Strong solar flare events can occur even during the decay phase of the solar cycle. During these events concurrent increases in the X‐ray and Enhanced UV (EUV) fluxes and solar radio bursts (SRBs) ...can be observed. The SRBs cover a large range of frequencies including the L band, giving rise to signal fades in the GNSS carrier‐to‐noise ratio and fluctuations in its amplitude and phase. The increases in the X‐ray, UV, and EUV fluxes cause increase in the ionospheric D, E, and F region electron densities. The aim of this work is to analyze the effects in the GNSS signal, in the ionosphere and in the magnetic field H component of the X9.3 and X1.3 solar flares that occurred on 06 and 07 September 2017, respectively. Data from a network of six GNSS receivers, two magnetometers, and four Digisondes are used in the analysis. Fades of about 5 and 10 dB were observed in the signals of GNSS L1 and L2/L5 frequencies, respectively. Significant positioning errors, were observed for the strongest X9.3 flare. A sudden increase in Total Electron Content with the rates of 2.5–5.0 TECU/min was observed. An increase in the E layer density gave origin to an increase in the Equatorial Electrojet intensity, whose signatures were observed in the H component of two magnetometers. Another observed effect was the ionospheric D region density increase that caused disruption in the Digisonde signal. As a consequence of the described effects, GNSS receivers may fail to produce accurate navigation solution.
Key Points
Effects in the GNSS signal, in the ionosphere and in the magnetic field H component of the September 2017 X9.3 and X1.3 solar flares
Most of the low‐latitude ionospheric radar observations in South America come from the Jicamarca Radio Observatory, located in the western longitude sector (∼75°W). The deployment of the 30 MHz ...FAPESP‐Clemson‐INPE (FCI) coherent backscatter radar in the magnetic equatorial site of São Luis, Brazil, in 2001 allowed observations to be made in the eastern sector (∼45°W). However, despite being operational for several years (2001–2012), FCI only made observations during daytime and pre‐midnight hours, with a few exceptions. Here, we describe an upgraded system that replaced the FCI radar and present results of full‐night F‐region observations. This radar is referred to as Measurements of Equatorial and Low‐latitude Ionospheric irregularities over São Luís, South America (MELISSA), and made observations between March 2014 and December 2018. We present results of our analyses of pre‐ and post‐midnight F‐region echoes with focus on the spectral features of post‐midnight echoes and how they compare to spectra of echoes observed in the post‐sunset sector. The radar observations indicate that post‐midnight F‐region irregularities were generated locally and were not a result of “fossil” structures generated much earlier in time (in other longitude sectors) and that drifted into the radar field‐of‐view. This also includes cases where the echoes are weak and that would be associated with decaying equatorial spread F (ESF) structures. Collocated digisonde observations show modest but noticeable F‐region apparent uplifts prior to post‐midnight ESF events. We associate the equatorial uplifts with disturbed dynamo effects and with destabilizing F‐region conditions leading to ESF development.
Key Points
The MELISSA 30 MHz radar system is described and examples of F‐region observations are introduced
Results of the spectral analysis of pre‐ and post‐midnight F‐region echoes are presented and compared
Results indicate the local development of F‐region irregularities in the post‐midnight sector
Foam concrete stands out among special concrete for presenting a porous structure by incorporating foam into the cement matrix. The tendency for bubbles to coalesce and collapse during preparation ...poses some challenges in production and control over the properties of cell structures. This research aims to evaluate the behavior of cellular concrete using ultra-lightweight expanded polystyrene aggregate (EPS) as a source for reducing specific mass. Since, there are few publications investigating the integration of EPS pearls in foam concrete. For comparison, samples were made with Portland cement and quartz aggregate using the dosage method proposed by Ferreira (1987) for foamed concrete. In these concretes, properties in the plastic state were evaluated, compressive strength and ultrasonic wave propagation velocity tests were carried out at 3, 7, and 28 days and, in addition to these tests, at 28 days, the absorption, thermogravimetric analysis, and X-ray diffraction were carried out, under three water/binder factors: 0.38, 0.42 and 0.46. The results showed an apparent specific mass below 750 kg/m
3
and mechanical strength of up to 1 MPa. The replacement of expanded polystyrene promoted an average reduction in mass over the volume of around 30%. Making the technology more commercial for the use of thermal and acoustic insulators requires further studies to improve the product. In general, EPS aggregate is a viable and advantageous alternative when applied to cellular concrete from the point of view of the civil construction industry.
