Evaluation of laser induced breakdown spectroscopy for the determination of macronutrients in plant materials

Laser induced breakdown spectroscopy (LIBS) has become an analytical tool for the direct analysis of a large variety of materials in order to provide qualitative and/or quantitative information. However, there is a lack of information for LIBS analysis of agricultural and environmental samples. In this work a LIBS system has been evaluated for the determination of macronutrients (P, K, Ca, Mg) in pellets of vegetal reference materials. An experimental setup was designed by using a Nd:YAG laser operating at 1064 nm and an Echelle spectrometer with ICCD detector. The plasma temperature was estimated by Boltzmann plots and instrumental paragmeters such as delay time, lens-to-sample distance and pulse energy were evaluated. Certified reference materials as well as reference materials were used for analytical calibrations of P, K, Ca, and Mg. Most results of the direct analysis of plant samples by LIBS were in reasonable agreement with those obtained by ICP OES after wet acid decomposition. (C) 2008 Elsevier B.V. All rights reserved.

Chronostratigraphy and radiocarbon age inversion in the Holocene regressive barrier of Parana, southern Brazil

Twenty-two (14)C datings were performed at the central sector of the Parana coast to define Holocene regressive barrier evolution. The barrier Pleistocene substratum was ascribed an age between 40400 and 30000 yr BP, but it can also represent the penultimate sea level highstand during marine isotope stage 5e. The Holocene barrier samples provided ages between 8542-8279 and 2987-2751 cal yr BP, and showed at least six age inversions that were related to age differences between in situ or low-distance transported shells or trunk fragments, and high-distance transported vegetal debris, wood fragments and organic matter samples. The regressive Holocene barrier age was 4402-4135 cal yr BP near the base, and 2987-2751 cal yr BP near the top. Most of the vegetal remains were transported by ebb tidal currents from the estuaries to the inner shelf below wave base level during the mid-Holocene highstand; they were transported onshore by storm waves and littoral currents during the sea level lowering after the sea level maximum, and were deposited mainly as middle shoreface swaley cross-stratification facies. (C) 2008 Published by Elsevier B.V.

Optimization and validation of a LIBS method for the determination of macro and micronutrients in sugar cane leaves

Laser induced breakdown spectrometry (LIBS) was applied for the determination of macro (P, K, Ca, Mg) and micronutrients (B, Cu, Fe, Mn and Zn) in sugar cane leaves, which is one of the most economically important crops in Brazil. Operational conditions were previously optimized by a neuro-genetic approach, by using a laser Nd:YAG at 1064 nm with 110 mJ per pulse focused on a pellet surface prepared with ground plant samples. Emission intensities were measured after 2.0 mu s delay time, with 4.5 mu s integration time gate and 25 accumulated laser pulses. Measurements of LIBS spectra were based on triplicate and each replicate consisted of an average of ten spectra collected in different sites (craters) of the pellet. Quantitative determinations were carried out by using univariate calibration and chemometric methods, such as PLSR and iPLS. The calibration models were obtained by using 26 laboratory samples and the validation was carried out by using 15 test samples. For comparative purpose, these samples were also microwave-assisted digested and further analyzed by ICP OES. In general, most results obtained by LIBS did not differ significantly from ICP OES data by applying a t-test at 95% confidence level. Both LIBS multivariate and univariate calibration methods produced similar results, except for Fe where better results were achieved by the multivariate approach. Repeatability precision varied from 0.7 to 15% and 1.3 to 20% from measurements obtained by multivariate and univariate calibration, respectively. It is demonstrated that LIBS is a powerful tool for analysis of pellets of plant materials for determination of macro and micronutrients by choosing calibration and validation samples with similar matrix composition.

