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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

Bacillus cereus: Caracterização genômica na cadeia produtiva de leite e influência da pasteurização na expressão de genes relacionados a toxinas diarreicas / Bacillus cereus: Genomical characterization on dairy production chain and influence of pasteurization on expression of genes related to diarrheic toxins

Rossi, Gabriel Augusto Marques 06 December 2017 (has links)
Submitted by Gabriel Augusto Marques Rossi null (gabrielrossiveterinario@hotmail.com) on 2018-01-10T19:18:16Z No. of bitstreams: 1 Tese_Gabriel_Augusto_Marques_Rossi.pdf: 3246904 bytes, checksum: 2ed62292bd3bfa8f9ec88fe41c5bbaa2 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-01-11T10:23:42Z (GMT) No. of bitstreams: 1 rossi_gam_dr_jabo.pdf: 3246904 bytes, checksum: 2ed62292bd3bfa8f9ec88fe41c5bbaa2 (MD5) / Made available in DSpace on 2018-01-11T10:23:42Z (GMT). No. of bitstreams: 1 rossi_gam_dr_jabo.pdf: 3246904 bytes, checksum: 2ed62292bd3bfa8f9ec88fe41c5bbaa2 (MD5) Previous issue date: 2017-12-06 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As bactérias pertencentes ao grupo do Bacillus cereus são importantes para indústrias processadoras de leite e produtos lácteos devido à capacidade de sobrevivência aos tratamentos térmicos utilizados durante os processamentos, e consequente deterioração dos produtos e risco à saúde pública. Assim, inicialmente, objetivou-se compreender a estrutura populacional de isolados pertencentes ao grupo do B. cereus na cadeia produtiva do leite e produtos lácteos. Por meio da utilização de amostragem estruturada e técnicas genômicas comparativas, investigou-se quais linhagens específicas e genes estão significativamente associados a estágios de produção específicos e produtos. Os genomas de 69 isolados obtidos de equipamentos, leite cru e produtos lácteos foram comparados com outros 193 disponíveis de diversas origens. A estrutura populacional incluiu os conhecidos grupos filogenéticos II, III, IV, V e VI, e quase todos os isolados dos produtos lácteos pertenceram ao grupo III. A investigação de genes específicos revelou um grande número de isolados carreando aqueles relacionados à produção de toxinas, como o cytK (53,62%), hblA (59,42%), hblC (44,93%), hblD (53,62%), nheA (84,06%), nheB (89,86%), nheC (84,06%), cesA (2,90%) e cesB (2,90%). Os isolados pertencentes aos grupos IV e V possuíram uma prevalência significativamente maior dos genes hblACD e o grupo IV do gene cytK. Os isolados obtidos de produtos lácteos tiveram uma prevalência significativamente menor dos genes cytK e hblACD comparados aos de equipamentos e leite cru/tanques de refrigeração. A análise genômica populacional demonstrou a diversidade dos isolados e a variedade de funções dentro do grupo do B. cereus da cadeia produtiva leiteira, com grande número de isolados potencialmente capazes de causar doenças alimentares. Posteriormente, objetivou-se avaliar a viabilidade do processo de tindalização de leite cru refrigerado e determinar se o processo de pasteurização do leite influencia na expressão dos genes relacionados à produção das toxinas diarreicas pelo B. cereus s.s. em leite experimentalmente contaminado. Para isso, realizou-se um processo de tindalização de leite cru refrigerado e então foi realizada a contaminação com um isolado potencialmente toxigênico, e, posteriormente, o