Immobilization of spray dried E. coli containing recombinant aminotransferase using hydrous titanium oxide

Dissertação mest., Engenharia Biológica, Universidade do Algarve, 2009Chiral amines are important building blocks for the pharmaceutical and agrochemical industry. They have many applications and are therefore of economical importance. Their production has mostly been achieved by enzymatic resolution. Aminotransferase, the enzyme most commonly used is known to be a pyridoxal-5- phosphate (PLP) dependent enzyme and it is commercialized in a spray dried Escherichia coli formulation. Since there is a great market for this enzyme and all the products it can synthesize, it is essential to constantly improve its efficiency and make it even more economically attractive. Several studies have been conducted to achieve this purpose, one of these being the reutilization of the biocatalyst by immobilization. In this work, immobilization of the biocatalyst was performed using a different approach than what has been tried before. The approach is based on interaction between hydrous transition metal oxides, mainly the hydrous titanium oxide (TiOx), and biological entities such as cells, enzymes and similar. Hydrous titanium oxide has the ability to bind the cells and enzymes via hydroxyl groups forming partial covalent bonds. Using this method, the biocatalyst was successfully immobilized and its reutilization was demonstrated for several batches. Studies on enzyme kinetics, storage stability, temperature effect, and loading capacity were performed to validate the usefulness of the immobilization method for the potential use in a large scale process

TÓPICOS DE NANOCIÊNCIA PARA O ENSINO DE CONCEITOS MATEMÁTICOS NOS NONOS ANOS

O presente trabalho pretende explorar a matemática envolvida na Nanociência, principalmente noestudo das propriedades dos nanomateriais. O trabalho faz parte das atividades do curso deespecialização em pesquisa e prática pedagógica do IFSC campus Gaspar. Surgiu de uma ideia doorientador e está sendo desenvolvida pelo discente que é professor de matemática. Justifica-se pelanecessidade apontada em diversos textos legais e por diversos pesquisadores em desenvolver umensino que abarque diversas disciplinas e a promoção de uma alfabetização científica e tecnológica.A Nanociência por si só é apontada como uma área interdisciplinar e por ser uma área científicacontempla as duas necessidades apontadas. Estudos envolvendo Nanociência na educação o fazemem nível médio, entretanto acredita-se que com as adaptações necessárias o tema pode ser abordadojá no ensino fundamental. Os objetivos deste trabalho são o de promover um ensino de matemáticamais significativo e conectado com a realidade do mundo ao mesmo tempo em que fomenta aalfabetização científica e tecnológica. Será desenvolvida e aplicada uma sequência didática visandoexplicar as propriedades dos nanomaterias no que diz respeito a sua relação área de superfície evolume. Durante a aplicação desta sequência espera-se que novas dúvidas apareçam e que estasgerem uma continuidade dos trabalhos. A pesquisa será aplicada em uma escola da rede públicamunicipal com duas turmas de nono ano do ensino fundamental. Os dados serão coletados atravésde questionários semiestruturados antes e depois da aplicação da sequência didática. Até o momentonão há conclusões a respeito da efetividade do trabalho visto que ainda está em fase inicial deaplicação, mas a pesquisa bibliográfica desenvolvida mostra o tema como bastante promissor

Discovery of a cluster of galaxies behind the Milky Way: X-ray and optical observations

We report the discovery of Cl 2334+48, a rich cluster of galaxies in the Zone of Avoidance, identified in public images from the XMM-Newton archive. We present the main properties of this cluster using the XMM-Newton X-ray data, along with new optical spectroscopic and photometric observations. Cl 2334+48 is located at z = 0.271 +/- 0.001, as derived from the optical spectrum of the brightest member galaxy. Such redshift agrees with a determination from the X-ray spectrum (z = 0.263 (+0.012/-0.010)), in which an intense emission line is matched to the rest wavelength of the Fe Kalpha complex. Its intracluster medium has a plasma temperature of 4.92 (+0.50/-0.48) keV, sub-solar abundance (0.38 +/- 0.12 Zsun), and a bolometric luminosity of 3.2 x 10^44 erg/s. A density contrast delta = 2500 is obtained in a radius of 0.5 Mpc/h70, and the corresponding enclosed mass is 1.5 x 10^14 Msun. Optical images show an enhancement of g'-i' > 2.5 galaxies around the central galaxy, as expected if these were cluster members. The central object is a luminous E-type galaxy, which is displaced ~ 40 kpc/h70 from the cluster X-ray center. In addition, it has a neighbouring arc-like feature (~ 22" or 90 kpc/h70 from it), probably due to strong gravitational lensing. The discovery of Cl 2334+48 emphasises the remarkable capability of the XMM-Newton to reveal new clusters of galaxies in the Zone of Avoidance.Comment: 9 pages, 11 figures, Accepted for publication in A&A (on July 12, 2006

