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The flapping kinematics have revealed a new paradigm of locomotion which is highly maneuverable and efficient compared to traditional propulsion systems. This work numerically investigates a three-dimensional wing undergoing pitching oscillations using Large eddy simulation (LES). The wake structure is presented using the Q -function, and the influence of pitching frequency on the structure of the wake is discussed. The vortices appear to travel as interconnected vortex rings in the bifurcated wake and are completely different from the two-dimensional investigations. The increase in pitching frequency ( St D) generates the interlinking structures between the two limbs of the bifurcated wake. The interlinking between the two limbs increases with St D and will get disrupted at sufficiently high St D . The increase in St D increased the force generated by the pitching wing, and the periodic dynamics between the force coefficients slowly transformed to quasi-periodic dynamics. The transition to quasi-periodic dynamics has not reduced the force generation of the pitching wing. The disruption of interlinking structures between the two limbs enhanced the lift generated by the pitching wing. The present investigation shows that the wake vortex structure strongly depends on St D . The generation of a jet in the wake is visible in the mean velocity profile indicating the thrust developed by the wing. The formation of multiple peak profiles indicated the formation of multiple jets, which resulted in enhanced thrust production. The Reynolds stress field generated from the velocity fluctuations appears to be influenced by both the pitching oscillations and vortex interactions. This study can guide the selection of better kinematic parameters to enhance the propulsive performance. [ABSTRACT FROM AUTHOR]

This study focuses on improving the performance of Savonius hydrokinetic turbines (SHTs) by analyzing the influence of blade aerodynamics and varying overlap ratios ( e D = 0 to 0.15). The study compares the performance of conventional and a new type of Savonius turbine blade, referred to as S R 5050. The study uses the incompressible SST k − ω model to evaluate the performance of a rotor under an upstream velocity of 0. 46 m s , with the numerical flow-driven approach where no artificial rotor motion has been provided. The results show that the new blade shape of the S R 5050 rotor outperforms conventional rotors in all e D ratios. The blade shape of the S R 5050 rotor effectively captures the energy of fluid passing between the blades, increasing both the coefficient of power C p and the coefficient of torque C m . The S R 5050 rotor with an e D ratio of 0.15 displays the highest value of C p at 0.38. It shows a maximum performance improvement of 39.19% over conventional rotors. For conventional rotors, the highest values of C m were observed at rotor position around ≈ 15 ° and ≈ 195 ° , while for S R 5050 rotors with all e D ratios, the highest values of C m were observed at rotor position of ≈ 20 ° and ≈ 200 °. [Display omitted] • Influence of aerodynamic blade shape (SR5050) on the SHT. • Influence of different overlap ratios on the SHT. • Increasing the overlap ratio results in higher mean value of the TSR, C m and C p. • The S R 5050 shows better starting characteristics. • The S R 5050 exhibited a 39.19% increase in C p = 0. 38 compared to the conventional rotor. [ABSTRACT FROM AUTHOR]

The three-dimensional flow around a custom wing performing pitching oscillation is analyzed numerically using large-eddy simulation with the wall adapting local eddy-viscosity subgrid-scale model. The wake characteristics behind the pitching wing with three different aspect ratios, AR = 2 / 3 , 1 , 4 / 3 , is investigated in an upstream flow with Reynolds number, Re = 2640. The Q − function is employed to identify the swirling structures in the flow field, and four primary vortices, namely, primary leading edge vortex (PLEV), secondary leading edge vortex, wing tip vortices, and trailing edge vortex, are identified. The evolution of vortices over the wing surface is presented in detail, and the arrangement of vortex rings in the wake is compared for three different aspect ratios. The PLEV develops into an arch vortex using the self-induction phenomenon, and the interlinking between the subsequent vortex rings depends on the arch vortex leaving the trailing edge. The force coefficient computed over the wing shows a positive thrust for AR = 4 / 3. The mean velocity field contours indicate a spanwise loading on the wing, which is unaccountable in two-dimensional studies. The Reynolds stresses generated due to large-scale periodic velocity fluctuations in the wake are presented. The vorticity field in the midplane of the wing appears to be diffusive at higher aspect ratios. The comparison of vorticity from the three-dimensional and two-dimensional models suggests that a two-dimensional model will over predict the vorticity distribution and force coefficients in the wake. [ABSTRACT FROM AUTHOR]

