The glpX gene of Escherichia coli encodes fructose 1,6-bisphosphatase II (FBPase II), an enzyme that would appear to be redundant with FBPase I, encoded by fbp. However, glpX mutants have no apparent phenotype, while fbp mutants are unable to grow on gluconeogenic substrates as sole carbon sources, suggesting that GlpX function is insufficient for growth of fbp mutants under these conditions. To gain insight into the physiological functions of the FBPases, regulation of glpX expression was investigated. It was found that glpX is transcribed as part of a complex glpFKX operon containing promoters upstream of glpF, glpK and glpX (PglpF, PglpK, PglpX, respectively). Transcription start sites of PglpX were found at -24 and -41 relative to the ATG translation initiation site using primer extension analysis. Unlike PglpF, these newly found promoters were not subject to regulation by GlpR or cAMP-CRP. Cra (Catabolite Repressor/Activator) positively regulated expression from PglpK and PglpX by increasing transcription approximately 2 fold. Western analysis using GlpX polyclonal antibodies revealed that GlpX levels were higher in cultures grown on glycerol compared with levels in maltose- or glucose-grown cultures (glycerol>maltose>glucose). Various strains and growth conditions were used to show that GlpX levels are regulated by GlpR, suggesting that PglpF can give rise to expression of glpX. GlpX protein was present in a strain containing a polar insertion in glpK, indicating that PglpX can also give rise to expression of glpX. Strains deficient in FBPase I or CsrA (carbon starvation regulator) did not reveal any difference in GlpX levels with respect to the wild type. All of these data indicate that glpX expression is achieved by its own promoter as well as the operon promoter, PglpF. Finally, the results show that the delta-fbp phenotype is not due to the absence of GlpX. / Ph. D.

[pt] Os bezerros de Arão e Jeroboão: Uma verificação da relação intertextual entre Ex 32,1-6 e 1 Rs 12,26-33 tem por objetivo tanto verificar a existência das várias relações intertextuais entre as passagens de Ex 32,1-6 e 1 Rs 12,26-33 quanto apresentar e demonstrar como se manifesta essa intertextualidade. Esta tese faz uso do método sincrônico da análise narrativa. A necessidade de trabalhar com o método sincrônico da análise narrativa existe porque a verificação, a apresentação e a demonstração das relações intertextuais precisam considerar o texto na sua forma final. Este trabalho visar contribuir para o estudo das relações intertextuais aplicadas aos textos bíblicos tanto propondo uma clara conceituação de intertextualidade quanto apresentando os critérios de classificação de suas manifestações, bem como deseja verificar que existem relações intertextuais específicas entre Ex 32,1-6 e 1 Rs 12,26-33 e ampliar o horizonte dessas relações intertextuais a todos os versos dos textos de Ex 32,1-6 e 1 Rs 12,26-33. / [en] Aaron s and Jeroboam s Calves: An Intertextuality Verification Analyzing Exodus 32,1-6 and I Kings 12,26-33 has the purpose not only to verify the existence of a broad intertextuality relations between Exodus 32,1-6 and I Kings 12,26-33 but also to present and demonstrate how this intertextuality relation occurs. This thesis is based using the synchronic method of narrative analysis. The reason to use narrative analysis is because the verification in how the text is presented and demonstrated has to consider the text itself in its final form. This work is focused to shad light in the study of intertextuality relations to or deriving meaning applied to the biblical texts not only proposing a clear concept and thesis but also to present the criteria of classification and manifestation as well. Verifying that there are interrelationships in both texts between Exodus 32,1-6 and I Kings 12,26-33 and to broaden the perspective in these intertextuality to every single verses in Exodus 32,1-6 and I Kings 12,26-33. / [it] I vitelli di Aronne e Geroboamo: Una verifica del rapporto intertestuale tra Es 32, 1-6 e 1 Re 12,26-33 ha come oggetto tanto verificare l esistenza dei vari rapporti intertestuali tra i passaggi di Es 32,1-6 e 1 Re 12,26-33 quanto presentare e dimostrare come si manisfesta questa intertestualità. Questa tesi usa il metodo sincronico dell analise narrativa. La necessità di lavorare con il metodo sincronico dell analise esiste perché la verifica, la presentazione e la dimostrazione dei rapporti intertestuali hanno bisogno di considerare il testo nella sua forma finale. Questo lavoro si rivolge a contribuire con lo studio dei rapporti intertestuali applicati ai testi biblichi tanto al proporre un chiaro concetto di intertestualità quanto al presentare i criteri di classificazione delle sue manifestazioni cosí come desidera verificare che ci sono rapporti intertestuali specifichi tra Es 32, 1-6 e Re 12,26-33 e ampliare l orizzonte di questi rapporti intertestuali a tutti i versi dei testi di Es 32,1-6 e 1 Re 12,26-33.

