Background: There are 850,000 people living with dementia in the UK; this number includes Deaf people who use British Sign Language, but little is known of their experience or how services might be improved to support them and their carers, who are often also Deaf. Deaf people are routinely excluded from reports on linguistic/cultural minorities and dementia because their status, as such, is not recognised. They are very different from the much larger population of older people who lose their hearing and may also have dementia. Aims and Objectives: i) To explore the everyday experiences of living with dementia from the perspectives of Deaf BSL users with dementia and their care partners; ii) To explore the general Deaf community's knowledge and understanding of dementia, its symptoms and impact on everyday life. Method: Three focus groups were held with a total of 26 Deaf BSL users, who did not have dementia, to gauge their knowledge about dementia and where they might go for support. Four Deaf BSL users living with dementia with five care partners took part in two semi-structured interviews 6-8 weeks apart. Data were analysed using thematic analysis, storied stories and narrative analysis. All data were collected in BSL by a Deaf researcher. ResultsLack of access to information and support in BSL impeded early recognition of symptoms, access to diagnosis, and support within the Deaf community. Personal narratives revealed Deaf people's resilience while living with dementia. Narratives challenged key concerns of personhood, citizenship and embodiment from a different perspective because Deaf people are not usually regarded as full citizens and their capacity is routinely challenged regardless of dementia. Furthermore, embodiment of communication and language is a life-long experience, not residual adaptation. Visual strategies to support agency were also documented. Conclusions: The Deaf community needs provision of accessible and understandable information about dementia in BSL. Mainstream dementia support services should review their accessibility of effective support for Deaf BSL users who have been diagnosed with dementia and their families. However, Deaf people with dementia remain resilient and positive about their everyday lives with the support of their familial relationships.

This was a project joint between the University of Dundee and The James Hutton Institute where both parties were interested in further understanding the interactions between plant host proteins and pathogen effector proteins. An objective of this thesis was to determine the host target of the Phytophthora infestans effector PiAVR2 and the means by which this avirulence protein is recognised by the potato resistance protein, R2. Prior to this PhD, forward genetic studies identified three RXLR effector encoding genes within the AVR2 locus. By use of transient co-expression with the resistance gene R2 it was determined which of these genes was PiAVR2. A virulent form of PiAVR2, named PiAVR2-like, was found within isolates of P. infestans. Isolates which only express PiAVR2-like are virulent on potato cultivars expressing R2. Isolates which express both forms, or only the PiAVR2 form, are avirulent on cultivars expressing R2. This suggests that expressing only PiAVR2-like is key to the virulence of the pathogen on R2 expressing cultivars. There are 10 known orthologues of R2 which all recognise PiAVR2. However none can recognise PiAVR2-like. The characterisation of the means by which P. infestans overcomes R2 resistance has provided a strategy, based on identifying R genes that recognise PiAVR2-like, to provide durable late blight disease resistance. It was also discovered that both PiAVR2 and PiAVR2-like physically interact with the same host target proteins, BSL1, BSL2a and BSL2b. The BSLs are part of a family of Kelch repeat containing Ser/Thr phosphatases which function as activators of the brassinosteroid signal transduction pathway. It was shown that silencing of the BSL1 and BSL2a genes within plants results in the attenuation of PiAVR2 recognition by R2. In the case of BSL1 it was further shown that an interaction between R2 and BSL1 only occurs in the presence of PiAVR2. This implies that R2 recognises PiAVR2 by an indirect mechanism, utilising either the Guard or Decoy Hypotheses, and that BSL1 is essential for this recognition. This is the first reported demonstration of indirect recognition of an intracellular eukaryotic plant pathogen effector protein.

No description available.