Frozen Chicken for Wild Fish: Nutritional Transition in the Brazilian Amazon Region Determined by Carbon and Nitrogen Stable Isotope Ratios in Fingernails

Objectives: Amazonian populations are experiencing dietary changes characteristic of the nutrition transition. However, the degree of change appears to vary between urban and rural settings. To investigate this process, we determined carbon and nitrogen stable isotope ratios in fingernails and dietary intake of Amazonian populations living along a rural to urban continuum along the Solimoes River in Brazil. Methods: Carbon and nitrogen stable isotope ratios were analyzed from the fingernails of 431 volunteer subjects living in different settings ranging from rural villages, small towns to urban centers along the Solimoes River. Data from 200 dietary intake surveys were also collected using food frequency questionnaires and 24-h recall interviews in an effort to determine qualitative aspects of diet composition. Results: Fingernail delta(13)C values (mean standard deviation) were -23.2 +/- 1.3, 20.2 +/- 1.5, and 17.4 +/- 1.3 parts per thousand and delta(15)N values were 11.8 +/- 0.6, 10.4 +/- 0.8, and 10.8 +/- 0.7 parts per thousand for those living in rural villages, small towns, and major cities, respectively. We found a gradual increase in the number of food items derived from C(4) plant types (meat and sugar) and the replacement of food items derived from C(3) plant types (fish and manioc flour) with increasing size of urban centers. Conclusion: Increasing urbanization in the Brazilian Amazon is associated with a significant change in food habits with processed and industrialized products playing an increasingly important role in the diet and contributing to the nutrition transition in the region. Am. J. Hum. Biol. 23:642-650, 2011. (C) 2011 Wiley-Liss, Inc.

Agronomic evaluation of calcined crandallite from three Brazilian phosphate deposits

Samples from the weathering mantle containing crandallite of three Brazilian phosphate deposits, Tapira, Catalo, and Juqui, were characterized, calcined, and agronomically evaluated. The calcination process increased total phosphorus (P) and neutral ammonium citrate soluble (NAC) P contents of all samples. The NAC solubility of original Tapira, Catalo, and Juqui was about 5% of total P, whereas for calcined samples it was 54, 16, and 53%, respectively. In a greenhouse study, rates of P were applied at 0, 10, 20, 40, 80, and 120mg P kg(-1) from the calcined materials and MCP (monocalcium phosphate) to an Ultisol cropped with upland and flooded rice for 65 days. The results showed that the calcined P samples increased dry-matter yield and P uptake with increasing rates of P applied for both crops. Tapira and Juqui were more effective for flooded than for upland rice. The calculated values of relative agronomic effectiveness of Tapira, Catalo, and Juqui with respect to MCP were 57, 48, and 53% in dry-matter yield for upland rice and 64, 50, and 69% for flooded rice, respectively.

Deep weathering and landscape evolution in a tropical plateau

The thick weathering profiles of humid tropical areas are an important, yet generally neglected, source of information on landscape evolution. Six complete profiles of the weathering mantle were sampled by drilling on the three stepped levels of the Campos do Jordao Plateau, on the NW flank of the Continental Rift of Southeastern Brazil. Mineralogical and micromorphological analyses of drill core samples, complemented by geochemical interpretations and by previous data on the upper saprolite, indicate continuity of a general lateritic trend during the entire process of mantle formation. Lateritization phases of different intensity were defined and considered to reflect adjustment to changes in environmental conditions created by the gradual uplift of the plateau to its present position. Older and more superficial materials related to intense lateritic weathering are characterized by allitization with direct formation of gibbsite from silicates, probably related to tropical climates existing immediately before the formation of the continental rift, during the Paleogene, and also before any significant increase in altitude. Monosialitization phase with general kaolinitization and restricted indirect formation of gibbsite from silicates could be associated to less aggressive climates that followed the Neogene (Miocene?) accentuation of uplift rates along the continental rift. The changes produced by uplift in the tropical climate eventually favored the development of a podzolization trend in soils above 1800m. (C) 2011 Elsevier BM. All rights reserved.

