[VOTE versus ACLTE: comparison of two snoring noise classifications using machine learning methods]. / VOTE versus ACLTE: Vergleich zweier Schnarchgeräuschklassifikationen mit Methoden des maschinellen Lernens.

BACKGROUND: Acoustic snoring sound analysis is a noninvasive method for diagnosis of the mechanical mechanisms causing snoring that can be performed during natural sleep. The objective of this work is development and evaluation of classification schemes for snoring sounds that can provide meaningful diagnostic support. MATERIALS AND METHODS: Based on two annotated snoring noise databases with different classifications (s-VOTE with four classes versus ACLTE with five classes), identically structured machine classification systems were trained. The feature extractor openSMILE was used in combination with a linear support vector machine for classification. RESULTS: With an unweighted average recall (UAR) of 55.4% for the s­VOTE model and 49.1% for the ACLTE, the results are at a similar level. In both models, the best differentiation is achieved for epiglottic snoring, while velar and oropharyngeal snoring are more often confused. CONCLUSION: Automated acoustic methods can help diagnose sleep-disordered breathing. A reason for the restricted recognition performance is the limited size of the training datasets.

[Acoustic information in snoring noises]. / Akustische Informationen von Schnarchgeräuschen.

BACKGROUND: More than one third of all people snore regularly. Snoring is a common accompaniment of obstructive sleep apnea (OSA) and is often disruptive for the bed partner. OBJECTIVE: This work gives an overview of the history of and state of research on acoustic analysis of snoring for classification of OSA severity, detection of obstructive events, measurement of annoyance, and identification of the sound excitation location. MATERIALS AND METHODS: Based on these objectives, searches were conducted in the literature databases PubMed and IEEE Xplore. Publications dealing with the respective objectives according to title and abstract were selected from the search results. RESULTS: A total of 48 publications concerning the above objectives were considered. The limiting factor of many studies is the small number of subjects upon which the analyses are based. CONCLUSION: Recent research findings show promising results, such that acoustic analysis may find a place in the framework of sleep diagnostics, thus supplementing the recognized standard methods.

Perch-hunting in insectivorous Rhinolophus bats is related to the high energy costs of manoeuvring in flight.

Foraging behaviour of bats is supposedly largely influenced by the high costs of flapping flight. Yet our understanding of flight energetics focuses mostly on continuous horizontal forward flight at intermediate speeds. Many bats, however, perform manoeuvring flights at suboptimal speeds when foraging. For example, members of the genus Rhinolophus hunt insects during short sallying flights from a perch. Such flights include many descents and ascents below minimum power speed and are therefore considered energetically more expensive than flying at intermediate speed. To test this idea, we quantified the energy costs of short manoeuvring flights (<2 min) using the Na-bicarbonate technique in two Rhinolophus species that differ in body mass but have similar wing shapes. First, we hypothesized that, similar to birds, energy costs of short flights should be higher than predicted by an equation derived for bats at intermediate speeds. Second, we predicted that R. mehelyi encounters higher flight costs than R. euryale, because of its higher wing loading. Although wing loading of R. mehelyi was only 20% larger than that of R. euryale, its flight costs (2.61 ± 0.75 W; mean ± 1 SD) exceeded that of R. euryale (1.71 ± 0.37 W) by 50%. Measured flight costs were higher than predicted for R. mehelyi, but not for R. euryale. We conclude that R. mehelyi face elevated energy costs during short manoeuvring flights due to high wing loading and thus may optimize foraging efficiency by energy-conserving perch-hunting.

[Evidence for laser acupuncture in cases of orthopedic diseases : a systematic review]. / Evidenz zur Laserakupunktur bei orthopädischen Erkrankungen : Ein systematisches Review.

BACKGROUND AND OBJECTIVES: The aim of this review is to evaluate the evidence for laser acupuncture in selected orthopaedic diseases. MATERIAL AND METHODS: Randomized controlled studies, meta-analyses and systematic reviews were identified by a systematic search strategy in Medline and the Cochrane library. The studies were evaluated using the quality criteria of the Oxford Centre of Evidence Based Medicine. RESULTS: For the selected orthopedic diseases (medial and lateral epicondylitis, myofascial pain syndrome of the neck, back and shoulder and osteoarthritis), meta-analyses, systematic reviews and eight randomized controlled studies were found. All other published studies used laser therapy without consideration of classical acupuncture points. All studies had significant drawbacks in methodological quality and the number of patients included. In more recent trials, improvement towards higher methodological quality was obvious. Although current evidence is equivocal, positive effects can be assumed in myofascial pain syndromes of the neck, back and shoulder. Laser acupuncture is advantageous in terms of side effects compared to classical acupuncture techniques. CONCLUSION: Better, well designed randomized studies with higher power are mandatory in orthopedic diseases.

Relative absence of psychopathology in benign essential blepharospasm and hemifacial spasm.

We report on the psychopathology and illness-related changes of life in patients with benign essential blepharospasm (BEB) or hemifacial spasm (HFS). Fifty-six patients with BEB and 40 patients with HFS completed the SCL 90R, a screening instrument for psychiatric symptomatology, and the Freiburg Questionnaire for Dystonia (FQD), a questionnaire about psychosocial changes in subjects with movement disorders. In both BEB and HFS patients, the mean scores on all but one subscale of the SCL 90R remained within the double standard deviation of normal. In comparing BEB to HFS patients in illness-related changes of life, BEB patients were more severely disabled in all areas of life examined. Psychological distress in BEB, but not in HFS, correlated with physical disability and in particular with impairment of vision.

Measurement of respiratory mechanics with forced oscillations. Comparison of two methods (Siregnost FD 5 versus a pseudorandom noise technique).

Two methods for measuring respiratory mechanics by forced oscillations were compared, one using a frequency spectrum of 2-32 Hz produced by a pseudorandom noise generator (PRN), the other (Siregnost FD 5) a constant frequency of 10 Hz. In normals and patients with various lung diseases real part of impedance, Re, and phase angle, psi, determined at 10Hz with the two devices correlated well; however, Re measured by Siregnost FD 5 was always higher when compared to PRN. In patients with airway obstruction frequency dependence of resistance and reactance could be shown to be related to the severity of the disease. This important information cannot be obtained by Siregnost FD 5. As Siregnost FD 5 is a simple and reliable method, it is a valuable completion of standard lung function methods. However, for detailed analysis the respiratory system should be investigated at a variety of frequencies.