<p>Bacillus anthracis is a risk class III organism and needs to be handled inside a biosafety level 3-laboratory. A major problem when working with airborne, spore-forming bacteria like B. anthracis are the hazardous aerosols created when using an automated DNA-extraction method to prepare samples suspected to contain the organism. This study has therefore evaluated the possibility of enclosing a DNA-extraction-robot inside an air tight container (glove box). A prototype of a class III safety cabinet (also known as a glove box) was designed and built to enclose a BioRobot EZ1 from Qiagen. The purpose of this prototype was to evaluate the measurements needed to and also the feasibility of working with the robot inside the cabinet. During the manual DNA-extractions, there was some contamination found on the glove box gloves, probably due to the significantly lowered dexterity that was seen with the thick gloves. The enclosing of the robot revealed no obstacles as the machine was very easy to operate. In addition, protocols have been created for the operation of a transportable class III safety cabinet from Germfree available at SVA. The protocols include the different pressure tests that needed before every experiment take place and also decontamination steps before and after each run. Bacillus cereus was used as a model organism for different DNA-extractions, i.e. automated and manual extractions. The extracted DNA was analysed by real-time polymerase chain reaction (PCR). DNA was also extracted and analysed from B. cereus-spores. When using a manual DNA-extraction kit, B. cereus-DNA was detected at the femtogram level, i.e. 10-15 g DNA / PCR. When using the automated BioRobot EZ1, detection level was found to be at 10-16 g DNA / PCR. The PCR-efficiency for the manual kit was 89-90 % for all samples, whereas with the EZ1, efficiency was 99 %, showing the strengths of the magnetic bead separation used by the machine. A novel PCR-machine, the AlphaHelix QuanTyper™, was evaluated and compared to an ABI 7500 with regards to efficiency, speed and consistency. The QuanTyper™ was found to be superior in ramping speeds, performing a 40-cycle real-time PCR-run with melting point analysis in only 14 minutes. The fastest run accomplished on the ABI 7500 took 1 h 40 min. A ready made master mix for PCR was used for most tests (Platinum® SYBR® Green qPCR SuperMix-UDG), but faster and more robust enzymes are available and further studies need to be performed on the QuanTyper™ to fully evaluate the platform. Three target genes in Bacillus anthracis-DNA were analysed in only 38 minutes with efficiencies between 96-104 % for the virulence plasmids and detection at femtogram amount of DNA. This master thesis has addressed rapid pathogen-detection with automated DNA-extraction and novel PCR-technology, coupled with a strong biosafety aspect. The thesis will hopefully contribute to the surprisingly small area of biosafety and safety cabinet research.</p>

The aim of this work is design of system for wireless data collection from energy meters. The work shows issues of smart metering and explains meters communication. There is designed and described concept of the system composed of RF modules connected to data concentrator. Designed RF module uses SoC radio CC430F5137 and it is connected to a data concentrator via RS485 bus. For the purposes of communication as well as firmware update, the communication protocol is designed. In the next part the work focuses on design and creation of RF module frmware, bootloader for RF module and software application for energy meter data processing.

Bacillus anthracis is a risk class III organism and needs to be handled inside a biosafety level 3-laboratory. A major problem when working with airborne, spore-forming bacteria like B. anthracis are the hazardous aerosols created when using an automated DNA-extraction method to prepare samples suspected to contain the organism. This study has therefore evaluated the possibility of enclosing a DNA-extraction-robot inside an air tight container (glove box). A prototype of a class III safety cabinet (also known as a glove box) was designed and built to enclose a BioRobot EZ1 from Qiagen. The purpose of this prototype was to evaluate the measurements needed to and also the feasibility of working with the robot inside the cabinet. During the manual DNA-extractions, there was some contamination found on the glove box gloves, probably due to the significantly lowered dexterity that was seen with the thick gloves. The enclosing of the robot revealed no obstacles as the machine was very easy to operate. In addition, protocols have been created for the operation of a transportable class III safety cabinet from Germfree available at SVA. The protocols include the different pressure tests that needed before every experiment take place and also decontamination steps before and after each run. Bacillus cereus was used as a model organism for different DNA-extractions, i.e. automated and manual extractions. The extracted DNA was analysed by real-time polymerase chain reaction (PCR). DNA was also extracted and analysed from B. cereus-spores. When using a manual DNA-extraction kit, B. cereus-DNA was detected at the femtogram level, i.e. 10-15 g DNA / PCR. When using the automated BioRobot EZ1, detection level was found to be at 10-16 g DNA / PCR. The PCR-efficiency for the manual kit was 89-90 % for all samples, whereas with the EZ1, efficiency was 99 %, showing the strengths of the magnetic bead separation used by the machine. A novel PCR-machine, the AlphaHelix QuanTyper™, was evaluated and compared to an ABI 7500 with regards to efficiency, speed and consistency. The QuanTyper™ was found to be superior in ramping speeds, performing a 40-cycle real-time PCR-run with melting point analysis in only 14 minutes. The fastest run accomplished on the ABI 7500 took 1 h 40 min. A ready made master mix for PCR was used for most tests (Platinum® SYBR® Green qPCR SuperMix-UDG), but faster and more robust enzymes are available and further studies need to be performed on the QuanTyper™ to fully evaluate the platform. Three target genes in Bacillus anthracis-DNA were analysed in only 38 minutes with efficiencies between 96-104 % for the virulence plasmids and detection at femtogram amount of DNA. This master thesis has addressed rapid pathogen-detection with automated DNA-extraction and novel PCR-technology, coupled with a strong biosafety aspect. The thesis will hopefully contribute to the surprisingly small area of biosafety and safety cabinet research.