Resumo: Exopolissacarídeos do tipo β-glucanas são polímeros produzidos por uma grande variedade de microrganismos e podem possuir diferentes propriedades físicas, químicas e aspectos estruturais. Esses biopolímeros apresentam atividades biológicas interessantes (antitumor, antiviral, anticoagulante) e aplicações comerciais como produtos em alimentos, cosméticos e farmacêuticos. Entretanto, para a aplicação dessas moléculas, é necessário primeiramente o conhecimento de suas estruturas químicas. Assim, o objetivo deste trabalho foi a produção, caracterização química de quatro exopolissacarideos (EPSGRAVIOLA, EPSMANGA, EPSPINHA e EPSLARANJA) de isolados de Botryosphaeria obtidos de frutas tropicais em decomposição e crescidos em sacarose como única fonte de carbono, determinando o melhor EPS para realizar testes de atividade anticoagulante. A homogeneidade de cada EPS foi determinada por cromatografia de filtração em gel, os quais eluíram como um único pico. Hidrólise ácida total e análise por HPAEC/PAD mostrou glucose como constituinte básico. Dados de metilação e RMN de 13C indicaram que os EPSMANGA, EPSPINHA e EPSLARANJA são glucanas lineares unidas por ligações do tipo β(1®6) e o EPSGRAVIOLA é uma glucana com ligações β(1®3) e com ramificações em C-6 de resíduos glucopiranosídicos. O espectro de FT-IR mostrou uma banda em 891 cm-1, e a espectroscopia de 13C NMR mostrou que todas as ligações eram do tipo β. Estudos realizados com o corante Vermelho Congo indicaram que os EPS possuem conformação em tripla hélice. O EPSLARANJA, uma b- D-(1®6)-glucana, foi submetido a sulfatação visando induzir a atividade anticoagulante e melhorar a solubilidade da molécula em solução, importante para a atividade biológica. Espectros de FT-IR mostraram bandas em 808 and 1252 cm-1, indicando a entrada dos grupos sulfato e as análises de RMN de 13C mostraram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Exopolysaccharides (EPS) as β-glucans are polymers produced by a great variety of microorganisms and can possess different physical and chemical properties, and structural features. These biopolymers having interesting biological activities (antitumor, anti-viral, anticoagulant), and commercial applications in foods, cosmetics and pharmaceutical products. However, for the applications of these macromolecules, it is first necessary to understand their chemical structures. Therefore the goal of that study was the production, chemical characterization and biological activity of four exopolysaccharides (EPSGRAVIOLA, EPSMANGO, EPSPINHA and EPSORANGE) obtained from Botryosphaeria strains isolated from rotting tropical fruit grown on sucrose as carbon and the best EPS was used for the anticoagulant activity The homogeneity of each EPS was determined by gel filtration chromatography, which was eluted as a single peak. Total acid hydrolysis and HPAEC/PAD analysis of each EPS yielded only glucose. Data from methylation analysis and 13C NMR spectroscopy indicated that the EPSMANGO, EPSPINHA and EPSORANGE consisted of a linear chain of (1-6)- linked glucopyranosyl residues and EPSGRAVIOLA consisted of a main chain of glucopyranosyl (1-3) linkages substituted at O-6. FTIR spectra showed one band at 891 cm-1, and 13C NMR spectroscopy showed that all glucosidic linkages were of the β-configuration. Dye-inclusion studies with Congo Red indicated that each EPS existed in a triple-helix conformational state. The EPSORANGE, a β-(1®6)- D-glucan was submitted to a sulfation to induce anticoagulant activity and also to make this EPS more soluble, which is in favor to its biological action. The FT-IR spectrum showed bands at 808 and 1252 cm-1 indicating insertion of sulfonyl groups and the 13C NMR analysis showed that the sulfonyl groups were inserted mainly in C-4 of the b(1®6)-D-glucan... (Complete abstract click electronic access below) / Orientador: Roberto da Silva / Coorientador: Maria de Lourdes Corradi da Silva / Banca: Gabriela Alves Macêdo / Banca: Maria Inês Rezende / Banca: Jonas Contiero / Banca: Eleonora Cano Carmona / Doutor