mesmo foi pasteurizado, envasado e mantido em refrigeração durante 10 dias. Em momentos determinados, foram coletadas amostras do produto afim de avaliar a expressão de genes codificadores de toxinas (hblACD, nheABC e cytK). O protocolo de tindalização utilizado permitiu redução logarítmica da população de bactérias do grupo do B. cereus e foi possível detectar a expressão do gene hblA em amostras de leite 5 e 10 dias após a pasteurização. Conclui-se que o modelo proposto foi adequado e que a expressão do gene hblA não foi inibida após a realização da pasteurização do leite, demonstrando o potencial risco aos consumidores decorrentes do consumo de leite pasteurizado contaminado. / The bacteria belonging to Bacillus cereus group are important to dairy industries due their ability to survive to thermal treatments used during processing, and consequently cause food spoilage and risk to public health. Thus, firstly, this study aimed to better understand the population structure of B. cereus group isolates in dairy production chain. Using structured sampling of B. cereus in dairy production chain and comparative genomics techniques, we investigated if specific lineages and genes are significantly overrepresented in particular production stages. The genomes of 69 isolates obtained from equipments, raw milk and dairy products were compared with others 193 avaiable from several origins. The populational structure included the known phylogenetic groups II, III, IV, V and V, and almost all isolates from dairy products belonged to group III. The genes investigation showed a high number of isolates carrying genes related to toxins production, such as cytK (53.62%), hblA (59.42%), hblC (44.93%), hblD (53.62%), nheA (84.06%), nheB (89.86%), nheC (84.06%), cesA (2.90%) and cesB (2.90%). The isolates belonging to groups IV and V had a significant higher prevalence of genes hblACD an group VI of cytK. The isolates obtained from dairy products had a significant lower prevalence of genes cytK and hblACD compared to those from equipments and raw milk/bulk tanks. The populational genomic analyses showed the diversity of isolates and variability of functions in B. cereus group in dairy production chain, with a high number of isolates potentially able to cause foodborne disease. Posteriorly, this study aimed to evaluate the viability of tyndallizating raw milk and to establish if milk’s pasteurization influences on the expression of genes related to the production of diarrheal toxins by B. cereus s.s. using a milk contamined experimentally. For this purpose, the tyndallization of raw milk was performed and later it was contaminated with a potentially toxigenic isolate, and, posteriorly, it was pasteurized, packaged and kept under refrigeration during 10 days. In established periods, samples of this product were collected in order to evaluate the expression of genes related to toxins production (hblACD, nheABC and cytK). The protocol used for tyndallization allowed a logarithmic reduction of population of B. cereus group and the expression of hblA gene was detected in samples from milk after 5 and 10 days after pasteurization. It was concluded that the proposed model was appropriate and the expression of hblA gene was not inihibited after milk pasteurization, highlighting the potential risk for consumers through consumption of contamined pasteurized milk. / 2016/19214-9 / 2014/13104-1
452

