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The reaction mechanisms of the two-neutron transfer reaction $^{12}$C($^6$He,$^4$He) have been studied at 30 MeV at the TRIUMF ISAC-II facility using the SHARC charged-particle detector array. Optical potential parameters have been extracted from the analysis of the elastic scattering angular distribution. The new potential has been applied to the study of the transfer angular distribution to the 2$^+_2$ 8.32 MeV state in $^{14}$C, using a realistic 3-body $^6$He model and advanced shell model calculations for the carbon structure, allowing to calculate the relative contributions of the simultaneous and sequential two-neutron transfer. The reaction model provides a good description of the 30 MeV data set and shows that the simultaneous process is the dominant transfer mechanism. Sensitivity tests of optical potential parameters show that the final results can be considerably affected by the choice of optical potentials. A reanalysis of data measured previously at 18 MeV however, is not as well described by the same reaction model, suggesting that one needs to include higher order effects in the reaction mechanism., Comment: 9 pages, 9 figures

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International audience; Background & AimsTreatment of hepatitis C virus (HCV) infection with boceprevir, peginterferon, and ribavirin can lead to anemia, which has been managed by reducing ribavirin dose and/or erythropoietin therapy. We assessed the effects of these anemia management strategies on rates of sustained virologic response (SVR) and safety.MethodsPatients (n = 687) received 4 weeks of peginterferon and ribavirin followed by 24 or 44 weeks of boceprevir (800 mg, 3 times each day) plus peginterferon and ribavirin. Patients who became anemic (levels of hemoglobin approximately ≤10 g/dL) during the study treatment period (n = 500) were assigned to groups that were managed by ribavirin dosage reduction (n = 249) or erythropoietin therapy (n = 251).ResultsRates of SVR were comparable between patients whose anemia was managed by ribavirin dosage reduction (71.5%) vs erythropoietin therapy (70.9%), regardless of the timing of the first intervention to manage anemia or the magnitude of ribavirin dosage reduction. There was a threshold for the effect on rate of SVR: patients who received

Afirmei anteriormente que a repetida constatação de um défice de trabalhos de pesquisa sobre o mar e os pescadores tende a tornar-se um lugar-comum propedêutico das modernas abordagens antropológicas aos universos piscatórios nacionais. Tendo constatado que nas vizinhas Espanha e França – duas grandes potências marítimas e de fortes tradições navais e haliêuticas – também é reportada a mesma ausência não é de crer que Portugal constitua um exemplo isolado no quadro europeu. Neste texto, exploro diversos aspectos de natureza teórica e epistemológica relacionados com este aparente paradoxo.

O município de Mossoró/RN, no Nordeste do Brasil, tem como destaque a criação de caprinos. A toxoplasmose é uma zoonose que é mais patogênico para os caprinos do que para os demais animais de abate. Em caprinos, o protozoário frequentemente é responsável por problemas reprodutivos e perdas econômicas. Com o objetivo de identificar a soroprevalência e os fatores de risco da toxoplasmose em caprinos de propriedades rurais do Município de Mossoró, amostras de soro de 338 animais (320 fêmeas e 18 machos) de 15 unidades produtoras foram testados pelo Ensaio Imunoenzimático (ELISA). Das 15 propriedades, 14 apresentaram animais soropositivos para toxoplasmose, e nestas o total de animais positivos foram de 125 (123 fêmeas e 2 machos), obtendo uma prevalência de 37,0%. Houve uma relação significativa (p

A new full three-body method is introduced to compute the rate of the triple-alpha capture reaction which is the primary source of $^{12}$C in stars. In this work, we combine the Faddeev hyperspherical harmonics and the R-matrix method to obtain a full solution to the three-body $\alpha+\alpha+\alpha$ continuum. Particular attention is paid to the long range effects caused by the pairwise Coulomb interactions. The new rate agrees with the NACRE rate for temperatures greater than 0.07 GK, but a large enhancement at lower temperature is found ($\approx 10^{14}$ at 0.02 GK). Our results are compared to previous calculations where additional approximations were made. We show that the new rate does not significantly change the evolution of stars around one solar mass. In particular, such stars still undergo a red-giant phase consistent with observations, and no significant differences are found in the final white dwarfs., Comment: 5pg, 2 figures, resubmitted