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The Near Earth Asteroid Rendezvous (NEAR) satellite will travel to the asteroid 433 Eros, arriving there early in 1999, and orbit the asteroid for 1 year taking measurements that will map the surface features and determine its elemental composition. NEAR is the first satellite to use the rate-1/6 convolutional encoding on its telemetry downlink. Due to the scarcity and complexity of full decoders, APL designed and built a less capable but inexpensive version of the decoder for use in the integration, test, and prelaunch checkout of the rate-1/6 encoder. This paper describes the rationale for the design, how it works, and the features that are included.

As doenças associadas ao circovírus suíno (DACS) causam impacto econômico negativo nos sistemas de criação de suínos no mundo todo. As perdas incluem tratamento da doença, mortalidade, bem como diminuição no desempenho dos animais. Uma das manifestações mais relevantes das DACS é a síndrome multissistêmica do definhamento dos suínos (SMDS). O principal agente patogênico na causa da SMDS é o circovírus suíno tipo 2 (PCV2), no entanto, estudos observacionais e experimentais demonstraram que outros agentes estão envolvidos na patogênese e manifestação dos sinais clínicos. O sequenciamento de alto desempenho aliado a metagenômica são ferramentas que tornam possível a identificação da microbiota total de uma determinada amostra, independentemente de cultivo dos microrganismos. Visando contribuir para o conhecimento dos possíveis vírus envolvidos na SMDS, o presente trabalho realizou o sequenciamento genético de alto desempenho de soros de suínos e posterior análise do metagenoma resultante. Foram utilizadas amostras de soro coletadas em 2008, de 16 suínos com sinais clínicos da SMDS, entre 80 e 100 dias de idade, em uma granja no interior do Rio Grande do Sul. Os dados revelaram sequências virais de PCV2, parvovírus suíno tipo 1 a 6 (PPV1-6), torque teno vírus de suínos (TTSuV) tipo 1b, k2a e k2b e vírus de DNA circular de fita simples codificador de proteína associada a replicação (CRESS). A ocorrência de PCV2, PPV1-5 e TTSuV já foi descrita em suínos com SMDS, portanto este estudo reforça resultados anteriores. O PPV6 foi recentemente descrito na China, Europa e Estados Unidos, e os estudos não relacionaram o vírus com nenhuma doença específica de suínos. Os CRESS já foram identificados em todos os continentes, em vários tipos de amostras, incluindo fezes de suínos, mas sem nenhuma conexão com doenças de animais. Portanto, este é o primeiro relato de PPV6 e CRESS em suínos apresentando sinais de SMDS. Porém estudos posteriores são necessários para poder atribuir relação entre PPV6 e CRESS no desenvolvimento da SMDS. / Porcine circovirus associated disease (PCVAD) is one of the causes of negative economic impact on pig farming systems described worldwide. Losses include expenditures with treatment, increased mortality rates, and decreased productivity. One of the most relevant manifestations of PCVAD is the post-weaning multisystemic wasting syndrome (PMWS). The main pathogen present in PMWS is porcine circovirus type 2 (PCV2). However, observational and experimental studies have shown that other agents may be involved in the pathogenesis and clinical manifestation. High-throughput sequencing combined with metagenomics analyses make it possible to identify the total microbiota in a given sample, regardless of microorganism culture. In order to contribute to the knowledge of the viruses involved in PMWS, the present study carried out the high-throughput sequencing of swine sera and subsequent analysis of the resulting metagenome. Sixteen serum samples collected in 2008 on a farm in Rio Grande do Sul, from 80 and 100 days old pigs with clinical signs of PMWS, were examined. Data revealed viral sequences of PCV2, porcine parvovirus type 1 through 6 (PPV1-6), torque teno sus virus (TTSuV) types 1b, k2a and k2b and circular replication-associated protein (Rep) encoding single-stranded (CRESS) DNA viruses. The occurrences of PCV2, PPV1-5 and TTSuV have already been described in pigs with PMWS, so this study reinforces previous results. PPV6 was recently described in China, Europe and the United States, and the studies did not correlate the virus to any specific disease. CRESS DNA viruses have been identified on all continents in various types of samples, including swine feces, but without any connection to animal diseases. The present study is the first report of PPV6 and CRESS in pigs presenting PMWS signals. However, further studies are necessary to be able to attribute the relationship between PPV6 and CRESS in the development of SMDS.

