The proximate composition and fatty acid profile of five lots of samples of raw and roasted salt-dried sardines (Sardi-nella brasiliensis) bought locally in Maringá, Paraná State, Brazil were determined. Sig...The proximate composition and fatty acid profile of five lots of samples of raw and roasted salt-dried sardines (Sardi-nella brasiliensis) bought locally in Maringá, Paraná State, Brazil were determined. Significant differences (P < 0.05) were observed between samples of raw and roasted sardines, both in relation to moisture, total lipids, proteins, and ashes. The major fatty acids in raw and roasted sardine samples were docosahexaenoic acid (DHA, 22: 6n-3, 35.98%, 12.46%);palmitic acid (16: 0, 37.59%;24.18%), and eicosapentaenoic acid (EPA, 20: 5n-3, 6.62%;2.95%), respec-tively. The ratios of polyunsaturated to saturated fatty acid (PUFA/SFA) were 1.32 and 0.33, and the n-6/n-3 ratios were 0.07 and 0.13 in raw and roasted sardines, respectively. The results showed that roasting increased the SFA and reduced the PUFA in sardines, which still were rich in PUFA and remained a low-cost and nutritionally healthy food.展开更多
Fatty acid methyl ester (FAME) preparation is an important step to determine fatty acid composition of oils and fats. Transesterification with boron trifluoride (BF3) in methanol has been widely used;however, the tran...Fatty acid methyl ester (FAME) preparation is an important step to determine fatty acid composition of oils and fats. Transesterification with boron trifluoride (BF3) in methanol has been widely used;however, the transesterification of triacylglycerols usually involves a long heating time, whereas much shorter reaction times may be sufficient when microwave irradiation is used. The purpose of this paper was to optimize FAME preparation with BF3 by microwave irradiation. A three-factor central composite routable (CCRD) design was used to study the effect of the heating time (A), irradiation power (B), and volume of sodium hydroxide (C) on FAME concentration. A second-order polynomial model was employed to generate a surface response. Optimum conditions obtained for FAME preparation were time of 60 s, irradiation power of 220 W, and base volume of 1.5 mL. Compared to conventional methods, the advantages of this method are the quick result and the accuracy.展开更多
To investigate the influence of pressure and temperature on the jet velocity of a three-dimensional flow was the main goal of this study. Using a precipitation chamber with approximate capacity of 600 mL, it was studi...To investigate the influence of pressure and temperature on the jet velocity of a three-dimensional flow was the main goal of this study. Using a precipitation chamber with approximate capacity of 600 mL, it was studied the thermodynamic behavior of supercritical carbon dioxide mixture, dichloromethane and grape seed extract via SAS (supercritical antisolvent process). For the numerical solution, the Navier-Stokes equations were used along with the model of turbulence k-ε and Peng-Robinson equation of state with quadratic mixing rules of Van der Waals. The method of Chung was employed to determine the viscosity, thermal conductivity and mass diffusivity of the flow numerically solved through commercial code based on CFD (computational fluid dynamics). Simulations for pressures between 80 bar and 160 bar and temperatures between 308.15 K and 318.15 K showed large variations in the jet velocity, an important property in the dynamic mixing process that involves the size, size distribution and particle morphology.展开更多
The main goal of this study is analysis the mechanical behavior, failure mode and deflections of masonry beams lintels when subjected to concentrated loading. Walls were built using hollow clay blocks, using horizonta...The main goal of this study is analysis the mechanical behavior, failure mode and deflections of masonry beams lintels when subjected to concentrated loading. Walls were built using hollow clay blocks, using horizontal reinforcement on bed joint, and using of Murfor steel reinforcement. The conclusions of this work was: at middle of span, the load and displacement results present a linear behavior until failure; there two regions of failure, the region "A" presents the association of crushing and the region "B" shows the shear stress between block and mortar; the visual analysis of experimental tests shows the lost of adhesion between the mortar joint and blocks. It was not observed cracks on the mid-span produced by bending; it is possible to detach that the use of plane truss in Brazil as technological alternative is feasible and makes the masonry walls execution more rational, increasing the velocity of production.展开更多
