Acoustic analysis of speech through a hearing aid: perceptual effects of changes with two-channel compression

Compression amplification significantly alters the acoustic speech signal in comparison to linear amplification. The central hypothesis of the present study was that the compression settings of a two-channel aid that best preserved the acoustic properties of speech compared to linear amplification would yield the best perceptual results, and that the compression settings that most altered the acoustic properties of speech compared to linear would yield significantly poorer speech perception. On the basis of initial acoustic analysis of the test stimuli recorded through a hearing aid, two different compression amplification settings were chosen for the perceptual study. Participants were 74 adults with mild to moderate sensorineural hearing impairment. Overall, the speech perception results supported the hypothesis. A further aim of the study was to determine if variation in participants' speech perception with compression amplification (compared to linear amplification) could be explained by the individual characteristics of age, degree of loss, dynamic range, temporal resolution, and frequency selectivity; however, no significant relationships were found.

A naturally selected dimorphism within the HLA-B44 supertype alters class I structure, peptide repertoire, and T cell recognition

HLA-B*4402 and B*4403 are naturally occurring MHC class I alleles that are both found at a hi,,h frequency in all human populations, and vet they only differ by one residue on the alpha2 helix (B*4402 Aspl56-->B*4403 Leu156) CTLs discriminate between HLA-B*4402 and B*4403, and these allotypes stimulate strong mutual allogeneic responses reflecting their known barrier to hemopoeitic stem cell transplantation. Although HLA-B*4402 and B*4403 share >95% of their peptide repertoire, B*4403 presents more unique peptides than B*4402, consistent with the stronger T cell alloreactivity observed toward B*4403 compared with B*4402. Crystal structures of B*4402 and B*4403 show how the polymorphisin at position 156 is completely buried and yet alters both the peptide and the heavy chain conformation, relaxing ligand selection by B*4403 compared with B*4402. Thus, the polymorphism between HLA-B*4402 and B 4403 modifies both peptide repertoire and T cell recognition, and is reflected lit the paradoxically powerful alloreactivity that occurs across this minimal mismatch. The findings suggest that these closely related class I genes are maintained lit diverse human populations through their differential impact on the selection of peptide ligands and the T cell repertoire.

Promiscuous CTL recognition of viral epitopes on multiple human leukocyte antigens: Biological validation of the proposed HLA A24 supertype

Multiple HLA class I alleles can bind peptides with common sequence motifs due to structural similarities in the peptide binding cleft, and these groups of alleles have been classified into supertypes. Nine major HLA supertypes have been proposed, including an A24 supertype that includes A*2301, A*2402, and A*3001. Evidence for this A24 supertype is limited to HLA sequence homology and/or similarity in peptide binding motifs for the alleles. To investigate the immunological relevance of this proposed supertype, we have examined two viral epitopes (from EBV and CMV) initially defined as HLA-A*2301-binding peptides. The data clearly demonstrate that each peptide could be recognized by CTL clones in the context of A*2301 or A*2402; thus validating the inclusion of these three alleles within an A24 supertype. Furthermore, CTL responses to the EBV epitope were detectable in both A*2301(+) and A*2402(+) individuals who had been previously exposed to this virus. These data substantiate the biological relevance of the A24 supertype, and the identification of viral epitopes with the capacity to bind promiscuously across this supertype could aid efforts to develop CTL-based vaccines or immunotherapy. The degeneracy in HLA restriction displayed by some T cells in this study also suggests that the dogma of self-MHC restriction needs some refinement to accommodate foreign peptide recognition in the context of multiple supertype alleles.

Voice and speech characteristics and vocal hygiene in novice and professional voice broadcast journalists

Knowledge of differences in voice and speech characteristics between novice and professional broadcasters is essential for effective education of broadcast journalism students. Because newsreaders rely on optimal voice production, information pertaining to vocal hygiene is also important. The first aim of this study was to compare the voice and speech characteristics of professional newsreaders, student newsreaders and control participants. The second aim was to compare the awareness and use of vocal hygiene across these groups. Professional radio newsreaders, broadcast journalism students and two matched control groups were included in the study. Each participant recorded a news bulletin and completed a questionnaire on vocal hygiene. Data analysis of the recording included objective analysis and perceptual ratings by a panel of three judges. Significant student-professional differences were found. Compared to both the students and the control groups, the professional newsreaders had greater variation in speaking fundamental frequency, a faster rate of speech, fewer pronunciation errors and higher perceptual ratings on vocal quality, emphasis, continuity, phrasing and style of newsreading. Female professional newsreaders had a higher speaking fundamental frequency than both their control participants and the student newsreaders. Comparison of vocal hygiene awareness revealed few significant differences between any of the groups.

