bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduced Immunoglobulin M Is Associated with Sinus Mucosal Thickening, Osteitis and Sinus Surgery in Patients with Common Variable Immunodeficiency
Authors: Hagan John B. , Park Miguel A. , Kita Hirohito , Campeau Norbert G.
Published: November 2009

Background: Although common variable immunodeficiency (CVID) is associated with sinopulmonary disease, there are no previous systematic evaluations comparing computed tomographic (CT) sinus imaging with immunoglobulin measurements in patients with this condition. Methods: We performed a retrospective review by a blinded observer using the Lund-Mackay numerical scoring scale as well as a visual scale for remodeling changes in the paranasal sinus bone on CT scans in CVID patients. Results: The sinus CT scans of 19 subjects (9 males, 10 females; median age at diagnosis 34 years) are described. There was an inverse relationship between serum IgM and sinus mucosal thickening as described by the Lund-Mackay scale (R = –0.6398; p = 0.0032). Osteitis of the paranasal sinus bone was almost exclusively found in patients with a reduced serum IgM level of less than 25 mg/dl (p = 0.0074). Conclusion: This is the first study to show that sinus mucosal thickening on CT in patients with CVID is inversely related to serum IgM levels.
Fatal Effects of a Neonatal High-Protein Diet in Low-Birth-Weight Piglets Used as a Model of Intrauterine Growth Restriction
Authors: Jamin Agnès , D’Inca Romain , Le Floc’h Nathalie , Kuster Alice , Orsonneau Jean-Luc , Darmaun Dominique , Boudry Gaëlle , Le Huërou-Luron Isabelle , Sève Bernard , Gras-Le Guen Christèle
Published: November 2009

Background: Although full-term infants suffering intrauterine growth restriction (IUGR) are routinely fed high-protein (HP) formulas to ensure catch-up growth, the effects of HP intake are poorly understood. An IUGR piglet model provides an opportunity to investigate these effects. Methods and Results: Twelve IUGR piglets were artificially fed HP formulas (50% more protein in comparison to sow milk) from the 2nd day of life (d2) until d28. Unexpectedly, all HP piglets developed poor growth, severe hypotonia and polypnea between d10 and d16. One third died spontaneously. This syndrome was investigated to understand its pathophysiology and to adopt a strategy to restore health. Blood and urine biochemistry and amino acid concentrations were investigated in 10 HP piglets and 8 piglets that were fed a normal-protein (NP) formula. In comparison to NP piglets, HP piglets showed significant hypokalemia (2.7 ± 0.6 vs. 3.6 ± 0.6 mmol/l; p < 0.01), hypophosphatemia (1.5 ± 0.2 vs. 3.0 ± 0.3 mmol/l; p > 0.01), hypercalcemia (3.0 ± 0.3 vs. 2.5 ± 0.2 mmol/l; p < 0.01), hyperammonemia (365 ± 4 vs. 242 ± 15 µmol/l; p < 0.05), elevated blood urea (6.5 ± 0.4 vs. 1.3 ± 0.4 mmol/l; p < 0.01) and elevated taurine concentrations (50.2 ± 8.5 vs. 17.7 ± 2.7 µmol/l; p < 0.01). Conclusions: These altered parameters indicated inadequate potassium and phosphorus dietary supplies in HP piglets. When the HP formula was supplemented with monocalcium phosphate and monopotassium phosphate (HP-sup), serum biochemistry was normalized in piglets fed this formula (n = 8). This experimental strategy restored growth in IUGR piglets fed HP-sup, without a toxic effect. The current findings suggest that use of an HP formula without a proportional increase in its phosphorus and potassium content induces pathology similar to the refeeding syndrome in IUGR piglets.
Severe Postnatally Acquired Cytomegalovirus Infection Presenting with Colitis, Pneumonitis and Sepsis-Like Syndrome in an Extremely Low Birthweight Infant
Authors: Fischer C. , Meylan P. , Bickle Graz M. , Gudinchet F. , Vaudaux B. , Berger C. , Roth-Kleiner M.
Published: November 2009

Few cases of severe postnatally acquired cytomegalovirus (CMV) infection are reported in premature infants. We report on an extremely low birthweight (ELBW) preterm infant who presented with a sepsis-like syndrome and multiple organ involvement, notably pneumonitis and colitis. The course of infection was assessed by repeated analysis of urine, tracheal aspirates and blood. The patient was given intravenous ganciclovir. The clinical course was rapidly favorable. Development of neutropenia led to the discontinuation of the antiviral treatment after 28 days. Follow-up showed moderate white matter anomalies on cerebral MRI, a transient hypoacusis and a mild developmental delay at 18 months of corrected age. To the best of our knowledge, this is the first description of a severe combination of pneumonitis and colitis in postnatal CMV infection. Many issues remain controversial and are discussed. We propose that antiviral treatment should be considered in severe postnatal CMV infection in ELBW patients.
Thyroid Eye Disease: Pathogenesis and Treatment
Authors: Sikder Shameema , Weinberg Robert S.
Published: November 2009

