50 research outputs found

    Chitosan/mangiferin particles for Cr(VI) reduction and removal

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    AbstractIn this work, chitosan/mangiferin particles (CMP) were prepared by spray-drying technique and characterized by SEM, DLS, FTIR, HPLC–UV and adsorption studies to investigate a possible application as a preventive material in cases of human and animal contamination with Cr(VI). CMP presented sizes ranging from nano to micrometers. Chitosan and mangiferin (MA) presence in the powder was confirmed by FTIR and MA quantification (136μg/mg) was performed using a calibration curve prepared by HPLC–UV. Adsorption capacity of Cr(VI) onto CMP was compared with chitosan and investigated in a batch system by considering the effects of various parameters like contact time, initial concentration of adsorbent and pH. Cr(VI) removal is pH dependent and it was found to be maximum at pH 5.0. The results showed that CMP has a potential application as a preventive material in cases of human or animal contamination with Cr(VI)

    Developing methods to compare tablet formulations of atorvastatin

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    Atorvastatin (ATV) is an antilipemic drug of great interest to the pharmaceutical industry. ATV does not appear in the monographs of Brazilian pharmacopoeia, and analytical methodologies for its determination have been validated. The chromatographic conditions used included: RP-18 column-octadecylsilane (250 x 4.6 mm, 5 mm), detection at 238 nm, mobile phase containing 0.1% phosphoric acid and acetonitrile (35:65% v/v), flow at 1.5 mL min-1, oven temperature at 30ºC, and injection volume of 10 mL. ATV is classified as a class II product, according to the biopharmaceutical classification system. As such, a dissolution test was proposed to evaluate pharmaceutical formulations on the market today, under the following conditions: water as a dissolution medium, 1000 mL as a volume, paddle apparatus at a rotation speed of 50 rpm, 80% (Q) in 15 minutes with UV spectrophotometer readings at 238 nm. In the pattern condition proposed as the ideal dissolution test, which appropriately differentiates amongst formulations, the generic product was not considered pharmaceutically equivalent; however, in other less differential dissolution methods, which also fall within appropriate legal parameters, this product could come to be regarded as generic.Atorvastatina (ATV) é um fármaco antilipêmico de grande interesse para a indústria farmacêutica. ATV não apresenta monografia na Farmacopéia Brasileira e metodologias analíticas para sua determinação foram validadas. As condições cromatográficas utilizadas foram: coluna RP-18-octadecilsilano (250 x 4.6 mm, 5 mm), detecção em 238 nm, fase móvel contendo ácido fosfórico 0,1% e acetonitrila (35:65% v/v), fluxo de 1,5 mL min-1, temperatura do forno de 30 ºC e volume de injeção de 10 mL. ATV é classificada como um fármaco de classe II, de acordo com o sistema de classificação biofarmacêutica (SCB). Como tal, um teste de dissolução foi proposto para avaliar as formulações farmacêuticas do mercado atual, sob as seguintes condições: água como meio de dissolução, volume de 1000 mL, aparato pá, velocidade de rotação de 50 rpm, 80% (Q) em 15 minutos com leituras espectrofotômetro UV a 238 nm. Na condição padrão proposta para o teste de dissolução, o qual seria capaz de diferenciar apropriadamente as formulações farmacêuticas, o produto genérico não foi considerado equivalente farmacêutico. No entanto, em outros métodos de dissolução menos discriminativos, que também seriam considerados apropriados pelos parâmetros legais, este produto pode vir a ser considerado como genérico

    Call for emergency action to restore dietary diversity and protect global food systems in times of COVID-19 and beyond: Results from a cross-sectional study in 38 countries

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    Background: The COVID-19 pandemic has revealed the fragility of the global food system, sending shockwaves across countries' societies and economy. This has presented formidable challenges to sustaining a healthy and resilient lifestyle. The objective of this study is to examine the food consumption patterns and assess diet diversity indicators, primarily focusing on the food consumption score (FCS), among households in 38 countries both before and during the first wave of the COVID-19 pandemic. Methods: A cross-sectional study with 37 207 participants (mean age: 36.70 ± 14.79, with 77 % women) was conducted in 38 countries through an online survey administered between April and June 2020. The study utilized a pre-tested food frequency questionnaire to explore food consumption patterns both before and during the COVID-19 periods. Additionally, the study computed Food Consumption Score (FCS) as a proxy indicator for assessing the dietary diversity of households. Findings: This quantification of global, regional and national dietary diversity across 38 countries showed an increment in the consumption of all food groups but a drop in the intake of vegetables and in the dietary diversity. The household's food consumption scores indicating dietary diversity varied across regions. It decreased in the Middle East and North Africa (MENA) countries, including Lebanon (p < 0.001) and increased in the Gulf Cooperation Council countries including Bahrain (p = 0.003), Egypt (p < 0.001) and United Arab Emirates (p = 0.013). A decline in the household's dietary diversity was observed in Australia (p < 0.001), in South Africa including Uganda (p < 0.001), in Europe including Belgium (p < 0.001), Denmark (p = 0.002), Finland (p < 0.001) and Netherland (p = 0.027) and in South America including Ecuador (p < 0.001), Brazil (p < 0.001), Mexico (p < 0.0001) and Peru (p < 0.001). Middle and older ages [OR = 1.2; 95 % CI = [1.125–1.426] [OR = 2.5; 95 % CI = [1.951–3.064], being a woman [OR = 1.2; 95 % CI = [1.117–1.367], having a high education (p < 0.001), and showing amelioration in food-related behaviors [OR = 1.4; 95 % CI = [1.292–1.709] were all linked to having a higher dietary diversity. Conclusion: The minor to moderate changes in food consumption patterns observed across the 38 countries within relatively short time frames could become lasting, leading to a significant and prolonged reduction in dietary diversity, as demonstrated by our findings.Revisión por pare

    The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III

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    The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg2; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra. \ua9 2015. The American Astronomical Society

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
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