The application of a flapping wing mechanism offers a vast range of development possibilities for unmanned aerial vehicles (UAVs) and autonomous underwater vehicles (AUVs). The influence of wake transitions on flapping wing mechanism's capabilities is not fully understood particularly at low Reynolds numbers. The numerical investigation of a symmetric airfoil performing sinusoidal heaving oscillations is performed to explore the wake transitions. The influence of heaving parameters on wake transitions when exposed to a constant velocity flow is investigated. The existence of reverse von Karman vortex street, deflected wake and chaotic wake is observed. The wake deflection is found to switch its direction before transforming into a chaotic wake. The coherent structures and its evolution with the flow are presented using proper orthogonal decomposition (POD). The underlying structures and their interactions for different wake situations are identified. Correlations for the nondimensional maximum velocity in the wake in terms of frequency and amplitude is proposed. The wake dynamics is found to depend significantly on the leading edge vortices. The time-varying velocity fluctuations in the flow field are presented and discussed in detail. The velocity fluctuation contours are used to identify the regions of momentum transfer. The transient nature of the flow field is studied using the phase plot. A transition route from the periodic to chaotic regime though a quasi-periodic regime is established using time series analysis. The wake transitions are observed to be more sensitive towards heaving frequency than the heaving amplitude. [ABSTRACT FROM AUTHOR]

Benzodiazepines can make victims more docile, they are frequently used in drug-facilitated crimes, such as robberies and sexual assaults. Therefore, it is essential to develop techniques for determining whether these chemicals are present in relation with illegal activity is crucial. Therefore, to determine the presence of five benzodiazepines (alprazolam, clonazepam, diazepam, lorazepam, and oxazepam) in water, alcoholic beverages, and non-alcoholic beverages, a simple and direct, miniaturized, and effective vortex assisted ultrasound based microextraction using solidification of floating organic droplets (VAUS-ME-SFO) in combination with LC-MS/MS was developed. 1-Undecanol and acetonitrile, respectively, served as the extractant and disperser solvents. Many other parameters affect the efficiency of the developed analytical procedure VAUS-ME-SFO/LC-MS/MS. These parameters were optimized using Plackett Burman Design and Central Composite Design to obtain reliable results. The optimum conditions for the extraction were: 10.0 mL of sample; 180 μL acetonitrile, as a dispersive solvent; 200 μL of 1-undecanol, as an extraction solvent; pH 7; 105 s of vortex agitation; 120 s of ultrasonication application and 3 min of centrifugation at 7000 rpm. The benzodiazepines were separated by a chromatographic separation technique carried out by a UPLC system consisting of a binary mobile phase. The solvent system comprises of 0.1% Formic acid in Milli-Q (Solvent A) and 0.1% Formic acid in ACN (Solvent B) with a gradient flow of 3.5 min total analysis time. Under the optimized conditions, the calibration curve was studied in the range of 0.124–7.810 ng mL−1. The regression correlation coefficient (R2) value of all targeted analytes ranges from 0.993 to 0.999. The LOD and LOQ of VAUS-ME-SFO methods using LC-MS/MS analysis range from 0.316 to 0.968 ng mL−1 and 1.055–3.277 ng mL−1 respectively. The repeatability within a day varied from 0.6 to 3.5%, and the reproducibility across days varied from 2.2 to 6.3%. The recoveries ranges for water, alcoholic and non-alcoholic beverages from 70.77 to 114.53%, 63.20–102.21% and 66.23–113.28% respectively. Further, the degradation kinetics was studied to establish the half-life of each targeted analyte in the matrix undertaken in the study. The water samples were classified based on their BDZs residues. This implies that the more health care and anthropogenic activity, the more the BDZs residue will be in water samples. [Display omitted] • Using a statistical tool for optimization, a simple and précised extraction and analysis approach for the simultaneous analysis of benzodiazepine residue in drainage water samples. • The Plackett Burman Design (PBD) and Central Composite Design (CCD) were used as statistical tools for optimization and obtaining more reliable analytical results. • A degradation kinetics study is performed to assess the half-live and rate constant of benzodiazepines in water, alcoholic and non-alcoholic beverages. [ABSTRACT FROM AUTHOR]