Thyroid eye disease is common, yet poorly understood. Clarification of the pathogenesis of thyroid eye disease should provide a rational therapeutic approach. This article provides a review of current pathogenic theories for the condition and of the medical management based on those theories.
Bleb Needling in Encapsulated Filtering Blebs: Evaluation by Optical Coherence Tomography
Authors: Guthoff R. , Guthoff T. , Hensler D. , Grehn F. , Klink T.
Published: November 2009

Purpose: To evaluate the role of anterior segment optical coherence tomography (OCT) in describing the morphology and outcome of encapsulated filtering blebs after bleb needling. Procedures: Prospective assessment of 9 patients – before, 2 days and 6 months after filtering bleb needling with 5-FU – using slit-lamp examination, Goldmann tonometry and OCT. Results: Before the needling, the average internal height of the cyst was 1.3 ± 0.8 mm. Two days after the needling procedure, the cyst collapsed in 5 patients. After 6 months, the average internal cyst height was 0.7 ± 0.4 mm. All patients with a collapsed cyst at day 2 after needling had controlled regulated IOP without glaucoma medication. Conclusions: The preoperative internal height of the cyst does not correlate with the outcome of the needling. A collapsed cyst at day 2 after needling is an indicator of controlled intraocular pressure, whereas a prominent cyst after 6 months indicates poor function.
Autofluorescence Imaging of Cystoid Macular Edema in Diabetic Retinopathy
Authors: Pece Alfredo , Isola Vincenzo , Holz Frank , Milani Paolo , Brancato Rosario
Published: November 2009

Aim: Our purpose was to assess fundus autofluorescence (FAF) images in patients with diabetic retinopathy and cystoid macular edema (CME) and their correlation with fluorescein angiography (FA) and optical coherence tomography (OCT) findings. Methods: Sixty-eight eyes of 34 consecutive patients with diabetic retinopathy were examined with autofluorescence imaging using a confocal scanning laser ophthalmoscope, FA and OCT. The eyes were divided into 2 groups, group 1 with CME and group 2 without. Results: In the 44 eyes of group 1 (65% of the series), we identified 3 patterns of FAF: (1) multicystic increased FA (57%), (2) a single cyst of increased FAF (16%), (3) combined single- and multicystic increased FAF (27%). FA and OCT gave a positive correlation between cystic increased FAF and CME (r = 0.95; p = 0.001). Visual acuity loss was not correlated with the size of the cystic area (p = 0.83), but it was related to significant macular thickening (p = 0.007). Conclusions: Confocal scanning laser ophthalmoscopy can selectively visualize autofluorescent, multilobulated spaces in eyes with diabetic CME. Even if OCT remains preferable for evaluating macular thickening and cysts, FAF might be another useful easy test to rapidly distinguish this entity noninvasively and with no risk.
A Modified Technique for Rectus Muscle Plication in Minimally Invasive Strabismus Surgery
Authors: Mojon Daniel S.
Published: November 2009

Purpose: To present a novel, minimally invasive strabismus surgery (MISS) technique for faster and less invasive rectus muscle plication. Methods: The new plication method is performed without spatula and, therefore, instead of a total dissection (TODI) only a marginal dissection (MADI) of the plicated part of the muscle is performed. Forty patients operated with combined, horizontal MISS rectus muscle recession/MADI plication are retrospectively compared to a similar group of 49 patients, who had MISS recession/TODI plication. The following outcome parameters were analyzed: alignment, binocular single vision, variations in vision, refraction, conjunctival abnormalities, dose-response relationship, and number and types of complications during the first 6 postoperative months. Results: Postoperatively, the conjunctiva over the plicated muscle was less swollen and red with MADI compared to TODI plication (p < 0.01). In esodeviations, there was no significant difference in the dose-response relationship between MADI and TODI plication (1.38 ± 0.44 vs. 1.44 ± 0.50°/mm, p > 0.1). In exodeviations, the difference between MADI and TODI plications was not significant either (1.41 ± 0.38 vs. 1.42 ± 0.50°/mm, p > 0.1). Also final alignment, binocular single vision, visual acuities, refractive changes, or complications did not differ between the two techniques. Conclusions: This study demonstrates that MADI plication is feasible and equally effective in comparison with the TODI plication technique when performing MISS. MADI plication, which is performed without spatula, allows to considerably further reduce postoperative conjunctival swelling and redness.
Downregulation of Serum IGF-1 for Treatment of Early Worsening of Diabetic Retinopathy: A Long-Term Follow-Up of Two Cases
Authors: Chantelau Ernst , Meyer-Schwickerath Rolf , Klabe Karsten
Published: November 2009

In 2003, we reported on 2 cases of nonproliferative and proliferative diabetic retinopathy, subsequent to HbA1c reduction by intensive insulin therapy (so-called early worsening of diabetic retinopathy). This acute condition could partly be reversed by discontinuation of intensive insulin therapy, whereby glycemia increased and serum IGF-1 concentration decreased [Ophthalmologica 2003;217:373–377]. On review 7 years later, both type-2 diabetic patients were on insulin therapy but had failed to achieve good glycemic control. One patient had mild background retinopathy on both eyes, with visual acuity of 1.0 and 0.7 after cataract extraction plus intravitreal triamcinolone injection. The 2nd patient was blind in one eye from secondary glaucoma due to vitrectomy and silicone oil filling; the fellow eye displayed residual retinal neovascularization with a hyaloid membrane and a visual acuity of 0.5. Hence, early worsening as opposed to late worsening of diabetic retinopathy seems to benefit from therapeutic suppression of growth factor action.
Hemodynamic Changes in Maternal Renal Arteries in Twin Pregnancy
Authors: Igarashi Miwa , Miyake Hidehiko , Suzuki Shunji
Published: November 2009

