22 research outputs found
Chasing the cuprates with dilatonic dyons
No full textAbstract: Magnetic field and momentum dissipation are key ingredients in describing condensed matter systems. We include them in gauge/gravity and systematically explore the bottom-up panorama of holographic IR effective field theories based on bulk EinsteinMaxwell Lagrangians plus scalars. The class of solutions here examined appears insufficient to capture the phenomenology of charge transport in the cuprates. We analyze in particular the temperature scaling of the resistivity and of the Hall angle. Keeping an open attitude, we illustrate weak and strong points of the approach
Coexistence of two vector order parameters: A holographic model for ferromagnetic superconductivity
No full textWe study a generalization of the standard holographic p-wave superconductor featuring two interacting vector order parameters. Basing our argument on the symmetry and linear response properties of the model, we propose it as a holographic effective theory describing a strongly coupled ferromagnetic superconductor. We show that the two order parameters undergo concomitant condensations as a manifestation of an intrinsically interlaced charge/spin dynamics. Such intertwined dynamics is confirmed by the study of the transport properties. We characterize thoroughly the equilibrium and the linear response (i.e. optical conductivity and spin susceptibility) of the model at hand by means of a probe approximation analysis. Some insight about the effects of backreaction in the normal phase can be gained by analogy with the s-wave unbalanced holographic superconductor. © 2014 The Author(s).SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Nutritive value of forages and diets in some small-scale dairy farms in Kiambu County, Kenya in the short rains season
No full textSixteen selected small-scale dairy farms were investigated in Kiambu County (Kenya) during the short rains season to develop a snapshot of the types of rations fed, milk yields obtained and sources of fodder. On average farmers had 1 ha of land and 2.2 lactating cows yielding 8.93 kg milk/cow/d with feed intake of 10.5 kg DM/d. Only 35% of feed consumed was produced on farm. Boma Rhodes grass hay and green Napier grass were the main forage components (37.9 and 28.3% of total DM). Protein forages used were the herbaceous legumes lucerne and desmodium (19.9 and 15.9% CP, respectively) and leguminous shrubs (Leucaena, Calliandra and Sesbania with 21.1% CP and 43.4% aNDFom, on average). Grasses had higher aNDFom digestibility (47.1%) than legumes (39.7%). Napier grass, Boma Rhodes grass, lucerne and desmodium had fiber digestibility of 51.9, 48.6, 46.8 and 32.6%, respectively. The energy and protein balances (actual vs. requirements) of the cows were on average-19.3 and-16.4%, respectively, indicating that cows utilized body tissues to produce the levels of milk obtained. Mutiple correspondence analysis showed that a milk yield higher than 9.1 kg/d was associated with a level of Boma Rhodes grass 5 kg DM/d, concentration of non fibrous carbohydrates in the diet 22.0% (DM basis), concentrate level >2.63 kg/cow/d and CP% in the ration >9.1%. To improve milk yields during this season farmers should harvest grass forage at a younger age, include leguminous forage in the diets and increase the level of concentrates fed. These strategies should be demonstrated on farms to show possible benefits
Laparoscopic treatment for an inguinal Richter's hernia: an unusual indication in case of acute small bowel obstruction
No full textPeritoneal encapsulation with an abnormal vessel in a band causing small bowel obstruction: a rare entity
No full textA ALBA e a luta pela hegemonia no continente americano: uma topologia do discurso bolivariano
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas. Programa de Pós-graduação em Sociologia PolíticaO objetivo da dissertação é analisar o movimento bolivariano, liderado pela Venezuela, enquanto projeto de construção de uma nova hegemonia na América Latina e o Caribe. Tal projeto se constrói discursivamente em oposição à histórica hegemonia pan-americana liderada pelos Estados Unidos (EUA). Para isso é estudada a ALBA (Aliança Bolivariana para os Povos de nossa América) como organização internacional que facilita a alineação de países e sociedades latino-americanos em relação ao movimento bolivariano, gerando novas modalidades de construção de sentido, assim como novas vias e regras de relacionamento internacional. A pesquisa analisa os discursos de mandatários nas reuniões de Cúpula da ALBA, e, apelando à teoria do discurso de Ernesto Laclau, identifica nesse conjunto os três passos previstos pelo autor na configuração de um desafio hegemônico: (1) o estabelecimento de um antagonismo face ao imperialismo dos EUA que é identificado como o poder hegemônico institucionalizado, e a dicotomização do espaço social americano através da construção de uma fronteira entre esse poder e o resto da comunidade (América Latina e o Caribe); (2) a articulação contingente entre diversas demandas sociais, características