The use of contingent valuation for evaluating protected areas in the developing world: Economic valuation of Morro do Diabo State Park, Atlantic Rainforest, Sao Paulo State (Brazil)

The Brazilian Atlantic Rainforest is internationally recognised as one of the most biodiverse and threatened tropical forests in the world [Myers, N., Mittermeier, R.A., Mittermeier, C.G., da Fonseca, G.A.B., Kent, J., 2000. Biodiversity hotspots for conservation priorities. Nature 403, 853-858]. The Seasonal Semi-Deciduous Forest is among the most fragmented and threatened biomes of the Atlantic Rainforest Domain. The largest remnant of this biome (35,000 ha) is protected by the Morro do Diabo State Park (MDSP), situated in the area known as the Pontal do Paranapanema, in Sao Paulo State, Brazil. Despite its environmental importance, the park is under political, economic and demographic pressure. The main aim of our research was to estimate the population`s willingness to pay (WTP) for the conservation of MDSP and for the Atlantic Rainforest`s remnants in Sao Paulo State as a whole, by means of the contingent valuation method (CVM). The results featured a high incidence of null WTP and of protest votes. Nevertheless, the population is willing to pay US$ 2,113,548.00/year (R$ 7,080,385.00/year) for the conservation of the MDSP (use and existence values), or US$ 60.39 ha/year (R$ 202.30/ha/year). The results indicate that the preservation value is strongly associated to the population`s ability to pay, increasing with income levels. Qualitative research questions showed that the population considers protected areas to be very important. Still, the valuation of MDSP revealed a gap between the government budget allotted to the park and the value assigned to the area by the public. (C) 2007 Elsevier B.V. All rights reserved.

Nickel sorption capacity of ground xylem of Quercus ilex trees and effects of selected ligands present in the xylem sap

In this work the influence of four different ligands present in the xylem sap of Quercus ilex (histidine, citric, oxalic and aspartic acids) on Ni(II) adsorption by xylem was investigated. Grinded xylem was trapped in acrylic columns and solutions of Ni(II), in the absence and presence of the four ligands prepared in KNO(3) 0-1 mol L(-1) at pH 5.5, were percolated through the column. Aliquots of solutions were recovered in the column end for Ni determination by graphite furnace atomic absorption spectrometry (GFAAS). The experimental. data to describe Ni sorption by xylem in both the presence and absence of ligands was better explained by the Freundlich isotherm model. The decreasing affinity order of ligands for Ni was: oxalic acid > citric acid > histidine > aspartic acid. On the other hand, the Ni(II) adsorption by xylem increased following the inverse sequence of ligands. Potentiometric titrations of acidic groups were carried out to elucidate the sorption site groups available in Q. ilex xylem. The potentiometric titration has shown three sorption sites: pK(a) 2.6 (57.7% of the sorption sites), related to monobasic aliphatic carboxylic acids or nitrogen aromatic bases, pK(a) 8.1 (9.6%) and pK(a) 9.9 (32.7%), related to phenolic groups. (C) 2008 Elsevier GmbH. All rights reserved.

The notion of structure and the information records of the documentary systems

Assuming as a starting point the acknowledge that the principles and methods used to build and manage the documentary systems are disperse and lack systematization, this study hypothesizes that the notion of structure, when assuming mutual relationships among its elements, promotes more organical systems and assures better quality and consistency in the retrieval of information concerning users` matters. Accordingly, it aims to explore the fundamentals about the records of information and documentary systems, starting from the notion of structure. In order to achieve that, it presents basic concepts and relative matters to documentary systems and information records. Next to this, it lists the theoretical subsides over the notion of structure, studied by Benveniste, Ferrater Mora, Levi-Strauss, Lopes, Penalver Simo, Saussure, apart from Ducrot, Favero and Koch. Appropriations that have already been done by Paul Otlet, Garcia Gutierrez and Moreiro Gonzalez. In Documentation come as a further topic. It concludes that the adopted notion of structure to make explicit a hypothesis of real systematization achieves more organical systems, as well as it grants pedagogical reference to the documentary tasks.