Aim: We examined whether the Doppler waveforms of the maternal renal main arteries are altered in women with twin pregnancy compared with those in singleton pregnancy. Methods: The indices of vascular resistance and acceleration time of the maternal main renal arteries were obtained from 19 healthy women at 37–38 weeks of singleton gestation and 17 women at the same gestational age with nonpreeclamptic twin gestation. Results: There were no significant differences in the indices of vascular resistance between the singleton and twin groups. However, the acceleration time was significantly prolonged in the twin pregnancy group compared with that in the singleton pregnancy group (83.7 ± 24 vs. 59.8 ± 12 ms, p < 0.01). Conclusion: The current results imply that maternal renal arteries are more significantly affected by hemodynamic changes in twin pregnancy than in singleton pregnancy.
TP53 Codon 72 Polymorphism in Classic, Endemic and Epidemic Kaposi’s Sarcoma in African and Caucasian Patients
Authors: Tornesello Maria Lina , Biryahwaho Bennon , Downing Robert , Hatzakis Angelo , Alessi Elvio , Cusini Marco , Ruocco Vincenzo , Katongole-Mbidde Edward , Buonaguro Luigi , Buonaguro Franco M.
Published: November 2009

Objectives: Several studies have examined the association of codon 72 polymorphism of the TP53 gene, encoding either arginine or proline, in several tumor types but none have investigated its role in Kaposi’s sarcoma (KS) development. Methods: In this prevalent case-control study, 67 cutaneous lesions of classic, iatrogenic, endemic as well as epidemic KS from African (n = 22) and Caucasian (n = 45) patients, and blood samples from 150 healthy controls (n = 57 African, n = 93 Caucasian) have been analyzed for arginine and proline allele distribution. Results: Among African cases the proline homozygous, heterozygous and arginine homozygous genotype frequencies were 50.0, 31.8 and 18.2%, respectively, and among controls 54.4, 40.3, and 5.3%, respectively (p = 0.1872). Conversely, among Caucasian cases genotype distributions were 6.7, 55.6, and 37.8%, and among controls 7.5, 34.4, and 58.1%, respectively (p = 0.0567). No significant differences in arginine and proline allele distribution were observed when the cases were stratified by HIV status/tumor type. Conclusions: The results obtained in this study suggest that p53 polymorphism at codon 72 does not represent a risk factor for the development of all forms of KS, either among African or among Caucasian populations.
A Contrastive Investigation of Vowel Duration in German and Dutch
Authors: van Dommelen Wim
Published: November 2009

The point of departure for this investigation were some generally accepted impressionistic statements about durational differences between German and Dutch vowels. Acoustic measurements revealed that differences can best be described with a phonological rule (to be applied in German but not in Dutch) rather than be regarded as inherent. Furthermore it appeared that second-language performance with regard to vowel duration is not necessarily predictable from the duration of pronunciation training.
Statistical Relationships among the First Three Formant Frequencies in Vowel Segments in Continuous Speech
Authors: Sato Shigeru , Yokota Masayuki , Kasuya Hideki
Published: November 2009

Statistical relationships among F1 F2 and F3 in vowel segments in continuous speech were investigated with 909 vowel samples from Japanese sentences uttered by 4 adult male speakers. Determined by minimizing the square errors from the measured F3, two separate planes corresponding to front and back vowels are situated in the F1F2F3 space to obtain the F3 values estimated from F1 and F2. Estimation errors are found to be comparable to difference limens in hearing. Also, uniform/nonuniform formant frequency scaling is discussed in terms of physical differences in the planes for individual speakers.
Articulatory Parameters for the Perception of Bilabials
Authors: Kasuya Hideki , Takeuchi Shoji , Sato Shigeru , Kido Ken’iti
Published: November 2009

In order to investigate articulatory cues for the perception of bilabial consonants, a production model was set up whose control parameters were converted into acoustic parameters by which a terminal analogue speech synthesizer was driven to synthesize test sounds for the perception experiments. Experiments concerning discrimination between /b/ and /w/ and between /m/ and /w/ were then performed with these test sounds. Statistical testing of the results showed that discrimination among the bilabials in an intervocalic context entirely depended on the minimum value of lip opening and that, contrary to the facts hitherto known, it was independent of the rate of lip opening/closure. At the same time, the features [ + anterior, – coronal] and [ + nasal] turned out to be perceptually independent phonological attributes of bilabial and nasal consonants, respectively.
Intelligibilité de la parole bruitée, soumise à une analyse-synthèse par prédiction linéaire
Authors: Garcin Philippe , Sérignat Jean-François
Published: November 2009

