1,050 research outputs found
Exploring probabilistic grammars of symbolic music using PRISM
In this paper we describe how we used the logic-based probabilistic
programming language PRISM to conduct a systematic comparison
of several probabilistic models of symbolic music, including 0th and
1st order Markov models over pitches and intervals, and a probabilistic
grammar with two parameterisations. Using PRISM allows us to take
advantage of variational Bayesian methods for assessing the goodness of
fit of the models. When applied to a corpus of Bach chorales and the Essen
folk song collection, we found that, depending on various parameters, the
probabilistic grammars sometimes but not always out-perform the simple
Markov models. Examining how the models perform on smaller subsets
of pieces, we find that the simpler Markov models do out-perform the
best grammar-based model at the small end of the scale
Comparing models of symbolic music using probabilistic grammars and probabilistic programming
We conduct a systematic comparison of several probabilistic
models of symbolic music, including zeroth and first order
Markov models over pitches and intervals, a hidden Markov
model over pitches, and a probabilistic context free grammar
with two parameterisations, all implemented uniformly
using a probabilistic programming language (PRISM). This
allows us to take advantage of variational Bayesian methods
for learning parameters and assessing the goodness of fit of
the models in a principled way. When applied to a corpus
of Bach chorales and the Essen folk song collection, we
show that, depending on various parameters, the probabilistic
grammars sometimes but not always out-perform the
simple Markov models. On looking for evidence of over-
fitting of complex models to small datasets, we find that
even the smallest dataset is sufficient to support the richest
parameterisation of the probabilistic grammars. However,
examining how the models perform on smaller subsets of
pieces, we find that the simpler Markov models do indeed
out-perform the best grammar-based model at the small end
of the scale
Compression-based Dependencies Among Rhythmic Motifs in a Score
Music similarity has been widely studied through melodic and harmonic matching, clustering, and using various metrics for measuring distance. Such analyses offer the musicologist a view of the ‘sameness’ of parts of a score. However, similarity alone does not necessarily allow exploitation of that sameness in reasoning about the music. In this paper, we present work in progress to investigate rhythm similarity at various scales, beginning at the smallest (single measures or groups of measures). We use normalised compression distance and variations thereof to derive similarity-based dependencies between parts of the music. Establishing such dependencies may allow software engineering dependence analysis techniques to be applied to music to, e.g. remove from focus aspects not relevant to a particular enquiry (‘slicing’), determine the sensitivity of later parts of the music on former parts (‘impact analysis’), and to find motivic processes and developments within the musical form. The analysis will thus draw on software engineering techniques, information theory, and data compression. Our results thus far show that text-based compressors introduce significant non-linear artefacts at small scales making similarity identification based on compressed lengths difficult. Future work will involve progressively larger scale music to determine the sensitivity of the results to the size of music being analysed in order to guide musicologists wanting to adopt similar approaches. We expect to find that at larger scales, the artefacts in text compression become less significant and identifying the threshold at which this happens is thus important. We discuss tree compression as having the potential to capture musically-important relationships lost by text compression and believe that this approach would be more successful at small scales
Health Workers' Performance in the Implementation of Patient Centred Tuberculosis Treatment (PCT) Strategy Under Programmatic Conditions in Tanzania: A Cross Sectional Study.
