Degree Of Constriction Research Articles

Introducing the Rhamphoriaceae, fam. nov. (Sordariomycetes), two new genera, and new life histories for taxa with Phaeoisaria- and Idriella-like anamorphs

ABSTRACTTwo new genera, Rhamphoriopsis and Xylolentia, are described for lignicolous perithecial ascomycetes occurring in terrestrial habitats. Fresh material, living cultures, morphology, and DNA sequence data (nuc rDNA internal transcribed spacers [ITS1-5.8S-ITS2 = ITS], 18S and 28S genes, and second largest subunit of RNA polymerase II = RPB2) of these taxa and morphologically similar fungi were studied to determine their relationships. A monophyletic clade including Rhamphoria, Rhodoveronaea, a dematiaceous hyphomycete Linkosia multiseptum, and the two new genera was recovered in the Sordariomycetes based on the 18S-28S-RPB2 data set. It is introduced as the family Rhamphoriaceae and strongly supported by Bayesian and maximum likelihood methods. Its members are characterized by perithecial ascomata with a cylindrical or rostrate neck, the absence of stromatic tissue or clypeus, similar anatomy of two-layered ascomatal walls, cylindrical paraphyses, unitunicate asci with a distinct, nonamyloid apical annulus, and dictyoseptate or transversely septate, hyaline or brown ascospores. The mode of conidiogenesis is holoblastic, predominantly on polyblastic-denticulate conidiogenous cells. The Phaeoisaria-like anamorph has been linked to Rhamphoria and Rhamphoriopsis, whereas conidia and conidiophores of Idriella-like synanamorph were formed in vitro in two species of Rhamphoria. The Veronaea-like anamorph is associated with Rhodoveronaea. The anamorph of Xylolentia is a dematiaceous hyphomycete with conidiogenous cells with sympodially extending rachis. A key to members of the family is provided. The classification and nature of species boundaries in Rhamphoria are discussed, and diagnostic characters such as ascospore shape, number of transverse and longitudinal septa, a degree of constriction at the septa, and ability to produce ascoconidia are evaluated.

Enhanced arc-acoustic interaction by stepped-plate radiator in ultrasonic wave-assisted GTAW

Through different physical and welding experiments, performance of the stepped-plate radiator configuration with varying height and diameter was compared. Arc characteristic measurements show a constriction of the arc column and hence an increase in arc pressure. The variation in arc profile is not linear but a wavelike feature with increasing radiator height. As for radiator diameter, there only exists one wave trough at the fitting curve. Acoustic field simulations verify the maximum acoustic pressure in arc burning zone, consistent with experiments that the maximum constriction degree of welding arc indeed exists in practice. Microstructures of weld metal prepared with ultrasonic vibration indicate the significant grain refinement compared to those without ultrasonic vibration under the same heat input. Ultrasonic wave emitted from the designed radiator generates a large acoustic pressure, which features a concave shape at weld pool zone. Arc-acoustic interaction with a soft reflector of weld pool can be improved by greatly enhancing the acoustic field level through optimizing the stepped-plate radiator configuration.

A Preliminary Videofluoroscopic Investigation of Swallowing Physiology and Function in Individuals with Oculopharyngeal Muscular Dystrophy (OPMD).