Avaliação das diferenças de gênero nas estratégias de enfrentamento da dor lombar

El dolor lumbar puede ser visto como un gran problema de salud pública. Las diferencias de género son importantes factores que influyen en los síntomas y en las respuestas del comportamiento. El objetivo de este estudio fue investigar las diferencias de género en los comportamientos de dolor y en el manejo del dolor lumbar crónico. La muestra estuvo conformada por 158 participantes (66,5% mujeres), con edades entre los 30 y 88 años que fueron diagnosticados con artrosis lumbar. Los instrumentos utilizados fueron: la Escala Visual Analógica, el Cuestionario de Calidad de Vida y un cuestionario para evaluar las actividades de ocio y distracción del dolor. Los resultados del MANOVA demostraron que las mujeres presentaron mayor percepción del dolor que los hombres. También fue posible observar frecuencias más altas de actividades sociales en las mujeres, así como correlaciones significativas entre las actividades sociales y los dominios psicológicos, sociales y medio ambientales. En conclusión, las mujeres presentan un mayor número de estrategias de afrontamiento para el dolor, lo cual puede influir positivamente en su calidad de vida.A dor lombar pode ser vista como um grande problema de saúde pública. As diferenças de gênero são importantes fatores que influenciam nos sintomas e nas respostas do comportamento. O objetivo deste estudo foi pesquisar as diferenças de gênero nos comportamentos de dor e na gestão da dor lombar crônica. A amostra foi conformada por 158 participantes (66,5% mulheres), com idade entre 30 e 88 anos, que foram diagnosticadas com artrose lombar. Os instrumentos utilizados foram: a Escala Visual Analógica, o Questionário de Qualidade de Vida e um questionário para avaliar as atividades de lazer e distração da dor. Os resultados do MANOVA demonstraram que as mulheres apresentaram maior percepção da dor do que os homens. Também foi possível observar frequências mais altas de atividades sociais nas mulheres, bem como correlações significativas entre as atividades sociais e os domínios psicológicos, sociais e meio ambientais. Em conclusão, as mulheres apresentaram um maior número de estratégias de enfrentamento para a dor, o que pode influenciar positivamente em sua qualidade de vida.Low-back pain is considered a serious public health problem. Gender differences are important factors that influence symptoms and behavioral responses. This research aimed to investigate gender differences in pain behaviors and pain management of chronic low back pain. The sample consisted of 158 participants (66.5% female), aged 30-88 who were diagnosed with Lumbar Osteoarthritis. The instruments used were the Visual Analogue Scale, the Quality of Life Questionnaire and a questionnaire to assess leisure and distraction activities from pain. Results of MANOVA showed that women have significant greater pain perception than men. Higher frequencies of social activities were also observed for women as well as significant correlations between social activities and psychological, social and environmental domains. In conclusion, women presented a greater number of coping strategies for pain than men, which probably tend to have a positive influence in their life quality

Stellar jitter from variable gravitational redshift: implications for RV confirmation of habitable exoplanets

A variation of gravitational redshift, arising from stellar radius fluctuations, will introduce astrophysical noise into radial velocity measurements by shifting the centroid of the observed spectral lines. Shifting the centroid does not necessarily introduce line asymmetries. This is fundamentally different from other types of stellar jitter so far identified, which do result from line asymmetries. Furthermore, only a very small change in stellar radius, ~0.01%, is necessary to generate a gravitational redshift variation large enough to mask or mimic an Earth-twin. We explore possible mechanisms for stellar radius fluctuations in low-mass stars. Convective inhibition due to varying magnetic field strengths and the Wilson depression of starspots are both found to induce substantial gravitational redshift variations. Finally, we investigate a possible method for monitoring/correcting this newly identified potential source of jitter and comment on its impact for future exoplanet searches.Comment: 6 pages, 1 figure, 1 tabl

