1. |
- Moberg, Christina, et al.
(författare)
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De unga gör helt rätt när de stämmer staten
- 2022
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Ingår i: Aftonbladet. - 1103-9000.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- 1 620 forskare och lärare i forskarvärlden: Vi ställer oss bakom Auroras klimatkrav
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2. |
- Elowsson, Anders
(författare)
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Modeling Music : Studies of Music Transcription, Music Perception and Music Production
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation presents ten studies focusing on three important subfields of music information retrieval (MIR): music transcription (Part A), music perception (Part B), and music production (Part C).In Part A, systems capable of transcribing rhythm and polyphonic pitch are described. The first two publications present methods for tempo estimation and beat tracking. A method is developed for computing the most salient periodicity (the “cepstroid”), and the computed cepstroid is used to guide the machine learning processing. The polyphonic pitch tracking system uses novel pitch-invariant and tone-shift-invariant processing techniques. Furthermore, the neural flux is introduced – a latent feature for onset and offset detection. The transcription systems use a layered learning technique with separate intermediate networks of varying depth. Important music concepts are used as intermediate targets to create a processing chain with high generalization. State-of-the-art performance is reported for all tasks.Part B is devoted to perceptual features of music, which can be used as intermediate targets or as parameters for exploring fundamental music perception mechanisms. Systems are proposed that can predict the perceived speed and performed dynamics of an audio file with high accuracy, using the average ratings from around 20 listeners as ground truths. In Part C, aspects related to music production are explored. The first paper analyzes long-term average spectrum (LTAS) in popular music. A compact equation is derived to describe the mean LTAS of a large dataset, and the variation is visualized. Further analysis shows that the level of the percussion is an important factor for LTAS. The second paper examines songwriting and composition through the development of an algorithmic composer of popular music. Various factors relevant for writing good compositions are encoded, and a listening test employed that shows the validity of the proposed methods.The dissertation is concluded by Part D - Looking Back and Ahead, which acts as a discussion and provides a road-map for future work. The first paper discusses the deep layered learning (DLL) technique, outlining concepts and pointing out a direction for future MIR implementations. It is suggested that DLL can help generalization by enforcing the validity of intermediate representations, and by letting the inferred representations establish disentangled structures supporting high-level invariant processing. The second paper proposes an architecture for tempo-invariant processing of rhythm with convolutional neural networks. Log-frequency representations of rhythm-related activations are suggested at the main stage of processing. Methods relying on magnitude, relative phase, and raw phase information are described for a wide variety of rhythm processing tasks.
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3. |
- Skibniewski, Mikolaj, et al.
(författare)
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Long-term antithrombotic therapy after coronary artery bypass grafting in patients with preoperative atrial fibrillation. A nationwide observational study from the SWEDEHEART registry
- 2023
-
Ingår i: American Heart Journal. - : Elsevier BV. - 0002-8703 .- 1097-6744. ; 257, s. 69-77
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Tidskriftsartikel (refereegranskat)abstract
- Aims To provide data guiding long-term antithrombotic therapy after coronar y arter y by-pass grafting (CABG) in patients with preoperative atrial fibrillation (AF). Methods and results From the SWEDEHEART registry, we included all patients, between January 2006 and September 2016, with preoperative AF and CHA2DS2-VASC score >2, undergoing CABG. Based on dispensed prescriptions 12 to 18 months after CABG, patients were divided in 3 groups: use of platelet inhibitors (PI) only, oral anticoagulant (OAC) only or a combination of OAC + PI. Outcomes were: Major adverse cardiac and cerebrovascular events (MACCE, [all-cause death, myocardial infarction, or stroke]), net adverse clinical events (NACE, [MACCE or bleeding]) and the individual components of NACE. Inverse probability of treatment weighting was used to adjust for the non-randomized study design. Among 2,564 patients, 1,040 (41%) were treated with PI alone, 1,064 (41%) with OAC alone, and 460 (18%) with PI + OAC. Treatment with PI alone was associated with higher risk for MACCE (adjusted HR 1.43, 95% CI 1.09-1.88), driven by higher risk for stroke and MI, compared with OAC alone. Treatment with PI + OAC, was associated with higher risk for NACE (adjusted HR 1.40, 95% CI 1.06-1.85), driven by higher risk for bleeds, compared with OAC alone. Conclusion In this real-world observational study, a high proportion of patients with AF, undergoing CABG, did not receive a long-term OAC therapy. Treatment with OAC alone was associated with a net clinical benefit, compared with PI alone or PI + OAC. (Am Heart J 2023;257:69-77.)
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4. |
- Akerstrom, Finn, et al.
(författare)
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Association between catheter ablation of atrial fibrillation and mortality or stroke
- 2024
-
Ingår i: Heart. - : BMJ PUBLISHING GROUP. - 1355-6037 .- 1468-201X. ; 110, s. 163-169
-
Tidskriftsartikel (refereegranskat)abstract
- Objective Catheter ablation of atrial fibrillation effectively reduces symptomatic burden. However, its long-term effect on mortality and stroke is unclear. We investigated if patients with atrial fibrillation who undergo catheter ablation have lower risk for all-cause mortality or stroke than patients who are managed medically. Methods We retrospectively included 5628 consecutive patients who underwent first-time catheter ablation for atrial fibrillation between 2008 and 2018 at three major Swedish electrophysiology units. Control individuals with an atrial fibrillation diagnosis but without previous stroke were selected from the Swedish National Patient Register, resulting in a control group of 48 676 patients. Propensity score matching was performed to produce two cohorts of equal size (n=3955) with similar baseline characteristics. The primary endpoint was a composite of all-cause mortality or stroke. Results Patients who underwent catheter ablation were healthier (mean CHA(2)DS(2)-VASc score 1.4 +/- 1.4 vs 1.6 +/- 1.5, p<0.001), had a higher median income (288 vs 212 1000 Swedish krona [KSEK]/year, p<0.001) and had more frequently received university education (45.1% vs 28.9%, p<0.001). Mean follow-up was 4.5 +/- 2.8 years. After propensity score matching, catheter ablation was associated with lower risk for the combined primary endpoint (HR 0.58, 95% CI 0.48 to 0.69). The result was mainly driven by a decrease in all-cause mortality (HR 0.51, 95% CI 0.41 to 0.63), with stroke reduction showing a trend in favour of catheter ablation (HR 0.75, 95% CI 0.53 to 1.07). Conclusions Catheter ablation of atrial fibrillation was associated with a reduction in the primary endpoint of all-cause mortality or stroke. This result was driven by a marked reduction in all-cause mortality.
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5. |
- Andersen, Maria Goul, et al.
(författare)
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Population Pharmacokinetics of Piperacillin in Sepsis Patients : Should Alternative Dosing Strategies Be Considered?
- 2018
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Ingår i: Antimicrobial Agents and Chemotherapy. - : American Society for Microbiology. - 0066-4804 .- 1098-6596. ; 62:5
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Tidskriftsartikel (refereegranskat)abstract
- Sufficient antibiotic dosing in septic patients is essential for reducing mortality. Piperacillin-tazobactam is often used for empirical treatment, but due to the pharmacokinetic (PK) variability seen in septic patients, optimal dosing may be a challenge. We determined the PK profile for piperacillin given at 4 g every 8 h in 22 septic patients admitted to a medical ward. Piperacillin concentrations were compared to the clinical breakpoint MIC for Pseudomonas aeruginosa (16 mg/liter), and the following PK/pharmacodynamic (PD) targets were evaluated: the percentage of the dosing interval that the free drug concentration is maintained above the MIC (fTMIC) of 50% and 100%. A two-compartment population PK model described the data well, with clearance being divided into renal and nonrenal components. The renal component was proportional to the estimated creatinine clearance (eCLCR) and constituted 74% of the total clearance in a typical individual (eCLCR, 83.9 ml/min). Patients with a high eCLCR (>130 ml/min) were at risk of subtherapeutic concentrations for the current regimen, with a 90% probability of target attainment being reached at MICs of 2.0 (50% fTMIC) and 0.125 mg/liter (100% fTMIC). Simulations of alternative dosing regimens and modes of administration showed that dose increment and prolonged infusion increased the chance of achieving predefined PK/PD targets. Alternative dosing strategies may therefore be needed to optimize piperacillin exposure in septic patients. (This study has been registered at ClinicalTrials.gov under identifier NCT02569086.)