Validity and reliability of the Portuguese version of the Epilepsy Medication Treatment Complexity Index for Brazil

We evaluated the reliability and validity of a Brazilian-Portuguese version of the Epilepsy Medication Treatment Complexity Index (EMTCI). Interrater reliability was evaluated with the intraclass correlation coefficient (ICC), and validity was evaluated by correlation of mean EMTCI scores with the following variables: number of antiepileptic drugs (AEDs), seizure control, patients` perception of seizure control, and adherence to the therapeutic regimen as measured with the Morisky scale. We studied patients with epilepsy followed in a tertiary university-based hospital outpatient clinic setting, aged 18 years or older, independent in daily living activities, and without cognitive impairment or active psychiatric disease. ICCs ranged from 0.721 to 0.999. Mean EMTCI scores were significantly correlated with the variables assessed. Higher EMTCI scores were associated with an increasing number of AEDs, uncontrolled seizures, patients` perception of lack of seizure control, and poorer adherence to the therapeutic regimen. The results indicate that the Brazilian-Portuguese EMTCI is reliable and valid to be applied clinically in the country. The Brazilian-Portuguese EMTCI version may be a useful tool in developing strategies to minimize treatment complexity, possibly improving seizure control and quality of life in people with epilepsy in our milieu. (C) 2011 Elsevier Inc. All rights reserved.

Gender Differences in Life Expectancy and Disability-Free Life Expectancy Among Older Adults in Sao Paulo, Brazil

Background: Research on life expectancy has demonstrated the negative impact of disability on the health of older adults and its differential effects on women as evidenced by their higher disabled life expectancy (DLE). The goal of the present study was to investigate gender differences in total life expectancy (TLE), disability-free life expectancy (DFLE), and DLE; examine gender differences on personal care assistance among older adults in Sao Paulo, Brazil; and discuss the implications for public policies. Methods: The sample was drawn from two waves (2000, 2006) of the dataset of Salud, Bienestar, y Envejecimiento, a large longitudinal study conducted in Sao Paulo (n = 2,143). The study assessed disability using the activities of daily living (ADL). The interpolation of Markov Chain method was used to estimate gender differences in TLE, DLE, and DFLE. Findings: TLE at age 60 years was approximately 5 years longer for women than men. Women aged 60 years were expected to live 28% of their remaining lives twice the percentage for men with at least one ADL disability. These women also lived more years (M = 0.71, SE = 0.42) with three or more ADL disabilities than men (M = 0.82, SE = 0.16). In terms of personal care assistance, women received more years of assistance than men. Conclusion: Among older adults in Sao Paulo, women lived longer lives but experienced a higher and more severe disability burden than men. In addition, although women received more years of personal assistance than men, women experienced more unmet care assistance needs. Copyright (C) 2011 by the Jacobs Institute of Women`s Health. Published by Elsevier. Inc.

Risk factors for neonatal transfers from the Sapopemba free-standing birth centre to a hospital in Sao Paulo, Brazil

Objective: to identify risk factors associated with neonatal transfers from a free-standing birth centre to a hospital. Design: epidemiological case-control study. Setting: midwifery-led free-standing birth centre in Sao Paulo, Brazil. Participants: 96 newborns were selected from 2840 births between September 1998 and August 2005. Cases were defined as all new borns transferred from the birth centre to a hospital (n = 32), and controls were defined as new borns delivered at the same birth centre, during the same time period, and who had not been transferred to a hospital (n = 64). Measurements and findings: data were collected from medical records available at the birth centre. Univariate and multivariate analyses were performed using logistic regression. The multivariate analysis included outcomes with p<0.25, specifically: smoking during pregnancy, prenatal care appointments, labour complications, weight in relation to gestational age, and one-minute Apgar score. Of the foregoing outcomes, those that remained in the full regression model as a risk factor associated with neonatal transfer were: smoking during pregnancy [p = 0.009, odds ratio (OR) = 4.1,95% confidence interval (CI) 1.03-16.33], labour complications (p<0.001, OR = 5.5, 95% CI 1.06-28.26) and one-minute Apgar score <= 7 (p<0.001, OR = 7.8,95% CI 1.62-37.03). Key conclusions and implications for practice: smoking during pregnancy, labour complications and one-minute Apgar score <= 7 were confirmed as risk factors for neonatal transfer from the birth centre to a hospital. The identified risk factors can help to improve institutional protocols and formulate hypotheses for other studies. (C) 2009 Elsevier Ltd. All rights reserved.