This study validated different extraction methodologies and compared the quantification of cholesterol by gas chromatography (GC) and high performance liquid chromatography (HPLC) in mg per 100 g of Italian-type salam...This study validated different extraction methodologies and compared the quantification of cholesterol by gas chromatography (GC) and high performance liquid chromatography (HPLC) in mg per 100 g of Italian-type salami and traditional bologna. The GC method used was direct saponification of the samples without derivatizations and the HPLC method was used to extract of the lipid samples. The GC limits of detection and quantification obtained for cholesterol were, respectively, 0.001 and 0.003 mg.g–1. The HPLC values were 0.005 mg.g–1 and 0.016 mg.g–1. The GC recovery rate was 97.10 ± 0.13 and that of HPLC was 93.33 ± 0.22. Comparison of the cholesterol quantity found using the two chromatographic techniques shows that both are capable of quantifying cholesterol in the foods. With regard to costs, analysis time, the cost/benefit relationship was better with gas chromatography than that obtained with high performance liquid chromatography.展开更多
Frequency domain analyses in electromyographic (EMG) signals are frequently applied to assess muscle fatigue and similar variables. Moreover, Fourier-based approaches are typically used for investigating these procedu...Frequency domain analyses in electromyographic (EMG) signals are frequently applied to assess muscle fatigue and similar variables. Moreover, Fourier-based approaches are typically used for investigating these procedures. Nonetheless, Fourier analysis assumes the signal as stationary which is unlikely during dynamic contractions. As an alternative method, wavelet-based treatments do not assume this pattern and may be considered as more appropriate for joint time-frequency domain analysis. Based on the previous statements, the purpose of the present study was to compare the application of Short-Time Fourier Transform (STFT) and Continuous Wavelet Transform (CWT) to assess muscle fatigue in dynamic exercise of a 1-km of cycling (time-trial condition). The results of this study indicated that CWT and STFT analyses have provided similar fatigue estimates (slope) (p> 0.05). However, CWT application represents lesser dispersion (p< 0.05) for vastus medialis (189.9 ± 82.1 for STFT vs 148.6 ± 60.2 for CWT) and vastus lateralis (151.6 ± 49.6 for STFT vs 103.5 ± 27.9 for CWT). In conclusion, despite the EMG signal did not change (p> 0.05) according to different methods, it is important to note that these responses seem to show greater values for CWT compared to STFT for 2 superficial muscles. Thereby, we are capable of considering CWT as a reliable and useful method to take into consideration when non-stationary or oscillating exercise models are evaluated.展开更多
This study aimed to understand bark thickness variations of Araucaria angustifolia(Bertol.)Kuntze trees growing in natural forest remnants in southern Brazil,and their relationship with quantitative and qualitative at...This study aimed to understand bark thickness variations of Araucaria angustifolia(Bertol.)Kuntze trees growing in natural forest remnants in southern Brazil,and their relationship with quantitative and qualitative attributes.Bark thickness must be accurately estimated in order to determine timber volume stocks.This is an important variable for the sustainable management and conservation of araucaria forests.In spite of its importance and visibility,bark thickness variations have not been evaluated for this key species in southern Brazil.A total of 104 trees were selected,and their qualitative and quantitative attributes such as diameter at breast height(D_(BH)),height(H),crown base height(C_(BH)),crown length(C_(L)),social position(S_(P)),stoniness(S_(T)),position on the relief(P_(R)),vitality(V_T)and branch arrangement(B_(A))were measured.The trees were categorized into two groups:red bark or gray bark.Regression analysis and artificial neural networks(ANN)were used for modelling bark thickness.The results indicate that:(1)bark thickness showed good correlation to D_(BH),with 0.76 as coefficient of determination(RS_P),0.540 as Mean Absolute Error(M_(AE))and 22.4 root-meansquare error in percentage(R_(MSE%));(2)the trend changed according to bark colour,with significant differences for the intersection(_0–Pr>F:p=0.0124)and slope(β_(1)–Pr>F:p=0.0126)of bark thickness curves between groups;(3)the highest correlation of bark thickness was found with:D_(BH)(ρ=0.88),H(ρ=0.58),C_(BH)(ρ=0.46),S_(P)(ρ=-0.52),and B_(A)(ρ=-0.32);(4)modelling with ANN confirmed high adjustment(R^(2)=0.99)and accuracy(R_(MSE%)=3.0)of the estimates.ANN is an efficient and robust technique for the modelling of various qualitative and quantitative attributes commonly used in forest mensuration.The effective use of ANN to estimate araucaria bark in natural forests reinforces its potential,besides the possibility of application for other forest species.展开更多