Filogenia de Seirinae (Collembola, Entomobryoidea, Entomobryidae) na regi?o Neotropical baseada em genomas mitocondriais completos

Godeiro, Neriv?nia Nunes 27 September 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-12-12T19:48:28Z No. of bitstreams: 1 NerivaniaNunesGodeiro_TESE.pdf: 42759157 bytes, checksum: 096a840516dd298c1623004a0fa0476d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-12-14T20:25:43Z (GMT) No. of bitstreams: 1 NerivaniaNunesGodeiro_TESE.pdf: 42759157 bytes, checksum: 096a840516dd298c1623004a0fa0476d (MD5) / Made available in DSpace on 2017-12-14T20:25:43Z (GMT). No. of bitstreams: 1 NerivaniaNunesGodeiro_TESE.pdf: 42759157 bytes, checksum: 096a840516dd298c1623004a0fa0476d (MD5) Previous issue date: 2017-09-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Seirinae ? uma das mais diversas subfam?lias de Collembola, e grande parte dessa diversidade ? devida a Seira Lubbock que possui, aproximadamente, 220 esp?cies reconhecidas. At? o momento, nenhuma filogenia interna foi proposta para o t?xon, o que dificulta a organiza??o do conhecimento para compara??o, descri??o de novas esp?cies e g?neros, al?m da pr?pria compreens?o dos seus padr?es evolutivos. A quetotaxia dorsal ? o principal componente morfol?gico utilizado para distinguir esp?cies, e embora comprovadamente diagn?stico, pode ser vari?vel intraespecificamente. O principal objetivo deste trabalho ? esclarecer as rela??es filogen?ticas entre os Seirinae neotropicais, do ponto de vista molecular e morfol?gico, o que poder? resultar numa melhor organiza??o interna da subfam?lia. Para tanto, foram sequenciadas 27 amostras de diferentes esp?cies de Entomobryidae e uma de Paronellidae. Para as an?lises moleculares, foi extra?do e quantificado o DNA total de um indiv?duo/amostra e bibliotecas foram constru?das e sequenciadas por Next Generation Sequencing utilizando o HiSeq 2000. O genoma mitocondrial (DNAmt) completo das esp?cies foi reconstru?do atrav?s de an?lises de bioinform?tica utilizando duas metodologias: SOAPdenovo_Trans e MIRA/MITOBim. Duas filogenias foram propostas: uma contendo somente os genomas reconstru?dos neste trabalho e outra complementar, onde foram inclu?dos 11 DNAmt de Collembola disponibilizados em bancos de dados online. As filogenias foram feitas por an?lises Bayesianas utilizando os treze genes codificantes proteicos que correspondem a quase totalidade do DNAmt. Os resultados corroboram com a proposta atual que a ordem Poduromorpha ? a mais basal de Collembola; a ordem Symphypleona aparece como grupo-irm?o de Entomobryomorpha, que apresenta clara divis?o em duas superfam?lias, Isotomoidea e Entomobryoidea; o posicionamento dos g?neros Lepidocyrtoides Sch?tt e Lepidosira Sch?tt dentro de Entomobryinae corroboram com a mais recente filogenia publicada; a monofilia de Seirinae e seus grandes grupos internos foi comprovada pela primeira vez por dados moleculares com alto apoio nodal; o g?nero Tyrannoseira Bellini & Zeppelini, recentemente descrito, foi validado filogeneticamente; Lepidocyrtinus B?rner foi al?ado a status de g?nero; e tr?s sinon?mias de esp?cies foram propostas; por fim, algumas caracter?sticas morfol?gicas de Seirinae foram identificadas como diagn?sticas e com sinal filogen?tico, como por exemplo, a quantidade de macroquetas no primeiro segmento abdominal. / Seirinae is one of the most diverse subfamilies of Collembola, and a considerable part of this diversity is comprised by Seira Lubbock, which currently gathers approximately 220 species. So far no internal phylogeny Seirinae was proposed, what leads to difficulties in the establishment of comparative knowledge, description of new taxa, and also the understanding of the evolutionary patterns within this taxon. The dorsal chaetotaxy is the main morphological component utilised to distinguish species, and although undoubtedly diagnostic, it can be variable interspecifically. The main aim of this work is to clarify the phylogenetic relations within the Neotropical Seirinae based on both molecular and morphological data, which might result in a better internal organization of the subfamily. For this aim, 27 samples of different species belonging to Entomobryidae and one of Paronellidae were sequenced. As for molecular analyses genomic DNA of one individual/sample was extracted and quantified and sequencing libraries were built and sequenced using Next-Generation Sequencing on HiSeq 2000. The whole mitochondrial genome (DNAmt) of the species was reconstructed by two methods: SOAPdenovo_Trans and MIRA/MITOBim. Two phylogenies were then proposed: one containing only genomes reconstructed in this study as well as a complementary one, where 11 Collembola DNAmt available in a public database were also included. The phylogenies were generated through Bayesian analyses using the thirteen protein coding genes that almost correspond to the entire DNAmt. The results corroborate the current proposal which claims the order Poduromorpha as the most basal order of Collembola; the order Symphypleona as the sister-group of Entomobryomorpha, which shows clear division into two superfamilies, Isotomoidea and Entomobryoidea; the placement of Lepidocyrtoides Sch?tt and Lepidosira Sch?tt genera inside Entomobryinae corroborates the most recently published phylogeny; the monophyly of the internal groups of Seirinae based on molecular evidence was confirmed for the first time showing high nodal support; Tyrannoseira Bellini & Zeppelini, recently described, was validated phylogenetically; Lepidocyrtinus B?rner was elevated to genus status; and three species synonyms were proposed; finally some morphological characteristics of Seirinae were identified as diagnostic and having phylogenetic signal, for instance, the quantity of macrochaetae on the first abdominal segment.
453