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6. |
- Bellec, G., et al.
(författare)
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A social network integrated game experiment to relate tapping to speed perception and explore rhythm reproduction
- 2013
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Ingår i: Proceedings of the Sound and Music Computing Conference 2013. - 9783832534721 ; , s. 19-26
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Konferensbidrag (refereegranskat)abstract
- During recent years, games with a purpose (GWAPs) have become increasingly popular for studying human behaviour [1–4]. However, no standardised method for web-based game experiments has been proposed so far. We present here our approach comprising an extended version of the CaSimIR social game framework [5] for data collection, mini-games for tempo and rhythm tapping, and an initial analysis of the data collected so far. The game presented here is part of the Spot The Odd Song Out game, which is freely available for use on Facebook and on the Web 1 .We present the GWAP method in some detail and a preliminary analysis of data collected. We relate the tapping data to perceptual ratings obtained in previous work. The results suggest that the tapped tempo data collected in a GWAP can be used to predict perceived speed. I toned down the above statement as I understand from the results section that our data are not as good as When averagingthe rhythmic performances of a group of 10 players in the second experiment, the tapping frequency shows a pattern that corresponds to the time signature of the music played. Our experience shows that more effort in design and during runtime is required than in a traditional experiment. Our experiment is still running and available on line.
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7. |
- Bresin, Roberto, et al.
(författare)
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Sound and Music Computing at KTH
- 2012
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Ingår i: Trita-TMH. - Stockholm : KTH Royal Institute of Technology. - 1104-5787. ; 52:1, s. 33-35
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The SMC Sound and Music Computing group at KTH (formerly the Music Acoustics group) is part of the Department of Speech Music and Hearing, School of Computer Science and Communication. In this short report we present the current status of the group mainly focusing on its research.
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8. |
- Bresin, Roberto, et al.
(författare)
-
Sound and Music Computing at KTH
- 2012
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Ingår i: SMC Sweden 2012 Sound and Music Computing, Understanding and Practicing in Sweden. - Stockholm : Department of Speech, Music and Hearing, Royal Institute of Technology. ; , s. 33-35
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Konferensbidrag (refereegranskat)
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9. |
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10. |
- Christersson, Christina, et al.
(författare)
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Comparison of warfarin versus antiplatelet therapy after surgical bioprosthetic aortic valve replacement
- 2020
-
Ingår i: Heart. - : BMJ. - 1355-6037 .- 1468-201X. ; 106:11, s. 838-844
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To compare effectiveness of warfarin and antiplatelet exposure regarding both thrombotic and bleeding events, following surgical aortic valve replacement with a biological prosthesis(bioSAVR).METHODS: The study included all patients in Sweden undergoing a bioSAVR during 2008-2014 who were alive at discharge from the index hospital stay. Exposure was analysed and defined as postdischarge dispension of any antithrombotic pharmaceutical, updated at each following dispensions and categorised as single antiplatelet (SAPT), warfarin, warfarin combined with SAPT, dual antiplatelet (DAPT) or no antithrombotic treatment. Exposure to SAPT was used as comparator. Outcome events were all-cause mortality, ischaemic stroke, haemorrhagic stroke, any thromboembolism and major bleedings. We continuously updated adjustments for comorbidities with any indication for antithrombotic treatment by Cox regression analysis.RESULTS: We identified 9539 patients with bioSAVR (36.8% women) at median age of 73 years with a mean follow-up of 3.13 years. As compared with SAPT, warfarin alone was associated with a lower incidence of ischaemic stroke (HR 0.49, 95% CI 0.35 to 0.70) and any thromboembolism (HR 0.75, 95% CI 0.60 to 0.94) but with no difference in mortality (HR 0.94, 95% CI 0.78 to 1.13). The incidence of haemorrhagic stroke (HR 1.94, 95% CI 1.07 to 3.51) and major bleeding (HR 1.67, 95% CI 1.30 to 2.15) was higher during warfarin exposure. As compared with SAPT, DAPT was not associated with any difference in ischaemic stroke or any thromboembolism. Risk-benefit analyses demonstrated that 2.7 (95% CI 1.0 to 11.9) of the ischaemic stroke cases could potentially be avoided per every haemorrhagic stroke caused by warfarin exposure instead of SAPT during the first year.CONCLUSION: In patients discharged after bioSAVR, warfarin exposure as compared with SAPT exposure was associated with lower long-term risk of ischaemic stroke and thromboembolic events, and with a higher incidence of bleeding events but with similar mortality.
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11. |
- Dubois, Juliette, et al.
(författare)
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Predicting Perceived Dissonance of Piano Chords Using a Chord-Class Invariant CNN and Deep Layered Learning
- 2019
-
Ingår i: Proceedings of 16th Sound & Music Computing Conference (SMC), Malaga, Spain. - 9788409085187 ; , s. 530-536
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Konferensbidrag (refereegranskat)abstract
- This paper presents a convolutional neural network (CNN) able to predict the perceived dissonance of piano chords. Ratings of dissonance for short audio excerpts were com- bined from two different datasets and groups of listeners. The CNN uses two branches in a directed acyclic graph (DAG). The first branch receives input from a pitch esti- mation algorithm, restructured into a pitch chroma. The second branch analyses interactions between close partials, known to affect our perception of dissonance and rough- ness. The analysis is pitch invariant in both branches, fa- cilitated by convolution across log-frequency and octave- wide max-pooling. Ensemble learning was used to im- prove the accuracy of the predictions. The coefficient of determination (R2) between rating and predictions are close to 0.7 in a cross-validation test of the combined dataset. The system significantly outperforms recent computational models. An ablation study tested the impact of the pitch chroma and partial analysis branches separately, conclud- ing that the deep layered learning approach with a pitch chroma was driving the high performance.
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12. |
- Elowsson, Anders, et al.
(författare)
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Algorithmic Composition of Popular Music
- 2012
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Ingår i: Proceedings of the 12th International Conference on Music Perception and Cognition and the 8th Triennial Conference of the European Society for the Cognitive Sciences of Music. ; , s. 276-285
-
Konferensbidrag (refereegranskat)abstract
- Human composers have used formal rules for centuries to compose music, and an algorithmic composer – composing without the aid of human intervention – can be seen as an extension of this technique. An algorithmic composer of popular music (a computer program) has been created with the aim to get a better understanding of how the composition process can be formalized and at the same time to get a better understanding of popular music in general. With the aid of statistical findings a theoretical framework for relevant methods are presented. The concept of Global Joint Accent Structure is introduced, as a way of understanding how melody and rhythm interact to help the listener form expectations about future events. Methods of the program are presented with references to supporting statistical findings. The algorithmic composer creates a rhythmic foundation (drums), a chord progression, a phrase structure and at last the melody. The main focus has been the composition of the melody. The melodic generation is based on ten different musical aspects which are described. The resulting output was evaluated in a formal listening test where 14 computer compositions were compared with 21 human compositions. Results indicate a slightly lower score for the computer compositions but the differences were statistically insignificant.
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13. |
- Elowsson, Anders, et al.
(författare)
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Estimation of vocal duration in monaural mixtures
- 2014
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Ingår i: Proceedings - 40th International Computer Music Conference, ICMC 2014 and 11th Sound and Music Computing Conference, SMC 2014 - Music Technology Meets Philosophy. - : National and Kapodistrian University of Athens. - 9789604661374 ; , s. 1172-1177
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Konferensbidrag (refereegranskat)abstract
- In this study, the task of vocal duration estimation in monaural music mixtures is explored. We show how presently available algorithms for source separation and predominant f0 estimation can be used as a front end from which features can be extracted. A large set of features is presented, devised to connect different vocal cues to the presence of vocals. Two main cues are utilized; the voice is neither stable in pitch nor in timbre. We evaluate the performance of the model by estimating the length of the vocal regions of the mixtures. To facilitate this, a new set of annotations to a widely adopted data set is developed and made available to the community. The proposed model is able to explain about 78 % of the variance in vocal region length. In a classification task, where the excerpts are classified as either vocal or non-vocal, the model has an accuracy of about 0.94.
