medication safety in ICU patients
The asymptotic behaviour of a distributive sorting method
In the distributive sorting method of Dobosiewicz, both the interval between the minimum and the median of the numbers to be sorted and the interval between the median and the maximum are partitioned inton/2 subintervals of equal length; the procedure is then applied recursively on each subinterval containing more than three numbers. We refine and extend previous analyses of this method, e.g., by establishing its asymptotic linear behaviour under various probabilistic assumptions
Kinetic theory of hydrodynamic flows. I. The generalized normal solution method and its application to the drag on a sphere
Photo- and Electro-Disintegration of 3He at Threshold and pd Radiative Capture
The present work reports results for: pd radiative capture observables
measured at center-of-mass (c.m.) energies in the range 0--100 keV and at 2 MeV
by the TUNL and Wisconsin groups, respectively; contributions to the
Gerasimov-Drell-Hearn (GDH) integral in 3He from the two- up to the three-body
breakup thresholds, compared to experimental determinations by the TUNL group
in this threshold region; longitudinal, transverse, and interference response
functions measured in inclusive polarized electron scattering off polarized 3He
at excitation energies below the threshold for breakup into ppn, compared to
unpolarized longitudinal and transverse data from the Saskatoon group. The
calculations are based on a realistic Hamiltonian with two- and three-nucleon
interactions and a realistic current operator, including one- and two-body
components. The theoretical predictions obtained by including only one-body
currents are in violent disagreement with data. These differences between
theory and experiment are, to a large extent, removed when two-body currents
are taken into account, although some rather large discrepancies remain in the
c.m. energy range 0--100 keV, particularly for the pd differential cross
section and tensor analyzing power at small angles, and contributions to the
GDH integral. A rather detailed analysis indicates that these discrepancies
have, in large part, a common origin, and can be traced back to an excess
strength obtained in the theoretical calculation of the E1 reduced matrix
element associated with the pd channel having L,S,J=1,1/2,3/2. It is suggested
that this lack of E1 strength observed experimentally might have implications
for the nuclear interaction at very low energies. Finally, the validity of the
long-wavelength approximation for electric dipole transitions is discussed.Comment: 47 pages RevTex file, 10 PostScript figures, submitted to Phys. Rev.
Threshold Electrodisintegration of ^3He
Cross sections were measured for the near-threshold electrodisintegration of
^3He at momentum transfer values of q=2.4, 4.4, and 4.7 fm^{-1}. From these and
prior measurements the transverse and longitudinal response functions R_T and
R_L were deduced. Comparisons are made against previously published and new
non-relativistic A=3 calculations using the best available NN potentials. In
general, for q<2 fm^{-1} these calculations accurately predict the threshold
electrodisintegration of ^3He. Agreement at increasing q demands consideration
of two-body terms, but discrepancies still appear at the highest momentum
transfers probed, perhaps due to the neglect of relativistic dynamics, or to
the underestimation of high-momentum wave-function components.Comment: 9 pages, 7 figures, 1 table, REVTEX4, submitted to Physical Review
Kondo effect in Ce(x)La(1-x)Cu(2.05)Si(2) intermetallics
The magnetic susceptibility and susceptibility anisotropy of the quasi-binary
alloy system Ce(x)La(1-x)Cu(2.05)Si(2) have been studied for low concentration
of Ce ions. The single-ion desc ription is found to be valid for x < 0.1. The
experimental results are discussed in terms of t he degenerate
Coqblin-Schrieffer model with a crystalline electric field splitting Delta =
330 K. The properties of the model, obtained by combining the lowest-order
scaling and the pertur bation theory, provide a satisfactory description of the
experimental data down to 30 K. The e xperimental results between 20 K and 2 K
are explained by the exact solution of the Kondo mode l for an effective
doublet.Comment: 11 pages, 13 Postscript figures, 1 tabl
- …