927 resultados para Voice preservation


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Both commercial and scientific applications often need to transform color images into gray-scale images, e. g., to reduce the publication cost in printing color images or to help color blind people see visual cues of color images. However, conventional color to gray algorithms are not ready for practical applications because they encounter the following problems: 1) Visual cues are not well defined so it is unclear how to preserve important cues in the transformed gray-scale images; 2) some algorithms have extremely high time cost for computation; and 3) some require human-computer interactions to have a reasonable transformation. To solve or at least reduce these problems, we propose a new algorithm based on a probabilistic graphical model with the assumption that the image is defined over a Markov random field. Thus, color to gray procedure can be regarded as a labeling process to preserve the newly well-defined visual cues of a color image in the transformed gray-scale image. Visual cues are measurements that can be extracted from a color image by a perceiver. They indicate the state of some properties of the image that the perceiver is interested in perceiving. Different people may perceive different cues from the same color image and three cues are defined in this paper, namely, color spatial consistency, image structure information, and color channel perception priority. We cast color to gray as a visual cue preservation procedure based on a probabilistic graphical model and optimize the model based on an integral minimization problem. We apply the new algorithm to both natural color images and artificial pictures, and demonstrate that the proposed approach outperforms representative conventional algorithms in terms of effectiveness and efficiency. In addition, it requires no human-computer interactions.

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Concentrations and carbon isotopic (C-14, C-13) compositions of black carbon (BC) were measured for three sediment cores collected from the Changjiang River estuary and the shelf of the East China Sea. BC concentrations ranged from 0.02 to 0.14 mg/g (dry weight), and accounted for 5% to 26% of the sedimentary total organic carbon (TOC) pool. Among the three sediment cores collected at each site, sediment from the Changjiang River estuary had relatively high BC contents compared with the sediments from the East China Sea shelf, suggesting that the Changjiang River discharge played an important role in the delivery of BC to the coastal region. Radiocarbon measurements indicate that the ages of BC are in the range of 6910 to 12250 years old B. P. (before present), that is in general, 3700 to 9000 years older than the C-14 ages of TOC in the sediments. These variable radiocarbon ages suggest that the BC preserved in the sediments was derived from the products of both biomass fire and fossil fuel combustion, as well as from ancient rock weathering. Based on an isotopic mass balance model, we calculated that fossil fuel combustion contributed most (60%. 80%) of the BC preserved in these sediments and varied with depth and locations. The deposition and burial of this "slow-cycling" BC in the sediments of the East China Sea shelf represent a significant pool of carbon sink and could greatly influence carbon cycling in the region.

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Elemental (TOC, TN, C/N) and stable carbon isotopic (delta(13)C) compositions and n-alkane (nC(16-38)) concentrations were measured for Spartina alterniflora, a C-4 marsh grass, Typha latifolia, a C-3 marsh grass, and three sediment cores collected from middle and upper estuarine sites from the Plum Island salt marshes. Our results indicated that the organic matter preserved in the sediments was highly affected by the marsh plants that dominated the sampling sites. delta(13)C values of organic matter preserved in the upper fresh water site sediment were more negative (-23.0+/-0.3) as affected by the C-3 plants than the values of organic matter preserved in the sediments of middle (-18.9+/-0.8) and mud flat sites (-19.4+/-0.1) as influenced mainly by the C4 marsh plants. The distribution of n-alkanes measured in all sediments showed similar patterns as those determined in the marsh grasses S. alterniflora and T. latifolia, and nC(21) to nC(33) long-chain n-alkanes were the major compounds determined in all sediment samples. The strong odd-to-even carbon numbered n-alkane predominance was found in all three sediments and nC(29) was the most abundant homologue in all samples measured. Both delta(13)C compositions of organic matter and n-alkane distributions in these sediments indicate that the marsh plants could contribute significant amount of organic matter preserved in Plum Island salt marsh sediments. This suggests that salt marshes play an important role in the cycling of nutrients and organic carbon in the estuary and adjacent coastal waters. (C) 2003 Elsevier Ltd. All rights reserved.

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Background: the impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT) in childhood.Methods: the long-term effects of androgen exposure on the fundamental vocal frequency (F0), vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years) and 10 adolescent (13.6 to 17.8 years) female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels.Results: of the 19 subjects, 17 (89%) had been diagnosed with ACT before 4 years of age, 1 (5%) at 8.16 years, and 1 (5%) at 10.75 years. Androgen exposure (2 to 30 months) was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19) of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz) and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz.Conclusions: Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors.