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14. |
- Elowsson, Anders, et al.
(författare)
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Long-term Average Spectrum in Popular Music and its Relation to the Level of the Percussion
- 2017
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Ingår i: AES 142nd Convention, Berlin, Germany.
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Konferensbidrag (refereegranskat)abstract
- The spectral distribution of music audio has an important influence on listener perception, but large-scale charac- terizations are lacking. Therefore, the long-term average spectrum (LTAS) was analyzed for a large dataset of popular music. The mean LTAS was computed, visualized, and then approximated with two quadratic fittings. The fittings were subsequently used to derive the spectrum slope. By applying harmonic/percussive source sepa- ration, the relationship between LTAS and percussive prominence was investigated. A clear relationship was found; tracks with more percussion have a relatively higher LTAS in the bass and high frequencies. We show how this relationship can be used to improve targets in automatic equalization. Furthermore, we assert that variations in LTAS between genres is mainly a side-effect of percussive prominence.
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15. |
- Elowsson, Anders, et al.
(författare)
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Modeling Music Modality with a Key-Class Invariant Pitch Chroma CNN
- 2019
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Ingår i: Proceedings of the 20th International Society for Music Information Retrieval Conference, ISMIR 2019.
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Konferensbidrag (refereegranskat)abstract
- This paper presents a convolutional neural network (CNN) that uses input from a polyphonic pitch estimation system to predict perceived minor/major modality in music audio. The pitch activation input is structured to allow the first CNN layer to compute two pitch chromas focused on dif-ferent octaves. The following layers perform harmony analysis across chroma and time scales. Through max pooling across pitch, the CNN becomes invariant with re-gards to the key class (i.e., key disregarding mode) of the music. A multilayer perceptron combines the modality ac-tivation output with spectral features for the final predic-tion. The study uses a dataset of 203 excerpts rated by around 20 listeners each, a small challenging data size re-quiring a carefully designed parameter sharing. With an R2 of about 0.71, the system clearly outperforms previous sys-tems as well as individual human listeners. A final ablation study highlights the importance of using pitch activations processed across longer time scales, and using pooling to facilitate invariance with regards to the key class.
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16. |
- Elowsson, Anders, et al.
(författare)
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Modeling the perception of tempo
- 2015
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Ingår i: Journal of the Acoustical Society of America. - : Acoustical Society of America (ASA). - 0001-4966 .- 1520-8524. ; 137:6, s. 3163-3177
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Tidskriftsartikel (refereegranskat)abstract
- A system is proposed in which rhythmic representations are used to model the perception of tempo in music. The system can be understood as a five-layered model, where representations are transformed into higher-level abstractions in each layer. First, source separation is applied (Audio Level), onsets are detected (Onset Level), and interonset relationships are analyzed (Interonset Level). Then, several high-level representations of rhythm are computed (Rhythm Level). The periodicity of the music is modeled by the cepstroid vector-the periodicity of an interonset interval (IOI)-histogram. The pulse strength for plausible beat length candidates is defined by computing the magnitudes in different IOI histograms. The speed of the music is modeled as a continuous function on the basis of the idea that such a function corresponds to the underlying perceptual phenomena, and it seems to effectively reduce octave errors. By combining the rhythmic representations in a logistic regression framework, the tempo of the music is finally computed (Tempo Level). The results are the highest reported in a formal benchmarking test (2006-2013), with a P-Score of 0.857. Furthermore, the highest results so far are reported for two widely adopted test sets, with an Acc1 of 77.3% and 93.0% for the Songs and Ballroom datasets.
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17. |
- Elowsson, Anders, et al.
(författare)
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Modelling Perception of Speed in Music Audio
- 2013
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Ingår i: Proceedings of the Sound and Music Computing Conference 2013. - 9789175018317 ; , s. 735-741
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Konferensbidrag (refereegranskat)abstract
- One of the major parameters in music is the overall speed of a musical performance. Speed is often associated with tempo, but other factors such as note density (onsets per second) seem to be important as well. In this study, a computational model of speed in music audio has been developed using a custom set of rhythmic features. The original audio is first separated into a harmonic part and a percussive part and onsets are extracted separately from the different layers. The characteristics of each onset are determined based on frequency content as well as perceptual salience using a clustering approach. Using these separated onsets a set of eight features including a tempo estimation are defined which are specifically designed for modelling perceived speed. In a previous study 20 listeners rated the speed of 100 ringtones consisting mainly of popular songs, which had been converted from MIDI to audio. The ratings were used in linear regression and PLS regression in order to evaluate the validity of the model as well as to find appropriate features. The computed audio features were able to explain about 90 % of the variability in listener ratings.
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18. |
- Elowsson, Anders, et al.
(författare)
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Modelling the Speed of Music Using Features from Harmonic/Percussive Separated Audio
- 2013
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Ingår i: Proceedings of the 14th International Society for Music Information Retrieval Conference. - : International Society for Music Information Retrieval. - 9780615900650 ; , s. 481-486
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Konferensbidrag (refereegranskat)abstract
- One of the major parameters in music is the overall speed of a musical performance. In this study, a computational model of speed in music audio has been developed using a custom set of rhythmic features. Speed is often associ-ated with tempo, but as shown in this study, factors such as note density (onsets per second) and spectral flux are important as well. The original audio was first separated into a harmonic part and a percussive part and the fea-tures were extracted separately from the different layers. In previous studies, listeners had rated the speed of 136 songs, and the ratings were used in a regression to evalu-ate the validity of the model as well as to find appropriate features. The final models, consisting of 5 or 8 features, were able to explain about 90% of the variation in the training set, with little or no degradation for the test set.
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19. |
- Elowsson, Anders, et al.
(författare)
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Predicting the perception of performed dynamics in music audio with ensemble learning
- 2017
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Ingår i: Journal of the Acoustical Society of America. - : Acoustical Society of America (ASA). - 0001-4966 .- 1520-8524. ; 141:3, s. 2224-2242
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Tidskriftsartikel (refereegranskat)abstract
- By varying the dynamics in a musical performance, the musician can convey structure and different expressions. Spectral properties of most musical instruments change in a complex way with the performed dynamics, but dedicated audio features for modeling the parameter are lacking. In this study, feature extraction methods were developed to capture relevant attributes related to spectral characteristics and spectral fluctuations, the latter through a sectional spectral flux. Previously, ground truths ratings of performed dynamics had been collected by asking listeners to rate how soft/loud the musicians played in a set of audio files. The ratings, averaged over subjects, were used to train three different machine learning models, using the audio features developed for the study as input. The highest result was produced from an ensemble of multilayer perceptrons with an R2 of 0.84. This result seems to be close to the upper bound, given the estimated uncertainty of the ground truth data. The result is well above that of individual human listeners of the previous listening experiment, and on par with the performance achieved from the average rating of six listeners. Features were analyzed with a factorial design, which highlighted the importance of source separation in the feature extraction.
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20. |
- Friberg, Anders, et al.
(författare)
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Cross-cultural aspects of perceptual features in K-pop : A pilot study comparing Chinese and Swedish listeners
- 2017
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Ingår i: 2017 ICMC/EMW - 43rd International Computer Music Conference and the 6th International Electronic Music Week. - : Shanghai Conservatory of Music. - 9780984527465 ; , s. 291-296
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Konferensbidrag (refereegranskat)abstract
- In previous studies it has been shown that perceptual features can be used as an intermediate representation in music processing to model higher-level semantic descriptions. In this pilot study, we focused on the cross-cultural aspect of such perceptual features, by asking both Chinese and Swedish listeners to rate a set of K-Pop samples using a web-based questionnaire. The music samples were selected from a larger set, previously rated in terms of different emotion labels. The selection procedure of the subset was carefully designed to maximize both the variation of emotion and genre. The listeners rated eight perceptual features: dissonance, speed, rhythmic complexity, rhythmic clarity, articulation, harmonic complexity, modality, and pitch. The results indicated a small but significant difference in the two groups, regarding the average speed and rhythmic complexity. In particular the perceived speed of hip hop was different for the two groups. We discuss the overall consistency of the ratings using this methodology in relation to the interface, selection and number of subjects.