Linear prediction analysis-synthesis techniques are commonly implemented in low-bit rate (2,400–9,600 bauds) speech transmission systems. We know that these systems do not work properly if speech is noisy. With the aid of a diagnostic rhyme test in French, we could evaluate the degradation of the intelligibility of synthesized speech. This test was applied to original speech and to linear-prediction synthesized speech, for different signal-to-noise ratios (white noise). The results obtained show clearly that intelligibility is degraded by the linear prediction analysis-svnthesis in a high ambient noise environment.
Segment Duration and the ‘Mora’ in Japanese
Authors: Beckman Mary
Published: November 2009

An experiment was conducted to test two predictions entailed by the hypothesis that Japanese morae have constant durations. The first prediction is that a segment’s duration will conform to its moraic status in an utterance; a consonant will be longer when it is syllabic than when it occurs in a GV mora, and phonemically long consonants will have durations that reflect their moraic structure. The second prediction is that segment lengths will vary to compensate for the intrinsic durations of adjacent segments in order to equalize mora lengths. Neither of these predictions was borne out.
F₀ in the Production of Lenis and Fortis Plosives
Authors: Kohler K.J.
Published: November 2009

The contribution of fundamental frequency (F₀) to the distinction between lenis and fortis plosives is investigated for German in monotone, falling, and rising pitch patterns. A larger F₀ drop is found in the stressed vowel before lenis, as against fortis, in disyllabic words with the contour high + fall. These F₀ differences do not have aerodynamic causes due to articulatory constraints on phonation but can be related to an active laryngeal control in two production patterns differing in overall articulatory effort and also resulting in an articulatory timing contrast. Hypotheses are formulated as regards the importance of this F₀ difference for perception, and with respect to the production and the perception of the lenis/fortis opposition along the F₀ parameter in English.
Algorithms and Devices for Pitch Determination of Speech Signals
Authors: Hess Wolfgang J.
Published: November 2009

In this paper the various pitch determination methods and algorithms (PDAs) are grouped into two major classes: time-domain PDAs and short-term analysis PDAs. The short-term analysis PDAs leave the signal domain by a short-term transformation. They supply a sequence of average pitch estimates from consecutive frames. The individual algorithm is characterized by the short-term transform it applies. The time-domain methods, on the other hand, track the signal period by period. Extraction and isolation of the fundamental harmonic, and investigation of the temporal signal structure are the two extremes between which most of these PDAs are found. After the review of these principles the paper finally discusses different application-oriented aspects, i.e., the role of the PDA in phonetics, education, phoniatrics, and speech communication systems.
Significant Points: Pitch Period Detection as a Problem of Segmentation
Authors: Schäfer-Vincent Kurt
Published: November 2009

In this article the problem of pitch period detection is discussed. The following statements concerning the nature of the problem are made: (1) Pitch period detection is a segmentation problem (in the technical sense of segment). (2) ‘Significant points’ are required as boundary points for the definition of segments. (3) There exists a visual recognition mode for segments in the speech signal. This implies the recognition of ‘significant points’. (4) The visually recognized segments may be related to auditorily recognized segments. Then an algorithm (‘skeletization’) is presented, which selects ‘significant’ points. The ‘significance’ of these points is examined. Characteristic properties of the suggested solution are didscussed.
On the Variabilty in F₀ Patterning and the Function of F₀ Timing in Languages where Pitch Cues Stress
Authors: Thorsen Nina
Published: November 2009

The basic property of pitch as a cue to linguistic stress is fundamental frequency (F₀) change. That leaves room for a lot of variation: in the direction of the change, the amount of change, and its exact coordination with the stressed syllable. Examples (from the literature) from a number of languages and dialects attest that they do indeed exhibit quite striking differences in the stress/F₀ relationship. The decisiveness, under certain circumstances, of the timing of F₀ events is illustrated by the results of a pilot experiment with a disyllabic Danish word: The location of a two-semitone rise from the first to the second syllable – before or after the intervocalic sonorant consonant – will shift listeners’ location of the stress.
Cross-Language Use of Pitch: An Ethological View
Authors: Ohala John J.
Published: November 2009

Certain signaling functions of the pitch of voice are remarkably similar across languages and cultures: (1) high or rising pitch to mark questions, low or falling pitch to mark nonquestions; (2) high pitch to signal politeness, low pitch to signal assertiveness; (3) in ‘sound symbolic’ vocabulary, high tone used with words connoting smallness or diminutive, low tone with words connoting largeness. These patterns can be explained by the assumption that human vocal communication exploits the ‘frequency code’, a cross-species association of high pitch vocalizations with smallness (of the vocalizer), lack of threat, and of low pitch vocalizations with the vocalizer’s largeness and threatening intent.
Prosodic Boundary Signals in German
Authors: Kohler K.J.
Published: November 2009

The investigations reported on in this paper took their departure from earlier findings which showed rhythmic as well as word boundary effects on segment and syllable durations in German, with different strengths in different speakers. They also pointed to influences from F₀ contours and from coarticulation on this timing adjustment. This article is thus concerned with the interplay of rhythmic and semantic structuring of German speech, signalled by prosodic features, especially by F₀ and duration, marginally also by speech pauses. The rhythmic principle is the segment and syllable compression within the foot basic to stress-timing, modified by various coarticulatory processes, which allow faster executions of speech gestures. The semantic principle is that of information structuring, by organizing speech into information units, at a hierarchy of levels, by marking information points within them, and by establishing various degrees of cohesion within and between these information units.
Click Placement and Units of Perceptual Processing
Authors: Barry William J.
Published: November 2009