The finite range adiabatic wave approximation provides a practical method to analyze (d,p) or (p,d) reactions, however until now the level of accuracy obtained in the description of the reaction dynamics has not been determined. In this work, we perform a systematic comparison between the finite range adiabatic wave approximation and the exact Faddeev method. We include studies of $^{11}$Be(p,d)$^{10}$Be(g.s.) at $E_p=$5, 10 and 35 MeV; $^{12}$C(d,p)$^{13}$C(g.s.) at $E_d=$7, 12 and 56 MeV and $^{48}$Ca(d,p)$^{49}$Ca(g.s.) at $E_d=$19, 56 and 100 MeV. Results show that the two methods agree within $\approx 5%$ for a range of beam energies ($E_d \approx 20-40$ MeV) but differences increase significantly for very low energies and for the highest energies. Our tests show that ADWA agrees best with Faddeev when the angular momentum transfer is small $\Delta l=0$ and when the neutron-nucleus system is loosely bound., Comment: Phys. Rev. C, accepted

An improved description of single neutron stripping from $^{34,36,46}$Ar beams at 33 MeV/nucleon by a hydrogen target is presented and the dependence on the neutron-proton asymmetry of the spectroscopic factors is further investigated. A finite range adiabatic model is used in the analysis and compared to previous zero range and local energy approximations. Full three-body Faddeev calculations are performed to estimate the error in the reaction theory. In addition, errors from the optical potentials are also evaluated. From our new spectroscopic factors extracted from transfer, it is possible to corroborate the neutron-proton asymmetry dependence reported from knockout measurements., Comment: 7 pages, 3 figures

With the increasing interest in using (d,p) transfer reactions to extract structure and astrophysical information, it is important to evaluate the accuracy of common approximations in reaction theory. Starting from the zero-range adiabatic wave model, which takes into account deuteron breakup in the transfer process, we evaluate the importance of the finite range of the n-p interaction in calculating the adiabatic deuteron wave (as in Johnson and Tandy) as well as in evaluating the transfer amplitude. Our study covers a wide variety of targets, as well as a large range of beam energies. Whereas at low beam energies finite-range effects are small (below 10%), we find these effects to become important at intermediate energies (20 MeV/u) calling for an exact treatment of finite range in the analysis of (d,p) reactions measured at fragmentation facilities., 8 pages, 9 figures and 2 tables, accepted in Physical Review C

Parasitoid Wasp Genomes Parasitoid wasps, which prey on and reproduce in host insect species, play important roles in plant herbivore interactions, and may provide valuable tools in the biological control of pest species. The Nasonia Genome Working Group (p. 343 ; see the news story by Pennisi ) presents the genome of three very closely related species: Nasonia vitripennis, N. giraulti , and N. longicornis . The findings document rapid evolution between a host and endosymbiont that can cause nuclear-cytoplasmic incompatibilities that may affect speciation.

Aspergillus is a large genus, with a complex and ever evolving taxonomy. Section Flavi is one of the most significant sections in the genus. Taxonomy and species identification is subject of great interest for scientists aiming to clarify the species concept and limits within the section. Furthermore, this section comprises both toxigenic and non-toxigenic species/strains, with great interest to biotechnology and food industry. Various genes, namely the rRNA (ITS region), calmodulin and β-tubulin genes, have been widely reported as good markers for Aspergillus species identification, because they are rapid and cost-effective. In the present study, we evaluated the discriminatory power of the ITS region and the calmodulin gene to distinguish closely related taxa within Aspergillus section Flavi. For this purpose, 26 isolates of Aspergillus section Flavi obtained from Portuguese almonds were characterized at various levels: i) phenotypic, regarding various aspects of morphology and physiology; ii) spectral, using MALDI-TOF ICMS to obtain protein fingerprinting; and iii) genotypic, by sequence analysis of a 730 bp segment of the calmodulin gene and a 908 bp segment of the ITS region. For the various methods, dendrograms were created and results were compared. Both genotypic and spectral analyses divided the isolates in 3 groups corresponding to closely related taxa of A. flavus, A. parasiticus and A. tamarii. Except for the ITS region, all sets of analysis positioned 5 of the 26 isolates in two unidentified clades close to A. parasiticus, and divided the A. flavus group in two distinct clades. The phylogenetic analysis of the calmodulin sequences resulted in very similar dendrograms when using various methods of analysis (Neighbor-Joining, Maximum Likelihood, Bayesian Inference), and altering the analytical parameters did not result in significant changes. Furthermore, the genetic dendrograms were strongly supported by the phenotypic and spectral analyses. These results confirm the calmodulin gene as a robust and reliable genomic marker for this group of fungi. The unsolved isolate identifications are currently under further analysis.