Understanding early transcriptional events in Staphylococcus aureus infection

Lindemann, Claudia January 2017 (has links)
Staphylococcus aureus remains an important pathogen, which, due to its capability to develop antimicrobial resistance, imposes an increasing threat to human health. Developing preventive means to decrease disease burden is a major aim. However, the development of an S. aureus vaccine, which would be one strategy to achieve such goals, has been complicated through limited understanding of the bacterium's pathogenic mechanisms. This work uses four approaches to address these limitations: Firstly, a reproducible RNA sequencing based method for the determination of gene transcription by S. aureus in vivo during mammalian infection. Secondly, examination of the impact of the bacterial transcription regulator 'Rsp' on the bacterium, which shows that mutations in this gene have profound functional and transcriptional impacts. Thirdly, by examining the in vivo transcription of multiple S. aureus strains during infection, proposing a 'core in vivo transcriptome' of induced genes under the conditions tested. Some of these genes are known to be involved in pathogenesis, others are not completely characterised and may represent suitable vaccine antigens. Finally, this work addresses limited understanding of S. aureus pathogenesis through defining transcriptional changes in vivo, which are induced by an altered immune response in immunised hosts. Together, this body of work contributes to the understanding of S. aureus pathogenesis and provides candidate antigens for future vaccine development.
454

The oocyte-activation factor, phospholipase C zeta (PLCζ) : clinical prognosis, diagnosis, and treatment of oocyte activation deficiency

Amdani, Siti Nornadhirah January 2018 (has links)
Oocyte activation deficiency (OAD) is an infertile condition observed in patients who have experienced recurrent total fertilisation failure (TFF) following intracytoplasmic sperm injection treatment. This condition was considered to be an idiopathic factor for a long time but strong clinical evidence now suggests that dysfunctional forms of phospholipase C zeta (PLCζ) may be predominant causative factors for OAD. Genetic contribution has played a role in patients suspected of having OAD, as four PLCζ exonic mutations have been discovered and characterised as being the cause of infertility. In this study, a novel nonsense mutation, PLCζK322Stop, was identified in the PLCζ XY-linker region of Patient LR. This variant results in the truncation of approximately half of PLCζ, therefore was non-functional when activity was tested. Patient LR, which also exhibited a previously reported mutation, PLCζH233L, may suggest that the patient is sub-fertile, as opposed to being infertile, as initially expected. Although research has purely focused upon the coding regions of PLCζ, it was obvious that our knowledge of PLCζ regulatory elements remain very limited. Next generation sequencing (NGS) was therefore employed to detect variants in the non-coding regions of PLCζ, promoter and introns, which may have resulted in the observed phenotypic diversity of PLCζ expression in fertile and infertile patients. As a result of mapping failure, an alternative approach was considered to identify variants within human PLCζ, and this involved using the single nucleotide polymorphism (SNP) database. Over 2500 SNPs were localised in the intronic regions of PLCζ and thus, it could be speculated that these variants may help elucidate the wide variation of PLCζ expression reported. Additionally, two particular patients with TFF (79 and 107) were investigated in this study to identify an association with PLCζ and their infertile state. For Patient 79, multiple PLCζ immunofluorescence analysis was performed and a significant improvement in PLCζ expression was observed one year after his first investigation. This may have been the result of an external factor, which influenced protein expression. As for Patient 107, a novel substitution mutation, PLCζV193E, was identified and was predicted to affect PLCζ stability and folding. There is global interest to create a safer and alternative OAD therapy, namely a human recombinant PLCζ protein (hrPLCζ). The first method, using a bacterial cell line resulted in successful purification and identification but the product proved to be inactive following mouse oocyte microinjection. The second method involved production of a mammalian-expressed hrPLCζ, which was successfully purified and identified but due to time restrictions, could not be tested for functionality. Concurrently, the findings in this thesis have reinforced the association between PLCζ and OAD, and provided improved options for the diagnosis and treatment of OAD.
455

Future developments and trends in use of picture archiving and communication systems