ABSTRACT Knowledge regarding the static pressure drop in granular layers is of fundamental importance in the development of efficient drying and aeration projects of agricultural products. Thus, the ...objective of this study was to evaluate the effects of impurity contents on the static pressure drop in different bed depth of castor bean grains, as well as modify the mathematical models per the obtained experimental data and select the model that best represents this phenomenon. First, impurities in castor bean grains of the Guarani variety were eliminated and 6% of the moisture content (dry basis) was retained. The coarse impurity contents were obtained with 2%, 4%, and 6% of mass addition. The pressure drop in different bed depth of clean and impure castor bean grains were determined using an experimental determination equipment of pressure drop in bed depth with an airflow rate ranging 0.2 - 1.0 m3 s−1 m−2. The pressure drop linearly increases with an increase in the depth of the grain layer, and the increase in the airflow rate leads to an increased pressure drop in the castor bean grains layer. The impurity contents increase causes a reduction in pressure drop. The models that best represent castor beans grains pressure drop experimental data, without and with impurities, are Hukill & Ives (1955) and Nimkar & Chattopadhyay (2002), respectively.
Babassu cake (BC) is a byproduct from oil extraction from babassu palm kernels. The aim of this study is to evaluate the effect of including BC levels (0%, 6%, 12%, and 18% on a dry matter basis) in ...the diet of 28 kids (n = 7 per treatment) on productive performance, and quality and profile of fatty acids (FA) of meat (loin). The inclusion of BC in the diet increases dry matter intake (P = 0.0005), average daily gain (P = 0.0222), slaughter body weight (P = 0.0424) of goats, and increased fat (P = 0.0424), unsaturated fatty acids (P = 0.0041), monounsaturated fatty acids (P = 0.0163), and isomers of conjugated linoleic acid (rumenic acid; P = 0.0002) content and polyunsaturated fatty acids:saturated fatty acids ratio (P = 0.0430) of meat. However, there are reductions in the levels of stearic acid (P < 0.0001) and saturated fatty acids (P = 0.0041) and in the thrombogenicity index (P = 0.0219) of meat. The inclusion of BC in the goat diet improves its growth performance and the quality and fatty acid profile of meat.
Babassu cake is used to feed goats. After feedlot, animals are slaughtered and the loin is evaluated for physical–chemical analysis and fatty acid profile. The inclusion 18% babassu cake improves the profile of fatty acids and increases marbling in goat meat.
•Freezers have worse sleep quality, cognition, anxiety and mobility.•Poor sleep quality and severity of freezing of gait are associated.•Cognition, anxiety and mobility predicted poor sleep quality ...in freezers.•Poor sleep quality may contribute to freezing of gait phenotype.
Individuals with Parkinson's disease (PD) who report freezing of gait (FOG) have poorer sleep quality than those without FOG. Cognitive, anxiety, and mobility disability are components of the FOG phenotype, however, no study has investigated if poor sleep quality is associated with all three components that underlie FOG in PD.
Are there associations among sleep quality and all three components of the FOG phenotype?
Forty and 39 individuals with and without FOG (PD + FOG and PD-FOG), respectively, and 31 age-matched healthy controls (HC) participated in this study. Self-reported FOG (new-FOG questionnaire-NFOGQ), sleep quality (Pittsburgh Sleep Quality Index-PSQI), cognitive function (Montreal Cognitive Assessment-MoCA), anxiety (subscale from Hospital Anxiety and Depression Scale-HADS-A), and mobility (timed-up-and-go test-TUG) were assessed.
PSQI scores were correlated with the scores of NFOGQ, MoCA, HADS-A, and TUG time in PD + FOG (P ≤ 0.0038). The multiple regression analysis identified the PSQI scores as the only predictor of the variance of the NFOGQ scores (R2 = 0.46, P < .0001). The variance in the PSQI scores were explained (69 %) by MoCA scores, NFOGQ scores, TUG time, and HADS-A scores (P ≤ 0.05). Although PD + FOG had a higher disease severity compared to PD-FOG (P < 0.001), disease severity did not enter in the regression model to explain PSQI scores and NFOGQ scores. We also observed associations of PSQI scores with the MoCA scores and TUG time for HC (P ≤ 0.0038), whereas there was no association between PSQI scores and any variable in PD-FOG (P > 0.05). Finally, PD + FOG presented worse scores of PSQI, MoCA, HADS-A, and TUG time than PD-FOG and HC (P < 0.05). Thus, poor sleep quality is associated with FOG and all three components that underlie FOG, regardless of the disease severity. Therefore, treatments useful to decrease FOG should be targeted to ameliorate sleep quality, cognition, anxiety, and mobility.