The relationship between experimental method and the perception hypothesis being examined is a particularly critical one. Here, earlier studies employing the click-placement method are surveyed, and the conclusions drawn there about the perceptual processes involved are discussed. A working hypothesis is developed which enables an examination, for the first time, of Ladefoged and Broadbent’s [1960] original claim concerning basic processing units. Within a hypothetical framework of hierarchically organized perceptual decisions, the click-placement task is applied in a series of experiments designed to approach the question of processing units at segment, syllable and foot level. Evidence is found for the psychological reality of the syllable and foot. The phonetic basis of the foot is examined and found to be replaceable by top-down information. Between foot and syllable level, indications of differential word demarcation were found, dependent on differences in segmental structure.
Indices naturels et indices artificiels en parole de synthèse
Authors: Chafcouloff M.N.
Published: November 2009

An experiment was conducted to test the perceptual relevance of the cues used by Delattre for the synthesis of sonorants in French. For this purpose, stimuli with /j, w, 1, r/ in intervocalic position and in a symmetrical context /i, a, u/ were generated on a formant serial synthesizer. The results derived from identification and preference tests show that minor spectral and temporal modifications improve the auditory quality of the glides /j, w/. In contrast, Delattre’s rules do not lead to a satisfactory synthesis of /1, r/, and important parametric changes concerning acoustic targets, steady-state and transition durations, and overall amplitude should be considered.
F₀ Timing in Danish Word Perception
Authors: Thorsen Nina
Published: November 2009

(1) When vowel and consonant duration cues are ambiguous between /ku·lÓ™/ and /kulÓ™/ an early F₀ rise, relative to the vowel-consonant boundary, will tend to favor identification of stimuli as /ku lÓ™/, while a later F₀ rise increases the number of /kulÓ™/ judgments somewhat. (2) When vowel duration cues are ambiguous between /’bilisd/ and /bi’lisd/ an F₀ rise before the intervocalic consonant will significantly increase the number of/’bilisd/ identifications, whereas an F₀ rise after the consonant yields more judgments of /’bilisd/. The latter result corroborates the acoustic observation that initial voiced consonants in stressed syllables dissociate tonally from the vowel and join up with the preceding material, if any, to the effect that tonally the stress seems to begin with the vowel.
Untersuchungen zur spezifischen Dauer deutscher Vokale
Authors: Antoniadis Zissis , Strube Hans Werner
Published: November 2009

This paper examines the effects of vowel quality (formant frequencies), speaker and place of articulation of the surrounding consonants (/p/, /t/ or /k/) upon the duration of German vowels embedded in a fixed carrier sentence. The results obtained verify and complement known data from other investigations and make it possible to specify formulae, which can be used both in prosodic analysis and in automatic speech synthesis.
Timing Constraints and Coarticulation: Alveolo-Palatals and Sequences of Alveolar + [j] in Catalan
Authors: Recasens Daniel
Published: November 2009

General articulatory characteristics and V-to-C coarticulatory effects for alve-olo-palatals [É], [λ] versus sequences [nj], [lj] in Catalan VCV utterances have been measured at the point of maximum alveolar contact and over time by means of dynamic palatography. Data show that the amount of V-to-C coarticulation in tongue dorsum contact varies inversely with the duration of the temporal lag between the periods of alveolar closure and palatal closure. Results support the view that coarticulation is affected by contrasting timing constraints on articulatory activity.
Vowel Variation in Japanese
Authors: Keating Patricia A. , Huffman Marie K.
Published: November 2009

A language’s use of the phonetic vowel space depends not only on how many vowel phonemes the language has, but on how each phoneme varies allophonically across contexts. This study tests the hypothesis that Japanese vowel allophones, measured from a wide range of contexts, will not fill the vowel formant space. This was predicted because Japanese has few vowel phonemes, distributed unevenly in the vowel space, and has no obvious processes of vowel reduction. Formant frequencies of vowel tokens from word lists and from read texts were compared for 7 speakers. These data show that, in Japanese, vowel allophones in prose fill in the vowel formant space more than allophones in word lists do, mainly as a result of centralization of the prose tokens. The use of the total formant space is determined in part by the distribution of phonemes, and in part by allophone centralization.
Phonological Variability in Mother-Child Speech
Authors: Stoel-Gammon Carol
Published: November 2009

Previous research has provided conflicting findings regarding the phonological characteristics of adult-child speech, with some studies reporting more phonetic clarification and others greater unintelligibility. The present study examined the speech of 10 mothers to their young children (age 15–18 months) and found that a variety of speech styles was used, ranging along a continuum from slow, carefully articulated speech to rapid, casual speech. Each style was associated with particular linguistic and situational contexts. Phonological characteristics of the two styles are described and hypotheses regarding the effect of the observed variability on language acquisition are discussed.
Study of Subglottal Air Pressure during Hindi Stop Consonants
Authors: Dixit R. Prakash , Shipp Thomas
Published: November 2009