O reconhecimento de língua de sinais é uma importante área de pesquisa que tem como objetivo atenuar os obstáculos impostos no dia a dia das pessoas surdas e/ou com deficiência auditiva e aumentar a integração destas pessoas na sociedade majoritariamente ouvinte em que vivemos. Baseado nisso, esta dissertação de mestrado propõe o desenvolvimento de um sistema de informação para o reconhecimento automático de Língua Brasileira de Sinais (LIBRAS), que tem como objetivo simplificar a comunicação entre surdos conversando em LIBRAS e ouvintes que não conheçam esta língua de sinais. O reconhecimento é realizado por meio do processamento de sequências de imagens digitais (vídeos) de pessoas se comunicando em LIBRAS, sem o uso de luvas coloridas e/ou luvas de dados e sensores ou a exigência de gravações de alta qualidade em laboratórios com ambientes controlados, focando em sinais que utilizam apenas as mãos. Dada a grande dificuldade de criação de um sistema com este propósito, foi utilizada uma abordagem para o seu desenvolvimento por meio da divisão em etapas. Considera-se que todas as etapas do sistema proposto são contribuições para trabalhos futuros da área de reconhecimento de sinais, além de poderem contribuir para outros tipos de trabalhos que envolvam processamento de imagens, segmentação de pele humana, rastreamento de objetos, entre outros. Para atingir o objetivo proposto foram desenvolvidas uma ferramenta para segmentar sequências de imagens relacionadas à LIBRAS e uma ferramenta para identificar sinais dinâmicos nas sequências de imagens relacionadas à LIBRAS e traduzi-los para o português. Além disso, também foi construído um banco de imagens de 30 palavras básicas escolhidas por uma especialista em LIBRAS, sem a utilização de luvas coloridas, laboratórios com ambientes controlados e/ou imposição de exigências na vestimenta dos indivíduos que executaram os sinais. O segmentador implementado e utilizado neste trabalho atingiu uma taxa média de acurácia de 99,02% e um índice overlap de 0,61, a partir de um conjunto de 180 frames pré-processados extraídos de 18 vídeos gravados para a construção do banco de imagens. O algoritmo foi capaz de segmentar pouco mais de 70% das amostras. Quanto à acurácia para o reconhecimento das palavras, o sistema proposto atingiu 100% de acerto para reconhecer as 422 amostras de palavras do banco de imagens construído, as quais foram segmentadas a partir da combinação da técnica de distância de edição e um esquema de votação com um classificador binário para realizar o reconhecimento, atingindo assim, o objetivo proposto neste trabalho com êxito. / The recognition of sign language is an important research area that aims to mitigate the obstacles in the daily lives of people who are deaf and/or hard of hearing and increase their integration in the majority hearing society in which we live. Based on this, this dissertation proposes the development of an information system for automatic recognition of Brazilian Sign Language (BSL), which aims to simplify the communication between deaf talking in BSL and listeners who do not know this sign language. The recognition is accomplished through the processing of digital image sequences (videos) of people communicating in BSL without the use of colored gloves and/or data gloves and sensors or the requirement of high quality recordings in laboratories with controlled environments focusing on signals using only the hands. Given the great difficulty of setting up a system for this purpose, an approach divided in several stages was used. It considers that all stages of the proposed system are contributions for future works of sign recognition area, and can contribute to other types of works involving image processing, human skin segmentation, object tracking, among others. To achieve this purpose we developed a tool to segment sequences of images related to BSL and a tool for identifying dynamic signals in the sequences of images related to the BSL and translate them into portuguese. Moreover, it was also built an image bank of 30 basic words chosen by a BSL expert without the use of colored gloves, laboratory-controlled environments and/or making of the dress of individuals who performed the signs. The segmentation algorithm implemented and used in this study had a average accuracy rate of 99.02% and an overlap of 0.61, from a set of 180 preprocessed frames extracted from 18 videos recorded for the construction of database. The segmentation algorithm was able to target more than 70% of the samples. Regarding the accuracy for recognizing words, the proposed system reached 100% accuracy to recognize the 422 samples from the database constructed (the ones that were segmented), using a combination of the edit distance technique and a voting scheme with a binary classifier to carry out the recognition, thus reaching the purpose proposed in this work successfully.