The essential oil of Pelargonium graveolens (rose-scented geranium), an important aromatic plant, comprising mainly mono- and sesqui-terpenes, has applications in food and cosmetic industries. This study reports the characterization of isoprenyl disphosphate synthases (IDSs) involved in P. graveolens terpene biosynthesis. The six identified PgIDSs belonged to different classes of IDSs, comprising homomeric geranyl diphosphate synthases (GPPSs; PgGPPS1 and PgGPPS2), the large subunit of heteromeric GPPS or geranylgeranyl diphosphate synthases (GGPPSs; PgGGPPS), the small subunit of heteromeric GPPS (PgGPPS.SSUI and PgGPPS.SSUII), and farnesyl diphosphate synthases (FPPS; PgFPPS).All IDSs exhibited maximal expression in glandular trichomes (GTs), the site of aroma formation, and their expression except PgGPPS.SSUII was induced upon treatment with MeJA. Functional characterization of recombinant proteins revealed that PgGPPS1, PgGGPPS and PgFPPS were active enzymes producing GPP, GGPP/GPP, and FPP respectively, whereas both PgGPPS.SSUs and PgGPPS2 were inactive. Co-expression of PgGGPPS (that exhibited bifunctional G(G)PPS activity) with PgGPPS.SSUs in bacterial expression system showed lack of interaction between the two proteins, however, PgGGPPS interacted with a phylogenetically distant Antirrhinum majus GPPS.SSU. Further, transient expression of AmGPPS.SSU in P. graveolens leaf led to a significant increase in monoterpene levels. These findings provide insight into the types of IDSs and their role in providing precursors for different terpenoid components of P. graveolens essential oil. • Six IDSs that are highly expressed in glandular trichomes of P. graveolens were functionally characterized. • Results revealed geranium has a homomeric GPPS, a bifunctional G(G)PPS, and a FPPS involved in terpenoid precursor formation. • Enzyme kinetics indicated that both homomeric and bifunctional G(G)PPS provide precursors for monoterpene biosynthesis. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) exposure to the animals including humans is reported as nephrotoxic compounds i.e. , disturbing redox status (increase oxidative stress), mitochondrial dysfunction, renal cell death and altered transporters in the renal system. Hsp27 (a small heat shock protein) has been shown as one of the modulators in the renal dysfunction and increased against the Cd induced toxicity. However, no studies are reported on the genetic modulation of stress protein against the Cd-induced nephrotoxicity. The current study aimed to examine the protective role of hsp27 overexpression against the Cd-induced nephrotoxicity using Drosophila melanogaster as an animal model. D. melanogaster renal system includes nephrocytes and Malpighian tubules (MTs) that show the functional similarity with mammalian kidney nephron. Overexpression of the hsp27 was found to reduce the Cd induced oxidative stress, rescue cell death in MTs of Cd exposed D. melanogaster larvae. The rescued GSH level, NADPH level and glucose 6 phosphate dehydrogenase (G6PD) activity were also observed in the MTs of the Cd exposed organism. Function (efflux activity and fluid secretion rate) of the MTs was restored in Cd exposed hsp27 overexpressed larvae. Further, results were confirmed by restored brush border microvilli density and reduced uric acid level. Tissue specific knockdown of hsp27 developed Cd like phenotypes in MTs and the phenotypes enhanced in Cd exposed condition. The present study clearly shows the role of hsp27 overexpression in restoration of the MTs function and protection against the Cd induced renal toxicity. [Display omitted] • This study first time report nephroprotective role of hsp27 in Cd induce renal toxicity in MTs of the D. melanogaster larvae. • This study first time report nephroprotective role of hsp27 in Cd induce renal toxicity in MTs of the D. melanogaster larvae. • hsp27 overexpression restores MMP, ATP level and microvilli brush border density in MTs of Cd exposed D. melanogaster larvae. • hsp27 knockdown negatively alter MTs functions in D. melanogaster larvae and more severely affect after the Cd exposure. [ABSTRACT FROM AUTHOR]

β-triketone herbicides have been efficiently employed as an alternate to atrazine. Triketones are 4-hydroxyphenylpyruvate dioxygenase (HPPD) enzyme inhibitors and exposure is reported to cause significant increase in plasma tyrosine levels. In this study, we have employed a non-target organism Caenorhabditis elegans to determine the impact of β-triketone exposures at recommended field doses (RfD). Our results indicate sulcotrione and mesotrione, negatively influence the survival, behavior, and reproduction of the organism at RfD. Additionally, we have traced the parallels regarding the impact of triketones on the tyrosine metabolism pathway, in C. elegans to those in mammalian models, wherein the expression of the tyrosine metabolism pathway genes are altered, directly influencing tyrosine catabolism leading to significant tyrosine accumulation in exposed organism. Further, we investigated the impact of sulcotrione and mesotrione exposure on fat deposition (triglyceride levels, Oil-Red-O staining and lipidomics) and the fatty acid metabolism pathway. In the exposed worms, the expression of enlongases and fatty acid desaturases were up-regulated along with an increase in the levels of triglycerides. Thus, the data indicates a positive association of β-triketone exposure to mis-regulation of the fatty acid metabolism pathway genes leading to fat accumulation in worms. Therefore, β-triketone might be a potential obesogen. [Display omitted] • β-triketone significantly impacts behavior, and reproduction in C. elegans. • β-triketone exposure causes tyrosine and triglyceride accumulation in C. elegans. • Up-regulation of desaturases and elongases leads to fat deposition in exposed worms. [ABSTRACT FROM AUTHOR]