<p>Methylglyoxal (MG) is a reactive glucose metabolite and a known causative factor for hypertension and diabetes. Hydrogen sulfide (H₂S), on the other hand, is a gasotransmitter with multifaceted physiological functions, including anti-oxidant and vasodilatory properties. The present study demonstrates that MG and H₂S can interact with and modulate each other's functions. Upon <i>in vitro</i> incubations, we found that MG and H₂S can directly interact to form three possible MG-H₂S adducts. Furthermore, the endogenous production level of MG or H₂S was significantly reduced in a concentration-dependent manner in rat vascular smooth muscle cells (A-10 cells) treated with NaHS, a H₂S donor, or MG, respectively. Indeed, MG-treated A-10 cells exhibited a concentration-dependent down-regulation of the protein and activity level of cystathionine &gamma;-lyase (CSE), the main H₂S-generating enzyme in the vasculature. Moreover, H₂S can induce the inhibition of MG-generated ROS production in a concentration-dependent manner in A-10 cells. In 6-22 week-old CSE knockout male mice (CSE^-/-), mice with lower levels of vascular H₂S, we observed a significant elevation in MG levels in both plasma and renal extracts. Renal triosephosphates were also significantly increased in the 6-22 week-old CSE^-/- mice. To identify the source of the elevated renal MG levels, we found that the activity of fructose-1,6-bisphosphatase (FBPase), the rate-limiting enzyme in gluconeogenesis, was significantly down-regulated, along with lower levels of its product (fructose-6-phosphate) and higher levels of its substrate (fructose-1,6-bisphosphate) in the kidney of 6-22 week-old CSE^-/- mice. We have also observed lower levels of the gluconeogenic regulator, peroxisome proliferator-activated receptor-&gamma; coactivator (PGC)-1&alpha;, and its down-stream targets, FBPase-1 and -2, phosphoenolpyruvate carboxykinase (PEPCK), and estrogen-related receptor (ERR)&alpha; mRNA expression levels in renal extracts from 6-22 week-old CSE^-/- mice. Likewise, FBPase-1 and -2 mRNA levels were also significantly down-regulated in aorta tissues from 14-16 week-old CSE^-/- mice. Administration of 30 and 50 &#x00B5;M NaHS induced a significant increase in FBPase-1 and PGC-1&alpha; in rat A-10 cells. We have also observed a significant up-regulation of PEPCK and ERR&alpha; mRNA expression levels in 50 &#x00B5;M NaHS-treated A-10 cells, further confirming the involvement of H₂S in regulating the rate of gluconeogenesis and MG formation. Overall, this unique study demonstrates the existence of a negative correlation between MG and H₂S in the vasculature. Further elucidation of this cross-talk phenomenon between MG and H₂S could lead to more elaborate and effective therapeutic regimens to combat metabolic syndrome and its related health complications.</p>

<p>Methylglyoxal (MG) is a reactive glucose metabolite and a known causative factor for hypertension and diabetes. Hydrogen sulfide (H₂S), on the other hand, is a gasotransmitter with multifaceted physiological functions, including anti-oxidant and vasodilatory properties. The present study demonstrates that MG and H₂S can interact with and modulate each other's functions. Upon <i>in vitro</i> incubations, we found that MG and H₂S can directly interact to form three possible MG-H₂S adducts. Furthermore, the endogenous production level of MG or H₂S was significantly reduced in a concentration-dependent manner in rat vascular smooth muscle cells (A-10 cells) treated with NaHS, a H₂S donor, or MG, respectively. Indeed, MG-treated A-10 cells exhibited a concentration-dependent down-regulation of the protein and activity level of cystathionine &gamma;-lyase (CSE), the main H₂S-generating enzyme in the vasculature. Moreover, H₂S can induce the inhibition of MG-generated ROS production in a concentration-dependent manner in A-10 cells. In 6-22 