bluuebunny/crossref_metadata_2025 huggingface dataset:
An Articulatory Study of Consonant-Induced Vowel Duration Changes in English
Authors: de Jong Kenneth
Published: November 2009

The effects of voicing, manner, and number of consonants on the duration of previous vowels in English can be created in three ways: by planned expansion or contraction of the entire vowel, by changing the relative timing of consonant and vowel gestures, or by modifying the duration of the closing movement for the consonants. An X-ray micro-beam data base of 2 speakers of American English reciting monosyllabic words, which differed in their final consonants and in their position in the accentual structure of the utterance, was studied to evaluate these three accounts. In this data base, vowel duration differences due to the voicing of the following consonants were amplified by the presence of accent. Also, many of the duration differences associated with the following consonants are localized in the later portion of the opening movement, suggesting that subjects often create vowel duration changes by initiating the consonant closing gesture at an earlier or later time relative to the opening gesture.
The Representation of Stop Consonants in Three-Dimensional Acoustic Space
Authors: Sussman Harvey M.
Published: November 2009

An acoustic study of English initial voiced stops showed that the three place categories are well distinguished on the basis of three properties: second-formant onset frequency (F2 onset), second-formant frequency of the vowel nucleus (F2), and third-formant onset frequency (F3 onset). Ten male and 10 female subjects produced multiple tokens of /bVt/, /dVt/, and /gVt/ with ten different medial vowels. Three-dimensional scatterplots were generated using the above acoustic properties as coordinates. Three nonoverlapping clusters corresponding to the three place categories were evident across all subjects. Discriminant analyses based on F2 onset, F2 vowel, and F3 onset as predictor variables showed a mean correct categorization rate of 84.5% when tested within gender groups. The graphic and statistical results are interpreted as indicating that phonetic categories may be defined and represented in purely acoustic terms if variably valued multiple acoustic properties are relationally examined.
Integrating Articulations in the Perception of Vowel Height
Authors: Kingston John
Published: November 2009

In vowels contrasting for height, a large number of articulations covary with tongue height, which is supposed to be the principal bearer of the contrast. However, attempts to link these covarying articulations to tongue movement physiologically have been largely unsuccessful, and the particular pattern of covariation appears to make more sense as a concerted effort to influence the perceived height of F1. The experiments reported here used the Garner interference paradigm, modified to assess the perceptual primacy of stimulus dimensions, to show that the acoustic effects of two of these covarying articulations, velum height (nasalization) and rate of vocal fold vibration (pitch) are integrated perceptually with the acoustic effects of varying tongue height. This perceptual integration suggests that the different articulations are not independently perceived, contrary to the predictions of direct realist theories of speech perception, that articulatory events covary so as to enhance each other’s perceptual effects, and that the surface phonological or initial phonetic representation of vowels might be quite richly specified (contrary to claims of phonetic underspecification).
The Phonetics/Phonology Issue in the Study of Articulatory Reduction
Authors: Kohler K.J.
Published: November 2009

After a brief review of important landmarks in the development of the phonetics/phonology dichotomy, the need for the integration of the two approaches is stressed. It is argued that, on the one hand, instrumental speech signal processing has to be subordinated to the language point of view, but that, on the other hand, the linguistic categories, such as phoneme and distinctive feature, should be critically assessed in respect of their adequacy as language categories, relevant for speakers and hearers. The phoneme is associated with word phonology, and problems are pointed out that arise when it is applied to the phonetics above the word. With reference to articulatory reduction processes in German, especially in function words, the interplay between the principles of economy of effort, on the part of the speaker, and of the need for distinctiveness for the listener are discussed. Empirical data are presented showing that reductions can be arranged along a continuous scale in spite of phonemic switches, if the physiological and articulatory dynamics are taken into account, providing deeper insight into human speech and language than the phonemic perspective. The concept of a ‘reduction coefficient’ is introduced and the call for a new ‘paradigm’ in the science of the spoken medium put forward.
Nasal Epenthesis in Hindi
Authors: Ohala Manjari , Ohala John J.
Published: November 2009

Modern Hindi words such as [dãt] ‘tooth’ and [t ∫ãnd] ‘moon’ had similar phonetic structure in Middle Indo-Aryan, with conventional transliterations of danta and čanda, respectively. The development of the long nasal vowel is usually correlated with loss of the nasal consonant. If so, why does one form still contain a nasal consonant? We argue that a sequence of nasalized vowel + voiced stop (but not voiceless stop) can, for phonetic reasons, engender an epenthetic nasal, and we demonstrate that the same process can be found (nondistinctively) in present-day Hindi and French in the junction between a word-final nasal vowel and a following word-initital voiced stop. A nondistinctive epenthetic nasal can become a ‘full’ or ‘lexical’ nasal when listeners reinterpret this transitional event as purposeful or intended.
Stops in the World’s Languages
Authors: Henton Caroline , Ladefoged Peter , Maddieson Ian
Published: November 2009