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Objective. To compare the voice performance of children involved in street labor with regular children using perceptual-auditory and acoustic analyses.Methods. A controlled cross-sectional study was carried out on 7- to 10-year-old children of both genders. Children from both groups lived with their families and attended school regularly; however, child labor was evident in one group and not the other. A total of 200 potentially eligible street children, assisted by the Child Labor Elimination Programme (PETI), and 400 regular children were interviewed. Those with any vocal discomfort (106, 53% and 90, 22.5%) had their voices assessed for resonance, pitch, loudness, speech rate, maximum phonation time, and other acoustic measurements.Results. A total of 106 street children (study group [SG]) and 90 regular children (control group [CG]) were evaluated. the SG group demonstrated higher oral and nasal resonance, reduced loudness, a lower pitch, and a slower speech rate than the CG. the maximum phonation time, fundamental frequency, and upper harmonics were higher in the SG than the CG. Jitter and shimmer were higher in the CG than the SG.Conclusion. Using perceptual-auditory and acoustic analyses, we determined that there were differences in voice performance between the two groups, with street children having better quality perceptual and acoustic vocal parameters than regular children. We believe that this is due to the procedures and activities performed by the Child Labor Elimination Program (PETI), which helps children to cope with their living conditions.

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The application of inverse filtering techniques for high-quality singing voice analysis/synthesis is discussed. In the context of source-filter models, inverse filtering provides a noninvasive method to extract the voice source, and thus to study voice quality. Although this approach is widely used in speech synthesis, this is not the case in singing voice. Several studies have proved that inverse filtering techniques fail in the case of singing voice, the reasons being unclear. In order to shed light on this problem, we will consider here an additional feature of singing voice, not present in speech: the vibrato. Vibrato has been traditionally studied by sinusoidal modeling. As an alternative, we will introduce here a novel noninteractive source filter model that incorporates the mechanisms of vibrato generation. This model will also allow the comparison of the results produced by inverse filtering techniques and by sinusoidal modeling, as they apply to singing voice and not to speech. In this way, the limitations of these conventional techniques, described in previous literature, will be explained. Both synthetic signals and singer recordings are used to validate and compare the techniques presented in the paper.

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This volume is devoted to the broad topic of distributed digital preservation, a still-emerging field of practice for the cultural memory arena. Replication and distribution hold out the promise of indefinite preservation of materials without degradation, but establishing effective organizational and technical processes to enable this form of digital preservation is daunting. Institutions need practical examples of how this task can be accomplished in manageable, low-cost ways."--P. [4] of cover

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This research is an exploration of the expression of student voice in Irish post-primary schools and how its affordance could impact on students’ and teachers’ experiences in the classroom, and at whole-school level through a student council. Student voice refers to the inclusion of students in decisions that shape their experiences in classrooms and schools, and is fundamental to a rights-based perspective that facilitates students to have a voice and a say in their education. Student voice is essential to the development of democratic principles, active citizenship, and learning and pedagogy. This qualitative research, based in three post-primary case-study schools, concerns teachers in eighteen classrooms engaging in dialogic consultation with their students over one school year. Teachers considered the students’ commentary and then adjusted their practice. The operation of student councils was also examined through the voices of council members, liaison teachers and school principals. Theorised within socio-cultural (social constructivist), social constructionist and poststructural frames, the complexity of student voice emerges from its conceptualisation and enactment. Affording students a voice in their classroom presented positive findings in the context of relationships, pedagogical change and students’ engagement, participation and achievement. The power and authority of the teacher and discordant student voices, particularly relating to examinations, presented challenges affecting teachers’ practice and students’ expectations. The functional redundancy of the student council as a construct for student voice at whole-school level, and its partial redundancy as a construct to reflect prefigurative democracy and active citizenship also emerge from the research. Current policy initiatives in Irish education situate student voice in pedagogy and as dialogic consultation at classroom and whole-school level. This work endorses the necessity for and benefit of such a positioning with the author further arguing that it should not become the instrumental student voice of data source, accountability and performativity.

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Fungal spoilage of food and feed prevails as a major problem for the food industry. The use antifungal-producing lactic acid bacteria (LAB) may represent a safer, natural alternative to the use of chemical preservatives in foods. A large scale screen was undertaken to identify a variety of LAB with antifungal properties from plant, animal and human sources. A total of 6,720 LAB colonies were isolated and screened for antifungal activity against the indicator Penicillium expansum. 94 broad-spectrum producers were identified through 16S rRNA sequencing with the majority of the population comprising Lactobacillus plantarum isolates. Six broad-spectrum isolates were consequently characterised. Pedicococcus pentosaceous 54 displayed potent anti-mould capabilities in pear, plum and grape models and may represent an ideal candidate for use in the beverage industry. Two antifungal Lb. plantarum isolates were assessed for their technological robustness and potential as biopreservatives in refrigerated foods. Lb. plantarum 16 and 62 displayed high levels of tolerance to freeze-drying, low temperature exposure and high salt concentrations. Both lactobacilli were introduced as supplements into orange juice to retard the growth of the spoilage yeast Rhodotorula mucilaginosa. Furthermore the isolates were applied as adjuncts in yoghurt production to successfully reduce yeast growth. Lb. plantarum 16 proved to be the optimal inhibitor of yeast growth in both food matrices. To date there is limited information available describing the mechanisms behind fungal inhibition by LAB. The effects of concentrated cell-free supernatant (cCFS), derived from Lb. plantarum 16, on the growth of two food-associated moulds was assessed microscopically. cCFS completely inhibited spore, germ tube and hyphal development. A transcriptomic approach was undertaken to determine the impact of antifungal activity on Aspergillus fumigatus Af293. A variety of genes, most notably those involved in cellular metabolism, were found to have their transcription modulated in response to cCFS which is indicative of global cellular shutdown. This study provides the first insights into the molecular targets of antifungal compounds produced by LAB. The genome sequence of the steep water isolate Lb. plantarum 16 was determined. The complete genome of Lb. plantarum16 consists of a single circular chromosome of 3,044,738 base pairs with an average G+C content of 44.74 % in addition to eight plasmids. The genome represents the smallest of this species to date while harbouring the largest plasmid complement. Some features of particular interest include the presence of two prophages, an interrupted plantaricin cluster and a chromosomal and plasmid encoded polysaccharide cluster. The sequence presented here provides a suitable platform for future studies elucidating the mechanisms governing antifungal production.