week-old CSE knockout male mice (CSE^-/-), mice with lower levels of vascular H₂S, we observed a significant elevation in MG levels in both plasma and renal extracts. Renal triosephosphates were also significantly increased in the 6-22 week-old CSE^-/- mice. To identify the source of the elevated renal MG levels, we found that the activity of fructose-1,6-bisphosphatase (FBPase), the rate-limiting enzyme in gluconeogenesis, was significantly down-regulated, along with lower levels of its product (fructose-6-phosphate) and higher levels of its substrate (fructose-1,6-bisphosphate) in the kidney of 6-22 week-old CSE^-/- mice. We have also observed lower levels of the gluconeogenic regulator, peroxisome proliferator-activated receptor-&gamma; coactivator (PGC)-1&alpha;, and its down-stream targets, FBPase-1 and -2, phosphoenolpyruvate carboxykinase (PEPCK), and estrogen-related receptor (ERR)&alpha; mRNA expression levels in renal extracts from 6-22 week-old CSE^-/- mice. Likewise, FBPase-1 and -2 mRNA levels were also significantly down-regulated in aorta tissues from 14-16 week-old CSE^-/- mice. Administration of 30 and 50 &#x00B5;M NaHS induced a significant increase in FBPase-1 and PGC-1&alpha; in rat A-10 cells. We have also observed a significant up-regulation of PEPCK and ERR&alpha; mRNA expression levels in 50 &#x00B5;M NaHS-treated A-10 cells, further confirming the involvement of H₂S in regulating the rate of gluconeogenesis and MG formation. Overall, this unique study demonstrates the existence of a negative correlation between MG and H₂S in the vasculature. Further elucidation of this cross-talk phenomenon between MG and H₂S could lead to more elaborate and effective therapeutic regimens to combat metabolic syndrome and its related health complications.</p>

As doenças associadas ao circovírus suíno (DACS) causam impacto econômico negativo nos sistemas de criação de suínos no mundo todo. As perdas incluem tratamento da doença, mortalidade, bem como diminuição no desempenho dos animais. Uma das manifestações mais relevantes das DACS é a síndrome multissistêmica do definhamento dos suínos (SMDS). O principal agente patogênico na causa da SMDS é o circovírus suíno tipo 2 (PCV2), no entanto, estudos observacionais e experimentais demonstraram que outros agentes estão envolvidos na patogênese e manifestação dos sinais clínicos. O sequenciamento de alto desempenho aliado a metagenômica são ferramentas que tornam possível a identificação da microbiota total de uma determinada amostra, independentemente de cultivo dos microrganismos. Visando contribuir para o conhecimento dos possíveis vírus envolvidos na SMDS, o presente trabalho realizou o sequenciamento genético de alto desempenho de soros de suínos e posterior análise do metagenoma resultante. Foram utilizadas amostras de soro coletadas em 2008, de 16 suínos com sinais clínicos da SMDS, entre 80 e 100 dias de idade, em uma granja no interior do Rio Grande do Sul. Os dados revelaram sequências virais de PCV2, parvovírus suíno tipo 1 a 6 (PPV1-6), torque teno vírus de suínos (TTSuV) tipo 1b, k2a e k2b e vírus de DNA circular de fita simples codificador de proteína associada a replicação (CRESS). A ocorrência de PCV2, PPV1-5 e TTSuV já foi descrita em suínos com SMDS, portanto este estudo reforça resultados anteriores. O PPV6 foi recentemente descrito na China, Europa e Estados Unidos, e os estudos não relacionaram o vírus com nenhuma doença específica de suínos. Os CRESS já foram identificados em todos os continentes, em vários tipos de amostras, incluindo fezes de suínos, mas sem nenhuma conexão com doenças de animais. Portanto, este é o primeiro relato de PPV6 e CRESS em suínos apresentando sinais de SMDS. Porém estudos posteriores são necessários para poder atribuir relação entre PPV6 e CRESS no desenvolvimento da SMDS. / Porcine circovirus associated disease (PCVAD) is one of the