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21. |
- Friberg, Anders, Professor, et al.
(författare)
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Prediction of three articulatory categories in vocal sound imitations using models for auditory receptive fields
- 2018
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Ingår i: Journal of the Acoustical Society of America. - : Acoustical Society of America (ASA). - 0001-4966 .- 1520-8524. ; 144:3, s. 1467-1483
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Tidskriftsartikel (refereegranskat)abstract
- Vocal sound imitations provide a new challenge for understanding the coupling between articulatory mechanisms and the resulting audio. In this study, we have modeled the classification of three articulatory categories, phonation, supraglottal myoelastic vibrations, and turbulence from audio recordings. Two data sets were assembled, consisting of different vocal imitations by four professional imitators and four non-professional speakers in two different experiments. The audio data were manually annotated by two experienced phoneticians using a detailed articulatory description scheme. A separate set of audio features was developed specifically for each category using both time-domain and spectral methods. For all time-frequency transformations, and for some secondary processing, the recently developed Auditory Receptive Fields Toolbox was used. Three different machine learning methods were applied for predicting the final articulatory categories. The result with the best generalization was found using an ensemble of multilayer perceptrons. The cross-validated classification accuracy was 96.8 % for phonation, 90.8 % for supraglottal myoelastic vibrations, and 89.0 % for turbulence using all the 84 developed features. A final feature reduction to 22 features yielded similar results.
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22. |
- Friberg, Anders, et al.
(författare)
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Using listener-based perceptual features as intermediate representations in music information retrieval
- 2014
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Ingår i: Journal of the Acoustical Society of America. - : Acoustical Society of America (ASA). - 0001-4966 .- 1520-8524. ; 136:4, s. 1951-1963
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Tidskriftsartikel (refereegranskat)abstract
- The notion of perceptual features is introduced for describing general music properties based on human perception. This is an attempt at rethinking the concept of features, aiming to approach the underlying human perception mechanisms. Instead of using concepts from music theory such as tones, pitches, and chords, a set of nine features describing overall properties of the music was selected. They were chosen from qualitative measures used in psychology studies and motivated from an ecological approach. The perceptual features were rated in two listening experiments using two different data sets. They were modeled both from symbolic and audio data using different sets of computational features. Ratings of emotional expression were predicted using the perceptual features. The results indicate that (1) at least some of the perceptual features are reliable estimates; (2) emotion ratings could be predicted by a small combination of perceptual features with an explained variance from 75% to 93% for the emotional dimensions activity and valence; (3) the perceptual features could only to a limited extent be modeled using existing audio features. Results clearly indicated that a small number of dedicated features were superior to a "brute force" model using a large number of general audio features.
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23. |
- Friberg, Anders, et al.
(författare)
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Using perceptually defined music features in music information retrieval
- 2014
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- In this study, the notion of perceptual features is introduced for describing general music properties based on human perception. This is an attempt at rethinking the concept of features, in order to understand the underlying human perception mechanisms. Instead of using concepts from music theory such as tones, pitches, and chords, a set of nine features describing overall properties of the music was selected. They were chosen from qualitative measures used in psychology studies and motivated from an ecological approach. The selected perceptual features were rated in two listening experiments using two different data sets. They were modeled both from symbolic (MIDI) and audio data using different sets of computational features. Ratings of emotional expression were predicted using the perceptual features. The results indicate that (1) at least some of the perceptual features are reliable estimates; (2) emotion ratings could be predicted by a small combination of perceptual features with an explained variance up to 90%; (3) the perceptual features could only to a limited extent be modeled using existing audio features. The results also clearly indicated that a small number of dedicated features were superior to a 'brute force' model using a large number of general audio features.
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24. |
- Maarbjerg, Sabine F., et al.
(författare)
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Piperacillin pharmacokinetics and target attainment in children with cancer and fever : Can we optimize our dosing strategy?
- 2019
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Ingår i: Pediatric Blood & Cancer. - : Wiley. - 1545-5009 .- 1545-5017. ; 66:6
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Tidskriftsartikel (refereegranskat)abstract
- Background Data on piperacillin-tazobactam pharmacokinetics and optimal dosing in children with cancer and fever are limited. Our objective was to investigate piperacillin pharmacokinetics and the probability of target attainment (PTA) with standard intermittent administration (IA), and to simulate PTA in other dosing regimens.Procedure This prospective pharmacokinetic study was conducted from April 2016 to January 2018. Children with cancer receiving empiric piperacillin-tazobactam to treat infections were included. Piperacillin-tazobactam 100 mg/kg was infused over 5 min every 8 hours (IA). An optimized sample schedule provided six blood samples per subject for piperacillin concentration determination. The evaluated targets included: (1) 100% time of free piperacillin concentration above the minimum inhibitory concentration (fT > MIC) and (2) 50% fT > 4x MIC. MIC50 and MIC90 were defined based on an intrainstitutional MIC range.Results A total of 482 piperacillin concentrations were obtained from 43 children (aged 1-18 years) during 89 fever episodes. Standard IA resulted in insufficient target attainment, with significant differences in piperacillin pharmacokinetics for different body weights. Median fT > MIC was 61.2%, 53.5%, and 36.3% for MIC50 (2.0 mg/L), MIC90 (4.0 mg/L), and breakpoint for Pseudomonas aeruginosa (16.0 mg/L), respectively. Correspondingly, the median fT > 4x MIC was 43%, 36.3%, and 20.1%. Simulations showed that only continuous infusion reached a PTA of 95% for MIC = 16.0 mg/L, while extended infusion lasting half of the dosing interval reached a PTA of 95% for MIC <= 8 mg/L.Conclusions Our data revealed insufficient PTA with standard IA of piperacillin-tazobactam in children with cancer and fever. Alternative dosing strategies, preferably continuous infusion, are required to ensure adequate PTA.
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25. |
- Masko, Jonas, et al.
(författare)
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Software tools for automatic music performance
- 2014
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Ingår i: 1st international workshop on computer and robotic Systems for Automatic Music Performance (SAMP14). - Venice.
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Konferensbidrag (refereegranskat)abstract
- Two new computer programs are presented for the purpose of facilitating new research in music performance modeling. Director Musices (DM) is a new an implementation of the user interface for the KTH rule system. It includes a new integrated player and several other improvements. The automatic sampler facilitates the sampling of a MIDI-controlled instrument, such as the Disklavier piano from Yamaha. Both programs are open source, cross-platform written in Java and in the case of DM including also different lisp dialects.
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26. |
- Nielsen, Niklas, et al.
(författare)
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Target temperature management after out-of-hospital cardiac arrest-a randomized, parallel-group, assessor-blinded clinical trial-rationale and design
- 2012
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Ingår i: American Heart Journal. - : Elsevier. - 0002-8703 .- 1097-6744. ; 163:4, s. 541-548
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Tidskriftsartikel (refereegranskat)abstract
- Background Experimental animal studies and previous randomized trials suggest an improvement in mortality and neurologic function with induced hypothermia after cardiac arrest. International guidelines advocate the use of a target temperature management of 32 degrees C to 34 degrees C for 12 to 24 hours after resuscitation from out-of-hospital cardiac arrest. A systematic review indicates that the evidence for recommending this intervention is inconclusive, and the GRADE level of evidence is low. Previous trials were small, with high risk of bias, evaluated select populations, and did not treat hyperthermia in the control groups. The optimal target temperature management strategy is not known. less thanbrgreater than less thanbrgreater thanMethods The TTM trial is an investigator-initiated, international, randomized, parallel-group, and assessor-blinded clinical trial designed to enroll at least 850 adult, unconscious patients resuscitated after out-of-hospital cardiac arrest of a presumed cardiac cause. The patients will be randomized to a target temperature management of either 33 degrees C or 36 degrees C after return of spontaneous circulation. In both groups, the intervention will last 36 hours. The primary outcome is all-cause mortality at maximal follow-up. The main secondary outcomes are the composite outcome of all-cause mortality and poor neurologic function (cerebral performance categories 3 and 4) at hospital discharge and at 180 days, cognitive status and quality of life at 180 days, assessment of safety and harm. less thanbrgreater than less thanbrgreater thanDiscussion The TTM trial will investigate potential benefit and harm of 2 target temperature strategies, both avoiding hyperthermia in a large proportion of the out-of-hospital cardiac arrest population.