Mitigated directness in Honglou meng: directive speech acts and politeness in eighteenth century Chinese

This paper is situated within a theoretical discussion that asserts a positive correlation between indirectness and politeness, and uses these claims as a springboard for an examination of polite ways of issuing directives in eighteenth century Chinese. On the basis of an analysis of directive speech acts from dialogue in the novel Honglou meng, it argues that the concept of indirectness, as it applies to the illocutionary transparency of individual speech acts, has no particular value in the culture and language of eighteenth century Chinese men. It is found that other linguistic devices such as particles, the reduplication of verbs, terms of address, and the presence and sequencing of supportive moves are far more significant to the communication of politeness. The findings suggest a need to rethink current theoretical positions on this subject and move beyond the analysis of individual speech acts to examine the role discourse structure and management play in the enactment of politeness. (C) 2002 Elsevier Science B.V. All rights reserved.

The basal ganglia and semantic engagement: Potential insights from semantic priming in individuals with subcortical vascular lesions, Parkinson's disease, and cortical lesions

The impact of basal ganglia dysfunction on semantic processing was investigated by comparing the performance of individuals with nonthalamic subcortical (NS) vascular lesions, Parkinson's disease (PD), cortical lesions, and matched controls on a semantic priming task. Unequibiased lexical ambiguity primes were used in auditory prime-target pairs comprising 4 critical conditions; dominant related (e.g., bank-money), subordinate related (e.g., bank-river), dominant unrelated (e.g.,foot-money) and subordinate unrelated (e.g., bat-river). Participants made speeded lexical decisions (word/nonword) on targets using a go-no-go response. When a short prime-target interstimulus interval (ISI) of 200 ins was employed, all groups demonstrated priming for dominant and subordinate conditions, indicating nonselective meaning facilitation and intact automatic lexical processing. Differences emerged at the long ISI (1250 ms), where control and cortical lesion participants evidenced selective facilitation of the dominant meaning, whereas NS and PD groups demonstrated a protracted period of nonselective meaning facilitation. This finding suggests a circumscribed deficit in the selective attentional engagement of the semantic network on the basis of meaning frequency, possibly implicating a disturbance of frontal-subcortical systems influencing inhibitory semantic mechanisms.

Cidade-paisagem : novas perspectivas sobre a preservação da paisagem urbana no Brasil

The edification of the landscape in the scientific and social field, in speech as in the method, is taken in this study as a complex process, from which were developed relationships of dominance on the perception of space, which persist strongly consolidated, since the genesis of the conceptual practice till its actual praxis. Historically, the landscape studies took place slowly, immersed in many questions, in face of the multiplicity of meanings that the concept offers. In the psyche, the notion of landscape is present since a long time ago, as an unconscious human being practice, even before any ideological hypothesis formulation. However its materialization in the social conscious will come only from painting, and specially with the perspective, through the technicity of the view, at first wandering the infinity, now ordained in a frame‟. Since then, the landscape is perceived according to the order of the view, as the equivalent of nature and beauty, assuming at the same time, an important symbolic value, since it is linked to mnemonic and subjective processes that the being build with the territory. The domain on this space-cognitive experience, characteristic of the contemporary, consolidates in the social imaginary, building consensus on the landscape, whose aesthetic references make a cultural appeal, very pertinent to the actual capitalist dynamics of production the space worldwide, mainly of the spectacle and commodification of cities promoted by the city marketing. In Brazil, this consensual ideology of the landscape surpass the social imaginary and also dominates the political imaginary, whereas the main instrument for preserving the landscape, Decree-law 25, from November 30, 1937, and its limit to those of exceptional value or remarkable feature. The analysis of the processes for putting under governmental trust for inscription of goods by the landscape value, reveals the dominant, if not exclusive, adoption of selection criteria related to aesthetic aspects. Abstain, therefore, from what the nation considers patrimony , other landscapes that, besides not having, at first, remarkable aesthetic value, play a crucial role as an inheritance from ancestor relations between man and space and pre- existing condition for the same present and future relations. From this historical background, the research seeks to transfer into contemporaneity, the ideological analysis of the concept and its relation with the building of the landscape in the collective imaginary, in order to recognize, in current practices to landscape preservation, as much this genesis, rooted in aesthetics, remains strongly consolidated, feeding the current dynamics of consumption and commodification of the city. Therefore, as preliminary conclusion, one can state that the identification of landscapes of different value, especially aesthetic, maintains and intensify the treatment of the city as an object, a standard‟ commodity to be sold / traded on the world market, in detriment of its recognition as a dynamic process that, even though inserted in the global context, develops specificifities and peculiarities, inherent to the production of space, as Lefebvre preconizes, that is, to the production of life, social product , as characteristic, dissent generator

