Evaluation of support in singing.

This study searched for perceptual, acoustic, and physiological correlates of support in singing. Seven trained professional singers (four women and three men) sang repetitions of the syllable [pa:] at varying pitch and sound levels (1) habitually (with support) and (2) simulating singing without support. Estimate of subglottic pressure was obtained from oral pressure during [p]. Vocal fold vibration was registered with dual-channel electroglottography. Acoustic analyses were made on the recorded samples. All samples were also evaluated by the singers and other listeners, who were trained singers, singing students, and voice specialists without singing education (a total of 63 listeners). We rated both the overall voice quality and the amount of support. According to the results, it seemed impossible to observe any auditory differences between supported singing and good singing voice quality. The acoustic and physiological correlates of good voice quality in absolute values seem to be gender and task dependent, whereas the relative optimum seems to be reached at intermediate parameter values.

Genetic basis of climatic adaptation in scots pine by bayesian quantitative trait locus analysis.

We examined the genetic basis of large adaptive differences in timing of bud set and frost hardiness between natural populations of Scots pine. As a mapping population, we considered an "open-pollinated backcross" progeny by collecting seeds of a single F(1) tree (cross between trees from southern and northern Finland) growing in southern Finland. Due to the special features of the design (no marker information available on grandparents or the father), we applied a Bayesian quantitative trait locus (QTL) mapping method developed previously for outcrossed offspring. We found four potential QTL for timing of bud set and seven for frost hardiness. Bayesian analyses detected more QTL than ANOVA for frost hardiness, but the opposite was true for bud set. These QTL included alleles with rather large effects, and additionally smaller QTL were supported. The largest QTL for bud set date accounted for about a fourth of the mean difference between populations. Thus, natural selection during adaptation has resulted in selection of at least some alleles of rather large effect.

The external frame function in the control of pitch, register, and singing mode: radiographic observations of a female singer.

This study investigates pitch control, register, and singing mode related movements of the laryngo-pharyngeal structures by radiographic methods. One trained female singer served as the subject. The results show that singing voice production involves complex movements in the laryngeal structures. Pitch related increase in the thyro-arytenoid distance (vocal fold length) is nonlinear, slowing down as pitch rises. Similar observations have been made earlier. At the highest pitches, a shortening of the distance can be seen, suggesting the use of alternative pitch control mechanisms. The various observations made support the existence of three registers in this trained female singing voice. Open and covered modes of singing seemed to be distinguishable on the basis of different amounts of inner and outer forces acting on the larynx. Therefore, caution must be exercised when generalizing from the results.

Vocal fold strain and vocal pitch in singing: radiographic observations of singers and nonsingers.

The relationship between vocal fold strain and vocal pitch in singers and nonsingers singing a rising pitch series has been indirectly investigated by means of lateral radiographs. Nonsingers tend to exhibit more strain than singers. To standardize the degree of strain, an index of strain per semitone is proposed. The semitone strain indicates the average amount of strain per 1 semitone of pitch increase or decrease. The index has been shown to be affected by several factors: gender, singing training, singing technique, voice class, age, and status of muscle function. Observations suggest that similar groups of individuals occupy different positions on the stress-strain curve, indicated by their semitone strain values.

External laryngeal frame function in voice production revisited: a review.

Research indicates significant contribution of extrinsic laryngeal mechanisms to voice production. This article reviews the major theories of the role of the external laryngeal factors in voice production and relevant experimental data. The review suggests that partly neglected external factors and possibly even misinterpretation of some of the recently documented individual variation in physiological data may have unnecessarily complicated the issues pertaining to the interplay between the physiological mechanisms of the larynx. The implications of contemporary findings and documentation in the modeling of the extrinsic factors are discussed and a synthesis of empirical data into two simple models of the extrinsic forces of pitch control is presented. Also suggested by the review, a basic principle, probably underlying the laryngeal control of phonation, is put forward.

Do molecular markers reflect patterns of differentiation in adaptive traits of conifers?

We have examined patterns of variation of several kinds of molecular markers (isozymes, RFLPs of ribosomal DNA and anonymous low-copy number DNA, RAPDs and microsatellites) and an adaptive trait [date of bud set in Scots pine (Pinus sylvestris L.)]. The study included Finnish Scots pine populations (from latitude 60°N to 70°N) which experience a steep climatic gradient. Common garden experiments show that these populations are adapted to the location of their origin and genetically differentiated in adaptive quantitative traits, e.g. the date of bud set in first-year seedlings. In the northernmost population, bud set took place about 21 days earlier than in the southernmost population. Of the total variation in bud set, 36.4% was found among the populations. All molecular markers showed high levels of within-population variation, while differentiation among populations was low. Among all the studied markers, microsatellites were the most variable (He=0.77). Differences between populations were small, GST was less than 0.02. Our study suggests that molecular markers may be poor predictors of the population differentiation of quantitative traits in Scots pine, as exemplified here by bud-set date.

Rapid diagnosis of adenoviral tonsillitis: a prospective clinical study.

Adenovirus antigen was detected by radioimmunoassay in the nasopharyngeal specimens of 30 of 74 children with febrile exudative tonsillitis. In the other 44 children, the cause of tonsillitis was identified in 16 (beta-hemolytic streptococci or Epstein-Barr, parainfluenza, or herpes simplex viruses). The clinical picture of adenoviral tonsillitis was difficult to differentiate from that of streptococcal disease; 20 of the patients had originally been given antibiotics. In 68% of patients without complications, the serum concentration of C-reactive protein was less than 20 mg/L, suggesting a viral disease. No other hematologic test was found helpful in identifying the adenoviral tonsillitis. The rapid detection of adenovirus antigen permitted withdrawal of unnecessary and ineffective antibiotic treatment in most patients.