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27. |
- Sandström, Nadia, 1995-, et al.
(författare)
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Addition of benzylpenicillin to antibiotic prophylaxis reduces deep sternal wound infection after cardiac surgery
- 2021
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Ingår i: Infection Prevention in Practice. - : Elsevier. - 2590-0889. ; 3:3
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: In Sweden, cloxacillin is recommended as the sole antibiotic prophylaxis for prevention of surgical site infections after cardiac surgery. Cutibacterium acnes, formerly Propionibacterium acnes, has been shown to be present in the surgical wound. Formerly an overlooked pathogen, there are increasing reports that C acnes can cause surgical site infections, including sternal wound infections. Cloxacillin may not be optimal for prevention of C acnes infection, therefore benzylpenicillin was added to our routine intraoperative prophylaxis in 2015. The aim of this study was to investigate the effect of benzylpenicillin on incidence of sternal wound infection.Methods: We included 3920 consecutive patients that underwent cardiac surgery via median sternotomy at our centre from 2009 thru 2018. All patients were followed up two months postoperatively. The rate of sternal wound infection before and after 2015 were compared. Logistic multivariable analysis was used to adjust for potential confounders.Results: The mean incidence of sternal wound infection that required surgical revision decreased from 4.7% to 1.7% after addition of benzylpenicillin (p < 0.001). Significant decrease was seen in sternal wound infections caused by Coagulase negative staphylococci, either alone (p<0.001) or concomitant with C acnes (p=0.008). Addition of benzylpenicillin remained independently associated with the reduction of sternal wound infections in the multivariable analysis (OR=0.36 CI=0.23-0.56, p<0.001).Conclusions: Addition of benzylpenicillin was associated with a reduction in surgically treated infections and might be effective against infection caused by CoNS with and without co-infection by C acnes, although the exact underlying mechanism is unknown.
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28. |
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29. |
- Sönnerfors, Pernilla, et al.
(författare)
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The challenges of recruiting never-smokers with chronic obstructive pulmonary disease from the large population-based Swedish CArdiopulmonary bioImage study (SCAPIS) cohort.
- 2024
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Ingår i: European Clinical Respiratory Journal. - : Taylor & Francis. - 2001-8525. ; 11:1, s. 2372903-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: A substantial proportion of individuals with COPD have never smoked, and it is implied to be more common than previously anticipated but poorly studied.AIM: To describe the process of recruitment of never-smokers with COPD from a population-based cohort (n = 30 154).METHODS: We recruited never-smokers with COPD, aged 50-75 years, from six University Hospitals, based on: 1) post broncho-dilator forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) < 0.70 and 2) FEV1 50-100% of predicted value and 3) being never-smokers (self-reported). In total 862 SCAPIS participants were identified, of which 652 were reachable and agreed to a first screening by telephone. Altogether 128 (20%) were excluded due to previous smoking or declined participation. We also applied a lower limit of normal (LLN) of FEV1/FVC (z-score<-1.64) according to the Global Lung Initiative to ensure a stricter definition of airflow obstruction.RESULTS: Data on respiratory symptoms, health status, and medical history were collected from 492 individuals, since 32 were excluded at a second data review (declined or previous smoking), prior to the first visit. Due to not matching the required lung function criteria at a second spirometry, an additional 334 (68%) were excluded. These exclusions were by reason of: FEV1/FVC ≥0.7 (49%), FEV1 > 100% of predicted (26%) or z-score ≥ -1,64 (24%). Finally, 154 never-smokers with COPD were included: 56 (36%) women, (mean) age 60 years, FEV1 84% of predicted, FEV1/FVC: 0.6, z-score: -2.2, Oxygen saturation: 97% and BMI: 26.8 kg/m2.CONCLUSIONS: The challenges of a recruitment process of never-smokers with COPD were shown, including the importance of correct spirometry testing and strict inclusion criteria. Our findings highlight the importance of repeated spirometry assessments for improved accuracy in diagnosing COPD.
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30. |
- Taha, Amar, 1978, et al.
(författare)
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New-Onset Atrial Fibrillation After Coronary Artery Bypass Grafting and Long-Term Outcome: A Population-Based Nationwide Study From the SWEDEHEART Registry.
- 2021
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Ingår i: Journal of the American Heart Association. - 2047-9980. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Background The long-term impact of new-onset postoperative atrial fibrillation (POAF) after coronary artery bypass grafting and the benefit of early-initiated oral anticoagulation (OAC) in patients with POAF are uncertain. Methods and Results All patients who underwent coronary artery bypass grafting without preoperative atrial fibrillation in Sweden from 2007 to 2015 were included in a population-based study using data from 4 national registries: SWEDEHEART (Swedish Web System for Enhancement and Development of Evidence-based Care in Heart Disease Evaluated According to Recommended Therapies), National Patient Registry, Dispensed Drug Registry, and Cause of Death Registry. POAF was defined as any new-onset atrial fibrillation during the first 30 postoperative days. Cox regression models (adjusted for age, sex, comorbidity, and medication) were used to assess long-term outcome in patients with and without POAF, and potential associations between early-initiated OAC and outcome. In a cohort of 24523 patients with coronary artery bypass grafting, POAF occurred in 7368 patients (30.0%), and 1770 (24.0%) of them were prescribed OAC within 30days after surgery. During follow-up (median 4.5years, range 0‒9years), POAF was associated with increased risk of ischemic stroke (adjusted hazard ratio [aHR] 1.18 [95% CI, 1.05‒1.32]), any thromboembolism (ischemic stroke, transient ischemic attack, or peripheral arterial embolism) (aHR 1.16, 1.05‒1.28), heart failure hospitalization (aHR 1.35, 1.21‒1.51), and recurrent atrial fibrillation (aHR 4.16, 3.76‒4.60), but not with all-cause mortality (aHR 1.08, 0.98‒1.18). Early initiation of OAC was not associated with reduced risk of ischemic stroke or any thromboembolism but with increased risk for major bleeding (aHR 1.40, 1.08‒1.82). Conclusions POAF after coronary artery bypass grafting is associated with negative prognostic impact. The role of early OAC therapy remains unclear. Studies aiming at reducing the occurrence of POAF and its consequences are warranted.
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31. |
- Taha, Amar, 1978, et al.
(författare)
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Stroke Risk Stratification in Patients With Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting.