Dysphagia is one of the primary symptoms experienced by individuals with Oculopharyngeal Muscular Dystrophy (OPMD). However, we lack understanding of the discrete changes in swallowing physiology that are seen in OPMD, and the resulting relationship to impairments of swallowing safety and efficiency. This study sought to describe the pathophysiology of dysphagia in a small sample of patients with OPMD using a videofluoroscopy examination (VFSS) involving 3 × 5mL boluses of thinliquid barium (22% w/v). The aim of this study is to extend what is known about the pathophysiology of dysphagia in OPMD, by quantifying changes in swallow timing, kinematics, safety, and efficiency, measured from VFSS. This study is a secondary analysis of baseline VFSS collected from 11 adults (4 male), aged 48-62 (mean 57) enrolled in an industry-sponsored phase 2 therapeutic drug trial. Blinded raters scored the VFSS recordings for safety [Penetration-Aspiration Scale (PAS)], efficiency [Normalized Residue Ratio Scale (NRRS)], timing [Pharyngeal Transit Time (PTT), Swallow Reaction Time (SRT), Laryngeal Vestibule Closure Reaction Time (LVCrt), Upper Esophageal Sphincter Opening Duration (UESD)], and kinematics (hyoid movement, pharyngeal constriction, UES opening width). Impairment thresholds from existing literature were defined to characterize swallowing physiology and function. Further, Fisher's Exact tests and Pearson's correlations were used to conduct a preliminary exploration of associations between swallowing physiology (e.g., kinematics, timing) and function (i.e., safety, efficiency). Compared to published norms, we identified significant differences in the degree of maximum pharyngeal constriction, hyoid movement distance and speed, as well as degree and timeliness of airway closure. Unsafe swallowing (PAS ≥ 3) was seen in only 3/11 patients. By contrast, clinically significant residue (i.e., NRRS scores ≥ 0.09 vallecular; ≥ 0.2 pyriform) was seen in 7/11 patients. Fisher's Exact tests revealed associations between prolonged SRT, PTT, and unsafe swallowing. Weak associations were also identified between post-swallow residue and poor pharyngeal constriction during the swallow. Detailed analysis of swallowing physiology in this series of adults with OPMD aligns with impaired muscular function (e.g., reduced pharyngeal constriction, incomplete laryngeal vestibule closure) associated with the disease, and primary functional challenges with swallow efficiency. Further work is needed to explore a greater range of food and liquid textures, and to identify additional physiological mechanisms underlying swallowing impairment in OPMD.

Calculating the Hydrodynamic Characteristics of the Active Section of the Self-Draining Solar Loop of a Heating System

The article considers experimental studies of the hydrodynamic characteristics of the active section of the self-draining solar loop of a heating system. This element is designed as a flow constrictor referred to as Ventury tube, with a high degree of flow constriction of 2–5 in the region with strong viscous resistance. The experimental data are processed in a criteria form, the general type of which is obtained by dimensional technique and compared with data from other authors. The obtained criteria dependences can be used to calculate the hydrodynamic characteristics of the active section of the self-draining solar loop of a heating system.

Noninvasive Estimation of Pressure Changes Using 2-D Vector Velocity Ultrasound: An Experimental Study With In Vivo Examples.

A noninvasive method for estimating intravascular pressure changes using 2-D vector velocity is presented. The method was first validated on computational fluid dynamic (CFD) data and with catheter measurements on phantoms. Hereafter, the method was tested in vivo at the carotid bifurcation and at the aortic valve of two healthy volunteers. Ultrasound measurements were performed using the experimental scanner SARUS, in combination with an 8 MHz linear array transducer for experimental scans and a carotid scan, whereas a 3.5-MHz phased array probe was employed for a scan of an aortic valve. Measured 2-D fields of angle-independent vector velocities were obtained using synthetic aperture imaging. Pressure drops from simulated steady flow through six vessel geometries spanning different degrees of diameter narrowing, running from 20%-70%, showed relative biases from 0.35% to 12.06%, depending on the degree of constriction. Phantom measurements were performed on a vessel with the same geometry as the 70% constricted CFD model. The derived pressure drops were compared to pressure drops measured by a clinically used 4F catheter and to a finite-element model. The proposed method showed peak systolic pressure drops of -3 kPa ± 57 Pa, while the catheter and the simulation model showed -5.4 kPa ± 52 Pa and -2.9 kPa, respectively. An in vivo acquisition of 10 s was made at the carotid bifurcation. This produced eight cardiac cycles from where pressure gradients of -227 ± 15 Pa were found. Finally, the aortic valve measurement showed a peak pressure drop of -2.1 kPa over one cardiac cycle. In conclusion, pressure gradients from convective flow changes are detectable using 2-D vector velocity ultrasound.

