Correlates of vowel clarity in the spectrotemporal modulation domain: Application to speech impairment evaluation.

This article reports on vowel clarity metrics based on spectrotemporal modulations of speech signals. Motivated by previous findings on the relevance of modulation-based metrics for speech intelligibility assessment and pathology classification, the current study used factor analysis to identify regions within a bi-dimensional modulation space, the magnitude power spectrum, as in Elliott and Theunissen [(2009). PLoS Comput. Biol. 5(3), e1000302] by relating them to a set of conventional acoustic metrics of vowel space area and vowel distinctiveness. Two indices based on the energy ratio between high and low modulation rates across temporal and spectral dimensions of the modulation space emerged from the analyses. These indices served as input for measurements of central tendency and classification analyses that aimed to identify vowel-related speech impairments in French native speakers with head and neck cancer (HNC) and Parkinson dysarthria (PD). Following the analysis, vowel-related speech impairment was identified in HNC speakers, but not in PD. These results were consistent with findings based on subjective evaluations of speech intelligibility. The findings reported are consistent with previous studies indicating that impaired speech is associated with attenuation in energy in higher spectrotemporal modulation bands.

Validation of an Intelligibility Test Based on Acoustic-Phonetic Decoding of Pseudo-Words: Overall Results from Patients with Cancer of the Oral Cavity and the Oropharynx.

OBJECTIVES: Loss of intelligibility is a major complaint for patients with speech disorders, as it affects their everyday communication and thus contributes to a decrease in their quality of life. Several tests are available to measure intelligibility, but these tests do not take into account the evaluators' ability to restore distorted sequences. Due to this ability, the evaluator will tend to recognize words despite phonetic distortions, and speech production deficit can go undetected. The results of these tests therefore overestimate the intelligibility of patients and may mask real functional limitations. We propose a new test which uses a large number of pseudowords in order to neutralize the unwanted perceptual effects that cause this overestimation. The purpose of this test is to measure the speech production deficit. It is not intended to assess the communication deficit. Our objective is to validate this test based on acoustic-phonetic decoding of productions from patients with speech disorders. MATERIALS AND METHODS: We tested this method with a population of 39 healthy participants and 78 post-treatment patients with cancers of the oral cavity and the oropharynx (HNC patients). Each speaker produced 52 pseudowords taken from randomly generated lists from large common dictionary, each list of 52 pseudowords containing the same number of phonemes. Forty everyday listeners then transcribed these productions. The orthographic transcriptions were phonetized and compared to the expected phonetic forms. An algorithm provided a Perceived Phonological Deviation score (PPD) based on the number of features that differed between the expected forms and the transcribed items. The PPD thus provided a score representing the loss of intelligibility. RESULTS: The 39 participants in the control group demonstrated significantly lower PPD scores compared to the 41 patients with a T1T2 tumor size or compared to the 37 patients with a T3T4 tumor size. The differences between the three groups were significant. If we use the PPD as a predictor to identify patients versus control group subjects, the AUC of the ROC curve is equal to 0.94, which corresponds to an outstanding group separability. A PPD threshold at 0.6 features per phoneme is the boundary between normal and dysfunctional speech. The analysis showed a close correlation between the PPD and a clinical judgment of the disorder severity obtained from experts. CONCLUSION: This test appears to be effective in measuring the intelligibility of speakers at a phonological level, in particular in the case of head and neck cancers.

Impact of the Carbene Derivative Charge on the Decomposition Rates of Hoveyda-Grubbs-like Metathesis Catalysts.

Hoveyda-Grubbs metathesis catalysts undergo a relatively fast decomposition in the presence of olefins. Using a computational density functional theory approach, we show that positively charged derivatives of N-heterocyclic carbenes have little impact on the degradation/deactivation rates of such catalysts with respect to neutral carbenes. On the other hand, the hypothetical anionic Hoveyda-Grubbs-like catalysts are predicted to less likely undergo degradation in the presence of the olefin, while being as active as standard, neutral Hoveyda-Grubbs catalysts.

Azoliniums, Adducts, NHCs and Azomethine Ylides: Divergence in Wanzlick Equilibrium and Olefin Metathesis Catalyst Formation.

The dimerization of a saturated N-heterocyclic carbene (NHC) to tricyclic piperazine in preference to the commonly observed Wanzlick dimerization is presented. Mechanistic investigations revealed that the N-fluorene substituent of the heterocycle is implicated in both ring opening of corresponding carbene dimer and tautomerization of NHC to an azomethine ylide. This has consequences for the fate of the NHC when generated from either an azolinium salt or a pentafluorophenyl adduct. The insights gained permitted the synthesis of a new indenylidene metathesis precatalyst, which exhibits exceptional selectivity and high TONS in self-metathesis of 1-octene.

