551 research outputs found

    Shoreline rate-of-change and setback line on adjacent areas of Sergipe river’s mouth, Aracaju, Sergipe

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    As praias dos Artistas e da Atalaia (porção norte), localizadas em Aracaju, Sergipe, estão sujeitas à atuação dos agentes costeiros (ondas, correntes e ventos) e da dinâmica da desembocadura do rio Sergipe. Nessas praias, no período de 2007 a 2008, ocorreram eventos erosivos severos que acarretaram na destruição de diversas estruturas antrópicas (praça de eventos, bares/restaurantes, etc.). Este trabalho teve como objetivo calcular a taxa de variação da linha de costa e a largura da faixa de proteção na área contígua à desembocadura do rio Sergipe após severa erosão ao sul. A metodologia consistiu em: (i) análise multitemporal (2008 a 2015) da linha de costa utilizando imagens de satélite e perfis de praia; (ii) cálculo da taxa de variação da linha de costa pelo método End Point Rate (EPR); (iii) determinação da largura de faixa de proteção. As taxas de recuo da linha de costa na área investigada, que variaram de -0,5 a -13 m/ano, permitiram sugerir o estabelecimento de duas faixas de proteção: 360 m para construções leves e 730 m para construções pesadas, respectivamente. As praias estudadas possuem estrutura de contenção à erosão, que não recebem manutenção sistematicamente. O problema de erosão em alguns pontos da área investigada não foi solucionado definitivamente devido à reincidência de eventos erosivos. Dessa forma, medidas preventivas, a exemplo da utilização de faixas de proteção recomendadas nesse trabalho devem ser incentivadas. Palavras-chave. análise multitemporal, erosão, taxa de recuo, medidas preventivas.The “Artistas” and “Atalaia” beaches, located in Aracaju, Sergipe, are subject to coastal processes (waves, currents and winds) and to Sergipe’s river mouth dynamics. From 2007 to 2008, severe erosive events, that led to the destruction of anthropogenic structures (events plaza, bars/restaurants, etc.), occurred on these beaches. This work aims to calculate the shoreline rate-of-change and the setback lines nearby Sergipe’s river mouth. The methodology consisted of: (i) historical analysis of shoreline positions using data from satellite images and beach profiles (from 2008 to 2015); (ii) calculation of the shoreline rate-of-change using the End Point Rate (EPR) statistics method; and (iii) determination of setback lines. Shoreline retreat rates in the investigated area, which ranged from -0.5 to -13 m/yr, allowed the establishment of two setback lines: 360 m for soft constructions and 730 m for hard constructions, respectively. The studied beaches present erosion protection structures, but they do not receive maintenance systematically. The erosion problem at some points was not solved definitively due to the recidivism of erosive events. Therefore, preventive measures, such as the use of setback lines recommended in this work, should be encouraged

    Magnetoliposomes incorporated in peptide-based hydrogels: towards development of magnetolipogels

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    A major problem with magnetogels is the encapsulation of hydrophobic drugs. Magnetoliposomes not only provide these domains but also improve drug stability and avert the aggregation of the magnetic nanoparticles. In this work, two magnetoliposome architectures, solid and aqueous, were combined with supramolecular peptide-based hydrogels, which are of biomedical interest owing to their biocompatibility, easy tunability, and wide array of applications. This proof-of-concept was carried out through combination of magnetoliposomes (loaded with the model drug curcumin and the lipid probe Nile Red) with the hydrogels prior to pH triggered gelation, and fluorescence spectroscopy was used to assess the dynamics of the encapsulated molecules. These systems allow for the encapsulation of a wider array of drugs. Further, the local environment of the encapsulated molecules after gelation is unaffected by the used magnetoliposome architecture. This system design is promising for future developments on drug delivery as it provides a means to independently modify the components and adapt and optimize the design according to the required conditions.FCT -Fundação para a Ciência e a Tecnologia(UIDB/00686/2020

    Assessment of Physical-Chemical Characteristics of Water and Sediments from a Brazilian Tropical Estuary: Status and Environmental Implications

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    The environmental quality of the Jacuípe River's estuary (very important in northeastern Brazil) was assessed during 2007 and 2008. In water, concentrations (mg L−1) of NO2− (<0.004 to 0.016), NO3− (0.01 to 0.33), soluble PO43− (<0.02 to 0.22), dissolved oxygen (3.9 to 9.6), total contents (mg L−1) of Cd (<0.001), Cu (<0.01), Pb (<0.01), and Zn (<0.1), pH (5.60 to 8.00), and electrical conductivity (0.12 to 48.60 mS cm−1) agreed with environmental standards. In sediments, clay and total organic matter (%, m/m) varied, respectively, from 8.8 to 12.0 and from 1.1 to 8.8, while infrared, thermogravimetric profile, electronic micrograph, as well as X-Ray analyses showed desirable adsorptive characteristics. However, maximum exchangeable levels (mg kg−1) of Cd (1.3), Cu (44.6), Pb (35.7), and Zn (43.7) and their respective maximum pseudototal concentrations (mg kg−1): 19.4, 95.1, 68.2, and 30.3 were below the recommended limits. In this sense, it was possible to demonstrate good environmental preservation even with the growing number of industries and touristic activities in the evaluated estuarine area

