Accurate estimation of glottal closing instants (GCIs) and opening instants (GOIs) is important for speech processing applications that benefit from glottal-synchronous processing including pitch ...tracking, prosodic speech modification, speech dereverberation, synthesis and study of pathological voice. We propose the Yet Another GCI/GOI Algorithm (YAGA) to detect GCIs from speech signals by employing multiscale analysis, the group delay function, and N -best dynamic programming. A novel GOI detector based upon the consistency of the candidates' closed quotients relative to the estimated GCIs is also presented. Particular attention is paid to the precise definition of the glottal closed phase, which we define as the analysis interval that produces minimum deviation from an all-pole model of the speech signal with closed-phase linear prediction (LP). A reference algorithm analyzing both electroglottograph (EGG) and speech signals is described for evaluation of the proposed speech-based algorithm. In addition to the development of a GCI/GOI detector, an important outcome of this work is in demonstrating that GOIs derived from the EGG signal are not necessarily well-suited to closed-phase LP analysis. Evaluation of YAGA against the APLAWD and SAM databases show that GCI identification rates of up to 99.3% can be achieved with an accuracy of 0.3 ms and GOI detection can be achieved equally reliably with an accuracy of 0.5 ms.
Only Time Will Tell Naylor, A. Ross
European journal of vascular and endovascular surgery,
October 2018, 2018-Oct, 2018-10-00, 20181001, Letnik:
56, Številka:
4
Journal Article
We present the Dynamic Programming Projected Phase-Slope Algorithm (DYPSA) for automatic estimation of glottal closure instants (GCIs) in voiced speech. Accurate estimation of GCIs is an important ...tool that can be applied to a wide range of speech processing tasks including speech analysis, synthesis and coding. DYPSA is automatic and operates using the speech signal alone without the need for an EGG signal. The algorithm employs the phase-slope function and a novel phase-slope projection technique for estimating GCI candidates from the speech signal. The most likely candidates are then selected using a dynamic programming technique to minimize a cost function that we define. We review and evaluate three existing methods of GCI estimation and compare the new DYPSA algorithm to them. Results are presented for the APLAWD and SAM databases for which 95.7% and 93.1% of GCIs are correctly identified
The renewed strategy towards performing carotid endarterectomy (CEA) within 1–2 weeks of a patient presenting with a TIA or minor stroke is based on a large body of evidence showing that the highest ...risk period for the patient is the first seven days after the index event. Unfortunately, most stroke/vascular services are inadequately resourced to achieve this target and many are more likely to be pre-occupied with treating large numbers of asymptomatic individuals. This paper reviews the evidence underlying the current drive towards expedited intervention in patients presenting with TIA and minor stroke. It will also try to provide reassurance to the surgeon as to how such a strategy can be reconciled with understandable concerns that early CEA in symptomatic patients is associated with poorer perioperative outcomes.
The Na–O2 battery offers an interesting alternative to the Li–O2 battery, which is still the source of a number of unsolved scientific questions. In spite of both being alkali metal–O2 batteries, ...they display significant differences. For instance, Li–O2 batteries form Li2O2 as the discharge product at the cathode, whereas Na–O2 batteries usually form NaO2. A very important question that affects the performance of the Na–O2 cell concerns the key parameters governing the growth mechanism of the large NaO2 cubes formed upon reduction, which are a requirement of viable capacities and high performance. By comparing glyme-ethers of various chain lengths, we show that the choice of solvent has a tremendous effect on the battery performance. In contrast to the Li–O2 system, high solubilities of the NaO2 discharge product do not necessarily lead to increased capacities. Herein we report the profound effect of the Na+ ion solvent shell structure on the NaO2 growth mechanism. Strong solvent–solute interactions in long-chain ethers shift the formation of NaO2 toward a surface process resulting in submicrometric crystallites and very low capacities (ca. 0.2 mAh/cm2 (geom)). In contrast, short chains, which facilitate desolvation and solution-precipitation, promote the formation of large cubic crystals (ca. 10 um), enabling high capacities (ca. 7.5 mAh/cm2 (geom)). This work provides a new way to look at the key role that solvents play in the metal–air system.
The main findings were that the 6-year risk of stroke ipsilateral to a restenosis measuring 50% or greater after carotid endarterectomy (5·8%) was significantly higher than the 1·3% ipsilateral ...stroke rate observed in carotid endarterectomy patients without restenosis (unadjusted hazard ratio HR 5·75, 95% CI 1·80–18·33); p=0·003). By contrast, 40 (1·5%) of 2704 patients with a 0–69% asymptomatic restenosis after carotid endarterectomy had a late ipsilateral stroke (OR 4·77, 95% CI 2·29–9·92).2 The available evidence suggests that there is little benefit in entering carotid artery stenting patients into routine long-term surveillance, because not much benefit would accrue from reintervening. Some patients will, of course, benefit from routine surveillance after carotid endarterectomy or carotid artery stenting (defined in the 2017 European Society for Vascular Surgery Carotid Guidelines4), but the majority of severe asymptomatic restenoses after carotid interventions have a very benign prognosis and can be treated conservatively.