Alhajeri, Mona January 2016 (has links)
Objectives: This study identifies modern information technologies that can improve the clinical practice of Picture Archiving and Communication Systems (PACS) and determines the approaches that are needed to improve the functionality of current PACS to provide better next generation PACS and to improve the future of radiology practices and workflow with future PACS generations. Method: A parallel mixed method approach was adopted including qualitative method (semi-structured interviews), quantitative method (questionnaire survey) and observation of online discussion groups on PACS. Five databases were searched to find salient literature, including Science Direct, Springer Link, Scopus, CINAHL Plus and Google Scholar. Six radiologists were interviewed and questionnaires were collected from 120 radiologists. Four online discussion groups related to PACS were monitored via LinkedIn. The data were analysed thematically using the thematic analysis method. Finally, a focus group was held with a separate group of radiologists to validate the findings. Results: Eight themes emerged from the thematic analysis of the data: (1) limitations of traditional PACS; (2) user needs and requirements that can increase PACS functionality; (3) Web based solutions of PACS; (4) PACS on mobile phones; (5) Vendor Neutral Archive (VNA); (6) full integration of voice recognition in PACS; (7) backup solutions for the system and (8) continuous training for PACS users. Discussion: With the development of healthcare information and communication technology (ICT) and with the increased demands of the radiologists to expand PACS usability, traditional PACS must be updated to follow the changes. Modern technologies can provide better solutions to enhance the functionality of current PACS. The next generation of PACS can fulfil the future requirements of users. This study considers the issues between the needs and requirements of the users of a PACS system in the future and the developing solutions in ICT and the PACS industry. Moreover, highly developed PACS systems with advanced features will have a direct impact in changing and improving radiology workflow. Accordingly, a model has been developed that proposes new features for the next generation PACS system, which may be applied to the next generation radiology practice. The model was validated with the focus group and, by using a separate group of radiologists in another country, was determined to be generalisable. Conclusion: It is widely recognised that traditional PACS must be updated to adopt recent advances in ICT. This research has identified themes that, when incorporated, will enhance the functionality of PACS and radiology workflow and provide better quality clinical practice. The findings from this empirical research can be used: as recommendations to vendors; for technology development; and by medical institutes to consider aspects when undertaking implementation of PACS and training future radiologists. Keywords: 'Picture archiving and communication system’, PACS, Future trends, next generation, Organisational efficiency, Productivity, Clinical practice, Ubiquitous.
456

MAC AND APPLICATION LAYER PROTOCOLS FOR HIGH PERFORMANCE NETWORKING

Mehta, Anil 01 August 2011 (has links)
High-performance networking (HPN) is of significance today in order to enable next-generation applications using wired and wireless networks. Some of the examples of HPN include low-latency industrial sensing, monitoring and automation using Wireless Sensor Networks (WSNs). HPN however requires protocol optimization at many layers of the open system interface (OSI) network model in order to meet the stringent performance constraints of the given applications. Furthermore, these protocols need to be impervious to denial of service (DoS) and distributed DoS (DDoS) attacks. Some of the key performance aspects of HPN are low point-to-point and end-to-end latency, high reliability of transmitted frames and performance predictability under various network load situations. This work focuses on two discrete issues in designing protocols for HPN applications. The first research issue looks at the Medium Access Control (MAC) layer of the OSI network model for designing of MAC protocols that provide low-latency and high reliability for point-to-point communication under a WSN. Existing standards in this area are governed by IEEE 802.15.4 specification which defines protocols for MAC and PHY layers for short-range, low bit-rate, and low-cost wireless networks. However, the IEEE 802.15.4 specification is inefficient in terms of latency and reliability performance and, as a result, is unable to meet the stringent operational requirements as defined by counterpart wired sensor networks. Work presented under current research issue describes new MAC protocols that are able to show low-latency transmission performance under strict timing constants for power limited WSNs. This enhancement of the MAC protocols is named extended GTS (XGTS) contained under extended CFP (ECFP) and is published under the IEEE's 802.15.4e standard. The second research issue focuses on the application layer of the OSI network model to design protocols that enhance the robustness of the text based protocols to various traffic inputs. The purpose of this is to increase the reliability of the given text based application layer protocol under a varied load. Session Initiation Protocol (SIP) is used as a case study and the work aims to build algorithms that ensure that SIP can continue to function under specific traffic conditions, which would otherwise deem the protocol useless due to DoS and DDoS attacks. Proposed algorithms investigate techniques that enhance the robustness of the SIP against parsing attacks without performing a deep parse of the protocol data unit (PDU). The desired effect of this is to reduce the time spent in parsing the SIP messages at a SIP router and as a result increase the number of SIP messages processed per unit time at a SIP router.
457

Next generation sequencing-based genotyping of human blood groups : FY, JK and ABO genes