Evidence and characterization of a glide-vowel distinction in American English

<p class="p1">This study tests whether native speakers of American English exhibit a glide-vowel distinction ([j]-[i]) in a speech elicitation experiment. When reading sentences out loud, participants’ pronunciations of 4 near-minimal pairs of pre-existing lexical items (e.g., <em>Eston</em>[iə] vs. <em>pneumon</em>[jə]) exhibit significant differences when acoustically measured, confirming the presence of a [j]-[i] distinction. This distinction is also found to be productively extended to the production of 20 near-minimal pairs of nonce words (e.g., <em>Súmia </em>→ [sumiə] vs. <em>Fímya </em>→ [fimjə]), diversified and balanced along different phonologically relevant factors of the surrounding environment. Multiple acoustic measurements are compared to test what aspects most consistently convey the distinction: F2 (frontness), F1 (height), intensity, vocalic sequence duration, transition earliness, and transition speed. This serves the purpose of documenting the distinction’s acoustic phonetic realization. It also serves in the comparison of phonological representations. Multiple types of previously proposed phonological representations are considered along with the competing predictions they generate regarding the acoustic measurements performed. Results suggest that the primary and most consistent characteristic of the distinction is earliness of transition into the following vowel, with results also suggesting that the [j] glide has a greater degree of constriction. The [j] glide is found to have a significantly <em>less </em>anterior articulation, challenging the application of a representation based on place or articulator differences that would predict [j] to be <em>more </em>anterior.

Numerical Simulations of the Motion and Deformation of Three RBCs during Poiseuille Flow through a Constricted Vessel Using IB-LBM

The immersed boundary-lattice Boltzmann method (IB-LBM) was used to examine the motion and deformation of three elastic red blood cells (RBCs) during Poiseuille flow through constricted microchannels. The objective was to determine the effects of the degree of constriction and the Reynolds (Re) number of the flow on the physical characteristics of the RBCs. It was found that, with decreasing constriction ratio, the RBCs experienced greater forced deformation as they squeezed through the constriction area compared to at other parts of the microchannel. It was also observed that a longer time was required for the RBCs to squeeze through a narrower constriction. The RBCs subsequently regained a stable shape and gradually migrated toward the centerline of the flow beyond the constriction area. However, a sick RBC was observed to be incapable of passing through a constricted vessel with a constriction ratio ≤1/3 for Re numbers below 0.40.

Tracking developmental changes in articulatory strategy during childhood

During development, children learn how to coordinate movements of the speech articulators in order to optimally achieve motor goals. It has been shown that variability in these coordinative patterns, or articulatory strategies, decreases over the course of childhood before ultimately stabilizing at adult-like levels. For example, the jaw becomes more tightly coordinated with the tongue and lips. Recent advances in real-time magnetic resonance imaging (rt-MRI) and analysis provide a means to characterize such articulatory strategies by quantifying how much the jaw, tongue, lips, velum, and pharynx contribute to constrictions of the vocal tract during speech. The articulators are segmented in reconstructed rt-MRI and constriction degrees are measured as the linear distance between opposing structures (e.g., tongue and palate). Change in constriction degree over time is decomposed into articulator contributions to characterize articulatory strategy. In this pilot study, we obtain quantitative biomarkers of articulatory strategies from a 10-year-old participant and compare them against those of 8 healthy adult participants. The study quantifies the difference between child and adult articulatory strategies in terms of how much each articulator contributes to constrictions of the vocal tract during speech and indicates how the articulator movements are coordinated with each other in time.

Articulatory differences between glides and vowels

Glides bear similarities to both consonants and vowels, and align with different classes of phonological patterns in different languages. Limited prior studies have suggested that glides are realized with a greater degree of constriction and a shorter duration than vowels, but articulatory studies are rare and we do not know the relative importance of these properties. To determine how glides differ from vowels gesturally, an articulatory study was conducted with EMA. A two-dimensional stimuli continuum was constructed by manipulating the intensity and duration of high vowels (i, u) flanked by a low vowel (a), from a vowel-like extreme to a glide-like extreme, and participants were asked to imitate these stimuli immediately after hearing them. Results show interesting asymmetries and interactions; while intensity was not directly imitated through degree of constriction, it did affect intergestural timing, with low-intensity stimuli yielding shorter durations in production. The relationship between glides and vowels is more nuanced than any single featural difference.

