Uso de agrotóxicos no sistema de produção de hortaliças no Município de Camocim de São Félix, Pernambuco.

A falta de informacoes sobre as medidas de seguranca nas aplicacoes dos agrotoxicos predomina no meio rural, resultando na degradacao dos recursos naturais, com implicacoes diretas na saude humana. Visando suprir a ausencia de informacoes sobre o uso e manejo de agrotoxicos do municipio de Camocim de Sao Felix (PE), foram realizadas entrevistas com agricultores sobre aspectos pessoais, condicoes de trabalho, principais agrotoxicos utilizados e aspectos ambientais. Dentre os agrotoxicos mais usados, foram selecionados o Metamidofos e o Captan para analise de residuos em agua. Com base nos resultados, verificou-se que o nivel de escolaridade entre os entrevistados e muito baixo. Eles desconhecem o receituario agronomico, nao obedecem o periodo de carencia e, em geral, nao usam medidas de seguranca durante o manuseio, a aplicacao e mesmo apos a aplicacao dos agrotoxicos. Semanalmente e as vezes ate menos, aplicam inseticidas e/ou fungicidas, em carater preventivo e em doses excessivas, nao importando as consequencias para o aplicador e muito menos para o consumidor. No ano de 1997, os inseticidas mais utilizados foram os organofosforados e os piretroides. Com relacao aos fungicidas, o ditiocarbamato (Mancozeb) e o Captan foram os mais empregados. No periodo de setembro a novembro de 1997, foram detectados residuos dos agrotoxicos Metamidofos e Captan em agua de cacimba e de acude, com concentracoes acima do limite de padrao de potabilidade, o que indica agua impropria para consumo.bitstream/item/62533/1/CNPS-BOL.-PESQ.-6-99.pd

Lithography-Free, Omnidirectional, CMOS-Compatible AlCu Alloys for Thin-Film Superabsorbers

Superabsorbers based on metasurfaces have recently enabled the control of light at the nanoscale in unprecedented ways. Nevertheless, the sub‐wavelength features needed to modify the absorption band usually require complex fabrication methods, such as electron‐beam lithography. To overcome the scalability limitations associated with the fabrication of metallic nanostructures, engineering the optical response of superabsorbers by metal alloying is proposed, instead of tuning the geometry/size of the nanoscale building blocks. The superior performance of thin film AlCu alloys as the metallic component of planar bilayer superabsorbers is numerically demonstrated. This alloy outperforms its pure constituents as well as other metals, such as Ag, Au, and Cr. As a model system, a Si/AlCu structure is analyzed that presents \u3e99% absorption at selected wavelength ranging from the visible to the near‐infrared regions of the spectrum, depending on the subwavelength thickness of the semiconductor. The multi‐wavelength near‐unity absorption behavior of Si/AlCu persists even for oblique angle of incidence, up to 70°. Additionally, the findings are validated by fabricating and testing a‐Si/AlCu superabsorbers, where good agreement is found between the numerically and experimentally determined optical response. The system investigated here is relevant for integration in complementary metal‐oxide‐semiconductor (CMOS) technologies

Physical quality of a yellow latossol under integrated crop-livestock system.

Soil physical quality is essential to global sustainability of agroecosystems, once it is related to processes that are essential to agricultural crop development. This study aimed to evaluate physical attributes of a Yellow Latossol under different management systems in the savanna area in the state of Piaui. This study was developed in Uruçuí southwest of the state of Piauí. Three systems of soil management were studied: an area under conventional tillage (CT) with disk plowi and heavy harrow and soybean crop; an area under no-tillage with soybean-maize rotation and millet as cover crop (NT + M); two areas under Integrated Crop-Livestock System, with five-month pasture grazing and soybean cultivation and then continuous pasture grazing (ICL + S and ICL + P, respectively). Also, an area under Native Forest (NF) was studied. The soil depths studied were 0.00-0.05, 0.05-0.10 and 0.10-0.20 m. Soil bulk density, as well as porosity and stability of soil aggregates were analyzed as physical attributes. Anthropic action has changed the soil physical attributes, in depth, in most systems studied, in comparison to NF. In the 0.00 to 0.05 m depth, ICL + P showed higher soil bulk density value. As to macroporosity, there was no difference between the management systems studied and NF. The management systems studied changed the soil structure, having, as a result, a small proportion of soil in great aggregate classes (MWD). Converting native forest into agricultural production systems changes the soil physical quality. The Integrated Crop-Livestock System did not promote the improvement in soil physical quality

Profile of isoflavones in genetically modified soy.