    Infection by Streptococcus pneumoniae in children with or without radiologically confirmed pneumonia

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    ObjectiveCommunity-acquired pneumonia is an important cause of morbidity in childhood, but the detection of its causative agent remains a diagnostic challenge. The authors aimed to evaluate the role of the chest radiograph to identify cases of community-aquired pneumonia caused by typical bacteria.MethodsThe frequency of infection by Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis was compared in non-hospitalized children with clinical diagnosis of community acquired pneumonia aged 2–59 months with or without radiological confirmation (n = 249 and 366, respectively). Infection by S. pneumoniae was diagnosed by the detection of a serological response against at least one of eight pneumococcal proteins (defined as an increase ≥2-fold in the IgG levels against Ply, CbpA, PspA1 and PspA2, PhtD, StkP-C, and PcsB-N, or an increase ≥1.5-fold against PcpA). Infection by H. influenzae and M. catarrhalis was defined as an increase ≥2-fold on the levels of microbe-specific IgG.ResultsChildren with radiologically confirmed pneumonia had higher rates of infection by S. pneumoniae. The presence of pneumococcal infection increased the odds of having radiologically confirmed pneumonia by 2.8 times (95% CI: 1.8–4.3). The negative predictive value of the normal chest radiograph for infection by S. pneumoniae was 86.3% (95% CI: 82.4–89.7%). There was no difference on the rates of infection by H. influenzae and M. catarrhalis between children with community-acquired pneumonia with and without radiological confirmation.ConclusionsAmong children with clinical diagnosis of community-acquired pneumonia submitted to chest radiograph, those with radiologically confirmed pneumonia present a higher rate of infection by S. pneumoniae when compared with those with a normal chest radiograph.</p

    Pneumonia and poverty: a prospective population-based study among children in Brazil

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    <p>Abstract</p> <p>Background</p> <p>Children in developing country suffer the highest burden of pneumonia. However, few studies have evaluated associations between poverty and pneumonia.</p> <p>Methods</p> <p>A prospective population-based study on pneumonia was carried out as part of the Latin America Epidemiological Assessment of Pneumococcus (LEAP study). Chest x-rays were obtained for children one to 35 months old with suspected pneumonia presenting to emergency care centers and hospital emergency rooms in Goiania, Brazil. Chest radiographs were evaluated according to WHO guidelines. Clustering of radiologically-confirmed pneumonia were evaluated using a Poisson-based spatial scan statistic. Associations between census socioeconomic indicators and pneumonia incidence rates were analyzed using generalized linear models.</p> <p>Results</p> <p>From May, 2007 to May, 2009, chest radiographs were obtained from 11 521 children with clinical pneumonia; 3955 episodes were classified as radiologically-confirmed. Incidence rates were significantly higher in very low income areas (4825.2 per 10<sup>5</sup>) compared to high income areas (1637.3 per 10<sup>5</sup>). Spatial analysis identified clustering of confirmed pneumonia in Western (RR 1.78; p = 0.001) and Southeast (RR 1.46; p = 0.001) regions of the city, and clustering of hospitalized pneumonia in the Western region (RR 1.69; p = 0.001). Lower income households and illiteracy were associated with pneumonia incidence.</p> <p>Conclusions</p> <p>In infants the risk of developing pneumonia is inversely associated with the head of household income and with the woman educational level. Areas with deprived socioeconomic conditions had higher incidence of pneumonia and should be targeted for high vaccination coverage.</p

    Evaluation of the Antimicrobial Activity of the Decoction of Tropidurus hispidus (Spix, 1825) and Tropidurus semitaeniatus (Spix, 1825) Used by the Traditional Medicine

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    Tropidurus hispidus and Tropidurus semitaeniatus are two lizard species utilized in traditional medicine in Northeast Brazil. Their medicinal use includes diseases related with bacterial infections such as tonsillitis and pharyngitis. They are used in the form of teas (decoctions) for the treatment of illnesses. In this work, we evaluated the antimicrobial activity of the decoctions of T. hispidus (DTH) and T. semitaeniatus (DTS) against bacterial strains, namely, standard and multiresistant Escherichia coli, Staphylococus aureus, and Pseudomonas aureuginosa, alone and in combination with aminoglycoside antibiotics. The decoctions were prepared using the whole body of the dried lizards, and the filtrate was frozen and lyophilized. When tested alone, the samples did not demonstrate any substantial inhibition of bacterial growth. However, in combination with antibiotics as aminoglycosides, decoctions reduced the minimal inhibitory concentration (MIC) of the assayed antibiotics against multiresistant strains of S. aureus and P. aureuginosa. Chemical prospecting tests revealed the presence of alkaloids in DTS. This is the first study evaluating the medicinal efficacy of T. hispidus and T. semitaeniatus and contributes to the list of new sources of medicines from natural products of animal origin
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