This study examines subglottal air pressure (Ps) variations in Hindi stop consonants. The stops were produced in initial, medial and final positions and under different stress conditions in nonsense utterances of the type CV, VCV and VC which were embedded in a frame sentence. The results show no systematic correlation between Ps variations during the oral closure of the stops and the voicing and/or aspiration contrasts associated with them. However, aspiration and a momentary drop in Ps immediately after the release of aspirated stops seem to be systematically related. A systematic relationship between a momentary increase in Ps and production of stress is also observed. The variations in Ps associated with the production of stop consonants appear to be reflections of the changes in the glottal and supraglottal impedances. Ps variations related to normal stress appear to be controlled by the phonatory system rather than the respiratory system. On the other hand, for the implementation of heavy or emphatic stress, the phonatory and the respiratory systems appear to function synergistically.
On Aspiration in Swahili: Hypotheses, Field Observations, and an Instrumental Analysis
Authors: Engstrand Olle , Lodhi Abdulaziz Y.
Published: November 2009

Quantitative evidence to substantiate accounts of Swahili phonetics is scarce. In this paper, attention is drawn to the particularly complex feature of aspiration. A set of working hypotheses for experimental research are formulated. On the basis of field observations, aspiration is assumed to be operative at several levels of Swahili grammar. Contrary claims are reviewed and discussed in relation to informant selection and control methods for experimental procedures. A digital phonetic data base under current construction is outlined. Speech samples from the data base are used to quantify Swahili aspiration along the voice onset time dimension. The data suggest that the physical manifestation of the aspiration feature is relatively strong in Swahili as compared with Swedish.
Perceptual Compensation for Segmentally Conditioned Fundamental Frequency Perturbation
Authors: Reinholt Petersen Niels
Published: November 2009

The paper deals with the role of two types of segmentally conditioned fundamental frequency (F₀) perturbation in speech perception, i. e. the differences in F₀ between high and low vowels and the effect of prevocalic obstruent voicing on F₀. The literature relevant to this issue is reviewed, and the results of a supplementary experiment on F₀ as a cue to vowel identity are reported. On this basis three major points are made: (1) Although the pitch of vowels is influenced psychoacoustically by their spectral shape, this effect is too small to be of any significant importance in speech perception. (2) The two types of F₀ perturbation are not treated differently in the speech perception process, and (3) irrespective of type, the segmentally conditioned F₀ variation can function as a cue both to segment identity and to the identity of prosodic categories, depending on the actual demands upon the speech perception system.
Prosodic Effects on Lenis/Fortis Perception: Preplosive F₀ and LPC Synthesis
Authors: Kohler Klaus J. , van Dommelen Willem A.
Published: November 2009

Two experiments, each with three sub-tests, examine the influences on lenis/ fortis perception of both preplosive F₀ (flat vs. rising) in monotone utterance intonation and of natural vs. synthetic speech quality. The German word ‘leiten’ [laetn], ‘to lead’, pronounced by a male and a female speaker [Experiments I and II, respectively), formed the basis for the test stimulus construction. The stop closure (= silence) was varied by the same 5 steps to yield a continuum from clear /t/ to clear /d/ in all tests. The data support the conclusion that a rising as opposed to a non-rising F₀ at the end of a preplosive vowel in a monotone utterance intonation increases /t/ perception. They also show that LPC synthesis quality is a strong additional cue for /t/, being stronger where it characterizes the whole utterance rather than only a small part of it. These influences on lenis/fortis perception are found to be consistent for the male and the female voice.
Speaking Rate and Segments: A Look at the Relation between Speech Production and Speech Perception for the Voicing Contrast
Authors: Miller J.L. , Green K.P. , Reeves A.
Published: November 2009

When listeners process segmentally relevant properties of the speech signal they do so in a rate-dependent manner. This is seen as a shift in the perceptual category boundary; as rate declines and overall syllable duration increases, the category boundary moves toward a longer value of the acoustic property in question. Focusing on the /b/-/p/ distinction specified by voice onset time (VOT), we investigated whether the acoustic modifications that occur with an alteration in speaking rate accord with this pattern of perceptual boundary shift. Two main findings emerged. First, as speaking rate became slower and overall syllable duration became longer, the VOT value of the consonant, especially that of the voiceless /p/, also became longer. Second, and most important, the VOT value that optimally separated the /b/ and /p/ VOT distributions also changed with rate, increasing with increasing syllable duration. However, the magnitude of the boundary shift obtained for these production data was greater than that typically found in perceptual experiments. This suggests the existence of constraints on the extent to which the perceptual system can accommodate for alterations due to rate of speech.
The Monophonematic Status of Diphthongs Revisited
Authors: Berg Thomas
Published: November 2009