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-08-01T15:14:21Z No. of bitstreams: 2 Dissertação - Elizabel Bernardes Atayde Ribeiro - 2015.pdf: 4613309 bytes, checksum: 0570d271d9f04f5914e1c45cd0b23569 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-08-01T15:15:06Z (GMT) No. of bitstreams: 2 Dissertação - Elizabel Bernardes Atayde Ribeiro - 2015.pdf: 4613309 bytes, checksum: 0570d271d9f04f5914e1c45cd0b23569 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-08-01T15:15:06Z (GMT). No. of bitstreams: 2 Dissertação - Elizabel Bernardes Atayde Ribeiro - 2015.pdf: 4613309 bytes, checksum: 0570d271d9f04f5914e1c45cd0b23569 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-09-28 / This paper aims to reflect on the sociolinguistic situation of the deaf in the field of bilingual education in a perspective of inclusive education. The discussion of a specific and differentiated education with the participation of deaf teacher by the pedagogical practices, the program of Goiânia´s city specialized education care whose name is known “Atendimento Educacional Especializado” (AEE) involves sociopolitical and linguistic issues, which may favor or not recognition of the deaf subject of linguistic differentiation, community participation, and Brazilian Sign Language (BSL), also known LIBRAS in Brazil, as the locus of enunciation. This research focused on the teaching of BSL, describing the actual situation of teaching and learning for the deaf, having LIBRAS (BSL) as the shared language of instruction in deaf students and teachers interaction in dialogic processes for teaching. In this sense, we seek to highlight elements of teaching practice that may favor the institutionalization of new language policies of bilingual education, not only to accessibility language(s), but the knowledge, goods and services in quality education in according to the specifics of the subject deaf, and the LIBRAS (BSL), the language base for the acquisition of other knowledge. We have analyzed the proposal and the reality of Inclusive Education Program for the Deaf in Bilingual perspective - PROSURDO, the Public Network of Goiania Education, intended to intervene in the teaching and learning through language planning and thereby promote inclusive teaching situations through meaningful learning to deaf students with teachers deaf. / Esta dissertação tem por objetivo refletir sobre a situação sociolinguística dos surdos no campo da educação bilíngue, numa perspectiva da educação inclusiva. A discussão sobre uma educação específica e diferenciada tem participação do professor surdo nas práticas pedagógicas propostas por um programa desenvolvido na rede municipal de educação de Goiânia e envolve questões sociopolíticas e linguísticas, que podem favorecer ou não o reconhecimento do SURDO, sujeito de diferenciação linguística, comunidade de participação, e a LIBRAS, como o lócus de enunciação. Esta pesquisa focalizou o ensino da LIBRAS e em LIBRAS, descrevendo as situações reais de ensino e aprendizagem com surdos, e LIBRAS, a língua de comunicação através de processos dialógicos para o ensino entre professor surdo-educandos surdos. Neste sentido, buscamos destacar elementos dessa prática de ensino que podem favorecer à institucionalização de novas políticas linguísticas de ensino bilíngue, não apenas à acessibilidade à (s) língua (s), mas aos conhecimentos, bens e serviços, na escolarização do surdo, de acordo com seu universo, sendo, a LIBRAS, a língua base para a aquisição dos demais saberes. Analisamos a proposta e a realidade do Programa de Educação Inclusiva para Surdos na perspectiva Bilíngue da Rede Municipal de Ensino de Goiânia, cuja intenção primordial seria intervir na situação ensino e aprendizagem por meio de planejamento linguístico e, assim, promover diálogos interativos numa aprendizagem significativa entre interlocutores surdos e ouvintes bilíngues.