This account of the great variety of stops in the world’s languages shows that, apart from their place of articulation, these sounds can be described principally in terms of the activities that occur at three phases: onset, closure, and release. Other potentially contrastive features discussed include length, and the use of the glottalic airstream mechanism (other airstream mechanisms are not considered here). Phonologically only two phases – closure and release – are exploited; independent distinctions of features such as phonation type or articulatory manner cannot be found in the onset phase. We examine the combinatorial possibilities of the features that are used and discuss implications for phonological feature systems.
Intonation: A Distinctive Parameter in Grammatical Constructions
Authors: Välimaa-Blum Riitta
Published: November 2009

If intonation and syntactic form are independent of each other, as it is generally assumed, then we would expect that a particular sentence pattern would be assigned any number of distinct tunes on separate readings. An experiment with subjects reading aloud contextualized sentences in Finnish revealed, however, strong default relations between syntax and intonation. Another common assumption is that F₀ height is a metalinguistic variable that does not express linguistic contrasts but only various degrees of emphasis. The results here indicate that neutral declarative contours are statistically significantly different from qualitatively identical tunes with a final focus and these statistical differences coincide with semantic differences in the sentences. The conclusion is that grammatical constructions, as fundamental linguistic categories, may count intonation as one of their formal parameters.
Intonation of Clause-Internal Filled Pauses
Authors: Shriberg Elizabeth E. , Lickley Robin J.
Published: November 2009

Clause-internal filled pauses and preceding peak fundamental frequency (F₀) values were analyzed to determine whether the intonation of filled pauses is relative to, or independent of, prior prosodic context. Higher peaks were found to be systematically associated with higher filled-pause values, supporting the ‘relative’ hypothesis. A linear model, in which filled-pause F₀ was expressed as an invariant (over speakers) proportion of the distance between preceding peak F₀ and a speaker-dependent baseline F₀, produced results nearly identical to those of a two-parameter model in which the coefficients of peak and baseline were allowed to vary freely. The model was less appropriate for filled pauses after sentence-initial peaks, but unaffected by temporal variables.
The Use of Prosody in Disambiguation in Mandarin
Authors: Shen Xiaonan Susan
Published: November 2009

This article examined the clarification of surface structure ambiguity via prosody in Mandarin. An acoustical analysis and a perceptual study were carried out for this purpose: the acoustical analysis was aimed at identifying the prosodic cues for disambiguation, and the perceptual study explored how syntactical structure was recovered via prosody. The acoustical analysis of syntactically ambiguous pairs resulting from different bracketings revealed that prosodic disambiguation consisted of pause insertion, F₀ lowering, intensity reduction, and preboundary lengthening. Moreover, laryngealization frequently was observed at syntactic breaks. The perceptual study of ambiguous pairs of edited speech tokens indicated that (1) pause was a more powerful cue than preboundary lengthening in syntactical recovery, and (2) only a large amount of preboundary lengthening led to successful parsing of ambiguous sentences.
From EMG to Formant Patterns of Vowels: The Implication of Vowel Spaces
Authors: Maeda Shinji , Honda Kiyoshi
Published: November 2009

With a few exceptions, EMG data are interpreted with reference to the intended output, such as the phonetic description of utterances spoken by speakers. For a more rigorous interpretation, the data should also be analysed in terms of the displacement of the articulators and the acoustic patterns. In this paper, we describe our attempts to calculate the formant patterns from EMG activity patterns via an articulatory model. The value of the model parameters, such as the tongue body position or tongue body shape, is derived from the EMG activities of the specific pairs of antagonistic tongue muscles. The model-calculated F1-F2 patterns for 11 American English vowels correspond rather well with those measured from the acoustic signals. What strikes us is the simplicity of the mappings from the muscle activities to vocal-tract configurations and to the formant patterns. We speculate that the brain optimally exploits the morphology of the vocal tract and the kinematic functions of the tongue muscles so that the mappings from the muscle activities (production) to the acoustic patterns (perception) are simple and robust.
Tongue Body Kinematics in Velar Stop Production: Influences of Consonant Voicing and Vowel Context
Authors: Löfqvist Anders , Gracco Vincent L.
Published: November 2009

This study examines vertical and horizontal tongue body movements in VCV sequences, where the consonant is a voiced or voiceless velar stop. The movement data were recorded using a magnetic transduction technique in two subjects. Consistent with studies of lip and jaw kinematics, the duration of the tongue body raising movement towards closure for the consonant was longer for the voiced stop. In contrast to lip and jaw movements, peak velocity and amplitude of the raising movements were consistently higher for the voiced stop. The larger displacement of the closing movement for the voiced stop was due to a lower starting position of the movement during the preceding vowel. Examination of the tongue body lowering movement for the vowel preceding the velar stop showed it to be longer when the following stop was voiced. Also this lowering movement had a higher peak velocity and amplitude in the voiced environment. These results thus suggest that both the lowering and raising movements in the VC sequence are affected by the voicing status of the consonant. In addition, the second vowel in the VCV sequence showed reliable influences on tongue body movements for the first vowel and the consonant.
Evidence for the Adaptive Nature of Speech on the Phrase Level and Below
Authors: Nooteboom Sieb G. , Eefting Wieke
Published: November 2009