causes of negative economic impact on pig farming systems described worldwide. Losses include expenditures with treatment, increased mortality rates, and decreased productivity. One of the most relevant manifestations of PCVAD is the post-weaning multisystemic wasting syndrome (PMWS). The main pathogen present in PMWS is porcine circovirus type 2 (PCV2). However, observational and experimental studies have shown that other agents may be involved in the pathogenesis and clinical manifestation. High-throughput sequencing combined with metagenomics analyses make it possible to identify the total microbiota in a given sample, regardless of microorganism culture. In order to contribute to the knowledge of the viruses involved in PMWS, the present study carried out the high-throughput sequencing of swine sera and subsequent analysis of the resulting metagenome. Sixteen serum samples collected in 2008 on a farm in Rio Grande do Sul, from 80 and 100 days old pigs with clinical signs of PMWS, were examined. Data revealed viral sequences of PCV2, porcine parvovirus type 1 through 6 (PPV1-6), torque teno sus virus (TTSuV) types 1b, k2a and k2b and circular replication-associated protein (Rep) encoding single-stranded (CRESS) DNA viruses. The occurrences of PCV2, PPV1-5 and TTSuV have already been described in pigs with PMWS, so this study reinforces previous results. PPV6 was recently described in China, Europe and the United States, and the studies did not correlate the virus to any specific disease. CRESS DNA viruses have been identified on all continents in various types of samples, including swine feces, but without any connection to animal diseases. The present study is the first report of PPV6 and CRESS in pigs presenting PMWS signals. However, further studies are necessary to be able to attribute the relationship between PPV6 and CRESS in the development of SMDS.

As doenças associadas ao circovírus suíno (DACS) causam impacto econômico negativo nos sistemas de criação de suínos no mundo todo. As perdas incluem tratamento da doença, mortalidade, bem como diminuição no desempenho dos animais. Uma das manifestações mais relevantes das DACS é a síndrome multissistêmica do definhamento dos suínos (SMDS). O principal agente patogênico na causa da SMDS é o circovírus suíno tipo 2 (PCV2), no entanto, estudos observacionais e experimentais demonstraram que outros agentes estão envolvidos na patogênese e manifestação dos sinais clínicos. O sequenciamento de alto desempenho aliado a metagenômica são ferramentas que tornam possível a identificação da microbiota total de uma determinada amostra, independentemente de cultivo dos microrganismos. Visando contribuir para o conhecimento dos possíveis vírus envolvidos na SMDS, o presente trabalho realizou o sequenciamento genético de alto desempenho de soros de suínos e posterior análise do metagenoma resultante. Foram utilizadas amostras de soro coletadas em 2008, de 16 suínos com sinais clínicos da SMDS, entre 80 e 100 dias de idade, em uma granja no interior do Rio Grande do Sul. Os dados revelaram sequências virais de PCV2, parvovírus suíno tipo 1 a 6 (PPV1-6), torque teno vírus de suínos (TTSuV) tipo 1b, k2a e k2b e vírus de DNA circular de fita simples codificador de proteína associada a replicação (CRESS). A ocorrência de PCV2, PPV1-5 e TTSuV já foi descrita em suínos com SMDS, portanto este estudo reforça resultados anteriores. O PPV6 foi recentemente descrito na China, Europa e Estados Unidos, e os estudos não relacionaram o vírus com nenhuma doença específica de suínos. Os CRESS já foram identificados em todos os continentes, em vários tipos de amostras, incluindo fezes de suínos, mas sem nenhuma conexão com doenças de animais. Portanto, este é o primeiro relato de PPV6 e CRESS em suínos apresentando sinais de SMDS. Porém estudos posteriores são necessários para poder atribuir relação entre PPV6 e