Microalgae of the genus Nannochloropsis: Chemical composition and functional implications for human nutrition

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The effect of X-ray dust-scattering on a bright burst from the magnetar 1E 1547.0-5408

A bright burst, followed by an X-ray tail lasting ~10 ks, was detected during an XMM-Newton observation of the magnetar 1E 1547.0-5408 carried out on 2009 February 3. The burst, also observed by SWIFT/BAT, had a spectrum well fit by the sum of two blackbodies with temperatures of ~4 keV and 10 keV and a fluence in the 0.3-150 keV energy range of ~1e-5 erg/cm2. The X-ray tail had a fluence of ~4e-8 erg/cm2. Thanks to the knowledge of the distances and relative optical depths of three dust clouds between us and 1E 1547.0-5408, we show that most of the X-rays in the tail can be explained by dust scattering of the burst emission, except for the first ~20-30 s. We point out that other X-ray tails observed after strong magnetar bursts may contain a non-negligible contribution due to dust scattering.Comment: 8 pages, 2 tables and 10 figures; accepted to publication in MNRA

dCATCH—A Numerical Package for d-Variate near G-Optimal Tchakaloff Regression via Fast NNLS

We provide a numerical package for the computation of a d-variate near G-optimal polynomial regression design of degree m on a finite design space X ⊂ R d , by few iterations of a basic multiplicative algorithm followed by Tchakaloff-like compression of the discrete measure keeping the reached G-efficiency, via an accelerated version of the Lawson-Hanson algorithm for Non-Negative Least Squares (NNLS) problems. This package can solve on a personal computer large-scale problems where c a r d ( X ) × dim ( P 2 m d ) is up to 10 8 – 10 9 , being dim ( P 2 m d ) = 2 m + d d = 2 m + d 2 m . Several numerical tests are presented on complex shapes in d = 3 and on hypercubes in d > 3

Alkaline Water and Longevity: A Murine Study

The biological effect of alkaline water consumption is object of controversy. The present paper presents a 3-year survival study on a population of 150 mice, and the data were analyzed with accelerated failure time (AFT) model. Starting from the second year of life, nonparametric survival plots suggest that mice watered with alkaline water showed a better survival than control mice. Interestingly, statistical analysis revealed that alkaline water provides higher longevity in terms of \u201cdeceleration aging factor\u201d as it increases the survival functions when compared with control group; namely, animals belonging to the population treated with alkaline water resulted in a longer lifespan. Histological examination of mice kidneys, intestine, heart, liver, and brain revealed that no significant differences emerged among the three groups indicating that no specific pathology resulted correlated with the consumption of alkaline water. These results provide an informative and quantitative summary of survival data as a function of watering with alkaline water of long-lived mouse models

Peroxidase activity and total phenol content in citrus cuttings treated with different copper sources

Abstract The proper citrus cutting choice is considered of basic importance for a healthy and productive citriculture. Substrates composed of organic materials are widely used for the production of citrus seedlings but this can lead to plant copper deficiency, mainly caused by substrate high chelating properties. Copper is an essential heavy metal and is involved in many different plant physiological processes. This experiment was carried out in order to evaluate the behavior of 'Rangpur lime' lemon rootstock ( Citrus limonia Osbeck) grafted with cv. 'Valencia' ( Citrus sinensis L. Osbeck), when treated with different copper formulations, as cupric oxychloride (50% Cu — Novartis Biociencias™), cuprous oxide (32.8% Cu — Yara Vita™), chelated copper (5% Cu — Stoller™) and copper sulphate (25% Cu — Microsal™) analyzing the activity of peroxidase (POD) and the total content of phenols. The different copper formulations did not show significant differences about plant height, diameter, leaf and root dry weight. The comparison among copper treatments shows that cuprous oxide promoted the antioxidant system (POD activity and phenolic content) while chelated copper was not effective

Polyamine, peroxidase activity and total protein content during storage of bird-of-paradise

The present study was aimed to the determination of the effect of storage on some biochemical characteristics (PAs content, POX activity and total protein content) of flower tissue of bird-of-paradise. Flowers were selected and labeled, avoiding any mechanical damage, and randomly distributed in recipients for two postharvest trials. In the first experiment, flowers were placed in recipients containing tap water and stored in a cold room, at 7.5 \ubaC and 90 % RH, for a period of 12 days. In experiment 2, flowers were stored in room temperature for a period of 6 days. For biochemical characteristics, samples (sepals, petals, stems and bracts) from experiment 1 were collected at 0, 4, 8 and 12 days, and at 0, 2, 4 and 6 days for experiment 2. Results showed that flower bracts, stored at 7.5 \ub0C, presented a lower content of PAs (Put and Spd), when compared to samples stored at room temperature. In both experiments, a high content of PAs (Spm) was observed in flower tissues in relation to Put and Spd. An increase of POX activity was observed in sepals stored in the cold, and was related to PAs degradation during senescence. No differences in total protein content were observed between the two treatments. The present study provides numeric results on changes in level of PAs, POX activity and total protein during postharvest of bird-of-paradise