To establish 30 day and mid term outcomes in patients treated for significant stenoses affecting the proximal common carotid artery (CCA) or innominate artery (IA) with/without tandem disease of the ...ipsilateral internal carotid artery (ICA).
Systematic review of early and mid term outcomes in 1 969 patients from 77 studies (1960–2017) who underwent: (i) hybrid open retrograde angioplasty/stenting of the IA/proximal CCA plus carotid endarterectomy (CEA) in patients with tandem disease of the ipsilateral proximal ICA (n = 700); (ii) isolated open surgery to the IA or proximal CCA (no CEA) (n = 686); or (iii) an isolated endovascular approach to IA or proximal CCA stenoses (no CEA) (n = 583).
In the hybrid group with tandem disease (66% involving proximal CCA), the 30 day death/stroke was 3.3%, with a late ipsilateral stroke rate of 3.3% at a median six years follow up. Late re-stenosis was 10.5% for proximal CCA/IA and 4.1% for the ICA. In the isolated open surgery group (78% involving the IA), the 30 day death/stroke was 7%, with a late ipsilateral stroke rate of 1% at a median 12 years follow up. Late re-stenosis within aortic bypasses was 2.6%. In the isolated endovascular group (52% IA, 47% proximal CCA), the majority of procedures were done percutaneously (84%), with a 30 day death/stroke rate of 1.5%. Late ipsilateral stroke was 1% at a median four years follow up, with a re-stenosis rate of 9%.
Procedural risks were higher following isolated open surgical interventions involving the proximal CCA/IA, compared with proximal lesions treated by isolated angioplasty/stenting, or in tandem with CEA. This higher morbidity/mortality may, however, reflect a greater proportion of innominate (vs. proximal CCA) lesions in open surgical series, changes in patient selection, time dependent evolution of medical interventions, and publication bias. The available data were limited and related to very different patient groups and management strategies spanning 57 years. Caution is raised, particularly for open surgery IA and CCA surgery, and for any procedures in asymptomatic patients. In symptomatic patients, the data cautiously support an “endovascular first” strategy for isolated proximal CCA/IA lesions and a hybrid approach for tandem proximal CCA/IA and ICA stenoses.
E-textiles have emerged as a fast-growing area in wearable technology for sports and fitness due to the soft and comfortable nature of textile materials and the capability for smart functionality to ...be integrated into familiar sports clothing. This review paper presents the roles of wearable technologies in sport and fitness in monitoring movement and biosignals used to assess performance, reduce injury risk, and motivate training/exercise. The drivers of research in e-textiles are discussed after reviewing existing non-textile and textile-based commercial wearable products. Different sensing components/materials (e.g., inertial measurement units, electrodes for biosignals, piezoresistive sensors), manufacturing processes, and their applications in sports and fitness published in the literature were reviewed and discussed. Finally, the paper presents the current challenges of e-textiles to achieve practical applications at scale and future perspectives in e-textiles research and development.
A 2011 meta-analysis comparing eversion (eCEA) with conventional (cCEA) carotid endarterectomy in 16,251 patients concluded that eCEA was associated with lower rates of peri-operative stroke and late ...occlusion compared with cCEA. However, randomised controlled trials (RCTs) showed no difference in outcomes. Since then, the literature contains outcome data on 49,500 patients undergoing eCEA or cCEA. An updated meta-analysis was performed to establish whether eCEA confers significant benefit over cCEA.
This was a systematic review of PubMed/Medline, Embase, and Cochrane databases for RCTs and observational studies (OSs) comparing eCEA with cCEA. A sensitivity analysis was also performed using data from OSs with a Newcastle-Ottawa score >5.
There were 25 eligible studies (5 RCTs, 20 OSs) involving 49,500 CEAs (16,249 eCEAs; 33,251 cCEAs). RCT data: Compared with cCEA, eCEA did not confer significant reductions in 30 day stroke, death, death/stroke, death/stroke/MI, or neck haematoma. However, eCEA was associated with reduced late restenosis (OR 0.40; p = .001). OS data: eCEA was associated with significant reductions in 30 day death (OR 0.46; p < .0001), stroke (OR 0.58; p < .0001), death/stroke (OR 0.52; p < .0001), death/stroke/MI (OR 0.50; p < .0001), and late restenosis (OR 0.49; p = .032) compared with cCEA. RCT and OS data combined: eCEA was associated with significant reductions in 30 day death (OR 0.55; p < .0001), stroke (OR 0.63; p = .004), death/stroke (OR 0.58; p < .0001), and late restenosis (OR 0.45; p = .004) compared with cCEA. eCEA vs. patched cCEA (RCT and OS data): There were no differences between the two procedures except for neck haematoma, where eCEA was better than patched cCEA.
Using combined RCT and OS data, eCEA was superior to cCEA regarding peri-operative outcomes (stroke, death, death/stroke) and late restenosis, but was similar to patched CEA in both early and late outcomes. This updated meta-analysis suggests that early and late outcomes following cCEA are similar to eCEA, provided the arteriotomy is patched.
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