Altayar, Malik Abdullah January 2017 (has links)
Serological discrepancies in matching blood group antigens between donors and patients for blood transfusion may lead to alloimmunisation, especially in multiply transfused patients. Blood group genotyping (BGG) has contributed in reducing this issue. ABO, Fy and Jk antigens are among those to be causative for alloimmunisation through transfusion or pregnancy. The number of alleles of these clinically significant blood groups is ever increasing. Currently, all commercially available high-throughput BGG platforms are only based on pre-defined polymorphisms. Consequently, novel or rare alleles that might have clinical significance are not identified. Next generation sequencing (NGS) circumvents this issue by providing high-throughput comprehensive genotyping of blood group genes in discovery mode to find all existing and novel mutations. Accordingly, a large number of individuals can be genotyped in a single run. Here, we describe an NGS-based method coupled with long-range polymerase chain reaction (LR-PCR) for high-throughput, rapid and extensive genotyping of FY, JK and ABO blood group genes. The Ion Torrent Personal Genome Machine (PGMTM) was used for sequencing the entire FY, JK and ABO blood group genes including flanking regions. Accordingly, high resolution genotyping was obtained. 53 genomic DNA samples were sequenced and genotyped for FY, 67 for JK and 47 for ABO. Sequencing data were aligned to the gene reference sequence derived from the human genome (hg19) to analyse variants. Analysis was accomplished by software packages, such as Ion Torrent SuiteTM plugins. Sanger sequencing of cDNA and cDNA clones was used to confirm findings in the JK gene. The sequencing data had a coverage depth of more than 5000x for FY, 700x for JK and 600x for ABO. NGS data matched with the serological phenotypes of FY alleles FY*A, FY*B and FY*02 Null main polymorphisms, such as FY*A/FY*B (125G > A) in exon 2 and (-67 T > C) in the promotor region. JK variant analysis revealed that the JK*01W.01 allele (130G > A) is common (10/67 samples) with normal antigenicity. The previously described silencing polymorphism (810G > A), leading to a purported JK*B null allele, restores a splice site and does not correlate with loss of Jkb antigenicity (10/67 samples). JK intron analysis revealed several new JK alleles described in this thesis. All 7 exons, introns and the flanking regions of the ABO gene were covered by only four amplicons. Several rare O alleles were found, such as O73 and O75, while one suggested novel O allele was characterised by a missense SNP 482G > A (Arg161His) in exon 7. The ABO reference sequence from hg19 appeared to resemble (O01 and O02) alleles. The intronic SNPs might be used to distinguish between alleles more accurately as a correlation of the intronic SNPs with the alleles was noted for the homozygous O alleles. It is predicted that NGS-based genotyping will replace not only microarray-based genotyping but also serology in the blood group typing of individuals, with great advancements in technology and molecular knowledge being expected in the near future.
458

Sex determination and genetic management in Nile tilapia using genomic techniques

Khanam, Taslima January 2017 (has links)
The PhD research studied two aspects in tilapia, firstly the analysis of sex determination in Nile tilapia (evidence of complex sex-determining systems) and secondly the genetic management of the tilapia species, using different genomic analysis approaches. This research started with the development of two techniques: minimally invasive DNA sampling from fish mucus, which was found to be suitable for standard genotyping and double-digest restriction-site associated DNA sequencing – ddRADseq; and pre-extraction pooling of tissue samples for ddRADseq (BSA-ddRADseq), which was found to be suitable for identifying a locus linked to a trait of interest (sex in this case). The first molecular evidence concerning the sex determination in genetically improved farmed tilapia (GIFT) was described using BSA-ddRADseq. Given the multiple stock origin of GIFT, surprisingly only a single locus (in linkage group 23) was found to be associated with the phenotypic sex across the population. The first evidence of LG23 influence on phenotypic sex in the Stirling population of Nile tilapia was also found. Different combinations of estrogen hormones and high temperature were tested for feminising Nile tilapia: a combined treatment of estrogen hormone and high temperature was found to be more efficient in feminising Nile tilapia than the estrogen alone. A set of species-diagnostic SNP markers were tested which were found to be suitable to distinguish pure species (O. niloticus, O. mossambicus and O. aureus), and these were used to analyse species contribution to GIFT and a selected tilapia hybrid strain. The results of the current research added novel information to our understanding of sex determination in Nile tilapia, which will be helpful in the development of marker-assisted selection in GIFT and other Nile tilapia strains towards the production of all male offspring. The methods developed also have broader applicability in genetic and genomics research.
459