The role of prosodic structure in the L2 acquisition of Spanish stop lenition

This study tests the hypothesis that late first-language English / second-language Spanish learners (L1 English / L2 Spanish learners) acquire spirantization in stages according to the prosodic hierarchy (Zampini, 1997, 1998). In Spanish, voiced stops [b d g] surface after a pause or nasal stop, and continuants [β̞ ð̞ ɣ̞] surface postvocalically, among other contexts. We adopt an Optimality Theoretic analysis of the phenomenon that assumes that postvocalic continuants surface due to the ranking of prosodic positional faithfulness constraints below a markedness constraint that prohibits stops in postvocalic position. L1 English speakers are presumed to start with a ranking in which prosodic positional faithfulness outranks the markedness constraint. In line with the Gradual Learning Algorithm (Boersma and Hayes, 2001), gradual demotion of the relevant faithfulness constraints is predicted in L2 Spanish, extending the prosodic domain until continuants surface postvocalically across domains. A cross-section of 44 L1 English / L2 Spanish learners and a control group ( n = 5) completed a recitation task, and data were analysed acoustically for manner of articulation and degree of constriction. Results partially align with Zampini’s impressionistic data: Learners first produce underlying stops as postvocalic approximants at the onset of the syllable (word-medial position), followed by the onset of the prosodic word (word-initial position). Unlike Zampini’s findings, there is no evidence for an intermediate stage of acquisition across the boundary of a word and its clitic. Advanced L2 learners produce continuants in postvocalic position at all applicable prosodic levels, which we take to indicate acquisition of the target ranking. We also examined whether learners’ postvocalic continuants are lenited to the same degree as the control group, and whether degree of lenition changes across development. The difference in degree of lenition between controls and learners lessens at higher levels of the prosodic hierarchy as acquisition progresses, and several advanced learners produce target-like segments across prosodic levels.

Vocal Characteristics and Laryngoscopic Findings in Future Musical Theater Performers

Musical theater performers are a special group of elite vocal performers with a high vocal load as they combine singing, acting, and physical performance. As they are absolutely depending on their voice quality and vocal capacities for their studies and their future profession, an optimal voice production is very important. The purpose of this study was to determine the voice quality of musical theater students. The voice quality of seven students was then reevaluated 1 year after the first assessment. Observational study. Thirty-one musical students (7 men and 24 women) with a mean age of 20 years participated in the study. To determine the voice quality, objective (aerodynamic measurements, voice range profile, acoustic analysis, and Dysphonia Severity Index) and subjective (videolaryngostroboscopy, Voice Handicap Indexes, and questionnaires regarding voice symptoms and risk factors) voice measurements were performed. The median Dysphonia Severity Index in male and female musical students was respectively 5.3 and 5.7, both corresponding with an overall good voice quality. The questionnaires revealed the presence of vocal fatigue, dryness of the throat, vocal tract discomfort, and harmful vocal habits in the majority of students. In 45% of the subjects, videolaryngostroboscopic evaluation of the vocal folds showed an organic lesion. The majority of these lesions are inflammatory lesions (26%). In 68% of the subjects, a certain degree of supraglottic constriction was observed. Despite the overall good voice quality, videolaryngostroboscopy showed a high presence of vocal fold lesions and supraglottic constriction during phonation.

Determination of the critical values of flow parameters characteristic of the alignment of cylindrical nano-objects in suspensions

A method for determining the critical values of the flow speed and the flow constriction degree characteristic of the alignment of cylindrical nano-objects in a flowing suspension is proposed. Previously, the alignment process of cylindrical nano-objects in suspensions was investigated by using birefringence of the polarized light and the small-angle X-ray scattering. While both methods are suitable for measuring the alignment degree of cylindrical nano-objects in suspensions diluted down to low concentrations, they are restricted for the application to undiluted concentrated suspensions because of non-transparency and multiple scattering of X-rays. In addition, the use of the second method requires an expensive synchrotron equipment. We present a simple and faster method based on the direct ultrasound attenuation measurements of longitudinal viscosity of a suspension containing cylindrical nano-objects, which decreases monotonically, approaching its asymptotic value with increase in the flow speed and the flow constriction degree. The principle and advantages of the proposed method are as follows:•The cylindrical nano-objects align along an accelerated flow at overcritical values of the flow speed and the constriction degree.•The critical values correspond to the state of a suspension possessing viscosity close to the asymptotic value.•The method is applicable to undiluted concentrated suspensions, including opaque ones.

Effect of Domain Initial Strengthening on Vowel Height and Backness Contrasts in French: Acoustic and Ultrasound Data.

