Chemical abundances and kinematics of barium stars

In this paper we present an homogeneous analysis of photospheric abundances based on high-resolution spectroscopy of a sample of 182 barium stars and candidates. We determined atmospheric parameters, spectroscopic distances, stellar masses, ages, luminosities and scale height, radial velocities, abundances of the Na, Al, $alpha$-elements, iron-peak elements, and s-process elements Y, Zr, La, Ce, and Nd. We employed the local-thermodynamic-equilibrium model atmospheres of Kurucz and the spectral analysis code {\sc moog}. We found that the metallicities, the temperatures and the surface gravities for barium stars can not be represented by a single gaussian distribution. The abundances of $alpha$-elements and iron peak elements are similar to those of field giants with the same metallicity. Sodium presents some degree of enrichment in more evolved stars that could be attributed to the NeNa cycle. As expected, the barium stars show overabundance of the elements created by the s-process. By measuring the mean heavy-element abundance pattern as given by the ratio [s/Fe], we found that the barium stars present several degrees of enrichment. We also obtained the [hs/ls] ratio by measuring the photospheric abundances of the Ba-peak and the Zr-peak elements. Our results indicated that the [s/Fe] and the [hs/ls] ratios are strongly anti-correlated with the metallicity. Our kinematical analysis showed that 90% of the barium stars belong to the thin disk population. Based on their luminosities, none of the barium stars are luminous enough to be an AGB star, nor to become self-enriched in the s-process elements. Finally, we determined that the barium stars also follow an age-metallicity relation.Comment: 30 pages, 26 figures, 18 tables, accepted for publication in MNRA

Novel optical PVC probes for on-site detection/determination of fluoroquinolones in a solid/liquid interface: Application to the determination of Norfloxacin in aquaculture water

A novel optical disposable probe for screening fluoroquinolones in fish farming waters is presented, having Norfloxacin (NFX) as target compound. The colorimetric reaction takes place in the solid/liquid interface consisting of a plasticized PVC layer carrying the colorimetric reagent and the sample solution. NFX solutions dropped on top of this solid-sensory surface provided a colour change from light yellow to dark orange. Several metals were tested as colorimetric reagents and Fe(III) was selected. The main parameters affecting the obtained colour were assessed and optimised in both liquid and solid phases. The corresponding studies were conducted by visible spectrophotometry and digital image acquisition. The three coordinates of the HSL model system of the collected image (Hue, Saturation and Lightness) were obtained by simple image management (enabled in any computer). The analytical response of the optimised solid-state optical probe against concentration was tested for several mathematical transformations of the colour coordinates. Linear behaviour was observed for logarithm NFX concentration against Hue+Lightness. Under this condition, the sensor exhibited a limit of detection below 50 μM (corresponding to about 16 mg/mL). Visual inspection also enabled semi-quantitative information. The selectivity was ensured against drugs from other chemical groups than fluoroquinolones. Finally, similar procedure was used to prepare an array of sensors for NFX, consisting on different metal species. Cu(II), Mn(II) and aluminon were selected for this purpose. The sensor array was used to detect NFX in aquaculture water, without any prior sample manipulation

Spatio-temporal distribution and target species of longline fish eries off Southeastern/Southern Brazil between 2000 and 2011

In the presente study, cluster analysis was performed to classify 1080 interviews with captains of national pelagic longline fleet (2000 to 2011), and 38 trips of the chartered fleet (2003 to 2008), in relation to the composition of species landed. For the national fleet 4 groups were identified: 1 - Albacores, 2 - Blue shark, 3 - Swordfish, and 4 - Dolphinfish. For the chartered fleet 3 groups were identified: 1 - Swordfish, 2 - Blue shark, and 3 - Albacores. The results indicated that part of the national fleet change their strategies according to the availability of the target species and market demand (internal and external). A part of the fleet from Espírito Santo state operates in the region between December and March, exclusively to capture dolphinfish. The chartered fleet differed from the national one as regards the fishing areas of each target species, mainly as regards swordfish and blue shark. Despite the great difference in the data sets, it is evident that both the national and the chartered fleets operated in accordance with their peculiarities and technological development, adopting strategies that optimize catches and net profits per trip.No presente estudo, uma análise de agrupamento foi realizada para classificar 1080 entrevistas com mestres da frota nacional de espinhel pelágico (2000 à 2011), e 38 embarques da frota estrangeira arrendada (2003 a 2008), em relação à composição das espécies desembarcadas. Para a frota nacional, foram identificados 4 grupos: 1 - Albacoras; 2 - Tubarãoazul; 3 - Meca; e 4 - Dourado. Para a frota estrangeira arrendada foram identificados 3 grupos: 1 - Meca; 2 - Tubarão-azul; e 3 - Albacoras. Os resultados indicam que parte da frota nacional altera suas estratégias de pesca de acordo com a disponibilidade da espéciealvo e pela demanda do mercado (interno e externo). Uma parcela da frota oriunda do Espírito Santo opera na região durante alguns meses de verão (dezembro a março), exclusivamente na captura do dourado. Para a frota estrangeira arrendada, ocorrem diferenças principalmente nas áreas de pesca para cada uma das espécies, sendo a frota direcionada principalmente para a captura da meca e tubarão-azul. Apesar da grande diferença no conjunto de dados, fica evidente que a frota nacional e estrangeira operam de acordo com suas particularidades e desenvolvimento tecnológico, adotando estratégias que otimizem as capturas e os lucros líquidos por viagem