Patient Centred Tuberculosis Treatment (PCT) is a promising treatment delivery strategy for Mycobacterium tuberculosis (TB). It aims to improve adherence to treatment by giving patients the choice of having drug intake supervised at the health facility by a medical professional or at home by a supporter of their choice. A cross-sectional survey was undertaken in three districts of Tanzania during October 2007, one year after PCT was rolled out nationally. Semi-structured questionnaires were used to assess whether key elements of the PCT approach were being implemented, to evaluate supporters' knowledge, to capture opinions on factors contributing to treatment completion, and to assess how treatment completion was measured. Transcripts from open-ended responses were analysed using framework analysis. Interviews were conducted with 127 TB patients, 107 treatment supporters and 70 health workers. In total, 25.2% of TB patients were not given a choice about the place of treatment by health workers, and only 13.7% of those given a choice reported that they were given adequate time to make their decision. Only 24.3% of treatment supporters confirmed that they were instructed how to complete patients' treatment cards. Proper health education was the factor most frequently reported by health workers as favouring successful completion of TB treatment (45.7%). The majority of health workers (68.6%) said they checked returned blister packs to verify whether patients had taken their treatment, but only 20.0% checked patients' treatment cards. The provision of choice of treatment location, information on treatment, and guidance for treatment supporters need to be improved. There is a requirement for regular re-training of health workers with effective supportive supervision if successful implementation of the PCT approach is to be sustained
Measurement of the t(t)over-bar production cross-section as a function of jet multiplicity and jet transverse momentum in 7 TeV proton-proton collisions with the ATLAS detector
The tt production cross-section dependence on jet multiplicity and jet transverse momentum is reported for proton–proton collisions at a centre-of-mass energy of 7 TeV in the single-lepton channel. The data were collected with the ATLAS detector at the CERN Large Hadron Collider and comprise the full 2011 data sample corresponding to an integrated luminosity of 4.6 fb−1 . Differential crosssections are presented as a function of the jet multiplicity for up to eight jets using jet transverse momentum thresholds of 25, 40, 60, and 80 GeV, and as a function of jet transverse momentum up to the fifth jet. The results are shown after background subtraction and corrections for all detector effects, within a kinematic range closely matched to the experimental acceptance. Several QCD-based Monte Carlo models are compared with the results. Sensitivity to the parton shower modelling is found at the higher jet multiplicities, at high transverse momentum of the leading jet and in the transverse momentum spectrum of the fifth leading jet. The MC@NLO+HERWIG MC is found to predict too few events at higher jet multiplicities
Determinants of muslims teachers' practice on infusing islamic manners(Adab) in the classroom in the three southern boarder provinces
The objectives of this research are to develop, examine and validate a model of
infusing Islamic manners (adab) in the classroom (iMIS). A proposed model consists of
endogenous variables (teacher attributes and perceived support) and exogenous variables
(teachers‟ performance in iMIS). A survey instrument was administratered to 371 Malay-Muslim teachers at public primary schools in Narathiwat, Yala and Pattani Provinces,Thailand. The structural equation modeling (SEM) is used to validate and test the model fit to the empirical data. The results show that the only three proposed teacher attributes (self-efficacy, values and organizational commitment) and two factors of teachers‟ perceived support (peer and curriculum support) directly influence to their performance in iMIS. Discussion centers the practical implications of these results
Adherence to Tuberculosis Therapy among Patients Receiving Home-Based Directly Observed Treatment: Evidence from the United Republic of Tanzania.
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Non-adherence to tuberculosis (TB) treatment is the leading contributor to the selection of drug-resistant strains of Mycobacterium tuberculosis and subsequent treatment failure. Tanzania introduced a TB Patient Centred Treatment (PCT) approach which gives new TB patients the choice between home-based treatment supervised by a treatment supporter of their own choice, and health facility-based treatment observed by a medical professional. The aim of this study was to assess the extent and determinants of adherence to anti-TB therapy in patients opting for home-based treatment under the novel PCT approach. In this cross-sectional study, the primary outcome was the percentage of patients adherent to TB therapy as detected by the presence of isoniazid in urine (IsoScreen assay). The primary analysis followed a non-inferiority approach in which adherence could not be lower than 75%. Logistic regression was used to examine the influence of potentially predictive factors. A total of 651 new TB patients were included. Of these, 645 (99.1%) provided urine for testing and 617 patients (95.7%; 90%CI 94.3-96.9) showed a positive result. This result was statistically non-inferior to the postulated adherence level of 75% (p<0.001). Adherence to TB therapy under home-based Directly Observed Treatment can be ensured in programmatic settings. A reliable supply of medication and the careful selection of treatment supporters, who preferably live very close to the patient, are crucial success factors. Finally, we recommend a cohort study to assess the rate of adherence throughout the full course of TB treatment
Effect of cyclic heat treatment process on the pitting corrosion resistance of EN-1.4405 martensitic, EN-1.4404 austenitic, and EN-1.4539 austenitic stainless steels in chloride-sulfate solution.