Increasingly,scientists and non-scientists,especially employees of government agencies,tend to use weak or equivocal language when making statements related to science policy and governmental regulation.We use recent ...Increasingly,scientists and non-scientists,especially employees of government agencies,tend to use weak or equivocal language when making statements related to science policy and governmental regulation.We use recent publications to provide examples of vague language versus examples of strong language when authors write about regulating anthropogenic pressures on natural resources.Lifeless language is common in agency reports,policy documents,and even scientific papers published by academics.Such language limits success in regulating anthropogenic pressures on natural resources.This challenge must be recognized and countered as a driver of the condition of water and associated resources.We also list sources of vague wording,provide global examples of how ambiguous language and political influences have contributed to water resource degradation,discuss the recent history of science censorship,and offer possible solutions for more direct scientific discourse.We found that:(1)equivocal language was especially common in concluding statements and not only by government employees;(2)authors discussed confusing language concerns in an agency publication;and(3)agency employees sometimes used active,strong language.Key drivers of weak language include:(1)holding on to old paradigms and resisting new knowledge;(2)scientific uncertainty;(3)institutional manuscript review policies;(4)employment and funding insecurity;and(5)avoiding the appearance of advocacy.Examples associated with euphemistic language included climate change,flow and physical habitat alteration,dams,agriculture,mining,forestry,and fisheries,as well as resistance towards monitoring,assessing,and reporting ecological conditions.Suggestions for mitigating equivocal language involve employment protections and greater focus on scientific ethics.We conclude that natural resource scientists should resist calls to employ imprecise language.Instead,they should be strong advocates for prescriptive and protective natural resource actions—based on their science—to halt and reverse the systemic degradation of those resources.展开更多
文摘The proximate composition and fatty acid profile of five lots of samples of raw and roasted salt-dried sardines (Sardi-nella brasiliensis) bought locally in Maringá, Paraná State, Brazil were determined. Significant differences (P < 0.05) were observed between samples of raw and roasted sardines, both in relation to moisture, total lipids, proteins, and ashes. The major fatty acids in raw and roasted sardine samples were docosahexaenoic acid (DHA, 22: 6n-3, 35.98%, 12.46%);palmitic acid (16: 0, 37.59%;24.18%), and eicosapentaenoic acid (EPA, 20: 5n-3, 6.62%;2.95%), respec-tively. The ratios of polyunsaturated to saturated fatty acid (PUFA/SFA) were 1.32 and 0.33, and the n-6/n-3 ratios were 0.07 and 0.13 in raw and roasted sardines, respectively. The results showed that roasting increased the SFA and reduced the PUFA in sardines, which still were rich in PUFA and remained a low-cost and nutritionally healthy food.
文摘Fatty acid methyl ester (FAME) preparation is an important step to determine fatty acid composition of oils and fats. Transesterification with boron trifluoride (BF3) in methanol has been widely used;however, the transesterification of triacylglycerols usually involves a long heating time, whereas much shorter reaction times may be sufficient when microwave irradiation is used. The purpose of this paper was to optimize FAME preparation with BF3 by microwave irradiation. A three-factor central composite routable (CCRD) design was used to study the effect of the heating time (A), irradiation power (B), and volume of sodium hydroxide (C) on FAME concentration. A second-order polynomial model was employed to generate a surface response. Optimum conditions obtained for FAME preparation were time of 60 s, irradiation power of 220 W, and base volume of 1.5 mL. Compared to conventional methods, the advantages of this method are the quick result and the accuracy.