Monitoring the ex-vivo expansion of human mesenchymal stem/stromal cells in xeno-free microcarrier-based reactor systems by MIR spectroscopy

Human mesenchymal stem/stromal cells (MSCs) have received considerable attention in the field of cell-based therapies due to their high differentiation potential and ability to modulate immune responses. However, since these cells can only be isolated in very low quantities, successful realization of these therapies requires MSCs ex-vivo expansion to achieve relevant cell doses. The metabolic activity is one of the parameters often monitored during MSCs cultivation by using expensive multi-analytical methods, some of them time-consuming. The present work evaluates the use of mid-infrared (MIR) spectroscopy, through rapid and economic high-throughput analyses associated to multivariate data analysis, to monitor three different MSCs cultivation runs conducted in spinner flasks, under xeno-free culture conditions, which differ in the type of microcarriers used and the culture feeding strategy applied. After evaluating diverse spectral preprocessing techniques, the optimized partial least square (PLS) regression models based on the MIR spectra to estimate the glucose, lactate and ammonia concentrations yielded high coefficients of determination (R2 ≥ 0.98, ≥0.98, and ≥0.94, respectively) and low prediction errors (RMSECV ≤ 4.7%, ≤4.4% and ≤5.7%, respectively). Besides PLS models valid for specific expansion protocols, a robust model simultaneously valid for the three processes was also built for predicting glucose, lactate and ammonia, yielding a R2 of 0.95, 0.97 and 0.86, and a RMSECV of 0.33, 0.57, and 0.09 mM, respectively. Therefore, MIR spectroscopy combined with multivariate data analysis represents a promising tool for both optimization and control of MSCs expansion processes

Host-Tailored Sensors for Leucomalachite Green Potentiometric Measurements

A new biomimetic sensor for leucomalachite green host-guest interactions and potentiometric transduction is presented. The artificial host was imprinted in methacrylic acid or acrylamido-2-methyl-1-propanesulfonic acid-based polymers. Molecularly imprinted particles were dispersed in 2-nitrophenyloctyl ether and trapped in poly(vinyl chloride). The potentiometric sensors exhibited a near-Nernstian response in steady state evaluations, with slopes and detection limits ranging from 45.8 to 81.2 mV and 0.28 to 1.01 , respectively. They were independent from the pH of test solutions within 3 to 5. Good selectivity was observed towards drugs that may contaminate water near fish cultures, such as oxycycline, doxycycline, enrofloxacin, trimethoprim, creatinine, chloramphenicol, and dopamine. The sensors were successfully applied to field monitoring of leucomalachite green in river samples. The method offered the advantages of simplicity, accuracy, applicability to colored and turbid samples, and automation feasibility

Incremento em diâmetro do mogno africano (Khaya ivorensis A. Chev.) no sistema silvipastoril em Terra Alta-PA.

A espécie Khaya ivorensis está gradativamente ocupando mais espaço dentre as madeiras nobres na prioridade dos investidores do setor florestal no Brasil. Em função de seu bom desenvolvimento a espécie vem sendo uma alternativa viável para plantio em sistemas de consorciados. Diante disto, o objetivo deste trabalho foi analisar o efeito do sistema de integração Lavoura-Pecuária-Floresta sobre o incremento em diâmetro do mogno africano (Khaya ivorensis) no município de Terra Alta - PA. O estudo foi composto por um tratamento de sistema de integração Lavoura-Pecuária-Floresta (iLPF), com cultivo de culturas anuais em consórcio com forrageiras e intercaladas com a espécie de mogno africano, e o sistema de controle, sendo neste caso o monocultivo (MF). As mensurações dos plantios foram realizadas anualmente no segundo e no oitavo ano. Em cada indivíduo foi mensurado o diâmetro à altura do peito (DAP) e a partir dessas variáveis foi calculado o Incremento Médio Anual em diâmetro (IMADAP). Os resultados estatísticos demonstraram crescimento em DAP do mogno africano expressou diferença significativa entre os tratamentos a que foi exposto, em todas as idades. O IMADAP nos anos de análise expressou maiores valores no sistema iLPF comparado ao sistema de controle (MF). Como integrante florestal do sistema de integração Lavoura-Pecuária-Floresta revela-se propícia para recuperação de áreas degradadas em conformidade do bom crescimento em DAP e taxas de IMADAP, expressando-se como adequação à área do experimento, sendo apropriado ao uso deste sistema