This paper reports some production and perception experiments challenging the idea that the rate of articulation of interpause intervals of speech is solely conditioned by internal phonological factors. The results reported demonstrate that, at least for one professional newsreader, rate of articulation in interpause intervals is conditioned by context and that deviations from the intended rate are easily noticeable and affect perceived naturalness negatively. It is also demonstrated that a context-conditioned rate of articulation does not affect interpause intervals uniformly but is unevenly distributed. These results are interpreted in terms of speaker adaptation to the listener’s running access to signal-independent information.
Some Distributional Facts about Fricatives and a Perceptual Explanation
Authors: Balise Raymond R. , Diehl Randy L.
Published: November 2009

Across and within languages voiced sibilants tend to be disfavored relative to voiceless ones. This paper explores the claim that voicing more adversely affects the distinctive acoustic properties of sibilants than those of nonsibilants. One prediction associated with this claim is that voicing differentially lowers the amplitude of frication noise for sibilants and non-sibiliants so that amplitude differences between the two classes are reduced. Acoustic measurements confirm this prediction. A second prediction is that voicing has a greater negative effect on the identification of sibilants than nonsibilants. Perceptual results from this and previous studies are somewhat variable, but averaged data support this prediction. The findings suggest that voiced sibilants are disfavored in part for perceptual reasons.
Conventional, Biological and Environmental Factors in Speech Communication: A Modulation Theory
Authors: Traunmüller Hartmut
Published: November 2009

Speech signals contain various types of information that can be grouped under the headings phonetic, affective, personal and transmittal. Listeners are capable of distinguishing these. Previous theories of speech perception have not considered this fully. They have mainly been concerned with problems relating exclusively to phonetic quality. The theory presented in this paper considers speech signals as the result of allowing conventional gestures to modulate a carrier signal that has the personal characteristics of the speaker, which implies that in general the conventional information can only be retrieved by demodulation.
The Influence of Language on the Acoustic Properties of Phonetic Features: A Study of the Feature [strident] in Ewe and English
Authors: Utman Jennifer Aydelott , Blumstein Sheila E.
Published: November 2009

This study explored the extent to which the acoustic manifestation of a phonetic feature is influenced by the linguistic role that the feature plays in the sound inventory of the particular language. To this end, we investigated the acoustic property associated with the feature [strident] in the production of bilabial and labiodental fricatives in Ewe, and labiodental and alveolar fricatives in English, and explored whether the acoustic manifestation of the feature [strident] varied in the instantiation of [f] in Ewe and English. In Ewe, the feature [strident] plays a contrastive role distinguishing labiodental from bilabial fricatives, whereas in English the feature [strident] does not play a contrastive role. Results showed that a measure of turbulence noise was able to distinguish bilabial and labiodental fricatives in Ewe and labiodental and alveolar fricatives in English. Moreover, the range of values associated with defining the amplitude characteristics for [f] was similar in the two languages. Nevertheless, differences emerged in the acoustic fine structure of the noise amplitude for [f v] in the two languages, with the frequency distribution for the labiodental fricative in Ewe being skewed towards the high amplitude range relative to English. These results suggest that while the fundamental manifestation of the acoustic property is the same across languages, its instantiation may be influenced by the functional role that its associated feature plays in the language.
Effects of Speaking Rate Changes on Native and Nonnative Speech Production
Authors: Schmidt Anna Marie , Flege James Emil
Published: November 2009

Twenty monolingual English speakers and 40 native Spanish speakers, who were either relatively proficient or nonproficient in English, produced English /p/ at self-selected normal and fast speaking rates. The native English (NE) subjects showed much the same rate effect on voice onset time (VOT) seen in earlier studies. Native Spanish (NS) subjects who were relatively proficient in pronouncing English used fewer short-lag stops and showed an English-like rate effect on VOT. NS subjects who were relatively nonproficient in English, on the other hand, used more short-lag stops and did not show a significant speaking rate effect on VOT, although they did demonstrate speaking rate effects on vowel duration and phrase duration. Among the NS subjects were 21 whose VOT values closely matched those of the NE subjects at both speaking rates, and who showed a rate effect similar to that found for the NE subjects. Their ability to modify VOT across speaking rates suggested that these NS subjects may have established a phonetic category for English /p/.
Lengthening in Verb-Gapped Constructions
Authors: Berkovits Rochele
Published: November 2009

Verb gapping in Hebrew was studied to determine the extent to which lengthening interacts with word stress and to investigate the distribution of the lengthening effect within the syllable preceding the relevant structural boundary. Seven native speakers of Hebrew read initalstressed and final-stressed bisyllabic key words in verb-gapped constructions and in matching sentences which did not involve deletion. Lengthening in gapping primarily affected the final syllable regardless of stress and also extended back to the initial syllable. The inverse relationship between lengthening of the final syllable and the duration of a following pause, predicted by metrical theory, was not found. Within the final syllable, the vowel showed more lengthening than the final-stop closure, in contrast to the pattern of progressively greater lengthening revealed in studies of utterance-final syllables. These results suggest differences between the implementation of lengthening in gapping and at other structural boundaries.
A Probable Case of Clicks Influencing the Sound Patterns of Some European Languages
Authors: Ohala John J.
Published: November 2009