Uma proposta de integração das redes UMTS e IEEE 802.11 com suporte a mobilidade / A proposal of integration of the nets UMTS and IEEE 802,11 with support mobility

Nogueira, Antonia Diana Braga January 2007 (has links)
NOGUEIRA, Antonia Diana Braga. Uma proposta de integração das redes UMTS e IEEE 802.11 com suporte a mobilidade. 2007. 112 f. Dissertação (Mestrado em ciência da computação)- Universidade Federal do Ceará, Fortaleza-CE, 2007. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-08T18:49:42Z No. of bitstreams: 1 2007_dis_adbnogueira.pdf: 13756193 bytes, checksum: bb4a338bd2622ad6f90479ce37824ccd (MD5) / Approved for entry into archive by Rocilda Sales (rocilda@ufc.br) on 2016-07-18T13:41:19Z (GMT) No. of bitstreams: 1 2007_dis_adbnogueira.pdf: 13756193 bytes, checksum: bb4a338bd2622ad6f90479ce37824ccd (MD5) / Made available in DSpace on 2016-07-18T13:41:19Z (GMT). No. of bitstreams: 1 2007_dis_adbnogueira.pdf: 13756193 bytes, checksum: bb4a338bd2622ad6f90479ce37824ccd (MD5) Previous issue date: 2007 / Wireless Local Area Networks (WLANs) IEEE 802.11 reach relatively high data transmission rates when compared to other wireless networks, such as Bluetooth. These high data transmission rates have gained attention from the cellular networks operators, which have been considering IEEE 802.11 networks as a complement to their access networks. This interoperability between cellular systems and WLANs has been frequently discussed in the literature. For example, 3GPP (Third Generation Partnership Project) has defined six levels for the complete integration of the third generation cellular networks and WLANs. However, the mobility support has not been specified yet, which is necessary to make feasible voice and data transmission transparence for the final users. Thus, this work presents two approaches for the mobility management of the integration between UMTS and IEEE 802.11 networks: the first one is based on SIP (Session Initiation Protocol), and the other one is based on MIPv6 (Mobile IP version 6). This proposal extends the Loose Interworking architecture and uses the fourth level of the 3GPP specification. First, these approaches are modeled using sequence diagrams and, then, they are mapped to the SDL (Specification and Description Language) formal description technique. SDL, which is largely used to formally specify telecommunications systems, presents simulation and validation procedures that are applied to evaluate the specification and, consequently, the proposed approaches. / As redes locais sem fio (Wireless Local Area Networks - WLANs) IEEE 802.11 atingem taxas de transmissão de dados relativamente altas quando comparadas `a outras redes sem fio, por exemplo, Bluetooth. Essas altas taxas de transmissãao têm interessado as operadoras de redes celulares, as quais começam a ver as redes IEEE 802.11 como um complemento as suas redes de acesso. Esta interoperabilidade entre sistemas celulares e WLANs tem sido um tema bastante discutido na literatura. Por exemplo, o 3GPP (Third Generation Partnership Project) define seis n´ıveis para a total integração das redes celulares de terceira geração com as redes locais sem fio. No entanto, a integração com suporte a mobilidade ainda não foi especificada, o que é necessário para viabilizar a transparência de transmissão de voz e dados para os usuários finais. Esta dissertação apresenta então duas abordagens para o gerenciamento de mobilidade na integração do sistema 3G UMTS com as redes IEEE 802.11: uma baseada no SIP (Session Initiation Protocol ) e a outra no MIP versão 6 (Mobile IP version 6 - MIPv6). A proposta estende a arquitetura Loose Interworking e utiliza os requisitos do nível 4 do 3GPP. Para especificar a proposta, as abordagens de integração das redes UMTS e IEEE 802.11 foram modeladas em diagramas de seqüência e, em seguida, mapeadas para a técnica de descrição formal SDL (Specification and Description Language). SDL, que é bastante utilizada para especificar formalmente sistemas de telecomunicações, apresenta procedimentos de simulação e validação que são aplicados para avaliar a especificação e, em conseqüência, as abordagens propostas.
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Uma proposta de integração das redes UMTS e IEEE 802.11 com suporte a mobilidade / A proposal of integration of the nets UMTS and IEEE 802,11 with support mobility