This paper presents a challenge to the well-established monophonematic view of German and English diphthongs. Empirical evidence is provided by speech error patterns showing that misordered diphthongs occasionally split apart during the error process. Since both splitting up and remaining intact can be observed with diphthongs, a linear analysis, which predicts an all-or-none behaviour, proves to be inadequate. An explanation for the relative cohesiveness of these phonemes can be found in a multilevel representation within which diphthongs are two discrete atoms on the segmental level which are molecularized in the suprasegmental structure.
Discrimination of Five Voice Qualities and Prediction to Perceptual Ratings
Authors: Pittam Jeffery
Published: November 2009

A series of acoustic measures based on the long-term average spectrum were developed to discriminate five voice qualities. These were breathy voice, creaky voice, nasal voice, tense voice and whispery voice. A preliminary study first tested the effectiveness of a series of ‘equal-Hertz’ intervals in terms of their ability to discriminate the five voice types. The best of these was then compared to Bark and Mel intervals, using discriminant analysis. The most effective discriminators were shown to be the 1.5-Bark and 200-Mel intervals. The significant discriminators in all the discriminant analyses were then used to predict expert perceptual ratings of the voice qualities. All measures developed successfully predicted to all the voice types except nasal voice.
From Sagittal Distance to Area
Authors: Sundberg J. , Johansson C. , Wilbrand H. , Ytterbergh Christer
Published: November 2009

In speech articulation studies, data on the pharynx are scarce. Still, the pharynx is an important part of the vocal tract. The present paper reports on an attempt to use computed tomography for investigating the pharynx. Axial computed tomograms were taken at four levels in the pharynx of a male and a female subject sustaining the vowels [u:, i:, α:, œ:]. From the tomograms the lateral width and the cross-sectional area were measured and their relations to the sagittal distance from the back pharynx wall to the midline of the tongue examined and compared with previously published data. In addition, some previous results derived from plaster casts are presented showing the corresponding distance-to-area relationship in the mouth region of some male and female subjects.
Contextual Neutralization of Vowel Length: Evidence from Dutch
Authors: Lahiri Aditi , Schriefers Herbert , Kuijpers Cecile
Published: November 2009

Based on recent experimental studies of word-final devoicing in languages like German and Catalan which show production differences between the neutralized and nonneutralized consonants, it has been claimed that phonological neutralization is ‘incomplete’. It seems, however, that this claim is quite premature given that most studies have considered only the neutralizing phenomenon of word-final devoicing. In this paper, we examine a qualitatively different neutralizing phenomenon – the neutralization of vowel length in open syllables. We compared the duration of Dutch long vowels which are derived by an open-syllable lenghtening rule to those that are underlyingly long (cf. [da:len] < /dal+en/ vs. [ba:len] < /ba:l+en/). Our study shows that there is no difference in the duration between these vowels and that, at least, in this instance, contextual neutralization does lead to identical surface realization of distinct phonological segments.
Two Magnetic Methods for Articulatory Measurements
Authors: Panagos Georgios , Strube Hans Werner
Published: November 2009

We present two magnetic methods for measuring articulatory activities. Unlike previous methods, the magnetic fields are uniform. Three alternating magnetic fields induce voltages in two detectors, a magnetic potentiometer and a flat coil. Thus we are able to measure jaw and tongue movements during speech production. These methods are biologically safe. The miniaturized detectors do not disturb the speech movements. Some preliminary results are presented. These methods can also be applied for other kinds of vectorial distance measurement.
Influences of Contextual and Local Temporal Information on Perception of a Stop Consonant after [s]
Authors: Bailey Peter J.
Published: November 2009

Much of the perceptual information for a stop consonant in an [s]-stop cluster inheres in temporal properties of the acoustic signal local to the period of low energy corresponding to stop closure. However, stop percepts in this context are also influenced by the rate of speech in a precursor phrase to which the cluster is appended. The two experiments in this paper attempt to explore the dissociability of these local and longer-term perceptual influences, and to investigate the interactions between them. The results of the experiments reveal a complex pattern of interactions which suggests that a simple distinction between segmental and suprasegmental temporal information for phonetic contrasts is unrealistic.
Labial Articulation Patterns Associated with Segmental Features and Syllable Structure in English
Authors: Macchi Marian
Published: November 2009

The purpose of the work described here was to relate different types of phonological categories – like phonemic distinctive features and syllable boundaries – with articulatory parameters for lip and jaw height. The analysis is based on data for 2 talkers of American English, using the University of Tokyo X-ray microbeam system. We studied the articulatory realization of linguistic contrasts in syllable boundary location for the intervocalic labial stop consonant /p/ and the articulatory realization of intervocalic /p/ in the environment of phonemically different vowels. The /p/s in contrasts associated with the phonemic vowel environment (e. g., /p/ in /ipi/ versus /apa/) were realized in articulation by a constant lip pellet position, implemented by an inverse relation between jaw height and lip articulator height. The syllable structure contrasts (e. g., syllable-initial /p/ versus syllable-final /p/) were realized by jaw height differences, without any lip articulator difference. These results can be accounted for by describing the observable lip pellet position for /p/ as a function of two independent variables: a constant lip pellet goal, at the level of segmental vowel environment, plus a jaw height for a particular syllable structure.
Dynamic Information in the Identification and Discrimination of Vowels
Authors: Fox Robert Allen
Published: November 2009