The ethical component of professional competence in nursing: An analysis

The purpose of this article is to initiate a philosophical discussion about the ethical component of professional competence in nursing from the perspective of Brazilian nurses. Specifically, this article discusses professional competence in nursing practice in the Brazilian health context, based on two different conceptual frameworks. The first framework is derived from the idealistic and traditional approach while the second views professional competence through the lens of historical and dialectical materialism theory. The philosophical analyses show that the idealistic view of professional competence differs greatly from practice. Combining nursing professional competence with philosophical perspectives becomes a challenge when ideals are opposed by the reality and implications of everyday nursing practice.

The effect of Sao Paulo`s smoke-free legislation on carbon monoxide concentration in hospitality venues and their workers

Background Studies have shown that there is no safe level of secondhand smoke (SHS) exposure and there is a close link between SHS and the risk of coronary heart disease and stroke. Carbon monoxide (CO) is one of the most important components present in SHS. Objective To evaluate the impact of the smoking ban law in the city of Sao Paulo, Brazil, on the CO concentration in restaurants, bars, night clubs and similar venues and in their workers. Methods In the present study we measured CO concentration in 585 hospitality venues. CO concentration was measured in different environments (indoor, semi-open and open areas) from visited venues, as well as, in the exhaled air from approximately 627 workers of such venues. Measurements were performed twice, before and 12 weeks after the law implementation. In addition, the quality of the air in the city during the same period of our study was verified. Results The CO concentration pre-ban and pot-ban in hospitality venues was indoor area 4.57 (3.70) ppm vs 1.35 (1.66) ppm (p<0.0001); semi-open 3.79 (2.49) ppm vs 1.16 (1.14) ppm (p<0.0001); open area 3.31 (2.2) ppm vs 1.31 (1.39) ppm (p<0.0001); smoking employees 15.78 (9.76) ppm vs 11.50 (7.53) ppm (p<0.0001) and non-smoking employees 6.88 (5.32) ppm vs 3.50 (2.21) ppm (p<0.0001). The average CO concentration measured in the city was lower than 1 ppm during both pre-ban and post-ban periods. Conclusion Sao Paulos smoking-free legislation reduced significantly the CO concentration in hospitality venues and in their workers, whether they smoke or not.

Baroreflex Sensitivity Impairment Is Associated With Cardiac Diastolic Dysfunction in Rats

Background: Studies have shown that the autonomic dysfunction accompanied by impaired baroreflex sensitivity was associated with higher mortality. However, the influence of decreased baroreflex sensitivity on cardiac function, especially in diastolic function, is not well understood. This study evaluated the morpho-functional changes associated with baroreflex impairment induced by chronic sinoaortic denervation (SAD). Methods and Results: Animals were divided into sinoaortic denervation (SAD) and control (C) groups. Baroreflex sensitivity was evaluated by tachycardic and bradycardic responses, induced by vasoactive drugs. Cardiac function was studied by echocardiography and by left ventricle (LV) catheterization. LV collagen content and the expression of regulatory proteins involved in intracellular Ca(2+) homeostasis were quantified. Results showed higher LV mass in SAD versus C animals. Furthermore, an increase in deceleration time of E-wave in the SAD versus the C group (2.14 +/- 0.07 ms vs 1.78 +/- 0.03 ms) was observed. LV end-diastolic pressure was increased and the minimum dP/dt was decreased in the SAD versus the C group (12 +/- 1.5 mm Hg vs 5.3 +/- 0.2 mm Hg and 7,422 +/- 201 vs 4,999 +/- 345 mm Hg/s, respectively). SERCA/NCX ratio was lower in SAD than in control rats. The same was verified in SERCA/PLB ratio. Conclusions: The results suggest that baroreflex dysfunction is associated with cardiac diastolic dysfunction independently of the presence of other risk factors. (J Cardiac Fail 2011;17:519-525)