To determine the efficacy of tranilast as an adjunctive therapy in conjunctival autograft.
Twenty-nine patients were randomly allocated to the Tranilast Group (n=15) or the Control Group (n=14). The ...Tranilast Group received a subconjunctival injection of 0.5% tranilast 30 days prior to surgery. Conjunctival autograft was performed in both groups using fibrin sealant and 0.02% subconjunctival mitomycin C at the end of the surgery. After the resection of the pterygium, immunohistochemistry was performed with 100 cells to identify epithelial cells positive for transforming growth factor-β (TGF-β). Subjective symptoms were evaluated using a 5-point scale, and the recurrence rate was assessed.
Both groups showed improvements in their symptoms and similar clinical results. Compared with the Control Group, the Tranilast Group failed to show a decreased recurrence rate (p=0.59). However, the number of epithelial cells expressing TGF-β was lower in the Tranilast Group (5 cells; 95% CI: 2.56-13.15; Control Group, 16 cells, 95% CI: 11.53-24.76; p=0.01). Minimal but reversible complications, including glaucoma secondary to corticosteroids and granuloma, occurred during the study.
Tranilast was effective in decreasing the number of pterygium epithelial cells expressing TGF-β.
The remnants of the Atlantic Forest in Brazil are significant for biodiversity and provide benefits for people (climate regulation, water supply, health and welfare, among others). However, nature’s ...importance for different people may vary, for social, environmental, and economic reasons. In this paper, we explore such differences among people living in communities surrounding the Cunhambebe State Park (PEC), a large area of Atlantic Forest. We assess their perceptions regarding the plural values of ecosystem services derived from the PEC and explore ways in which this could affect the management of this protected area. Our assumption is that analyzing the perceptions of people who live in the communities surrounding can be a key tool for the formulation of proposals to improve management models and address socio-environmental conflicts. Based on interviews, participant observation, and document analysis, our results show a direct link between culture and environment since relational values and cultural ecosystem services are closely related to local people’s valuation of the PEC. Therefore, we support management strategies which are based on local values for land and forest use in a sustainable way. Our findings may contribute to decision making by PEC managers, governments, local stakeholders, and researchers.
Comportamento mecânico dos grãos de feijão submetidos a compressão Resende, Osvaldo(UFV CENTREINAR); Corrêa, Paulo C.(UFV DEA); Ribeiro, Deise M.(UFV CENTREINAR) ...
Revista Brasileira de Engenharia Agrícola e Ambiental,
2007, Letnik:
11, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Verificar a influência do teor de água nos valores da força máxima de compressão para deformações fixas e determinar o módulo proporcional de deformidade de grãos de feijão submetidos a compressão em ...três diferentes posições, foram os principais objetivos que estimularam o presente trabalho. Para isto, utilizaram-se grãos de feijão com teores de água variando de 0,13 a 0,45 (b.s.) comprimidos uniaxicialmente, entre duas placas paralelas, na direção de suas três dimensões essenciais. A partir dos resultados obtidos, conclui-se que a força de compressão necessária para deformar o feijão diminui com o aumento do teor de água, sendo maior para a direção perpendicular à divisão dos cotilédones (posição natural de repouso). O módulo proporcional de deformidade aumenta com a redução do teor de água e da deformação do produto, obtendo-se valores para a faixa de umidade estudada, entre 1,7 x 10(7) a 71,3 x 10(7) Pa, dependendo da posição do grão.
This work aims to determine the effect of soybean grain moisture content upon the maximum compression force values for fixed deformations and to determine the proportional deformity modulus under different compression positions. Edible beans with 0.45 to 0.13 (d.b.) moisture content were compressed uniaxialy between two parallel plates towards their three main axes. From the results it was concluded that the compression force decreased with moisture content increase, and the highest value corresponded to the direction perpendicular to cotyledon division (repose position). The proportional deformity modulus increases with the reduction of moisture content and with the deformation of the product, presenting values, for the studied moisture content, between 1.7 x 10(7) to 71.3 x 10(7) Pa, depending on grain position.
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