- 2022
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Ingår i: Journal of the American Heart Association. - 2047-9980. ; 11:10
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Tidskriftsartikel (refereegranskat)abstract
- Background The CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75years, diabetes, previous stroke or TIA [transient ischemic attack], vascular disease, age 65 to 74years, sex category female; 2 indicates 2 points, otherwise 1 point) scoring system is recommended to guide decisions on oral anticoagulation therapy for stroke prevention in patients with nonsurgery atrial fibrillation. A score ≥1 in men and ≥2 in women, corresponding to an annual stroke risk exceeding 1%, warrants long-term oral anticoagulation provided the bleeding risk is acceptable. However, in patients with new-onset postoperative atrial fibrillation, the optimal risk stratification method is unknown. The aim of this study was therefore to evaluate the CHA2DS2-VASc scoring system for estimating the 1-year ischemic stroke risk in patients with new-onset postoperative atrial fibrillation after coronary artery bypass grafting. Methods and Results All patients with new-onset postoperative atrial fibrillation and without oral anticoagulation after first-time isolated coronary artery bypass grafting performed in Sweden during 2007 to 2017 were eligible for this registry-based observational cohort study. The 1-year ischemic stroke rate at each step of the CHA2DS2-VASc score was estimated using a Kaplan-Meier estimator. Of the 6368 patients included (mean age, 69.9years; 81% men), >97% were treated with antiplatelet drugs. There were 147 ischemic strokes during the first year of follow-up. The ischemic stroke rate at 1year was 0.3%, 0.7%, and 1.5% in patients with CHA2DS2-VASc scores of 1, 2, and 3, respectively, and ≥2.3% in patients with a score ≥4. A sensitivity analysis, with the inclusion of patients on anticoagulants, was performed and supported the primary results. Conclusions Patients with new-onset atrial fibrillation after coronary artery bypass grafting and a CHA2DS2-VASc score <3 have such a low 1-year risk for ischemic stroke that oral anticoagulation therapy should probably be avoided.
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32. |
- Thorsted, Anders, et al.
(författare)
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Population pharmacokinetics of piperacillin in febrile children receiving cancer chemotherapy : the impact of body weight and target on an optimal dosing regimen
- 2019
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Ingår i: Journal of Antimicrobial Chemotherapy. - : Oxford University Press (OUP). - 0305-7453 .- 1460-2091. ; 74:10, s. 2984-2993
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Tidskriftsartikel (refereegranskat)abstract
- Background The β-lactam antibiotic piperacillin (in combination with tazobactam) is commonly chosen for empirical treatment of suspected bacterial infections. However, pharmacokinetic variability among patient populations and across ages leads to uncertainty when selecting a dosing regimen to achieve an appropriate pharmacodynamic target.Objectives To guide dosing by establishing a population pharmacokinetic model for unbound piperacillin in febrile children receiving cancer chemotherapy, and to assess pharmacokinetic/pharmacodynamic target attainment (100% fT>1xMIC and 50% fT>4xMIC) and resultant exposure, across body weights.Methods Forty-three children admitted for 89 febrile episodes contributed 482 samples to the pharmacokinetic analysis. The typical doses required for target attainment were compared for various dosing regimens, in particular prolonged infusions, across MICs and body weights.Results A two-compartment model with inter-fever-episode variability in CL, and body weight included through allometry, described the data. A high CL of 15.4L/h (70kg) combined with high glomerular filtration rate (GFR) values indicated rapid elimination and hyperfiltration. The target of 50% fT>4xMIC was achieved for an MIC of 4.0mg/L in a typical patient with extended infusions of 2-3 (q6h) or 3-4 (q8h)h, at or below the standard adult dose (75 and 100mg/kg/dose for q6h and q8h, respectively). Higher doses or continuous infusion were needed to achieve 100% fT>1xMIC due to the rapid piperacillin elimination.Conclusions The licensed dose for children with febrile neutropenia (80mg/kg q6h as a 30min infusion) performs poorly for attainment of fT>MIC pharmacokinetic/pharmacodynamic targets. Given the population pharmacokinetic profile, feasible dosing regimens with reasonable exposure are continuous infusion (100% fT>1xMIC) or prolonged infusions (50% fT>4xMIC).
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33. |
- Addessi, Anna Rita, et al.
(författare)
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Child-Computer Interaction at the Beginner Stage of Music Learning : Effects of Reflexive Interaction on Children's Musical Improvisation
- 2017
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Ingår i: Frontiers in Psychology. - : Frontiers Research Foundation. - 1664-1078. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- In this article childrens musical improvisation is investigated through the reflexive interaction paradigm. We used a particular system, the MIROR-Impro, implemented in the framework of the MIROR project (EC-FP7), which is able to reply to the child playing a keyboard by a reflexive output, mirroring (with repetitions and variations) her/his inputs. The study was conducted in a public primary school, with 47 children, aged 6-7. The experimental design used the convergence procedure, based on three sample groups allowing us to verify if the reflexive interaction using the MIROR-Impro is necessary and/or sufficient to improve the childrens abilities to improvise. The following conditions were used as independent variables: to play only the keyboard, the keyboard with the MIROR-Impro but with not-reflexive reply, the keyboard with the MIROR-Impro with reflexive reply. As dependent variables we estimated the childrens ability to improvise in solos, and in duets. Each child carried out a training program consisting of 5 weekly individual 12 min sessions. The control group played the complete package of independent variables; Experimental Group 1 played the keyboard and the keyboard with the MIROR-Impro with not-reflexive reply; Experimental Group 2 played only the keyboard with the reflexive system. One week after, the children were asked to improvise a musical piece on the keyboard alone (Solo task), and in pairs with a friend (Duet task). Three independent judges assessed the Solo and the Duet tasks by means of a grid based on the TAI-Test for Ability to Improvise rating scale. The EG2, which trained only with the reflexive system, reached the highest average results and the difference with EG1, which did not used the reflexive system, is statistically significant when the children improvise in a duet. The results indicate that in the sample of participants the reflexive interaction alone could be sufficient to increase the improvisational skills, and necessary when they improvise in duets. However, these results are in general not statistically significant. The correlation between Reflexive Interaction and the ability to improvise is statistically significant. The results are discussed on the light of the recent literature in neuroscience and music education.
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34. |
- Addessi, A. R., et al.
(författare)
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Corrigendum : Child-computer interaction at the beginner stage of music learning: Effects of reflexive interaction on children's musical improvisation [Front. Psychol.8 (2017)(65)]. Doi: 10.3389/fpsyg.2017.00065
- 2017
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Ingår i: Frontiers in Psychology. - : Frontiers Media S.A.. - 1664-1078. ; 8:MAR
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Tidskriftsartikel (refereegranskat)abstract
- A corrigendum on Corrigendum: Child-Computer Interaction at the Beginner Stage of Music Learning: Effects of Reflexive Interaction on Children's Musical Improvisation by Addessi, A. R., Anelli, F., Benghi, D., and Friberg, A. (2017). Front. Psychol. 8:65. doi: 10.3389/fpsyg.2017.00065 In the original article, there was an error. "she plays C3" was used instead of "it plays C3." A correction has been made to Observation and Theoretical Framework of Reflexive Interaction, paragraph 3: The little girl plays two consecutive notes, C2 and A2, and then stops to wait for the response of the system. The system responds by repeating the same notes. The child then play a single note, G2, and the system responds with a single note but this time introduces a variation: it plays C3, thus introducing a higher register. The girl, following the change introduced by the system, moves toward the higher register and plays a variant of the initial pattern, namely: D2-A2-E2-C3, and introduces a particular rhythm pattern. This "reflexive" event marks the beginning of a dialogue based on repetition and variation: the rhythmic-melodic pattern will be repeated and varied by both the system and the child in consecutive exchanges, until acquiring the form of a complete musical phrase. At some point in the dialogue, the child begins to accompany the system's response with arm movements synchronized with the rhythmic-melodic patterns, creating a kind of music-motor composition. In addition, EG1 and EG2 are incorrectly referred to within the text. A correction has been made to Duet Task, sub-section Results for Each Evaluative Criterion of the Duet Task, paragraph Reflexive Interaction: The data of Reflexive Interaction show that the EG2 obtained the highest score (4.17), followed by the CG (3.33) and the EG1 (2.61); see Table 6 and Figure 7. The difference between EG2, which only use the system with reflexive interaction, and EG1, which did not use the system with reflexive interaction, is significant (p = 0.043). Therefore, it could be said that the use of MIROR-Impro can enhance the use of the reflexive behaviors: mirroring, turn-taking, and co-regulation. We observed a statistically significant correlation between the Reflexive Interaction and the total score (r = 0.937; p < 0.01), and all other evaluative criteria, with correlations ranging from r = 0.87 (p < 0.01) for Musical Quality to r = 0.92 (p < 0.01) for Musical Organization. Thus, the higher the children's use of reflexive interaction, the better their results in each criterion and in the ability to improvise. This result can support the hypothesis that reflexive interaction is a fundamental component of musical improvised dialog. Instead, although the differences between the CG and the Experimental Groups 1 and 2 indicate that the use of the MIROR Impro appears to be "necessary" (CG > EG1) and "sufficient" (CG < EG2) to improve the ability to improvise, we cannot generalize these results because the results are not statistically significant (t-test, comparing CG and EG1: p = 0.388; CG and EG2: p = 0.285). Finally, due to the resolution of Figures 5-9 being low, they have been replaced with new figures with a higher resolution. The corrected Figures, Figures 5-9 appear below. The authors apologize for these errors and state that these do not change the scientific conclusions of the article in any way.