The effect of high temperature variation on the corrosion resistance of
EN-1.4405, EN-1.4404, and EN-1.4539 stainless steels in 2 M H2SO4/3.5% NaCl
solution was studied. Untreated EN 1.4405 exhibited the highest corrosion
rate at 4.775 mm/year compared to untreated EN 1.4539 with the lowest corrosion
rate (1.043 mm/year). Repetitive heat treatment significantly decreased
the corrosion rate of the steels by 54.61%, 27.83%, and 50.28% to 2.167, 1.396,
and 0.519 mm/year. EN-1.4539 steel exhibited the shortest metastable pitting
activity among the untreated steels due to higher resistance to transient pit
formation while heat treated EN-1.4404 and EN-1.4539 steels exhibited double
metastable pitting activity. Heat treated EN-1.4405 was unable to passivate
after anodic polarization signifying weak corrosion resistance. Pitting current of
heat-treated steels was generally higher than the untreated counterparts. Heat
treatment extended the passivation range value of EN-1.4405 and EN-1.4539
steels compared to those of the untreated steels. The corrosion potential of
heat-treated steels significantly shifted to electronegative values. The optical
image of untreated and heat treated EN-1.4404 and EN-1.4539 steels were
generally similar while the images for EN-1.4405 significantly contrast each
other
Second order QCD corrections to inclusive semileptonic b \to Xc l \bar \nu_l decays with massless and massive lepton
We extend previous computations of the second order QCD corrections to
semileptonic b \to c inclusive transitions, to the case where the charged
lepton in the final state is massive. This allows accurate description of b \to
c \tau \bar \nu_\tau decays. We review techniques used in the computation of
O(\alpha_s^2) corrections to inclusive semileptonic b \to c transitions and
present extensive numerical studies of O(\alpha_s^2) QCD corrections to b \to c
l \bar \nu_l decays, for l =e, \tau.Comment: 30 pages, 4 figures, 5 table
Role of oesophageal cooling in the prevention of oesophageal injury in atrial fibrillation catheter ablation: a systematic review and meta-analysis of randomized controlled trials.
AIMS: To evaluate the efficacy of oesophageal cooling in the prevention of oesophageal injury in patients undergoing atrial fibrillation (AF) catheter ablation. METHODS AND RESULTS: Comprehensive search of MEDLINE, EMBASE, and Cochrane databases through April 2022 for randomized controlled trials (RCTs) evaluating the role of oesophageal cooling compared with control in the prevention of oesophageal injury during AF catheter ablation. The study primary outcome was the incidence of any oesophageal injury. The meta-analysis included 4 RCTs with a total of 294 patients. There was no difference in the incidence of any oesophageal injury between oesophageal cooling and control [15% vs. 19%; relative risk (RR) 0.86; 95% confidence interval (CI) 0.31-2.41]. Compared with control, oesophageal cooling showed lower risk of severe oesophageal injury (1.5% vs. 9%; RR 0.21; 95% CI 0.05-0.80). There were no significant differences among the two groups in mild to moderate oesophageal injury (13.6% vs. 12.1%; RR 1.09; 95% CI 0.28-4.23), procedure duration [standardized mean difference (SMD) -0.03; 95% CI -0.36-0.30], posterior wall radiofrequency (RF) time (SMD 0.27; 95% CI -0.04-0.58), total RF time (SMD -0.50; 95% CI -1.15-0.16), acute reconnection incidence (RR 0.93; 95% CI 0.02-36.34), and ablation index (SMD 0.16; 95% CI -0.33-0.66). CONCLUSION: Among patients undergoing AF catheter ablation, oesophageal cooling did not reduce the overall risk of any oesophageal injury compared with control. Oesophageal cooling might shift the severity of oesophageal injuries to less severe injuries. Further studies should evaluate the long-term effects after oesophageal cooling during AF catheter ablation
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