Nogueira, Antonia Diana Braga January 2007 (has links)
NOGUEIRA, Antonia Diana Braga. Uma proposta de integração das redes UMTS e IEEE 802.11 com suporte a mobilidade. 2007. 91 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências, Departamento de Computação, Fortaleza-CE, 2007. / Submitted by guaracy araujo (guaraa3355@gmail.com) on 2016-05-30T19:51:57Z No. of bitstreams: 1 2007_dis_adbnogueira.pdf: 13756193 bytes, checksum: bb4a338bd2622ad6f90479ce37824ccd (MD5) / Approved for entry into archive by guaracy araujo (guaraa3355@gmail.com) on 2016-05-30T19:52:27Z (GMT) No. of bitstreams: 1 2007_dis_adbnogueira.pdf: 13756193 bytes, checksum: bb4a338bd2622ad6f90479ce37824ccd (MD5) / Made available in DSpace on 2016-05-30T19:52:27Z (GMT). No. of bitstreams: 1 2007_dis_adbnogueira.pdf: 13756193 bytes, checksum: bb4a338bd2622ad6f90479ce37824ccd (MD5) Previous issue date: 2007 / Wireless Local Area Networks (WLANs) IEEE 802.11 reach relatively high data transmission rates when compared to other wireless networks, such as Bluetooth. These high data transmission rates have gained attention from the cellular networks operators, which have been considering IEEE 802.11 networks as a complement to their access networks. This interoperability between cellular systems and WLANs has been frequently discussed in the literature. For example, 3GPP (Third Generation Partnership Project) has defined six levels for the complete integration of the third generation cellular networks and WLANs. However, the mobility support has not been specified yet, which is necessary to make feasible voice and data transmission transparence for the final users. Thus, this work presents two approaches for the mobility management of the integration between UMTS and IEEE 802.11 networks: the first one is based on SIP (Session Initiation Protocol), and the other one is based on MIPv6 (Mobile IP version 6). This proposal extends the Loose Interworking architecture and uses the fourth level of the 3GPP specification. First, these approaches are modeled using sequence diagrams and, then, they are mapped to the SDL (Specification and Description Language) formal description technique. SDL, which is largely used to formally specify telecommunications systems, presents simulation and validation procedures that are applied to evaluate the specification and, consequently, the proposed approaches. / As redes locais sem fio (Wireless Local Area Networks - WLANs) IEEE 802.11 atingem taxas de transmissão de dados relativamente altas quando comparadas `a outras redes sem fio, por exemplo, Bluetooth. Essas altas taxas de transmissãao têm interessado as operadoras de redes celulares, as quais começam a ver as redes IEEE 802.11 como um complemento as suas redes de acesso. Esta interoperabilidade entre sistemas celulares e WLANs tem sido um tema bastante discutido na literatura. Por exemplo, o 3GPP (Third Generation Partnership Project) define seis n´ıveis para a total integração das redes celulares de terceira geração com as redes locais sem fio. No entanto, a integração com suporte a mobilidade ainda não foi especificada, o que é necessário para viabilizar a transparência de transmissão de voz e dados para os usuários finais. Esta dissertação apresenta então duas abordagens para o gerenciamento de mobilidade na integração do sistema 3G UMTS com as redes IEEE 802.11: uma baseada no SIP (Session Initiation Protocol ) e a outra no MIP versão 6 (Mobile IP version 6 - MIPv6). A proposta estende a arquitetura Loose Interworking e utiliza os requisitos do nível 4 do 3GPP. Para especificar a proposta, as abordagens de integração das redes UMTS e IEEE 802.11 foram modeladas em diagramas de seqüência e, em seguida, mapeadas para a técnica de descrição formal SDL (Specification and Description Language). SDL, que é bastante utilizada para especificar formalmente sistemas de telecomunicações, apresenta procedimentos de simulação e validação que são aplicados para avaliar a especificação e, em conseqüência, as abordagens propostas.

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