da América Latina e do Caribe, cuja insatisfação é atribuída ao imperialismo dos EUA; e (3) a formação de um campo popular, através da expressão positiva dessas demandas numa nova identidade, no caso a identidade bolivariana. A pesquisa conclui que o movimento bolivariano consegue gerar elementos para permitir uma nova lógica de construção de sentido, configurando assim estruturalmente um campo de luta pela hegemonia. Porém, também são destacados vários problemas nessa tarefa, especialmente ligados à identificação de diversas unidades com o bolivarianismo.The dissertation research the Bolivarian Movement, headed by Venezuela, as a new hegemonic project, still under construction, at Latin America and the Caribbean. This hegemonic project is discursively constructed in opposition to the historic Pan American hegemony, led by the U.S. In this way, the Bolivarian Alliance for the Peoples of Our America (ALBA) is approached as an international organization that seeks to align the Latin American countries and societies behind the Bolivarian Movment. The ALBA generates new ways of sense-making, as well as new norms of international relations. The research analyzes the speeches at the ALBA's presidential summits, using the Ernesto Laclau's Discourse Theory, and identifying the three steps proposed by this author to the hegemonic construction: Firstly, the establishment of an antagonism against U.S. imperialism and the dicotomization of the hemispheric social space, through the definition of a boundary between the powerful country and the rest of continental community (Latina America and the Caribe). Secondly, the contingent articulation of a variety of social demands, which dissatisfaction are ascribed to the U.S. imperialism. Thirdly, the formation of a new popular field, through the positive expression on a new identity of this unified set of demands, in this case the Bolivarian identity. The dissertation concludes that the Bolivarian movement manages a new logic of sense-making, and therefore places the hegemonic struggle in a new structural field. However, it also identified some problems on this task, particularly in the difficulty to construct a Bolivarian identity shared by various social unities (countries, societies and social sectors)
Thrombotic complication in Covid19 non hospitalized patients: an underestimated phenomenon?
No full textIntro Thrombotic complications are quite frequent during SARS-CoV2 infection, especially during severe disease and in hospitalized patients. The incidence in mild disease is not clear and probably few cases have been identified. Case report We reported a case of a 60-year-old man with no previous history admitted in our unit for splenic infarct and a floating clot into the descending aorta without signs of severe disease. Discussion Several mechanisms to clarify prothrombotic state have been described and the exact prevalence of thromboembolic phenomenon is probably underestimated. There is no consensus about the treatment and the indication to prevent these complications in non-hospitalized patients. Conclusion Thrombotic events should be suspected also in fit patients with previous or actual symptoms suggestive for Covid 19 infection. Further analysis should be performed to stratify the risk in non hospitalized patients and the indication for prophylactic treatment
Composite Fermions with spin at ν = 1/2
No full textThis is the author accepted manuscript. The final version is available from IOS press via the DOI in this record.The model of Composite Fermions for describing interacting electrons in two dimensions in the presence of a magnetic field is described. In this model, charged Fermions are combined with an even number of magnetic flux quanta in such a way that the external magnetic field is compensated on the average for half filling of Landau levels and the interaction is incorporated into an effective mass of the new composite particles. The fluctuations of the Chern-Simons gauge field, which describes formally the flux attachment, induce new interactions between the Composite Fermions. The effective interaction is investigated with particular emphasis on the role of the electron spin at filling factor . For a system with equal numbers of spin-up and spin-down electrons it is found that the dominant effective interaction is attractive in the spin-singlet channel. This can induce a ground state consisting of Cooper pairs of Composite Fermions that is separated from the excited states by a gap. The results are used to understand recent spin polarization measurements done in the region of the Fractional Quantum Hall Effect at different constant filling factors.Acknowledgment This work has been supported by the European Union via the TMR
and RTN programmes (FMRX-CT98-0180, HPRN-CT2000-00144), by the Deutsche
Forschungsgemeinschaft within the Schwerpunkt “Quanten-Hall-Effekt” of the Universit¨at
Hamburg, and by the Italian MURST via PRIN00
Rotulagem, qualidade e segurança biológica de alimentos para animais de companhia e seu impacto na saúde