Práticas de comunicação audiovisual participativa: apresentação de um caso de estudo no contexto das instituições culturais

Nesta comunicação apresentaremos as metodologias e conclusões previstas da primeira fase do trabalho de construção de narrativas audiovisuais participativas relacionadas com o projeto “Manobras no Porto”, que irá servir de caso de estudo para o projeto de investigação intitulado: “The Museum of All: Práticas de Comunicação Institucional num Mundo de Redes Participativas”. Recorrendo a técnicas de observação participante, nesta primeira fase, o objectivo é mapear o posicionamento dos parceiros do projeto em estudo e identificar as suas ações de dinamização cultural, recolher informações sobre as problemáticas sociais, económicas e culturais da zona de intervenção do projeto e auscultar os públicos intervenientes sobre as prioridades nos seus quotidianos e vivências. Posteriormente, passaremos a uma fase de proposição, com o objectivo de analisar contextos de cooperação, participação e envolvimento das comunidades na criação colectiva de novas mensagens e narrativas, através da implementação de um conjunto de exercícios audiovisuais participativos.

Espectador Activo: Comunicação audiovisual institucional num mundo de redes participativas

Once delighted by the moving image advent as a new method of realistically presenting reality, the viewer has been reposition himself towards the audiovisual contents he consumes, as he is given the opportunity to create and share his own perspective of that reality. We are living in a new technological setting, governed mainly by factors of interactivity, digital systems and technological convergence. The research project that we will present in this paper focuses on the subject of participatory media and the way cultural institutions are increasingly facing the inevitability of a profound revision of their traditional parameters of unidirectional communication, given the increasing availability of tools for audiovisual production as well as the diversity of networked communication contexts. The Serralves Foundation with its Museum of Contemporary Art, in Porto, Portugal, was the subject of a fi rst study of an empirical nature: a series of audiovisual objects were developed, in order to generate material for analysis and proposition. In this new stage of the project, our aim is to identify new procedures and practices that may be effectively implemented within the institutional universe. We intend to propose effi cient audiovisual communication contexts, including the maximizing of the relationship between institutions and audiences regarding dimensions that are traditionally outside the institutional radar: identity, narrative and affection. The project is currently in the process of surveying and categorization, with the aim of producing a map of different vocations and positions of the various institutions in regards to the aforementioned issues, which require participatory communication.

Computer-aided recognition of dental implants in X-ray images

Dental implant recognition in patients without available records is a time-consuming and not straightforward task. The traditional method is a complete user-dependent process, where the expert compares a 2D X-ray image of the dental implant with a generic database. Due to the high number of implants available and the similarity between them, automatic/semi-automatic frameworks to aide implant model detection are essential. In this study, a novel computer-aided framework for dental implant recognition is suggested. The proposed method relies on image processing concepts, namely: (i) a segmentation strategy for semi-automatic implant delineation; and (ii) a machine learning approach for implant model recognition. Although the segmentation technique is the main focus of the current study, preliminary details of the machine learning approach are also reported. Two different scenarios are used to validate the framework: (1) comparison of the semi-automatic contours against implant’s manual contours of 125 X-ray images; and (2) classification of 11 known implants using a large reference database of 601 implants. Regarding experiment 1, 0.97±0.01, 2.24±0.85 pixels and 11.12±6 pixels of dice metric, mean absolute distance and Hausdorff distance were obtained, respectively. In experiment 2, 91% of the implants were successfully recognized while reducing the reference database to 5% of its original size. Overall, the segmentation technique achieved accurate implant contours. Although the preliminary classification results prove the concept of the current work, more features and an extended database should be used in a future work.