In the history of various European languages (Latin, Spanish, English, Swedish, and various dialects of French) there are instances of the cluster mn appearing as mpn. There are philological controversies as to whether this ‘epenthetic’ p was actually pronounced or was just a learned hypercorrect spelling. I offer here a novel phonetic scenario supporting the claim that the p was pronounced and arose in a phonetically natural way: I posit that in the mn cluster there was temporal overlap of the m and n closures. The simultaneous labial and apical closure would create a pocket of air between them which, when the labial closure was released, would undergo a momentary rarefaction of pressure and thus be released with a click-like burst. Listeners would be likely to interpret this stop burst auditorily as a pulmonic [p] and this would be the basis of their own pronunciations.
Determination of Glottal Excitation Cycles in Running Speech
Authors: Hess Wolfgang J.
Published: November 2009

The three-channel pitch determination algorithm (PDA) presented in this paper combines a short-term analysis PDA, which derives fundamental frequency via a periodicity criterion, and two time domain PDAs that determine the instants of glottal closure according to local signal criteria. The first of these algorithms correlates the speech signal with an estimate of the impulse response of the vocal tract; the second applies a neural network. The reliability of these time domain PDAs is increased by constraints on the range of F₀ imposed by the short-term analysis PDA. First results show that the algorithm can be applied to both accurate pitch period determination of running speech and voice quality measurements, particularly the measurements of voice jitter.
Vowel-Vowel Production: The Distinctive Region Model (DRM) and Vowel Harmony
Authors: Carré René , Bourdeau Marc , Tubach Jean-Pierre
Published: November 2009

According to the distinctive region model (DRM), sequencing one vowel to another involves one, two, or three commands or phonetic movements corresponding to specific deformations of the vocal tract. Criteria pertaining to communication theory require that these movements, or gestures, be of a small number, efficient (small deformations imply large formant variations), and simple (e.g. rectilinear movements). For a given language, the vowel-vowel transitions involving one movement should then be statistically dominant. This hypothesis is verified using a large corpus of French.
Danish Vowels – Surface Contrast versus Underlying Form
Authors: Grønnum Nina
Published: November 2009

The paper presents the outcome of some very recent sound changes, which add to the already considerable inventory of surface vowel contrasts in Danish. It claims that a classical structuralist phonological account of the vowel inventory is not satisfactory if psychological reality of phonological entities is a criterion. The only reasonable abstract representation is a morphophonological one.
Phonetic and Phonological Aspects of English Affricate Production in Children with Speech Disorders
Authors: Hardcastle William J. , Gibbon Fiona , Scobbie James M.
Published: November 2009

In this paper we consider phonetic and phonological aspects of the English voiceless affricate /t∫/ as it is realised by children with developmental speech disorders. The speakers described in the study have normal /t/ but disordered /∫/ and /t∫/. Using electropalatography (Reading EPG), we compare the stop and fricative phases of /t∫/ to independent /t/ and /∫/. This comparison shows that the place of articulation of /t∫/ can be predicted from that of independent /t/. There is a strict requirement for the affricate’s stop release to be homorganic with its fricative phase, irrespective of the place of articulation of independent /t/. Sometimes, there is also an observable coronal gesture during the stop phase of a dorsal affricate indicating the influence of independent /t/. This is predicted by phonological theories in which the affricate is related to both /t/ and /∫/ but not by theories in which the affricate is merely the stop counterpart to /∫/.
Stimulus Uncertainty and Speaker Normalization Processes in the Perception of Nasal Consonants
Authors: Haley Katarina L· , Ohde Ralph N.
Published: November 2009

Previous research has noted a reduction in perceptual identification performance when the speaker varies from stimulus to stimulus and has interpreted this finding as an effect of a normalization process that compensates for variability in the physical content of the speech signal. The purpose of the present investigation was to examine whether the physical variability introduced by this experimental design can result in general stimulus uncertainty effects that extend beyond the realm of traditional delineations of normalization processes. The stimuli were short segments taken from nasal consonant + vowel syllables produced by 1 male adult, 1 female adult, and 2 children. Segments of 25 and 50 ms duration were edited from the nasal murmur and the onset of the vowel. The stimuli were ordered according to four variability conditions and presented to listeners for place of articulation identification. The results showed that identification was significantly reduced when variability affected either speaker identity or segment type. Further analyses revealed that segment variability impaired perception of all segment types approximately equally, but that the 50-ms vowel segments were selectively spared in the speaker variability condition. These findings indicate that general uncertainty effects should be considered in speech perception experiments, and that dynamic properties of speech are particularly important in the perceptual compensation for speaker variability.
Contextual Variations in Trisyllabic Sequences of Thai Tones
Authors: Potisuk Siripong , Gandour Jack , Harper Mary P.
Published: November 2009