In the present study, effect of exposure of bisphenol A (BPA) and combined exposure of BPA + HSD has been investigated on the glucose homeostasis and associated renal complications in Drosophila. Exposure of 1.0 mM BPA alone induced type 2 diabetes like condition (T2D) in adult male D. melanogaster via oxidative stress. Elevated TGF-β signaling was evident by increased expression of baboon (babo) in BPA exposed organism that stimulated the modulation of extracellular matrix (ECM) component collagen IV resulting in the fibrosis of the Malpighian tubules (MTs). Combined exposure of BPA + HSD (high sucrose diet) resulted in the increased magnitude of T2D and MTs dysfunction parameters. Taken together, the study illustrates that BPA has diabetogenic potential in exposed Drosophila that caused adverse effects on their MTs and combined exposure with BPA and HSD could aggravate the renal tubular dysfunction. The study further suggests the use of Drosophila model to study the environmental chemicals induced diabetes mediated renal dysfunction. [Display omitted] • Bisphenol A (BPA) induces type 2 diabetes (T2D) like condition in Drosophila. • BPA induced oxidative stress results in fibrosis of Malpighian tubules (MTs). • Fibrosis in the MTs results in the structural deformities in them. • Structural deformities result in reduced function of MTs and shortened life span of Drosophila. • BPA + high sucrose diet (HSD) further increased the magnitude of T2D and MTs dysfunction parameters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pesticides and phthalates analysis in breakfast cereal samples. • QuEChERS protocol coupled to GC–MS/MS. • Method validation with uncertainty determination. • Identification of compounds involved in flavored and unflavored cereals using multivariate approach. • Increased concentration of pesticides in flavored cereals. Pesticides and phthalates are toxic chemical compounds which could be present in our food items through their different usage. Some of these toxic analytes are present in traces and always a challenge to quantify for analytical chemist especially from complex food matrices. A simple, sensitive, fast and robust QuEChERS based method was developed, optimized and validated. The method showed good linearity in the range of 0.30–50.00 ng g−1 with (r2) ≥ 0.9855. The quantification limit was in the range of 0.0983–0.8934 ng g−1 with recovery and precision in the range of 71.1–112.5% and RSD < 7.9% for all the analytes. The combined and expanded uncertainty was also determined showing strong analytical significance of the method with negligible matrix interferences. The developed method was successfully used for the analysis of 12 packaged cereal samples (flavoured = 7 & unflavoured = 5). Partial least square discrimination analysis (PLS–DA) of Multivariate approach was used to find differences in profile of pesticides and phthalates between the flavoured and unflavoured cereal samples. We obtained three pesticides (S-BioAllethrin, Dieldrin, Chlorfenapyr) as most important discriminatory compounds for the two groups after comparing fold change (FC) and variable importance in projection (VIP) analysis. Univariate analysis of 8 pesticides obtained from FC analysis showed increased concentration in flavoured group than the unflavoured cereals. The proposed work will be of immense use for routine analysis of these toxic compounds to deal with food fraud and uncover associated risk to the consumer. [ABSTRACT FROM AUTHOR]

• Biomarkers associated with lipid peroxidation, oxidative stress and kidney injury. • Use of validated DLLME method for biomarker analysis. • Analysis of 200 human urine samples of kitchen workers at high risk of PAHs exposure. • The developed method will be of immense use in clinical as well as routine analysis. Occupational exposure of Polyaromatic Hydrocarbons can lead to lipid peroxidation, oxidative stress and kidney function abnormalities. The biological marker compounds associated with these diseases and disorders are present in traces in biological fluids and their quantitative analysis can lead to many clinical applications. Hence, we developed 'Ultrasound assisted dispersive liquid–liquid microextraction' for the simultaneous analysis of 6 marker compounds using liquid chromatography mass spectrometry. The developed method is simple to use, rapid and very precise techniques for analyzing biological marker compounds associated with oxidative stress and kidney injury. The factors affecting the extraction efficiency have been optimized using design of experiment. Under the optimized conditions, the proposed method has been validated and the results showed linearity in the range 1–100 ng mL−1 with coefficient of determination (R2) ≥ 0.974–0.989 for all the analytes. The limit of detection and limit of quantification were in the range of 0.002–0.575 ng mL−1 and 0.006–1.898 ng mL−1 respectively with recovery (%) in the range of 94–116 % for all the analytes. The proposed method showed high reproducibility having intra-day and inter-day precision less than 3.21% and 7.31% respectively. We used our validated method to study the effect of PAHs exposure on human, where we analyzed 200 human urine samples obtained from mega kitchen workers. The results suggested that most of the marker compounds were up regulated in the exposed workers than the control one. [ABSTRACT FROM AUTHOR]