Um dos grandes defeitos ocorrentes no pavimento, ao longo de sua vida útil, é o trincamento por fadiga. Este problema, em geral, se inicia na base do revestimento asfáltico e se propaga para a sua superfície. A caracterização das misturas asfálticas, realizada comumente no Brasil, é baseada no número de ciclos que causam a ruptura no ensaio de fadiga. No entanto, tal número não é um parâmetro mecânico, podendo variar para diferentes condições de contorno. O objetivo do presente artigo é identificar parâmetros mecânicos, referentes ao trincamento por fadiga, do compósito asfáltico com agregado sintético de argila calcinada (ASAC). Para tanto, foi utilizado um modelo viscoelástico de dano contínuo, fundamentado em trabalhos de Shapery, Kim e Lee. Os resultados com o compósito estudado (ASAC) mostraram que a perda de rigidez, baseada em uma variável interna de estado, pode ser um critério de fadiga; que o ensaio pode ser realizado para um nível de tensão; a cura de microtrincas durante os períodos de não solicitação da estrutura. One of the major distresses in flexible pavings, throughout its useful life, is the fatigue cracking. This problem, in general, initiates in the base of the asphalt layer and propagates for its surface. The characterization of the asphalt mixtures, carried out in Brazil, is based on the number of cycles that cause the rupture in the fatigue test. However, such number is not a mechanical parameter, varying for different boundary conditions. The objective of the present article is to identify mechanical parameters, referring fatigue cracking, of the asphalt composite with synthetic calcinated clay aggregates (SCCA). To this end, a continuum damage viscoelastic model was used based works from Shapery, Kim and Lee. The results with the composite studied (SCCA) had shown: that the loss of rigidity, based on an internal state variable, can be a fatigue criterion; that the test can be carried through for one stress level; the healing of micro cracks during the rest periods in the structure.

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O presente trabalho de investigação tem como principal objectivo dar um contributo na temática das soluções de melhoramento do comportamento e do reforço de elementos construtivos de terra a partir do estudo biomimético do ninho da andorinha-dos-beirais. Os resultados experimentais obtidos apontam para a existência de polissacarídeos/açucares no material do ninho e que possívelmente são adicionados pela andorinha-dos-beirais durante o processo de construção do ninho.

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A terra é um material natural, ecológico, reciclável e abundante e, como tal, foi sempre e volta agora a ser considerado como sendo um dos materiais/soluções de construção de eleição, com enorme potencial. Na construção tradicional portuguesa encontram-se várias soluções construtivas recorrendo ao uso da terra crua, com uma importante expressão. Este património construído necessita de ser conservado. Neste contexto, o presente trabalho tem como principal objectivo dar um contributo na temática das soluções de melhoramento do comportamento e reforço de elementos construtivos em terra a partir do estudo biomimético de um ninho de andorinha-dos-beirais. De modo a identificar a eventual existência de algum fenómeno de aglutinação ocorrido durante o processo de construção de um ninho de andorinha-dos-beirais, procedeu-se a um trabalho experimental de caracterização a partir de amostras recolhidas em diferentes ninhos encontrados na zona de Vila Real. Para a identificação da composição química inorgânica e mineralógica das amostras recolhidas realizaram-se análises em Scanning Electron Microscopy / Energy Dispersive Spectroscopy (SEM/EDS) e por difracção de raios-X. Para a identificação da composição orgânica das amostras recolhidas foi feita a quantificação colorimétrica do teor de proteínas pelo método de biureto, e do teor de polissacarídeos/açucares pelo método dos açúcares totais. Os resultados experimentais relativos às amostras retiradas dos ninhos quando comparados com resultados similares relativos a amostras de argila recolhidas na mesma zona de origem dos ninhos, são muito semelhantes, destacando-se apenas a presença de polissacarídeos/açucares nas amostras de ninho. Pretende-se que a partir dos resultados da caracterização do material constituinte dos ninhos se possam retirar sugestões para o desenvolvimento de soluções de estabilização e de melhoramento de elementos construtivos existentes de terra crua.