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Ciência dos Alimentos, Florianópolis, 2013.Nas últimas décadas houve um aumento considerável na comercialização de alimentos para animais de companhia. Com foco na garantia desses alimentos, o presente trabalho obteve dados sobre o perfil qualitativo e de segurança de produtos comercializados em diferentes continentes, relacionando a influência de contaminantes biológicos presentes nos alimentos com possíveis danos a saúde animal. As etapas iniciais de desenvolvimento e obtenção de dados foram baseadas na certificação de concordância das informações descritas na rotulagem com a legislação vigente, além da verificação da veracidade das informações nutricionais do produto final embalado. Com relação à adequação de layouts de alimentos secos para cães comercializados no Brasil, 100% das amostras estavam em discordância com as exigências estabelecidas em lei. Já na verificação da veracidade dos níveis de garantia nutricional declarados na rotulagem de alimentos destinados a cães e gatos, 44% não correlacionaram os níveis nutricionais presente no alimento com os níveis de garantia estabelecidos e 36% das amostras estavam em desacordo com níveis nutricionais mínimos preconizados para a manutenção e desenvolvimento animal. Indicadores de qualidade e segurança alimentar também foram avaliados com o intuito de investigar a presença de contaminantes biológicos, incluindo seus metabólitos tóxicos até então não discutidos em alimentação destinada a animais de companhia (como sujidades leves e formação de aminas bioativas). No estudo de indicadores de condições higiênico-sanitárias de amostras de alimentos secos para cães e gatos, as contagens totais (cargas bacterianas e fúngicas) estavam dentro de valores considerados aceitáveis para consumo. No entanto, fungos micotoxigênicos foram isolados: gênero Aspergillus (A. parasiticus, A. niger e A. ochraceus) e Penicillium (P. expansum). A presença de agentes bacterianos em alimentos para cães e gatos (ricos em proteínas) pode favorecer a produção de aminas bioativas (biogênicas e poliaminas), importantes indicadores das condições higiênico-sanitárias aplicadas durante as etapas de produção do alimento final, assim como podem ser tóxicas à saúde animal. A principal amina biogênica detectada foi a histamina10(96%), seguida pelas putrescina e cadaverina (92%). À partir do conhecimento do perfil qualitativo biológico dos alimentos secos, esses dados foram correlacionados com diferentes formas de exposição do produto nos pontos de venda (embalagens abertas e/ou lacradas) e riscos associados a segurança alimentar. Em avaliação realizada para verificar as condições de comercialização em embalagens abertas (à granel) de alimentos completos para cães e pássaros, essa forma de exposição proporcionou aumento nos teores de umidade e atividade de água, favorecendo o crescimento de fungos toxigênicos e micotoxinas. A presença de insetos, ácaros e pêlos de roedores no produto final também devem ser considerados como importantes veiculadores desses agentes biológicos (bactérias, fungos e micotoxinas). Na avaliação de alimentos para cães comercializados em embalagens lacradas, 87% das amostras continham algum tipo de sujidade biológica leve (fragmentos de insetos e ácaros). Com relação aos ensaios micológicos, foi observado contaminação em todas as amostras, com presença dos gêneros Aspergillus (80,6%) e Penicillium (54,8%), e contaminação por fumonisinas em 32,2% das amostras. A partir dos diversos dados, foi possível obter subsídios para futuras discussões e revisões sobre os padrões legais vigentes e limites de tolerância estabelecidos, garantindo a saúde dos animais consumidores. Lembrando que a dieta de animais de companhia é baseada em somente um tipo de alimento, o qual consumido diariamente, amplifica a exposição a possíveis contaminantes biológicos presente na dieta.Abstract : A considerable increase in the marketing of pet foods has been observed in recent decades. With a focus on ensuring these foods, this study obtained data on the qualitative and safety of products marketed in different continents, relating the influence of biological contaminants in foods with possible damage to animal health. The initial stages of development and obtaining data were based on the labeling information and certification of regulation compliance, beyond to check the accuracy of the nutritional information of the final packaged product. Regarding the adequacy of layouts dry dog food sold in Brazil, 100 % of the samples were not in accordance with the requirements established by regulation. Respect the check the accuracy of the guarantee levels declared in nutrition labeling of dogs and cats foods, 44 % did not correlate the levels present in food with nutritional levels established warranty and 36 % of the samples were in disagreement with minimum nutritional levels recommended for the maintenance and animal development. The food quality and safety indicators were also evaluated in order to investigate the presence of biological contaminants, including toxic metabolites not previously discussed on pet food (such as light filth