It is well known that tones assimilate in much the same way as consonants and vowels do. In tonal assimilation, the height and shape of a given tone is altered by adjacent tones. Earlier studies on tonal assimilation in Thai have used two-tone sequences with an intervening obstruent between the two tones of interest. In the present study, three-tone sequences were used with continuously voiced syllables throughout the utterance. Assimilatory effects were expected to be greater between F₀ contours of two successive syllables that are continuous in voicing across the syllable boundary. Stimuli consisted of 125 possible three-tone sequences of the five Thai tones, superimposed on monosyllabic words in a carrier sentence. All syllables were stressed in order to eliminate potentially confounding interactions between stress and tonal assimilation. Acoustic analysis revealed that perseverative effects were assimilatory in nature; anticipatory effects, however, were dissimilatory in nature. Perseverative effects appear to be independent of tonal categories, and restricted to contiguous tones. Perseverative effects extend through more than half the duration of the following tone. Both the height and shape of the tones are affected. Anticipatory effects, on the other hand, are limited to the high and rising tones, and extend through less than half the duration of the preceding tone.
An EMMA Study of Segmental Complexity in Alveolopalatals and Palatalized Alveolars
Authors: Recasens Daniel , Romero Joaquín
Published: November 2009

The goal of this paper is to test whether the palatal nasal stop /n/, occurring in several Romance languages, Hungarian and Czech, is a two-gesture, complex segment (produced with a tongue front closure and intentional tongue dorsum raising) or else a one-gesture, simple segment (articulated at the alveoloprepalatal zone with a single tongue portion including the lamina and predorsum). In order to investigate this issue, electromagnetic midsagittal articulometer data were collected on apical, laminal and dorsal movement data for Catalan /n/ and Russian palatalized alveolar /nj/ (which is known to be a complex segment); other sound classes of both languages were also recorded, namely, the simple palatal segment /j/ and the two-segmental cluster /nj/. Time lags between position maxima at the tongue front and at the tongue dorsum argue strongly in favor of /n/ being a simple segment: they were found to be considerably shorter for /n/ than for /nj/; moreover, those for /nj/ were significantly longer than those for /j/ in Russian but not so in Catalan. In conjunction with linguopalatal contact data from the literature, it is argued that a longer time lag for /n/ vs. /j/ is representative of an unintentional, transitional event resulting from the alveoloprepalatal closure release for the former consonant occurring at the alveolar zone earlier than at the prepalatal zone.
Exploring the Relationship of Inspiration Duration to Utterance Duration
Authors: Whalen D.H. , Kinsella-Shaw J.M.
Published: November 2009

Previous work has indicated that there may be a positive relationship between the duration and extent of inspiration and the length of an upcoming utterance. However, none of that work has uniquely implied a role of planning. We attempted to avoid some of the alternative explanations by forcing subjects to utter single sentences ranging in length from 5 to 82 syllables (mean of 27), after inspiring fully and then expiring down to a set level before uttering the sentence. For all 3 subjects, there was a significant positive relationship between utterance length and inspiration duration, regardless of whether inspiration was measured physiologically or acoustically. The 2 subjects with the higher correlations in the articulatory measures also expended air more quickly during the shorter sentences than longer ones, while the other subject had no correlation with exhalation rate. Complexity of the sentence, calculated as the number of clauses in the sentence, did not affect inspiration duration. The individual differences need further investigation, but there is a positive correlation between the duration of the sentence to be said and the inspiration before it when the speaker is required to read sentences while using only one breath.
Silent Mandibular Oscillations in Vocal Babbling
Authors: Meier Richard P. , McGarvin Lynn , Zakia Renée A.E. , Willerman Raquel
Published: November 2009

Early babbling has been characterized as being fundamentally a mandibular oscillation: the infant’s repeated lowering and raising of its mandible yields a perceived contrast between consonants produced in a closed vocal tract configuration and vowels produced with an open tract. We wondered whether babblers produce rhythmic mandibular oscillations without phonation and, if so, whether there might be a relationship between such ‘jaw wags’ and early speech. We report two studies: the first is a longitudinal, observational study of 14 infants, some of whom were hearing and some Deaf. Seven infants (3 hearing, 3 Deaf, and 1 hearing-impaired) produced numerous speech-like, rhythmic jaw wags without phonation; sometimes jaw wags formed a single utterance with phonated babbling. Most jaw wags reported here were produced when these infants were ages 8–13 months. The second study, a survey of 90 parents of 4- to 10-month-old hearing infants, suggests that silent babbles may be a widespread phenomenon of early speech development.
Production Constraints on Utterance-Final Consonant Characteristics in Babbling
Authors: Redford Melissa A. , MacNeilage Peter F. , Davis Barbara L.
Published: November 2009

In order to evaluate hypotheses regarding production constraints on final consonants in babbling, 721 utterance-final consonants produced by 6 infants in consonant-vowel-consonant (CVC) syllables were examined and compared with the preceding consonant in the CVC. Consistent with earlier studies, major patterns were observed for each of the three main consonantal properties – place and manner of articulation and voicing. These patterns included a strong tendency for final consonants to repeat the place of articulation of nonfinal consonants and a tendency for relatively more fricative, nasal and voiceless consonants to occur in final position than in nonfinal position. The high frequency with which final consonants shared place of articulation with the preceding consonant was considered to reflect ‘frame dominance’ or the tendency of a relatively constant mandibular cycle (the frame) to determine the structure of utterances with very little contribution from other active articulators. The manner and voicing effects were attributed to an overall terminal energy decrease in the vocal production system.
Serum Long-Chain n-3 Polyunsaturated Fatty Acids and Risk of Hospital Diagnosis of Atrial Fibrillation in Men
Authors: Virtanen Jyrki K. , Mursu Jaakko , Voutilainen Sari , Tuomainen Tomi-Pekka
Published: November 2009

Background—

Atrial fibrillation (AF) is a common cardiac arrhythmia. Regular fish consumption has been shown to reduce the risk of AF in some but not all studies. Long-chain n-3 polyunsaturated fatty acids (PUFAs) from fish have been suggested to account for these beneficial effects. We tested this hypothesis by studying the association between the serum long-chain n-3 PUFAs eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid and risk of AF in men.