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35. |
- Ahlberg, Erik, et al.
(författare)
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"Vi klimatforskare stödjer Greta och skolungdomarna"
- 2019
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Ingår i: Dagens nyheter (DN debatt). - 1101-2447.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- DN DEBATT 15/3. Sedan industrialiseringens början har vi använt omkring fyra femtedelar av den mängd fossilt kol som får förbrännas för att vi ska klara Parisavtalet. Vi har bara en femtedel kvar och det är bråttom att kraftigt reducera utsläppen. Det har Greta Thunberg och de strejkande ungdomarna förstått. Därför stödjer vi deras krav, skriver 270 klimatforskare.
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36. |
- Ahlsson, Anders, 1962-, et al.
(författare)
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An angry cat causing Pasteurella multocida endocarditis and aortic valve replacement : A case report
- 2016
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Ingår i: International Journal of Surgery Case Reports. - : Elsevier. - 2210-2612. ; 24, s. 91-93
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Cat bite infections usually involve a mix of anaerobic and aerobic bacteria including species of Pasteurella, Streptococcus, Staphylococcus, Bacteroides, and Fusobacterium. We report a case of Pasteurella multocida infection from cat bites leading to endocarditis and subsequent aortic valve replacement.PRESENTATION OF CASE: A 70-year-old male was admitted because of fever, tachycardia, and malaise. He had a history of alcohol abuse and was living alone with a cat in a rural area. A sepsis of unknown origin was suspected, and intravenous treatment with gentamicin and cefotaxime was initiated. Blood cultures yielded Pasteurella multocida, and the patient history revealed repeated cat bites. After four days, the patient was discharged with oral penicillin V treatment. Two weeks later, the patient returned with fever and a new systolic murmur. An aortic valve endocarditis was diagnosed, and it became clear that the patient had not completed the prescribed penicillin V treatment. The patient underwent a biological aortic valve replacement with debridement of an annular abscess, and the postoperative course was uneventful.DISCUSSION: Endocarditis due to Pasteurella is extremely rare, and there are only a few reports in the literature. Predisposing factors in the present case were alcohol abuse and reduced compliance to treatment.CONCLUSION: Cat bites are often deep, and in rare circumstances can lead to life-threatening endocarditis. Proper surgical revision, antibiotic treatment, and patient compliance are necessary components in patient care to avoid this complication.
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37. |
- Almroth, Henrik, et al.
(författare)
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Safety of flecainide for atrial fibrillation : the Swedish atrial fibrillation cohort study
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Background Little is known about the safety of flecainide in atrial fibrillation (AF). Whether current flecainide treatment practice in Sweden is associated with increased mortality compared to treatment with beta-blockers alone was investigated in patients with atrial fibrillation (AF).Methods and Results A total of 182,678 patients diagnosed with AF between 1 July 2005 and 31 December 2008 were identified through the Swedish National Hospital Discharge Register. These data were matched to data from the Prescribed Drug Register and information about death from the Total Population Register. The primary outcome was all cause mortality at the end of the study period, 1 Feb 2010. Flecainide was prescribed to 5381 patients (2.9%), and 64,918 patients (45.7%) received beta-blockers only. During follow-up, 2.8% and 30.8% of these patients died, respectively. After coarsened and exact matching, 2,178 patients (1.2% of total) on flecainide and beta-blockers had more similar baseline characteristics to 27,313 patients (15.3% of total) on beta-blockers only. In the main analysis, flecainide exposure was not associated with increased mortality (OR 0.27, 95% CI 0.21-0.36,P<0.001). In the matched flecainide population, 205 (9.4%) patients had underlying structural heart disease. Sixteen (28.6%) of the flecainide-exposed patients who died had structural heart disease. The patients who only received flecainide (n=264) had higher mortality rate than the patients who received flecainide and beta-blockers (6.8 versus 2.6%,P<0.001).Conclusions Flecainide is not associated with increased mortality in patients with AF compared to beta-blockers alone. Patients who die after receiving flecainide often have structural heart disease.
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38. |
- Alström, Ulrica, et al.
(författare)
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Risk factors for re-exploration due to bleeding after coronary artery bypass grafting
- 2012
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Ingår i: Scandinavian Cardiovascular Journal. - : Informa Healthcare. - 1401-7431 .- 1651-2006. ; 46:1, s. 39-44
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The study aimed to investigate relevant clinical risk factors for re-exploration due to bleeding after primary coronary artery bypass graft (CABG) surgery, and to evaluate the influence of antiplatelet and antifibrinolytic drugs.Design: Three retrospective analyses were performed on patients who underwent CABG: (1) Logistic regression was used to identify clinical risk factors for re-exploration (n = 3000). (2) A case-control study (n = 228) was used to obtain information on exposure of antithrombotic and hemostatic therapy. (3) Based on exposure to antiplatelet and antifibrinolytic therapy, and odds ratios (ORs) in multivariate logistic models, the proportion of re-explorations attributed to these drugs was calculated.Results: A receiver operating characteristic curve was created for clinical risk factors. The C-index was 0.64, indicating limited ability to predict re-exploration for bleeding. Clopidogrel was the only drug influencing the risk of re-exploration (OR 3.2, 95% CI 1.7-5.9). The harmful effect of clopidogrel was confirmed in multivariate model (OR 4.7, 95% CI 2.2-9.9), and aprotinin had a protective effect of the same magnitude (OR 0.2, 95% CI 0.1-0.6).Conclusions: Clopidogrel is an essential risk factor for re-exploration due to bleeding, and attributable to at least one-quarter of surveyed cases. Aside from pharmaceuticals, there are no strong clinical risk factors.
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39. |
- Arbeus, Mikael, et al.
(författare)
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Milrinone Increases Flow in Coronary Artery Bypass Grafts After Cardiopulmonary Bypass : A Prospective, Randomized, Double-Blind, Placebo-Controlled Study
- 2009
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Ingår i: Journal of Cardiothoracic and Vascular Anesthesia. - : Elsevier BV. - 1053-0770 .- 1532-8422. ; 23:1, s. 48-53
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To compare the effects of a bolus of milrinone, 50 mu g/kg, versus placebo on flow in coronary artery bypass grafts after cardiopulmonary bypass (CPB). Design: A prospective, randomized, double-blind study. Setting: A university hospital. Participants: Forty-four patients with stable angina and left ventricular ejection fraction > 30% scheduled for elective coronary artery bypass graft (CABG) surgery were included. Intervention: Patients were randomized to receive 50 mu g/kg of milrinone (n = 22) or placebo (n = 22) after aortic declamping. Measurements and Main Results: The flow in coronary artery bypass grafts was measured with a transit time flow meter at 10 minutes and 30 minutes after termination of CPB. The hemodynamic evaluation included transesophageal echocardiography, mean arterial pressure (MAP), heart rate, and intracavitary measurement of left ventricular end-diastolic pressure (LVEDP). The flow in the saphenous vein grafts was significantly higher in the milrinone group when compared with the placebo group both at 10 and 30 minutes after termination of CPB (p < 0.001). At 10 minutes, the flow was 64.5 +/- 37.4 mL/min (mean +/- standard deviation) and 43.6 +/- 25.7 mL/min in nonsequential vein grafts for milrinone and placebo, respectively. Corresponding values at 30 minutes were 54.8 +/- 29.9 mL/min and 35.3 +/- 22.4 mL/min. The left internal thoracic artery (LITA) flow was higher in the milrinone group but did not reach statistical significance. The fractional area change was higher, and the MAP and calculated pressure gradient (MAP-LVEDP) were lower at 10 minutes in the milrinone group. Conclusion: Milrinone significantly increases the flow in anastomosed saphenous vein grafts after CPB, and has beneficial effects on left ventricular function.