Breast education for schoolgirls; why, what, when, and how?

Schools are fundamental settings for health education and adolescent females are an important group for promoting positive breast habits. We surveyed 2089 schoolgirls (11-18 years) to provide evidence for, and guidance on, breast education for schoolgirls. 26% reported negative feelings about their breasts and 87% reported ≥ one breast concern. 72% wanted to know more about breast cancer (69% rating this extremely important). >50% wanted to know more about breast sag and breast pain. Preferred delivery format was age eleven (50%), girls only taught sessions (41%) with female teachers (43%). A need for breast education and delivery preferences was identified.

Temporal control in the voicing contrast: Evidence from surgery-related apraxia of speech.

The goal of this study was to investigate the phonetic realisation of the voicing feature in two tumour resection-related Spanish speakers with apraxia of speech. Temporal parameters related to the phonological contrast of voicing in Spanish have been analysed for intervocalic voiced and voiceless obstruents embedded in isolated words and nonwords, and compared with data collected from healthy speakers. Results indicate that in devoiced productions, where VOT values fitted the 'voiceless stops' category, vowel duration values matched those of voiced stops and suggested the preservation of contextual voicing cues. An attempt at preserving a consonant/vowel duration ratio consistent with aerodynamic predictions for voicing contrast has been observed in apraxic correct production as well as in devoicing errors, but not in the control group, which could be interpreted as a compensatory mechanism.

Confrontation between Penicillium rubens and Aspergillus terreus: Investigating the production of fungal secondary metabolites in submerged co-cultures.

The production of secondary metabolites in the submerged co-cultures of Penicillium rubens Wisconsin 54-1255 and Aspergillus terreus ATCC 20542 was evaluated. The biosynthetic capabilities of the two strains were compared in a set of diverse liquid media that differed with respect to the initial levels of glucose, lactose and yeast extract, contained carrot juice or vegetable/turkey puree as additional nutrient sources or were supplemented with phenylacetic acid, the side-chain precursor of penicillin G. The main goal of the study was to investigate the interactions between A. terreus and P. rubens that might contribute to the changes of secondary metabolite titers. Briefly, the biosynthesis of octaketide metabolites (+)-geodin and asterric acid was visibly enhanced as a result of replacing the conventional monocultures with the co-culture systems, but solely in the media containing not more than 5 g L-1 of yeast extract. By contrast, no marked enhancement was observed with respect to the biosynthesis of penicillin G, lovastatin, chrysogine, 4a,5-dihydromevinolinic acid and 3α-hydroxy-3,5-dihydromonacolin L acid. It was shown that the relationships between medium composition and product titers were clearly different in monoculture variants than in the corresponding co-cultures. Finally, it was demonstrated that the utilization of penicillin precursors by P. rubens can be blocked under the conditions of co-cultivation.

The Influence of the Breast on Sport and Exercise Participation in School Girls in the United Kingdom.

PURPOSE: Emerging evidence suggests that breasts may be a barrier to physical activity for adult females. With only 12% of the UK 14-year-old girls achieving exercise guidelines, to understand deterrents to exercise in this population, we should consider whether breasts may also influence sport and exercise participation in school girls. This survey-based study investigated the influence of the breast on sport and exercise participation and breast-specific concerns in the UK school girls. METHODS: A survey was developed to assess demographics, breast characteristics, breast-specific concerns in sports, breast knowledge, views on breast education, and sport participation. Chi-squared tests assessed associations between participation and breast size, sports bra use, and breast concerns. RESULTS: Two thousand eighty-nine school girls aged 11-18 years completed the survey, for 97 their breasts had begun developing and 96% reported wearing breast support. Forty-six percent of girls reported that their breasts had some effect on their participation in compulsory sports and exercise, which was more prevalent in girls aged 13-14 years (51%) and in larger-breasted girls (63%). More than 50% reported never wearing a sports bra during sports. Breast concerns were high with 73% reporting ≥1 breast-specific concern in sports; with breast bounce being most prevalent (38%). CONCLUSIONS: As most of the breast concerns raised in this survey could be addressed via education and 87% of girls wanted to know more about breasts, this study demonstrates a need for breast education for school girls, which may reduce the influence of the breast on sport and exercise participation.