Phonetic variation due to domain initial strengthening was investigated with respect to the acoustic and articulatory distinctiveness of vowels within a subset of the French oral vowel system /i, e, ɛ, a, o, u/, organized along 4 degrees of height for the front vowels and 2 degrees of backness at the close and midclose height levels. Acoustic and lingual ultrasound data were examined to characterize the production of vowels in intonational phrase initial position, compared with intonational phrase medial position, for 4 speakers. Formant values and estimates of lingual constriction location and degree differed according to the prosodic position independent of vowel duration, with a higher F1 for /a/, a higher F2 for /ɛ/, a backer constriction for /o/ and /a/ but a fronter constriction for /ɛ/, and a narrower constriction for /e, ɛ, u, o/ but a wider constriction for /a/. For most speakers, these variations enlarge the acoustic and/or articulatory distance between members of the pairs /e-ɛ/, /ɛ-a/, /u-o/, /i-u/, and /e-o/ but reduce the distinction within the pair /i-e/. These changes in intonational phrase initial position are vowel dependent and frequently contribute to augmenting the phonetic distinctiveness between vowels contrasting along the height and backness dimensions.

Articulatory and acoustic realization of French and German /R/

French uvular /ʁ/ is usually considered as problematic due to its variability, especially in positions such as word initial and word final. In this study, an articulatory (EMA) and aerodynamic experiment allowed us to determine its major axes of variation. We show that the degree of constriction between the tongue and the palate is related to the voicing of the consonant and we validate the use of a harmonic-to-noise ratio for the measurement of variation of /ʁ/. Aerodynamic data also show that the variation of Nasal Airflow is not significant but a ratio between Oral Airflow and Intra-Oral Pressure significantly varies according to the different realizations of /ʁ/. Subglottic Pressure only plays a significant role in specific cases. These results allow us to propose a new acoustic measurement for the variation in uvular /ʁ/ production. An acoustic study is then presented on large corpora of continuous speech, so as to test the variability of French /ʁ/ in terms of the aforementioned results, and we show...

The effect of training in producing continuous vowels with a data-glove-driven vocal tract configuration tool

This paper describes vocal tract configuration for continuous vowels by using a data glove. The authors have proposed data-glove-driven vocal tract configuration methods and showed the usefulness of a method with three fingers for producing vowel sounds. In the method, the location of constriction, the degree of constriction, and the lip area are controlled by bending the thumb, middle finger, and index finger, respectively. Moreover, the effectiveness of training for continuous vowels was shown for sequence /aiueo/. Whether any combination of vowels can be synthesized by this method is an interesting topic for confirmation of the effectiveness. To examine the possibility of successful manipulation of the data glove, an experiment for synthesizing various three consecutive vowels was performed with five beginner subjects. Japanese vowel sequences of 60 patterns were used in the experiment. The results proved that the subjects were able to successfully produce the vowel sequences immediately after showing a target sequence through three training sessions for manipulating the data glove.

The Gesture as an Autonomous Nonlinear Dynamical System

ABSTRACTWe propose a theory of how the speech gesture determines change in a functionally relevant variable of vocal tract state (e.g., constriction degree). A core postulate of the theory is that the gesture determines how the variable evolves in time independent of any executive timekeeper. That is, the theory involves intrinsic timing of speech gestures. We compare the theory against others in which an executive timekeeper determines change in vocal tract state. Theories that employ an executive timekeeper have been proposed to correct for disparities between theoretically predicted and experimentally observed velocity profiles. Such theories of extrinsic timing make the gesture a nonautonomous dynamical system. For a nonautonomous dynamical system, the change in state depends not just on the state but also on time. We show that this nonautonomous extension makes surprisingly weak kinematic predictions both qualitatively and quantitatively. We propose instead that the gesture is a theoretically simpler nonlinear autonomous dynamical system. For the proposed nonlinear autonomous dynamical system, the change in state depends nonlinearly on the state and does not depend on time. This new theory provides formal expression to the notion of intrinsic timing. Furthermore, it predicts experimentally observed relations among kinematic variables.