The dynamic theory of vowel perception emphasizes the importance of the consonant transitions in CVC syllables to the identification of the vowel itself. However, the dynamic theory is relatively vague in terms of what perceptual processes may be involved and it says nothing about the role of auditory and/or phonetic memory for such ‘dynamic events’. The present study created three synthetic [É­]-[ε] continua consisting of a [b Vb] full-syllable continuum, a silent-center continuum (which had over 72% of the medial vowel replaced by silence) and an isolated vowel continuum to specifically examine (1) the use of auditory and phonetic memory for dynamic acoustic cues and (2) the ability of listeners to track the trajectories of very brief formant transitions. Experiment 1 demonstrated that there were no significant differences among the three continua in terms of listener identifications but that the silent-center tokens demonstrated significantly lower within-category discriminations, perhaps because of degraded auditory representation. Experiment 2 required listeners to make cross-continuum vowel discriminations and showed that some degree of acoustic similarity was important – listeners were particularly poor at discriminating between the silent-center and vowel-only tokens. This suggests that listeners were not able to make discriminations on the basis of abstract vowel labels alone. Experiment 3 demonstrated that listeners could make quite accurate vowel identifications even when as little as 1 pitch period of acoustic energy signaled the consonant transitions in the silent-center tokens. Experiment 4 showed that listeners’ identifications of the silent-center stimuli were based on the formant changes in the transitions rather than their endpoint frequencies.
Perception and Production of English Vowels by German Learners: Instrumental-Phonetic Support in Language Teaching
Authors: Barry William J.
Published: November 2009

Results are presented from two experiments which examine the application of instrumental phonetic methods to the needs of the teacher of a foreign language. First, the use of a traditional psychophonetic test procedure as a diagnostic tool is demonstrated. Second, the effect of reading, imitation, and prompted recall on production is examined, and the implications for teaching and pronunciation monitoring discussed.
Naive Subjects’ Assignments of Stress Ranks
Authors: Slootweg A.M. , Rietveld A.C.M.
Published: November 2009

In three experiments, it is investigated to what extent naive listeners agree in ranking the stress of syllables in Dutch words. Four factors influencing the scores are isolated: the position of the primary stress, the awareness of rhythmic patterns, a tendency to assign prominence to the initial syllable and a segmental factor which disallows prominence on syllables with schwa. As these factors oppose or strengthen each other, they explain fluctuations in the subjects’ agreement.
The Influence of Pre- and Postplosive Fundamental Frequency on /t/–/d/ Perception in German
Authors: van Dommelen Wim A.
Published: November 2009

This paper is concerned with the dependence of segment perception on microprosodic perturbations of a macroprosodic intonation contour. The test paradigm involves tokens of the German word pair ‘leiten’/’leiden’, where the vowel and closure durations are simultaneously manipulated. A falling versus a flattish fundamental frequency contour during the diphthong is shown to bias phoneme judgements towards lenis. As regards variation of F₀ in the syllabic nasal (falling vs. flattish vs. rising) both falling and rising contours cause an increase in fortis judgements. Furthermore, variations of F₀ in the vowel and in the nasal do not interact. In view of the necessity to use LPC synthetic speech as a tool in F₀ manipulation, the potential artefact of LPC synthesis in these experiments on F₀-conditioned segment perception is also investigated. The use of a synthetic instead of a natural vowel quality shifts the phoneme boundary towards more lenis, though this effect is weak.
Effect of Speaking Rate on the Perception of Vowels
Authors: Gottfried Terry L. , Miller Joanne L. , Payton Paula E.
Published: November 2009

Three experiments examined the conditions under which the speaking rate of a context sentence affects vowel identification. In these experiments, listeners identified the vowel in synthetic /b/-vowel-/t/ syllables that varied systematically in the duration (temporal), the formant frequencies (spectral), or both the duration and formant frequencies (temporal-spectral) of the steady-state portion of the syllable. These syllables were embedded in two synthetic sentence frames, one with the temporal characteristics of a natural fast sentence and one with those of a slow sentence. For two vowel distinctions that are specified in natural speech by both temporal and spectral characteristics, /I/-/i/ and /ε/-/æ/, listeners adjusted their identification of the vowels according to the sentence rate in all three conditions. Although there was a trend for the rate effect to be reduced in the temporal-spectral condition, the influence of sentential rate was never eliminated. By contrast, for a vowel distinction that is naturally specified primarily by spectral characteristics, /ε/-/ι/, there was no effect of sentence rate in any of the conditions. We conclude that when vowels are differentiated in natural speech by both temporal and spectral information, listeners obligatorily use the duration of the vowel to identify it and do so in relation to the rate of the sentence in which the vowel occurs.
Perception of ‘Voicing’ in Whispered Stops
Authors: Munro Murray J.
Published: November 2009

Amplitude measurements of 32 whispered tokens of /p/ and /b/ produced in four vowel contexts revealed that whispered /b/ tended to have a steeper rise slope relative to the following vowel than did /p/. In a perceptual experiment, short (60-ms) whispered stop + vowel utterances were played to 8 listeners. Their identification scores were significantly above chance, but lower than what might be expected for stop + vowel stimuli produced with normal voicing. The pattern of identifications showed no relationship to the measured rise time differences.