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Cryopreservation of ovarian tissue is now offered as an experimental procedure to preserve the fertility of young patients with a high risk for premature ovarian failure resulting from cancer therapy. This is the only available option to preserve the fertility of prepubertal patients treated with gonadotoxic chemotherapy. At present, thousands of patients all over the world have undergone this procedure with the hope of later restoring their fertility. Although the efficiency of the transplantation of cryopreserved ovarian tissue to restore ovarian function has been established, reports of pregnancy are still very scarce. Here, we describe the second published full-term spontaneous pregnancy after an orthotopic and heterotopic transplantation of cryopreserved ovarian tissue in a 31-year-old woman previously treated by conditioning therapy for bone marrow transplantation for Hodgkin's disease. This birth gives compelling evidence for the graft origin of the gamete and confirms the efficacy of ovarian tissue transplantation in restoring human natural fertility after oncological treatment. This case report stresses the importance of proposing the ovarian tissue cryopreservation procedure to all young patients who require potentially sterilizing treatment, with all alternative options to preserve fertility being duly taken into consideration.

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Gabriel Urbain Fauré lived during one of the most exciting times in music history. Spanning a life of 79 years (1845-1924), he lived through the height of Romanticism and the experimental avant-garde techniques of the early 20th century. In Fauré's music, one can find traces of Chopin, Liszt, Mendelssohn, Debussy and Poulenc. One can even argue that Fauré presages Skryabin and Shostakovich. The late works of Gabriel Fauré, chiefly those composed after 1892, testify to the argument that Fauré holds an important position in the shift from tonal to atonal composition and should be counted among such transitional composers as Gustav Mahler, Claude Debussy, Erik Satie, Richard Strauss, and Ferruccio Busoni. Fauré's unique way of fashioning harmonic impetus of almost purely linear means, resulting in a synthesis of harmonic and melodic devices, led me to craft the term mélodoharmonique. This term refers to a contrapuntally motivated technique of composition, particularly in a secondary layer of musical texture, in which a component of harmonic progression (i.e. arpeggiation, broken chord, etc.) is fused with linear motivic or thematic development. This dissertation seeks to bring to public attention through exploration in lecture and recital format, certain works of Gabriel Fauré, written after 1892. The repertoire will be selected from works for solo piano and piano in collaboration with violin, violoncello, and voice, which support the notion of Fauré as a modernist deserving larger recognition for his influence in the transition to atonal music. The recital repertoire includes the following--Song Cycles: La bonne chanson, opus 61; La chanson d'Ève, opus 95; Le jardin clos, opus 106; Mirages, opus 113; L'horizon chimérique, opus 118; Piano Works: Prelude in G minor opus 103, No. 3; Prelude in E minor opus 103, No. 9; Eleventh Nocturne, opus 104, No.1; Thirteenth Nocturne, opus 119; Chamber Works: Second Violin Sonata, opus 108; First Violoncello Sonata, opus 109; Second Violoncello Sonata, opus 117.

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In 1937 Lisa Sergio, "The Golden Voice" of fascist broadcasting from Rome, fled Italy for the United States. Though her mother was American, Sergio was classified as an enemy alien once the United States entered World War II. Yet Sergio became a U.S. citizen in 1944 and built a successful career in radio, working first at NBC and then WQXR in New York City in the days when women's voices were not thought to be appropriate for news or "serious" programming. When she was blacklisted as a communist in the early 1950s, Sergio compensated for the loss of radio employment by becoming principally an author and lecturer in Washington, D.C., until her death in 1989. This dissertation, based on her personal papers, is the first study of Sergio's American mass communication career. It points out the personal, political and social obstacles she faced as a woman in her 52-year career as a commentator on varied aspects of world affairs, religion and feminism. This study includes an examination of the FBI investigations of Sergio and the anti-communist campaigns conducted against her. It concludes that Sergio's success as a public communicator was predicated on both her unusual talents and her ability to transform her public image to reflect ideal American values of womanhood in shifting political climates.