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43. |
- Billig, Håkan, 1955, et al.
(författare)
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Follicular development and apoptosis.
- 2002
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Ingår i: Ernst Schering Research Foundation workshop. - 0947-6075. ; :41, s. 23-41
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Tidskriftsartikel (refereegranskat)
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44. |
- Bisesi, Erica, et al.
(författare)
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A Computational Model of Immanent Accent Salience in Tonal Music
- 2019
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Ingår i: Frontiers in Psychology. - : Frontiers Media S.A.. - 1664-1078. ; 10:317, s. 1-19
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Tidskriftsartikel (refereegranskat)abstract
- Accents are local musical events that attract the attention of the listener, and can be either immanent (evident from the score) or performed (added by the performer). Immanent accents involve temporal grouping (phrasing), meter, melody, and harmony; performed accents involve changes in timing, dynamics, articulation, and timbre. In the past, grouping, metrical and melodic accents were investigated in the context of expressive music performance. We present a novel computational model of immanent accent salience in tonal music that automatically predicts the positions and saliences of metrical, melodic and harmonic accents. The model extends previous research by improving on preliminary formulations of metrical and melodic accents and introducing a new model for harmonic accents that combines harmonic dissonance and harmonic surprise. In an analysis-by-synthesis approach, model predictions were compared with data from two experiments, respectively involving 239 sonorities and 638 sonorities, and 16 musicians and 5 experts in music theory. Average pair-wise correlations between raters were lower for metrical (0.27) and melodic accents (0.37) than for harmonic accents (0.49). In both experiments, when combining all the raters into a single measure expressing their consensus, correlations between ratings and model predictions ranged from 0.43 to 0.62. When different accent categories of accents were combined together, correlations were higher than for separate categories (r = 0.66). This suggests that raters might use strategies different from individual metrical, melodic or harmonic accent models to mark the musical events.
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- Bisesi, Erica, et al.
(författare)
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An accent-based approach to performance rendering: Music theory meets music psychology
- 2011
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Ingår i: Proceedings of ISPS 2011. - Utrecht : the European Association of Conservatoires (AEC). - 9789490306021 ; , s. 27-32
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Konferensbidrag (refereegranskat)abstract
- Accents are local events that attract a listener’s attention and are either evident from the score (immanent) or added by the performer (performed). Immanent accents are associated with grouping, meter, melody, and harmony. In piano music, performed accents involve changes in timing, dynamics, articulation, and pedaling; they vary in amplitude, form, and duration. Performers tend to “bring out” immanent accents by means of performed accents, which attracts the listener’s attention to them. We are mathematically modeling timing and dynamics near immanent accents in a selection of Chopin Preludes using an extended version of Director Musices(DM),a software package for automatic rendering of expressive performance. We are developing DM in a new direction, which allows us to relate expressive features of a performance not only to global or intermediate structural properties, but also accounting for local events.
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- Blennow Nordström, Erik, et al.
(författare)
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Neuropsychological outcome after cardiac arrest : results from a sub-study of the targeted hypothermia versus targeted normothermia after out-of-hospital cardiac arrest (TTM2) trial
- 2023
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Ingår i: Critical Care. - : BioMed Central (BMC). - 1364-8535 .- 1466-609X. ; 27:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Cognitive impairment is common following out-of-hospital cardiac arrest (OHCA), but the nature of the impairment is poorly understood. Our objective was to describe cognitive impairment in OHCA survivors, with the hypothesis that OHCA survivors would perform significantly worse on neuropsychological tests of cognition than controls with acute myocardial infarction (MI). Another aim was to investigate the relationship between cognitive performance and the associated factors of emotional problems, fatigue, insomnia, and cardiovascular risk factors following OHCA.METHODS: This was a prospective case-control sub-study of The Targeted Hypothermia versus Targeted Normothermia after Out-of-Hospital Cardiac Arrest (TTM2) trial. Eight of 61 TTM2-sites in Sweden, Denmark, and the United Kingdom included adults with OHCA of presumed cardiac or unknown cause. A matched non-arrest control group with acute MI was recruited. At approximately 7 months post-event, we administered an extensive neuropsychological test battery and questionnaires on anxiety, depression, fatigue, and insomnia, and collected information on the cardiovascular risk factors hypertension and diabetes.RESULTS: Of 184 eligible OHCA survivors, 108 were included, with 92 MI controls enrolled. Amongst OHCA survivors, 29% performed z-score ≤ - 1 (at least borderline-mild impairment) in ≥ 2 cognitive domains, 14% performed z-score ≤ - 2 (major impairment) in ≥ 1 cognitive domain while 54% performed without impairment in any domain. Impairment was most pronounced in episodic memory, executive functions, and processing speed. OHCA survivors performed significantly worse than MI controls in episodic memory (mean difference, MD = - 0.37, 95% confidence intervals [- 0.61, - 0.12]), verbal (MD = - 0.34 [- 0.62, - 0.07]), and visual/constructive functions (MD = - 0.26 [- 0.47, - 0.04]) on linear regressions adjusted for educational attainment and sex. When additionally adjusting for anxiety, depression, fatigue, insomnia, hypertension, and diabetes, executive functions (MD = - 0.44 [- 0.82, - 0.06]) were also worse following OHCA. Diabetes, symptoms of anxiety, depression, and fatigue were significantly associated with worse cognitive performance.CONCLUSIONS: In our study population, cognitive impairment was generally mild following OHCA. OHCA survivors performed worse than MI controls in 3 of 6 domains. These results support current guidelines that a post-OHCA follow-up service should screen for cognitive impairment, emotional problems, and fatigue.TRIAL REGISTRATION: ClinicalTrials.gov, NCT03543371. Registered 1 June 2018.
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48. |
- Blennow Nordström, Erik, et al.
(författare)
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Neuropsychological outcome after cardiac arrest : A prospective case control sub-study of the Targeted hypothermia versus targeted normothermia after out-of-hospital cardiac arrest trial (TTM2)
- 2020
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Ingår i: BMC Cardiovascular Disorders. - : Springer Science and Business Media LLC. - 1471-2261. ; 20:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: This study is designed to provide detailed knowledge on cognitive impairment after out-of-hospital cardiac arrest (OHCA) and its relation to associated factors, and to validate the neurocognitive screening of the Targeted Hypothermia versus Targeted Normothermia after Out-of-Hospital Cardiac Arrest trial (TTM2-trial), assessing effectiveness of targeted temperature management after OHCA. Methods: This longitudinal multi-center clinical study is a sub-study of the TTM2-trial, in which a comprehensive neuropsychological examination is performed in addition to the main TTM2-trial neurocognitive screening. Approximately 7 and 24 months after OHCA, survivors at selected study sites are invited to a standardized assessment, including performance-based tests of cognition and questionnaires of emotional problems, fatigue, executive function and insomnia. At 1:1 ratio, a matched control group from a cohort of acute myocardial infarction (MI) patients is recruited to perform the same assessment. We aim to include 100 patients per group. Potential differences between the OHCA patients and the MI controls at 7 and 24 months will be analyzed with a linear regression, using composite z-scores per cognitive domain (verbal, visual/constructive, working memory, episodic memory, processing speed, executive functions) as primary outcome measures. Results from OHCA survivors on the main TTM2-trial neurocognitive screening battery will be compared with neuropsychological test results at 7 months, using sensitivity and specificity analyses. Discussion: In this study we collect detailed information on cognitive impairment after OHCA and compare this to a control group of patients with acute MI. The validation of the TTM2 neurocognitive screening battery could justify its inclusion in routine follow-up. Our results may have a potential to impact on the design of future follow-up strategies and interventions after OHCA. Trial registration: ClinicalTrials.gov, NCT03543371. Registered 1 June 2018
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