CRESS no desenvolvimento da SMDS. / Porcine circovirus associated disease (PCVAD) is one of the causes of negative economic impact on pig farming systems described worldwide. Losses include expenditures with treatment, increased mortality rates, and decreased productivity. One of the most relevant manifestations of PCVAD is the post-weaning multisystemic wasting syndrome (PMWS). The main pathogen present in PMWS is porcine circovirus type 2 (PCV2). However, observational and experimental studies have shown that other agents may be involved in the pathogenesis and clinical manifestation. High-throughput sequencing combined with metagenomics analyses make it possible to identify the total microbiota in a given sample, regardless of microorganism culture. In order to contribute to the knowledge of the viruses involved in PMWS, the present study carried out the high-throughput sequencing of swine sera and subsequent analysis of the resulting metagenome. Sixteen serum samples collected in 2008 on a farm in Rio Grande do Sul, from 80 and 100 days old pigs with clinical signs of PMWS, were examined. Data revealed viral sequences of PCV2, porcine parvovirus type 1 through 6 (PPV1-6), torque teno sus virus (TTSuV) types 1b, k2a and k2b and circular replication-associated protein (Rep) encoding single-stranded (CRESS) DNA viruses. The occurrences of PCV2, PPV1-5 and TTSuV have already been described in pigs with PMWS, so this study reinforces previous results. PPV6 was recently described in China, Europe and the United States, and the studies did not correlate the virus to any specific disease. CRESS DNA viruses have been identified on all continents in various types of samples, including swine feces, but without any connection to animal diseases. The present study is the first report of PPV6 and CRESS in pigs presenting PMWS signals. However, further studies are necessary to be able to attribute the relationship between PPV6 and CRESS in the development of SMDS.

Tal i bråkform är en viktig del av den svenska läroplanen, ett räknesätt som många elever har svårt att förstå. Lärare behöver vara insatta i olika undervisningsmetoder för tal i bråk-form, för att skapa bra undervisningstillfällen för elever. Detta behövs speciellt för elever i matematiksvårigheter. Undervisning ska anpassas utifrån elevers behov, vilket sker bäst när lärare känner till undervisningsmetoder som är fördelaktiga för elevers inlärning. Denna litte-raturstudie presenterar därför 15 undervisningsmetoder som forskning konstaterar som fördel-aktiga för undervisning om tal i bråkform för elever i matematiksvårigheter. Undervisnings-metoderna skiljer sig åt och är fördelaktiga på olika sätt. Undervisningsmetoderna passar också olika bra beroende på elevers tidigare kunskaper. Samtliga undervisningsmetoder för-klaras för att ge en tydlig bild av hur de kan bidra till fördelaktiga inlärningstillfällen för ele-ver i matematiksvårigheter. / Fractions is an important part of the Swedish curriculum, which many students have diffi-culties understanding. Teachers need to be familiar with different teaching methods for frac-tions to create good teaching opportunities for students. Especially for students with mathe-matic difficulties. Teaching should be adapted based on students’ needs, which happens best when teachers know which teaching methods that are beneficial for students’ learning. This literature study therefore presents 15 teaching methods that research finds to be advantageous for teaching fractions to students in mathematical difficulties. The teaching methods differ and are advantageous in different ways. The teaching methods also suit the students differ-ently depending on the students’ previous knowledge. All 15 teaching methods are explained to give a clear picture of how they can contribute to advantageous learning opportunities for students with mathematical difficulties.