Maternal Recognition of Pregnancy in the Mare : a mini review

Nos equinos, um grande número de eventos das fases iniciais do desenvolvimento embrionário são únicos e distintos daqueles que se verificam em outras espécies, incluindo os críticos mas pouco esclarecidos mecanismos de reconhecimento materno da gestação. Este processo fisiológico, através do qual o concepto sinaliza a sua presença ao organismo materno assegurando a manutenção do corpo lúteo (CL) primário e, consequentemente, dos níveis de progesterona necessários à sobrevivência e desenvolvimento do embrião, está pouco esclarecido. De facto, ainda não é claro qual o sinal embrionário primário que assegura a manutenção do CL nos equinos e, apesar do número de potenciais factores que contribuem para o reconhecimento e manutenção da gestação não parar de crescer, nenhum é capaz por si só de satisfazer todos os critérios que caracterizam um factor anti-luteolítico ou luteostático. Por outro lado, é geralmente aceite o conceito de que o reconhecimento materno da gestação é um fenómeno fisiológico de extrema importância e que qualquer falha, quer no envio quer na recepção do sinal apropriado, pode levar a morte embrionária. De facto, a perda de gestações durante ou à volta do espaço de tempo em que ocorre o reconhecimento materno da gestação (i.e dias 10-16 após a ovulação) é comum mas imprevisível (e, portanto, difícil de controlar e prevenir) na prática clínica, sendo uma causa de grandes perdas económicas.

Arquivo documental: relativo à Lei do Cinema e do Audiovisual, criação do FICA e transformação do ICAM em ICA (2003-2007)

O projecto “Principais tendências no cinema português contemporâneo” nasceu no Departamento de Cinema da ESTC, com o objectivo de desenvolver investigação especializada a partir de um núcleo formado por alunos da Licenciatura em Cinema e do Mestrado em Desenvolvimento de Projecto Cinematográfico, a que se juntaram professores-investigadores membros do CIAC e convidados. O que agora se divulga corresponde a dois anos e meio de trabalho desenvolvido pela equipa de investigação, entre Abril de 2009 e Novembro de 2011. Dada a forma que ele foi adquirindo, preferimos renomeá-lo, para efeitos de divulgação, “Novas & velhas tendências no cinema português contemporâneo”.

Tuning Iris Recognition for Noisy Images

The use of iris recognition for human authentication has been spreading in the past years. Daugman has proposed a method for iris recognition, composed by four stages: segmentation, normalization, feature extraction, and matching. In this paper we propose some modifications and extensions to Daugman's method to cope with noisy images. These modifications are proposed after a study of images of CASIA and UBIRIS databases. The major modification is on the computationally demanding segmentation stage, for which we propose a faster and equally accurate template matching approach. The extensions on the algorithm address the important issue of pre-processing that depends on the image database, being mandatory when we have a non infra-red camera, like a typical WebCam. For this scenario, we propose methods for reflection removal and pupil enhancement and isolation. The tests, carried out by our C# application on grayscale CASIA and UBIRIS images show that the template matching segmentation method is more accurate and faster than the previous one, for noisy images. The proposed algorithms are found to be efficient and necessary when we deal with non infra-red images and non uniform illumination.

Image and color recognition using amorphous silicon p-i-n photodiodes

Large area hydrogenated amorphous silicon single and stacked p-i-n structures with low conductivity doped layers are proposed as monochrome and color image sensors. The layers of the structures are based on amorphous silicon alloys (a-Si(x)C(1-x):H). The current-voltage characteristics and the spectral sensitivity under different bias conditions are analyzed. The output characteristics are evaluated under different read-out voltages and scanner wavelengths. To extract information on image shape, intensity and color, a modulated light beam scans the sensor active area at three appropriate bias voltages and the photoresponse in each scanning position ("sub-pixel") is recorded. The investigation of the sensor output under different scanner wavelengths and varying electrical bias reveals that the response can be tuned, thus enabling color separation. The operation of the sensor is exemplified and supported by a numerical simulation.