文摘To investigate the influence of pressure and temperature on the jet velocity of a three-dimensional flow was the main goal of this study. Using a precipitation chamber with approximate capacity of 600 mL, it was studied the thermodynamic behavior of supercritical carbon dioxide mixture, dichloromethane and grape seed extract via SAS (supercritical antisolvent process). For the numerical solution, the Navier-Stokes equations were used along with the model of turbulence k-ε and Peng-Robinson equation of state with quadratic mixing rules of Van der Waals. The method of Chung was employed to determine the viscosity, thermal conductivity and mass diffusivity of the flow numerically solved through commercial code based on CFD (computational fluid dynamics). Simulations for pressures between 80 bar and 160 bar and temperatures between 308.15 K and 318.15 K showed large variations in the jet velocity, an important property in the dynamic mixing process that involves the size, size distribution and particle morphology.
文摘The main goal of this study is analysis the mechanical behavior, failure mode and deflections of masonry beams lintels when subjected to concentrated loading. Walls were built using hollow clay blocks, using horizontal reinforcement on bed joint, and using of Murfor steel reinforcement. The conclusions of this work was: at middle of span, the load and displacement results present a linear behavior until failure; there two regions of failure, the region "A" presents the association of crushing and the region "B" shows the shear stress between block and mortar; the visual analysis of experimental tests shows the lost of adhesion between the mortar joint and blocks. It was not observed cracks on the mid-span produced by bending; it is possible to detach that the use of plane truss in Brazil as technological alternative is feasible and makes the masonry walls execution more rational, increasing the velocity of production.
文摘This study validated different extraction methodologies and compared the quantification of cholesterol by gas chromatography (GC) and high performance liquid chromatography (HPLC) in mg per 100 g of Italian-type salami and traditional bologna. The GC method used was direct saponification of the samples without derivatizations and the HPLC method was used to extract of the lipid samples. The GC limits of detection and quantification obtained for cholesterol were, respectively, 0.001 and 0.003 mg.g–1. The HPLC values were 0.005 mg.g–1 and 0.016 mg.g–1. The GC recovery rate was 97.10 ± 0.13 and that of HPLC was 93.33 ± 0.22. Comparison of the cholesterol quantity found using the two chromatographic techniques shows that both are capable of quantifying cholesterol in the foods. With regard to costs, analysis time, the cost/benefit relationship was better with gas chromatography than that obtained with high performance liquid chromatography.
文摘Frequency domain analyses in electromyographic (EMG) signals are frequently applied to assess muscle fatigue and similar variables. Moreover, Fourier-based approaches are typically used for investigating these procedures. Nonetheless, Fourier analysis assumes the signal as stationary which is unlikely during dynamic contractions. As an alternative method, wavelet-based treatments do not assume this pattern and may be considered as more appropriate for joint time-frequency domain analysis. Based on the previous statements, the purpose of the present study was to compare the application of Short-Time Fourier Transform (STFT) and Continuous Wavelet Transform (CWT) to assess muscle fatigue in dynamic exercise of a 1-km of cycling (time-trial condition). The results of this study indicated that CWT and STFT analyses have provided similar fatigue estimates (slope) (p> 0.05). However, CWT application represents lesser dispersion (p< 0.05) for vastus medialis (189.9 ± 82.1 for STFT vs 148.6 ± 60.2 for CWT) and vastus lateralis (151.6 ± 49.6 for STFT vs 103.5 ± 27.9 for CWT). In conclusion, despite the EMG signal did not change (p> 0.05) according to different methods, it is important to note that these responses seem to show greater values for CWT compared to STFT for 2 superficial muscles. Thereby, we are capable of considering CWT as a reliable and useful method to take into consideration when non-stationary or oscillating exercise models are evaluated.