Effective Field Theory for Layered Quantum Antiferromagnets with Non-Magnetic Impurities

We propose an effective two-dimensional quantum non-linear sigma model combined with classical percolation theory to study the magnetic properties of site diluted layered quantum antiferromagnets like La$_{2}$Cu$_{1-x}$M$_x$O$_{4}$ (M$=$Zn, Mg). We calculate the staggered magnetization at zero temperature, $M_s(x)$, the magnetic correlation length, $\xi(x,T)$, the NMR relaxation rate, $1/T_1(x,T)$, and the N\'eel temperature, $T_N(x)$, in the renormalized classical regime. Due to quantum fluctuations we find a quantum critical point (QCP) at $x_c \approx 0.305$ at lower doping than the two-dimensional percolation threshold $x_p \approx 0.41$. We compare our results with the available experimental data.Comment: Final version accepted for publication as a Rapid Communication on Physical Review B. A new discussion on the effect of disorder in layered quantum antiferromagnets is include

Initial psychological responses to influenza A, H1N1 ("Swine flu")

Background The outbreak of the pandemic flu, Influenza A H1N1 (Swine Flu) in early 2009, provided a major challenge to health services around the world. Previous pandemics have led to stockpiling of goods, the victimisation of particular population groups, and the cancellation of travel and the boycotting of particular foods (e.g. pork). We examined initial behavioural and attitudinal responses towards Influenza A, H1N1 ("Swine flu") in the six days following the WHO pandemic alert level 5, and regional differences in these responses. Methods 328 respondents completed a cross-sectional Internet or paper-based questionnaire study in Malaysia (N = 180) or Europe (N = 148). Measures assessed changes in transport usage, purchase of preparatory goods for a pandemic, perceived risk groups, indicators of anxiety, assessed estimated mortality rates for seasonal flu, effectiveness of seasonal flu vaccination, and changes in pork consumption Results 26% of the respondents were 'very concerned' about being a flu victim (42% Malaysians, 5% Europeans, p < .001). 36% reported reduced public transport use (48% Malaysia, 22% Europe, p < .001), 39% flight cancellations (56% Malaysia, 17% Europe, p < .001). 8% had purchased preparatory materials (e.g. face masks: 8% Malaysia, 7% Europe), 41% Malaysia (15% Europe) intended to do so (p < .001). 63% of Europeans, 19% of Malaysians had discussed the pandemic with friends (p < .001). Groups seen as at 'high risk' of infection included the immune compromised (mentioned by 87% respondents), pig farmers (70%), elderly (57%), prostitutes/highly sexually active (53%), and the homeless (53%). In data collected only in Europe, 64% greatly underestimated the mortality rates of seasonal flu, 26% believed seasonal flu vaccination gave protection against swine flu. 7% had reduced/stopped eating pork. 3% had purchased anti-viral drugs for use at home, while 32% intended to do so if the pandemic worsened. Conclusion Initial responses to Influenza A show large regional differences in anxiety, with Malaysians more anxious and more likely to reduce travel and to buy masks and food. Discussions with family and friends may reinforce existing anxiety levels. Particular groups (homosexuals, prostitutes, the homeless) are perceived as at greater risk, potentially leading to increased prejudice during a pandemic. Europeans underestimated mortality of seasonal flu, and require more information about the protection given by seasonal flu inoculation

Clar's Theory, STM Images, and Geometry of Graphene Nanoribbons

We show that Clar's theory of the aromatic sextet is a simple and powerful tool to predict the stability, the \pi-electron distribution, the geometry, the electronic/magnetic structure of graphene nanoribbons with different hydrogen edge terminations. We use density functional theory to obtain the equilibrium atomic positions, simulated scanning tunneling microscopy (STM) images, edge energies, band gaps, and edge-induced strains of graphene ribbons that we analyze in terms of Clar formulas. Based on their Clar representation, we propose a classification scheme for graphene ribbons that groups configurations with similar bond length alternations, STM patterns, and Raman spectra. Our simulations show how STM images and Raman spectra can be used to identify the type of edge termination