Methods and Results—

A total of 2174 men from the prospective population-based Kuopio Ischemic Heart Disease Risk Factor Study, 42 to 60 years old and free of AF at baseline in 1984 to 1989, were studied. During the average follow-up time of 17.7 years, 240 AF events occurred. In the Cox proportional hazards model, the multivariable-adjusted hazard ratio in the highest (>5.33%) versus the lowest (<3.61%) quartile of eicosapentaenoic acid plus docosapentaenoic acid plus docosahexaenoic acid was 0.65 (95% confidence interval 0.44 to 0.96,
P
for trend=0.07). Evaluated individually, only serum docosahexaenoic acid was associated with the risk of AF (hazard ratio in the highest versus the lowest quartile 0.62, 95% confidence interval 0.42 to 0.92,
P
for trend=0.02). Exclusion of subjects (n=233) with myocardial infarction or congestive heart failure either at baseline or that preceded the AF event during follow-up slightly strengthened the associations. Serum intermediate chain-length n-3 PUFA, α-linolenic acid, or hair methylmercury concentration were not associated with the risk.

Conclusions—

An increased concentration of long-chain n-3 PUFAs in serum, a marker of fish or fish oil consumption, may protect against AF. Serum docosahexaenoic acid concentration had the greatest impact.
Noninvasive Assessment of Arterial Stiffness Should Discriminate Between Systolic and Diastolic Pressure Ranges
Authors: Hermeling Evelien , Hoeks Arnold P.G. , Winkens Mark H.M. , Waltenberger Johannes L. , Reneman Robert S. , Kroon Abraham A. , Reesink Koen D.
Published: November 2009

Arterial stiffening plays an important role in the development of hypertension and cardiovascular diseases. The intrinsically nonlinear (ie, pressure-dependent) elastic behavior of arteries may have serious consequences for the accuracy and interpretation of arterial stiffness measurements and, ultimately, for individual patient management. We determined aortic pressure and common carotid artery diameter waveforms in 21 patients undergoing cardiac catheterization. The individual pressure-area curves were described using a dual exponential analytic model facilitating noise-free calculation of incremental pulse wave velocity. In addition, compliance coefficients were calculated separately in the diastolic and systolic pressure ranges, only using diastolic, dicrotic notch, and systolic data points, which can be determined noninvasively. Pulse wave velocity at systolic pressure exhibited a much stronger positive correlation with pulse pressure (
P
<0.001) and age (
P
=0.012) than pulse wave velocity at diastolic pressure. Patients with an elevated systolic blood pressure (>140 mm Hg) had a 2.5-times lower compliance coefficient in the systolic pressure range than patients with systolic blood pressures <140 mm Hg (
P
=0.002). Most importantly, some individuals, with comparable age or pulse pressure, had similar diastolic but discriminately different systolic pulse wave velocities and compliance coefficients. We conclude that noninvasive assessment of arterial stiffness could and should discriminate between systolic and diastolic pressure ranges to more precisely characterize arterial function in individual patients.
Open Access Series of Imaging Studies: Longitudinal MRI Data in Nondemented and Demented Older Adults
Authors: Marcus Daniel S. , Fotenos Anthony F. , Csernansky John G. , Morris John C. , Buckner Randy L.
Published: November 2009

The Open Access Series of Imaging Studies is a series of neuroimaging data sets that are publicly available for study and analysis. The present MRI data set consists of a longitudinal collection of 150 subjects aged 60 to 96 years all acquired on the same scanner using identical sequences. Each subject was scanned on two or more visits, separated by at least 1 year for a total of 373 imaging sessions. Subjects were characterized using the Clinical Dementia Rating (CDR) as either nondemented or with very mild to mild Alzheimer's disease. Seventy-two of the subjects were characterized as nondemented throughout the study. Sixty-four of the included subjects were characterized as demented at the time of their initial visits and remained so for subsequent scans, including 51 individuals with CDR 0.5 similar level of impairment to individuals elsewhere considered to have “mild cognitive impairment.” Another 14 subjects were characterized as nondemented at the time of their initial visit (CDR 0) and were subsequently characterized as demented at a later visit (CDR > 0). The subjects were all right-handed and include both men (n = 62) and women (n = 88). For each scanning session, three or four individual T1-weighted MRI scans were obtained. Multiple within-session acquisitions provide extremely high contrast to noise, making the data amenable to a wide range of analytic approaches including automated computational analysis. Automated calculation of whole-brain volume is presented to demonstrate use of the data for measuring differences associated with normal aging and Alzheimer's disease.
Droplet Growth in Warm Water Clouds Observed by the A-Train. Part I: Sensitivity Analysis of the MODIS-Derived Cloud Droplet Sizes
Authors: Nakajima Takashi Y. , Suzuki Kentaroh , Stephens Graeme L.
Published: November 2009