Isoflavones are important compounds in soy with functional claims. Their concentrations are influenced by growing conditions and genetics. With the development of genetically modified varieties is crucial to know the levels of these substances in new seeds. Analyzed in six transgenic soybean cultivars (BRS-FavoritaRR, BRS-ValiosaRR, BRSMG-850GRR, BRSMG-811CRR, BRSMG-750SRR and BRSMG-740SRR) isoflavones (genistein, daidzein, and glycitein in their four chemical forms) by HPLC. The results were compared in mg/100g of dry and defatted samples. Statistical analysis was performed using Turkey test (p <0.05). Observed in the raw grain, the absence of detectable amounts of the isoflavones with acetyl radical, as well as the aglucone glycitein. The literature describes genistein aglycone as the most active and BRS-ValiosaRR showed a lower level and BRS-FavoritaRR the largest, not differing significantly from this variety BRSMG-750SRR for this analyte. The aglycone forms of daidzein is second in biological activity and varieties BRSMG-811CRR and BRS-ValiosaRR had lower grades and BRSMG 750SRR-and BRS-FavoritaRR the largest. The total isoflavones did not differ significantly between BRSMG-811CRR (413.86d) and BRSMG740-SRR (435.72d) but between these and BRSMG-750SRR (491.94c). The BRS-ValiosaRR (533.73b) was similar to BRSMG-850GRR (549.08b) but differed BRS-FavoritaRR (591.29a) that higher concentration. The BRS-FavoritaRR generally show the best performance while BRSMG-810CRR the worst. This knowledge is relevant in terms of both technology development (seed richest) and showing the quantity of food being consumed (considering the content of isoflavones)

Changes in choroidal thickness and retinal activity with a myopia control contact lens

Purpose: The axial elongation in myopia is associated with some structural and functional retinal changes. The purpose of this study was to investigate the effect of a contact lens (CL) intended for myopia control on the choroidal thickness (ChT) and the retinal electrical response. Methods: Ten myopic eyes (10 subjects, 18–35 years of age) with spherical equivalents from −0.75 to −6.00 diopters (D) were enrolled. The ChT at different eccentricities (3 mm temporal, 1.5 mm temporal, sub-foveal ChT, 1.5 mm nasal, and 3 mm nasal), the photopic 3.0 b-wave of ffERG and the PERG were recorded and compared with two material-matched contact lenses following 30 min of wear: a single-vision CL (SV) and a radial power gradient CL with +1.50 D addition (PG). Results: Compared with the SV, the PG increased the ChT at all eccentricities, with statistically significant differences at 3.0 mm temporal (10.30 ± 11.51 µm, p = 0.020), in sub-foveal ChT (17.00 ± 20.01 µm, p = 0.025), and at 1.5 mm nasal (10.70 ± 14.50 µm, p = 0.044). The PG decreased significantly the SV amplitude of the ffERG photopic b-wave (11.80 (30.55) µV, p = 0.047), N35-P50 (0.90 (0.96) µV, p = 0.017), and P50-N95 (0.46 (2.50) µV, p = 0.047). The amplitude of the a-wave was negatively correlated with the ChT at 3.0T (r = −0.606, p = 0.038) and 1.5T (r = −0.748, p = 0.013), and the amplitude of the b-wave showed a negative correlation with the ChT at 1.5T (r = −0.693, p = 0.026). Conclusions: The PG increased the ChT in a similar magnitude observed in previous studies. These CLs attenuated the amplitude of the retinal response, possibly due to the combined effect of the induced peripheral defocus high-order aberrations impacting the central retinal image. The decrease in the response of bipolar and ganglion cells suggests a potential retrograde feedback signaling effect from the inner to outer retinal layers observed in previous studies.This work was funded by the Portuguese Foundation for Science and Technology (FCT) in the framework of projects PTDC/FIS-OPT/0677/2014, the FCT Strategic Funding UID/FIS/04650/2013, FCT-SFRH/BPD/92365/2013 and SFRH/BD/136684/2018

Aprimoramento de protocolo de extração de DNA para duas espécies de palmeiras com o uso de diferentes antioxidantes.

O objetivo deste trabalho foi aperfeiçoar o protocolo de extração de DNA dessas duas espécies com o uso de diferentes antioxidantes.19º MET

Otimização do protocolo de extração de DNA de mandioca pela adição de diferentes antioxidantes.

19º MET