O reconhecimento de língua de sinais é uma importante área de pesquisa que tem como objetivo atenuar os obstáculos impostos no dia a dia das pessoas surdas e/ou com deficiência auditiva e aumentar a integração destas pessoas na sociedade majoritariamente ouvinte em que vivemos. Baseado nisso, esta dissertação de mestrado propõe o desenvolvimento de um sistema de informação para o reconhecimento automático de Língua Brasileira de Sinais (LIBRAS), que tem como objetivo simplificar a comunicação entre surdos conversando em LIBRAS e ouvintes que não conheçam esta língua de sinais. O reconhecimento é realizado por meio do processamento de sequências de imagens digitais (vídeos) de pessoas se comunicando em LIBRAS, sem o uso de luvas coloridas e/ou luvas de dados e sensores ou a exigência de gravações de alta qualidade em laboratórios com ambientes controlados, focando em sinais que utilizam apenas as mãos. Dada a grande dificuldade de criação de um sistema com este propósito, foi utilizada uma abordagem para o seu desenvolvimento por meio da divisão em etapas. Considera-se que todas as etapas do sistema proposto são contribuições para trabalhos futuros da área de reconhecimento de sinais, além de poderem contribuir para outros tipos de trabalhos que envolvam processamento de imagens, segmentação de pele humana, rastreamento de objetos, entre outros. Para atingir o objetivo proposto foram desenvolvidas uma ferramenta para segmentar sequências de imagens relacionadas à LIBRAS e uma ferramenta para identificar sinais dinâmicos nas sequências de imagens relacionadas à LIBRAS e traduzi-los para o português. Além disso, também foi construído um banco de imagens de 30 palavras básicas escolhidas por uma especialista em LIBRAS, sem a utilização de luvas coloridas, laboratórios com ambientes controlados e/ou imposição de exigências na vestimenta dos indivíduos que executaram os sinais. O segmentador implementado e utilizado neste trabalho atingiu uma taxa média de acurácia de 99,02% e um índice overlap de 0,61, a partir de um conjunto de 180 frames pré-processados extraídos de 18 vídeos gravados para a construção do banco de imagens. O algoritmo foi capaz de segmentar pouco mais de 70% das amostras. Quanto à acurácia para o reconhecimento das palavras, o sistema proposto atingiu 100% de acerto para reconhecer as 422 amostras de palavras do banco de imagens construído, as quais foram segmentadas a partir da combinação da técnica de distância de edição e um esquema de votação com um classificador binário para realizar o reconhecimento, atingindo assim, o objetivo proposto neste trabalho com êxito. / The recognition of sign language is an important research area that aims to mitigate the obstacles in the daily lives of people who are deaf and/or hard of hearing and increase their integration in the majority hearing society in which we live. Based on this, this dissertation proposes the development of an information system for automatic recognition of Brazilian Sign Language (BSL), which aims to simplify the communication between deaf talking in BSL and listeners who do not know this sign language. The recognition is accomplished through the processing of digital image sequences (videos) of people communicating in BSL without the use of colored gloves and/or data gloves and sensors or the requirement of high quality recordings in laboratories with controlled environments focusing on signals using only the hands. Given the great difficulty of setting up a system for this purpose, an approach divided in several stages was used. It considers that all stages of the proposed system are contributions for future works of sign recognition area, and can contribute to other types of works involving image processing, human skin segmentation, object tracking, among others. To achieve this purpose we developed a tool to segment sequences of images related to BSL and a tool for identifying dynamic signals in the sequences of images related to the BSL and translate them into portuguese. Moreover, it was also built an image bank of 30 basic words chosen by a BSL expert without the use of colored gloves, laboratory-controlled environments and/or making of the dress of individuals who performed the signs. The segmentation algorithm implemented and used in this study had a average accuracy rate of 99.02% and an overlap of 0.61, from a set of 180 preprocessed frames extracted from 18 videos recorded for the construction of database. The segmentation algorithm was able to target more than 70% of the samples. Regarding the accuracy for recognizing words, the proposed system reached 100% accuracy to recognize the 422 samples from the database constructed (the ones that were segmented), using a combination of the edit distance technique and a voting scheme with a binary classifier to carry out the recognition, thus reaching the purpose proposed in this work successfully.