This study examines the sensitivity of the retrieved cloud droplet radii (CDR) to the vertical inhomogeneity of droplet radii, including the existence of a drizzle mode in clouds. The focus of this study is warm water-phase clouds. Radiative transfer simulations of three near-infrared Moderate Resolution Imaging Spectroradiometer (MODIS) channels centered on wavelengths of 1.6, 2.1, and 3.7 μm reveal that the retrieved CDR are strongly influenced by the vertical inhomogeneity of droplet size including (i) the existence of small cloud droplets at the cloud top and (ii) the existence of the drizzle mode. The influence of smaller droplets at cloud top affects the 3.7-μm channel most, whereas the presence of drizzle influences radiances of both the 2.1- and 1.6-μm channels more than the 3.7-μm channel. Differences in the CDR obtained from MODIS 1.6-, 2.1-, and 3.7-μm channels that appear in global analysis of MODIS retrievals and the CDR derived from data collected during the First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment (FIRE) intensive observation period in 1987 can be explained by the results obtained from the sensitivity experiments of this study.
Using CASA IP1 to Diagnose Kinematic and Microphysical Interactions in a Convective Storm
Authors: Dolan Brenda , Rutledge Steven A.
Published: November 2009

Data from the Collaborative Adaptive Sensing of the Atmosphere (CASA) Integrated Project I (IP1) network of polarimetric X-band radars are used to observe a convective storm. A fuzzy logic hydrometeor identification algorithm is employed to study microphysical processes. Dual-Doppler techniques are used to analyze the 3D wind field. The scanning strategy, sensitivity, and low-level scanning focus of the radars are investigated for influencing bulk hydrometeor identification and dual-Doppler wind retrievals. Comparisons are made with the nearby S-band polarimetric Next Generation Weather Radar (NEXRAD) prototype radar (KOUN), for consistency. Lightning data are used as an independent indicator of storm evolution for comparison with radar observations.

A new methodology for retrieving the vertical wind utilizing upward and variational integration techniques is employed and shown to illustrate trends in mean wind, with particularly good results at low levels. IP1 observations of a case on 10 June 2007 show the development of the updraft, subsequent graupel echo volume evolution, and a descending downdraft preceded by significant graupel in the midlevels, with updraft and graupel volumes leading the onset of lightning. Many of these trends are corroborated by KOUN. The high temporal resolution of three minutes and near-ground sampling provided by IP1 is integral to resolving up- and downdrafts, as well as hydrometeor evolution. IP1 coverage of the upper levels is diminished compared to KOUN, impacting the quality of the dual-Doppler derived vertical winds and ice echo volumes, although the low-level coverage helps to mitigate some errors. However, IP1 coverage of the low- to midlevels is demonstrated to be comparable or better than coverage by KOUN for this storm location.
An Observational and High-Resolution Model Analysis of Gale Wind Events in the Gulf of California
Authors: Cohen Ariel E. , Cangialosi John P.
Published: November 2009

The Tropical Analysis and Forecast Branch (TAFB) of the National Oceanic and Atmospheric Administration’s (NOAA’s) National Hurricane Center in Miami, Florida, provides high-seas forecasts to portions of the eastern Pacific Ocean, including the Gulf of California. These forecasts include wind velocity and significant wave height forecasts and are initiated by forecast winds of at least 20 kt (10.3 m s−1) or significant wave heights of at least 8 ft (2.4 m). The Gulf of California is a commonly traveled area, where winds are highly modulated by nearby terrain variations. This provides a unique forecast challenge, especially in the absence of regular surface observations. In October and November 2008, the NOAA R/V David Starr Jordan was stationed in the Gulf of California and occasionally reported gale force winds [34–47 kt (17.5–24.2 m s−1)], which operational models regularly missed. A ship log of these events provided the basis for determining mean and anomaly fields for a handful of meteorological variables, from which a conceptual model for the synoptic-scale environment supporting these events is presented. An index based on the mean sea level pressure (MSLP) difference between Ely, Nevada, and Yuma, Arizona, was developed to measure the potential for gales, which was found to be statistically significant in discriminating between “gale” and “marginal wind” events. The fifth-generation NCAR–Pennsylvania State University Mesoscale Model (MM5) is used to conduct doubly nested high-resolution simulations centered on the Gulf of California. These simulations appeared to resolve the gales better than traditional global model guidance, lending credence toward the need for high-resolution modeling in areas of highly variable terrain. Relatively small errors were found in MM5 output using the National Aeronautics and Space Administration (NASA) Quick Scatterometer (QuikSCAT) data as verification.
Molecular events associated with epithelial to mesenchymal transition of nasopharyngeal carcinoma cells in the absence of Epstein-Barr virus genome
Authors: Lin Jung-Chung , Liao Shuen-Kuei , Lee En-Huei , Hung Man-Shan , Sayion Yiyang , Chen Hung-Chang , Kang Chen-Chen , Huang Liang-Sheng , Cherng Jaw-Ming
Published: November 2009