基金This study is supported by the Graduate Program in Forest Engineering of the Santa Catarina State University(UDESC)the Santa Catarina Research Foundation(FAPESC+3 种基金2017TR1762,2017TR639,2019TR816)the Brazilian National Council for Scientifi c and Technological Development(CNPq313887/2018-7)the Coordination for the Improvement of Higher Education Personnel(CAPES).
文摘This study aimed to understand bark thickness variations of Araucaria angustifolia(Bertol.)Kuntze trees growing in natural forest remnants in southern Brazil,and their relationship with quantitative and qualitative attributes.Bark thickness must be accurately estimated in order to determine timber volume stocks.This is an important variable for the sustainable management and conservation of araucaria forests.In spite of its importance and visibility,bark thickness variations have not been evaluated for this key species in southern Brazil.A total of 104 trees were selected,and their qualitative and quantitative attributes such as diameter at breast height(D_(BH)),height(H),crown base height(C_(BH)),crown length(C_(L)),social position(S_(P)),stoniness(S_(T)),position on the relief(P_(R)),vitality(V_T)and branch arrangement(B_(A))were measured.The trees were categorized into two groups:red bark or gray bark.Regression analysis and artificial neural networks(ANN)were used for modelling bark thickness.The results indicate that:(1)bark thickness showed good correlation to D_(BH),with 0.76 as coefficient of determination(RS_P),0.540 as Mean Absolute Error(M_(AE))and 22.4 root-meansquare error in percentage(R_(MSE%));(2)the trend changed according to bark colour,with significant differences for the intersection(_0–Pr>F:p=0.0124)and slope(β_(1)–Pr>F:p=0.0126)of bark thickness curves between groups;(3)the highest correlation of bark thickness was found with:D_(BH)(ρ=0.88),H(ρ=0.58),C_(BH)(ρ=0.46),S_(P)(ρ=-0.52),and B_(A)(ρ=-0.32);(4)modelling with ANN confirmed high adjustment(R^(2)=0.99)and accuracy(R_(MSE%)=3.0)of the estimates.ANN is an efficient and robust technique for the modelling of various qualitative and quantitative attributes commonly used in forest mensuration.The effective use of ANN to estimate araucaria bark in natural forests reinforces its potential,besides the possibility of application for other forest species.
文摘Increasingly,scientists and non-scientists,especially employees of government agencies,tend to use weak or equivocal language when making statements related to science policy and governmental regulation.We use recent publications to provide examples of vague language versus examples of strong language when authors write about regulating anthropogenic pressures on natural resources.Lifeless language is common in agency reports,policy documents,and even scientific papers published by academics.Such language limits success in regulating anthropogenic pressures on natural resources.This challenge must be recognized and countered as a driver of the condition of water and associated resources.We also list sources of vague wording,provide global examples of how ambiguous language and political influences have contributed to water resource degradation,discuss the recent history of science censorship,and offer possible solutions for more direct scientific discourse.We found that:(1)equivocal language was especially common in concluding statements and not only by government employees;(2)authors discussed confusing language concerns in an agency publication;and(3)agency employees sometimes used active,strong language.Key drivers of weak language include:(1)holding on to old paradigms and resisting new knowledge;(2)scientific uncertainty;(3)institutional manuscript review policies;(4)employment and funding insecurity;and(5)avoiding the appearance of advocacy.Examples associated with euphemistic language included climate change,flow and physical habitat alteration,dams,agriculture,mining,forestry,and fisheries,as well as resistance towards monitoring,assessing,and reporting ecological conditions.Suggestions for mitigating equivocal language involve employment protections and greater focus on scientific ethics.We conclude that natural resource scientists should resist calls to employ imprecise language.Instead,they should be strong advocates for prescriptive and protective natural resource actions—based on their science—to halt and reverse the systemic degradation of those resources.