Made available in DSpace on 2022-04-29T08:44:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-01-01 Background: Oral squamous cell carcinoma (OSCC) is a frequent neoplasm, which is usually aggressive and has unpredictable biological behavior and unfavorable prognosis. The comprehension of the molecular basis of this variability should lead to the development of targeted therapies as well as to improvements in specificity and sensitivity of diagnosis. Results: Samples of primary OSCCs and their corresponding surgical margins were obtained from male patients during surgery and their gene expression profiles were screened using whole-genome microarray technology. Hierarchical clustering and Principal Components Analysis were used for data visualization and One-way Analysis of Variance was used to identify differentially expressed genes. Samples clustered mostly according to disease subsite, suggesting molecular heterogeneity within tumor stages. In order to corroborate our results, two publicly available datasets of microarray experiments were assessed. We found significant molecular differences between OSCC anatomic subsites concerning groups of genes presently or potentially important for drug development, including mRNA processing, cytoskeleton organization and biogenesis, metabolic process, cell cycle and apoptosis. Conclusion: Our results corroborate literature data on molecular heterogeneity of OSCCs. Differences between disease subsites and among samples belonging to the same TNM class highlight the importance of gene expression-based classification and challenge the development of targeted therapies. Centro de Pesquisa Experimental Instituto Israelita de Ensino e Pesquisa Albert Einstein Laboratório de Biologia Molecular Hospital Heliópolis Departamento de Cirurgia de Cabeça e Pescoço Hospital das Clínicas Faculdade de Medicina Universidade de São Paulo Departamento de Neurologia e Neurocirurgia Universidade Federal de São Paulo Departamento de Estomatologia Faculdade de Odontologia Universidade de São Paulo Departamento de Pediatria Faculdade de Medicina Universidade de São Paulo Departamento de Biologia Molecular Faculdade de Medicina de São José do Rio Preto Departamento de Genética e Biologia Evolutiva Instituto de Biociências Universidade de São Paulo Departamento de Patologia Faculdade de Medicina Hospital Heliópolis Departamento e Instituto de Psiquiatria Faculdade de Medicina USP Serviço de Cirurgia de Cabeça e Pescoço Faculdade de Medicina de Ribeirão Preto USP Serviço de Cirurgia de Cabeça e Pescoço Instituto do Câncer Arnaldo Vieira de Carvalho Departamento de Análises Clínicas Toxicológicas e Bromatológicas Faculdade de Ciências Farmacêuticas de Ribeirão Preto USP Departamento de Cirurgia de Cabeça e Pescoço Faculdade de Medicina USP Departamento de Pediatria Faculdade de Medicina USP Departamento de Biociências e Diagnóstico Bucal Faculdade de Odontologia UNESP Departamento de Estomatologia Faculdade de Odontologia USP Departamento de Neurologia e Neurocirurgia UNIFESP Departamento de Patologia Faculdade de Medicina de Ribeirão Preto USP Instituto de Ensino e Pesquisa Albert Einstein Departamento de Genética Faculdade de Medicina de Ribeirão Preto USP Ciências da Computação UNIVAP Departamento de Biologia Molecular Faculdade de Medicina Departamento de Epidemiologia Faculdade de Saúde Pública USP Departamento de Clínica Médica Faculdade de Medicina de Ribeirão Preto USP Departamento de Biociências e Diagnóstico Bucal Faculdade de Odontologia UNESP