Epithelial-mesenchymal transition (EMT) is an important process in tumor metastasis. The EMT-related events associated with metastasis of NPC in the absence of EBV have not been elucidated. We established an EBV-negative NPC cell line from a bone marrow biopsy of an NPC patient. Using a Matrigel system we isolated an invasive and non-invasive sublines, designated NPC-BM29 and NPC-BM00. NPC-BM29 acquired an invasive-like phenotype characterized by EMT, marked by down-regulation of E-cadherin and β-catenin with concomitant increased expression of Ets1. NPC-BM29 cells expressed ≥ 10-fold higher of MMP-9 than NPC-BM00 cells. NPC-BM29 cells grew better in 2% serum than NPC-BM00 cells, with a population doubling-time of 26.8 h and 30.7 h, respectively. A marked reduction in colony-formation ability of NPC-BM00 cells compared to NPC-BM29 was observed. Wound-healing assay revealed that NPC-BM29 cells displayed higher motility than NPC-BM00 and the motility was further enhanced by cell treatment with TPA, a PKC activator. Cell surface markers and tumor-associated molecules, AE3, MAK6 and sialyl-Tn, were up-regulated in NPC-BM29 cells, whereas the expression of HLA-DR and CD54 was significantly increased in NPC-BM00 cells. NPC-BM29 consistently released higher levels of IL-8 and IL-10 than NPC-BM00, with low levels of IL-1α expression in both cell lines. Higher level of VEGF production was detected in NPC-BM00 than NPC-BM29 cells. These data show that EBV is not required for exhibiting multiple metastatic phenotypes associated with EMT. More studies that target right molecules/signalings associated with the EMT may offer new therapeutic intervention options for NPC invasion and metastasis.
Prevention of elastase-induced emphysema in placenta growth factor knock-out mice
Authors: Cheng Shih Lung , Wang Hao Chien , Yu Chong Jen , Tsao Po Nien , Carmeliet Peter , Cheng Shi Jung , Yang Pan Chyr
Published: November 2009

Background

Although both animal and human studies suggested the association between placenta growth factor (PlGF) and chronic obstructive pulmonary disease (COPD), especially lung emphysema, the role of PlGF in the pathogenesis of emphysema remains to be clarified. This study hypothesizes that blocking PlGF prevents the development of emphysema.

Methods

Pulmonary emphysema was induced in PlGF knock-out (KO) and wild type (WT) mice by intra-tracheal instillation of porcine pancreatic elastase (PPE). A group of KO mice was then treated with exogenous PlGF and WT mice with neutralizing anti-VEGFR1 antibody. Tumor necrosis factor alpha (TNF-α), matrix metalloproteinase-9 (MMP-9), and VEGF were quantified. Apoptosis measurement and immuno-histochemical staining for VEGF R1 and R2 were performed in emphysematous lung tissues.

Results

After 4 weeks of PPE instillation, lung airspaces enlarged more significantly in WT than in KO mice. The levels of TNF-α and MMP-9, but not VEGF, increased in the lungs of WT compared with those of KO mice. There was also increased in apoptosis of alveolar septal cells in WT mice. Instillation of exogenous PlGF in KO mice restored the emphysematous changes. The expression of both VEGF R1 and R2 decreased in the emphysematous lungs.

Conclusion

In this animal model, pulmonary emphysema is prevented by depleting PlGF. When exogenous PlGF is administered to PlGF KO mice, emphysema re-develops, implying that PlGF contributes to the pathogenesis of emphysema.
Immunization protected well nourished mice but not undernourished ones from lung injury in Methicillin-resistant Staphylococcus aureus(MRSA) infection
Authors: França Thais Graziela Donegá , Ishikawa Larissa Lumi Watanabe , Zorzella-Pezavento Sofia Fernanda Gonçalves , Chiuso-Minicucci Fernanda , Guerino Clara Pires Fujiara , da Cunha Maria de Lourdes Ribeiro de Souza , Sartori Alexandrina
Published: November 2009

Background

Staphylococcus aureus methicillin-resistant (MRSA) has been frequently isolated from endotracheal and lung puncture aspirates in malnourished children with pneumonia. In this work we evaluated the susceptibility of undernourished BALB/c mice and its ability to mount a protective immunity against MRSA with emphasis on the lung involvement.

Results

BALB/c mice submitted to a 20% dietary restriction during 20 days presented a significant decrease in body weight, lymphocyte number and also atrophy in thymus and intestinal epithelium. Determination of bacterial load by the number of colony forming units (CFU) indicated a similar susceptibility whereas the findings of Gram stain clearly suggested a higher amount of bacteria in the lungs of normal mice than in the undernourished ones. Immunization reduced bacterial growth in the lungs of normal mice but not in the undernourished ones. Histopathological analysis showed that inflammation appeared in the lungs from normal mice only after infection and that immunization prevented this pulmonary inflammatory process. On the other hand, undernourished mice presented lung inflammation even before infection. In addition, the degree of this inflammatory process did not change with infection or previous immunization.

Conclusion

Our results indicated that lung injury during MRSA infection is prevented by previous immunization in well nourished but not in undernourished mice.