Speech analysis-synthesis system using principal components of vowel spectra

We have studied an effective method using principal components spanning a feature space of isolated vowels. A covariance matrix is calculated from many log-amplitude spectra of isolated vowels uttered by a speaker. An eigen equation of the covariance matrix is solved. The resulting eigenvectors are called principal vectors. In the analysis system, log-amplitude spectrum for each frame of a word uttered by the same speaker is transformed to the components on the principal vectors. In the synthesis system, a log-amplitude spectrum is reconstructed using the components on the principal vectors with the largest eigenvalues and the spoken word is synthesized using the LMA filter. We draw the distribution chart of the first and the second principal components extracted from Japanese vowel data. This figure was very similar to the F1—F2 distribution of vowels and so to the vowel classification map in coordinate axes of the degree of constriction and the tongue hump position. The Listening tests showed that the q...

Effect of Constriction on Phonon Transport in Silicon Thin Films and Nanowires

Technological advancement has made manufacturing of various nanostructures possible. Thermal transport in such nanostructures is fundamentally different from macroscale. Initial studies have indicated that thermal properties of these nanostructures also depend on its geometry. Hence, it is possible to tailor nanostructure geometry to achieve targeted thermal properties. In the present work, thermal transport in (a) constricted thin films and (b) constricted nanowires is studied using gray phonon Boltzmann transport equation (BTE) for a wide range of constriction ratio. Finite volume method is used to numerically solve the BTE with the relaxation time approximation. We show in this paper that by varying the degree of constriction, thermal conductivity of thin films and nanowires can be altered significantly. Thin films and nanowires are found to respond differently to constriction.

Acoustic Correlates of the Spanish Tap-Trill Contrast: Heritage and L2 Spanish Speakers

The present study investigates the acoustic correlates of the Spanish tap-trill phonological contrast (/ɾ/-/r/) in the production of 40 Spanish heritage speakers and 20 L2 Spanish learners in Northern California. The acoustic analyses examined the number of occlusions and overall duration in the production of phonemic trills, while the phonetic variants of the phonemic tap were based on the degree of apical constriction: true tap, approximant tap, and perceptual tap. The results from a reading-aloud task indicate that most speakers produced non-canonical phonemic trills with one or zero occlusions and maintain the Spanish tap-trill phonological contrast largely by means of segmental duration, and that this is especially true for L2 learners and English-dominant heritage speakers. In contrast, Spanish-dominant heritage speakers produced the majority of their trills with two or three brief occlusions between the tongue apex and the alveolar ridge. These data confirm that heritage speakers are a heterogeneous group and that variance in their rhotic production is a result of language dominance: English-dominant heritage speakers and L2 learners are most likely to exhibit a modified system to maintain the rhotic phonological contrast in comparison to Spanish-dominant heritage speakers. The findings of this study add to our understanding of the sources of variation in heritage and L2 pronunciation by investigating a largely understudied bilingual population that has traditionally been ignored in bilingual phonetic research.

Quantifying the appearance of jackets with adhesive interlinings

Purpose – The purpose of this paper is to quantitatively evaluate the effect of adhesive interlining on the appearance of tailored jackets with different rigidity. Design/methodology/approach – Four tailored jackets having the same pattern and fabric and three different adhesive interlinings or no adhesive interlining were prepared as experimental samples. Criteria and characteristics for assessing jacket appearance were investigated in sensory tests. A paired comparison of the jacket appearance was conducted using a ranking method. Smoothness and constriction values were proposed and obtained using three-dimensional shape data. The smoothness value refers to the degree of wrinkling on the jacket surface and the constriction value refers to the degree of constriction of the waistline. A quantitative assessment model of jacket appearance was proposed using multiple regression analysis. Findings – The sensory test reveals that the number of wrinkles, acceptability of wrinkling and degree of constriction of the waist are important criteria in the assessment of jacket appearance. The smoothness value for the front body and the constriction value of the waist partially agreed with the normal scores of sensory test results. Sensory evaluation values for the entire jacket appearance were estimated employing multiple regression analysis with the constriction and smoothness values. The values of jacket appearance estimated using multiple regression analysis were in good agreement with the sensory test results. Originality/value – Criteria and characteristics to be used in the assessment of the appearance of a jacket with adhesive interlining were clarified. Employing the proposed methodology, it is possible to predict jacket appearance for different adhesive interlinings, quantitatively.