Contamination of a high-cell-density continuous bioreactor

Continuous fermentations were carried out with a recombinant flocculent Saccharomyces cerevisiae strain in an airlift bioreactor. Once operating under steady state at a dilution rate of 0.45 h−1, the bioreactor was contaminated with Escherichia coli cells. The faster growing E. coli strain was washed out of the bioreactor and the recombinant, slower growing flocculating S. cerevisiae strain remained as the only species detected in the bioreactor. Flocculation, besides allowing for the realization of high-cell-density systems with corresponding unusual high productivity, may be used as a selective property for controlling some contamination problems associated with prolonged continuous operation.Fundação para a Ciência e Tecnologia -PRAXIS XXI/BD/11306/97

Effect of spermidine on ornamental bromeliad cultured in vitro

Plants of the ornamental bromeliad, Aechmea blanchetiana (Baker) L.B. Smith obtained from seeds germinated in vitro, were treated with spermidine (Spd) at various concentrations (0, 10, 50 and 250 μM) or in the presence of 1.07 mM α-naphthaleneacetic acid (NAA) + 22.20 mM 6-benzyladenine (BA) or 0 mM NAA + 0 mM 6-BA for shoot induction and 0, 1.07 and 5.37 mM of NAA for root induction. The number of shoots, fresh and dry weight of shoots on shoot induction and fresh and dry weight of shoots and roots on root induction, and activity of peroxidases were evaluated. Polyamine Spd was not effective on shooting induction, rooting, mass accumulation of fresh and dry weight and had no influence on the activity of the enzyme peroxidase, and had a deleterious effect on dry matter accumulation in the treatment for shooting induction. Spd improved the qualitative and quantitative responses of in vitro rhizogenesis of A. blanchetiana as compared to the free polyamine medium. Peroxidase activity was higher in leaves of plants subjected to shoot induction, with 6-BA+NAA. The exogenous spermidine did not have effect on peroxidase activity.Keywords: Bromeliad, micropropagation, peroxidase activity, polyamin

Catalytically active bovine serum amine oxidase bound to fluorescent and magnetically drivable nanoparticles

Novel superparamagnetic surface-active maghemite nanoparticles (SAMNs) characterized by a diameter of 10 ± 2 nm were modified with bovine serum amine oxidase, which used rhodamine B isothiocyanate (RITC) adduct as a fluorescent spacer-arm. A fluorescent and magnetically drivable adduct comprised of bovine serum copper-containing amine oxidase (SAMN–RITC–BSAO) that immobilized on the surface of specifically functionalized magnetic nanoparticles was developed. The multifunctional nanomaterial was characterized using transmission electron microscopy, infrared spectroscopy, mass spectrometry, and activity measurements. The results of this study demonstrated that bare magnetic nanoparticles form stable colloidal suspensions in aqueous solutions. The maximum binding capacity of bovine serum amine oxidase was approximately 6.4 mg g−1 nanoparticles. The immobilization procedure reduced the catalytic activity of the native enzyme to 30% ± 10% and the Michaelis constant was increased by a factor of 2. We suggest that the SAMN–RITC–BSAO complex, characterized by a specific activity of 0.81 IU g−1, could be used in the presence of polyamines to create a fluorescent magnetically drivable H2O2 and aldehydes-producing system. Selective tumor cell destruction is suggested as a potential future application of this system

Polyamines, Gelling Agents in Tissue Culture, Micropropagation of Medicinal Plants and Bioreactors

Currently, tissue cultures of species of agricultural importance have wide applicability in industrial production processes. Tissue culture is a name given to a set of techniques that allow the regeneration of cells, tissues and organs of plants, from segments of plant organs or tissues, using nutrient solutions in aseptic and controlled environment. This regeneration is based on the totipotency of plant cells. Totipotency is a capability indicating that plant cells, in different times, may express the potential to form a new multicellular individual. Tissue culture appears to be a good alternative to conventional propagation, requiring less physical space, with high multiplication rate, without incidence of pests and diseases during cultivation, and enabling higher control of the variables involved. Thus, in the in vitro environment, with the required stimuli and appropriate conditions, different cell types express different behaviors, possibly leading to cell multiplication and differentiation into a specific tissue, characterized by a form and a function, which may lead to the regeneration of a new individual