and bioactive amines formation). In the study of indicators of hygienic-sanitary conditions of dogs and cats dry food samples, the total counts (bacterial and fungal loads) values were considered acceptable for animal consumption. However, mycotoxigenic fungi were isolated: Aspergillus (A. parasiticus, A. niger and A. ochraceus) and Penicillium (P. expansum). The presence of bacterial agents in dogs and cats food (in which are rich in proteins) may favor the bioactive amines formation (biogenic and polyamines), important indicators of the sanitary conditions applied during the final food production, as can be toxic to animal health. The main biogenic amine detected was histamine (96 %), followed by putrescine and cadaverine (92 %). From the knowledge of biological qualitative profile of dry foods, these data were correlated with different forms of product presentation at point of sale (opened packages and/or sealed) and risks associated with food safety. In evaluation performed to check the marketing conditions in opened packages (open bulk bags) of dogs and birds food, this form of exposure12increased the moisture content and water activity, favoring the toxigenic fungi growth and mycotoxins production. The presence of insects, mites and rodents hair in the final product must also be considered important biological agents carrier (bacteria, fungi and mycotoxins). In the evaluation of dog food sold in sealed packages, 87 % of samples contained some sort of biological light filth (as fragments of insects and mites). Respect to the mycological tests, contamination was observed in all samples, with the presence of genera Aspergillus (80.6 %) and Penicillium (54.8 %), and fumonisin contamination in 32.2 % of samples. From the various data, it was possible to obtain a basis for future discussions and reviews on current standards regulation and tolerance limits established, ensuring animal health consumers. Important to mention that the pet animals diet is based on monotype food, which consumed daily, amplifies the potential exposure to biological contaminants present in the diet
P-I snake venom metalloproteinase is able to activate the complement system by direct cleavage of central components of the cascade
No full textBackground Snake Venom Metalloproteinases (SVMPs) are amongst the key enzymes that contribute to the high toxicity of snake venom. We have recently shown that snake venoms from the Bothrops genus activate the Complement system (C) by promoting direct cleavage of C-components and generating anaphylatoxins, thereby contributing to the pathology and spread of the venom. The aim of the present study was to isolate and characterize the C-activating protease from Bothrops pirajai venom. Results Using two gel-filtration chromatography steps, a metalloproteinase of 23 kDa that activates Complement was isolated from Bothrops pirajai venom. The mass spectrometric identification of this protein, named here as C-SVMP, revealed peptides that matched sequences from the P-I class of SVMPs. C-SVMP activated the alternative, classical and lectin C-pathways by cleaving the α-chain of C3, C4 and C5, thereby generating anaphylatoxins C3a, C4a and C5a. In vivo, C-SVMP induced consumption of murine complement components, most likely by activation of the pathways and/or by direct cleavage of C3, leading to a reduction of serum lytic activity. Conclusion We show here that a P-I metalloproteinase from Bothrops pirajai snake venom activated the Complement system by direct cleavage of the central C-components, i.e., C3, C4 and C5, thereby generating biologically active fragments, such as anaphylatoxins, and by cleaving the C1-Inhibitor, which may affect Complement activation control. These results suggest that direct complement activation by SVMPs may play a role in the progression of symptoms that follow envenomation. Author Summary The genus Bothrops inflicts the vast majority of snakebites in Central and South America and is responsible for 90% of snake envenomations in Brazil. Envenomations are characterized by prominent local effects, including edema and necrosis, and by systemic manifestations such as hemorrhage, coagulopathy and acute renal failure. Several components have been isolated from Bothrops venoms, and the snake venom metalloproteinases (SVMPs) are key enzymes contributing to the high toxicity of the venoms. Previously, we analyzed the pro-inflammatory properties of snake venoms from the genus Bothrops and demonstrated that several of them were potent activators of the Complement (C) system. C3a, C4a and C5a were generated in venom-treated sera not only through C-activation but also by direct cleavage of C-components. In the present study, we have isolated and characterized a metalloproteinase from Bothrops pirajai snake venom, named here as C-SVMP, which interferes with all three complement pathways, generating potent pro-inflammatory fragments, such as C3a, C4a and C5a. Our data suggest that C-activation by Bothrops pirajai venom is due to activity of an SVMP, which may play a role in the progression of symptoms that follow envenomation