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-04-12T19:29:28Z No. of bitstreams: 1 flaviosouzarodrigues.pdf: 1707181 bytes, checksum: 731154a321c494d35da614e5bf732452 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-04-18T13:16:49Z (GMT) No. of bitstreams: 1 flaviosouzarodrigues.pdf: 1707181 bytes, checksum: 731154a321c494d35da614e5bf732452 (MD5) / Made available in DSpace on 2017-04-18T13:16:49Z (GMT). No. of bitstreams: 1 flaviosouzarodrigues.pdf: 1707181 bytes, checksum: 731154a321c494d35da614e5bf732452 (MD5) Previous issue date: 2016-10-21 / Esta dissertação apresenta, como objeto de estudo, a aquisição da Língua Brasileira de Sinais como primeira língua de crianças e jovens surdos, filhos de pais ouvintes, e discute a importância da aquisição espontânea dessa língua em idade semelhante à que crianças ouvintes adquirem a língua oral. Em consonância com a abordagem bilíngue, assume-se que o acesso à língua de sinais permite o desenvolvimento linguístico do surdo de forma natural e espontânea (QUADROS, 2005; MAHER; 2007; QUADROS & SCHMIEDT, 2006; QUADROS & CRUZ, 2011). Seguindo essa abordagem, considera-se, neste trabalho, a Libras como primeira língua (L1) e o Português Brasileiro como segunda língua (L2). O objetivo do estudo em questão é o de caracterizar, por meio de uma metodologia de base experimental, as consequências decorrentes da aquisição da Libras por essas crianças e jovens, iniciada em diferentes contextos e, em muitos casos, tardiamente, ou seja, após os 4 anos. O atraso de linguagem (compreensiva e expressiva), em nível cognitivo, implica dificuldades de percepção, atenção, memória, afetando a capacidade de generalização, formação de conceitos, dentre outras. A hipótese que norteia esta pesquisa é a de que a língua de sinais (neste caso, a Libras) permite resolver dificuldades concernentes ao desenvolvimento das funções mentais superiores, que necessitam da língua como mediadora nesse processo. Assume-se uma concepção de aquisição da linguagem inatista, segundo a qual, independentemente da qualidade do input a que a criança está exposta, por ser algo ativado a partir de poucos elementos disponíveis, efetiva-se a aquisição da língua (CHOMSKY, 1965, 1981, 1995). Considera-se, ainda, uma perspectiva psicolinguística de aquisição da linguagem – Bootstrapping Sintático (GLEITMAN, 1990) e Semântico (PINKER, 1987; 1989). Os resultados deste estudo sugerem que quanto mais tardia a aquisição da Libras como primeira língua, mais significativo o impacto na dificuldade de julgamento de estados mentais por crianças surdas, cujo acesso ao input convencional não ocorreu na fase inicial de aqusição da linguagem. / This dissertation has as its study object the acquisition of Brazilian sign language as the first language of deaf children and young individuals, who have hearing parents, and debates over the importance of a spontaneous acquisition of such language at a similar age hearing children acquire oral language. In accordance with a bilingual approach, we assume that the access to the sign language allows the linguistic development of deaf people in a natural and spontaneous way (QUADROS, 2005; MAHER; 2007; QUADROS & SCHMIEDT, 2006; QUADROS & CRUZ, 2011). According to such approach, it takes into account in the present work Libras as a first language (L1) and the Brazilian Portuguese as a second one (L2). This study aims at characterizing, by means of an experimental basis methodology, the consequences arising from Libras acquisition by those children and young individuals, initiated in different contexts and, in most cases, later, that is, after the age of four. Language delay (receptive and expressive), in a cognitive level, implies perception, attention and memory difficulties, affecting the ability of generalization, concept formation, among others. The hypothesis that guides this study is that the sign language (in this case, Libras) allows to solve problems concerning the development of higher mental functions, which require the language as a mediator in this process. We assume an inate conception of language acquisition, acordding to which, independently from the quality of input the child is exposed to, for being triggered from few availabe elements, the language is acquired (CHOMSKY, 1965, 1981, 1995). We also assume a psycholinguistic perspective of language acquisition– Syntactic Bootstrapping (GLEITMAN, 1990) and Semantic Boostrapping (PINKER, 1987; 1989). The results suggest the later the aquisition of Libras as a first language the more significative will be the impact on the difficulty of judging mental states by deaf children whose access to the conventional input did not occur in the initial stage of language acquisition.