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This study investigated the flow around river's floodplain single groynes. Two different compound channels with one and two symmetrical floodplains having widths of 1-and 2-times of the main channel width, respectively, were used. Both impermeable and permeable groynes with three different relative lengths (relative to the floodplain width) and having three different permeability values of 40, 60, and 80% were investigated. The 3D flow velocities were measured in the horizontal plane at 0.25 and 0.5 of floodplain water depth (hf), and in the vertical plane at the main channel's centerline. Therefore, the flow velocities in the longitudinal, lateral, and vertical directions, and the flow water surfaces were measured and analyzed. The results showed that, as the groyne permeability increased up to 60%, a reduction of up to 30% to the maximum velocity and 22 % to the tip velocity were observed. The permeable groyne length had limited influence on the flow structure. Both the groyne permeability and the length ratio had significant effects on the floodplain water depth. The scouring and the deposition activities resulting from impermeable groynes can be avoided, should the groyne length be kept below half of the floodplain width.

Herein, a simple and accurate spectrophotometric method was developed to detect gatifloxacin (HGAT) in a pure and ophthalmic formulation. The method depends on complexation of HGAT with Co (II), Ni (II) and La(III) ions in ethanol medium at room temperature. The experimental conditions have been investigated to reach optimum conditions for HGAT-metal ions interaction, including detection of a suitable wavelength, medium pH, reaction time and reactants concentration. Moreover, the composition of these complexes in addition to their stability constants were also investigated and the result indicated that the molar ratio of HGAT: Metal ion is 1:1 for Ni (II) and La(III) ions and 1:2 for Co (II) ion. Beer's law plots were obeyed in the concentration ranges 18.77–150.16, 18.77–131.39 and 18.77–112.62 (μg mL −1 ) for Co(II), Ni(II) and La(III) ions interaction, respectively. The apparent molar absorptivity, Sandell's sensitivity, standard deviation, detection and quantification limits were calculated. The proposed method was successfully applied for the determination of HGAT in the bulk and ophthalmic formulation. The obtained results were compared statistically with other published methods and the results were in good agreement with those obtained by reported methods.

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Nutraceutical cranberry powder extract (CBPE) has distinct polyphenols inhibiting colon cancer growth and proliferation. However, its oral therapeutic efficacy is hindered because of its low permeability. This study aims to formulate chitosan surface-modified PLGA nanoparticles (CS-PLGA NPs) for encapsulating CBPE and modulating its release rate, permeation, cell targeting, and, therefore, its cytotoxicity. A full 23 factorial design is employed to scrutinize the effect of lactide/glycolide ratio, PLGA weight, and stabilizer concentrations on entrapment efficiency percentage (EE%), particle size (PS), polydispersity index (PDI), and zeta potential (ZP). The optimum formula (F4) shows spherical particles with a relatively high EE% (72.30 ± 2.86%), an appropriate size of 370.10 ± 10.31 nm, PDI; 0.398 ± 0.001, and ZP; −5.40 ± 0.21 mV. Alongside the ATR-FTIR outcomes, the chitosan surface-modified formula (CS-F4) demonstrates a significant increase in particle size (417.67 ± 6.77 nm) and a shift from negative to positive zeta potential (+21.63 ± 2.46 mV), confirming the efficiency of surface modification with chitosan. The intestinal permeability of F4 and CS-F4 is significantly increased by 2.19- and 3.10-fold, respectively, compared to the CBPE solution, with the permeability coefficient (Papp) being 2.05 × 10−4 cm/min and 2.91 × 10−4 cm/min, for F4 and CS-F4, respectively, compared to the CBPE solution, 9.36 × 10−5 cm/min. Moreover, CS-F4 evidences significant caspase-3 protein level expression stimulation and significant inhibition of vascular endothelial growth factor (VEGF) and signal transducer and activator of transcription-3 (STAT-3) protein expression levels, confirming the superiority of CS-F4 for targeting HT-29 cells. Briefly, CS-PLGA NPs could be regarded as a prosperous delivery system of CBPE with enhanced permeation, cell targeting, and antitumor efficacy.

Given the growing interest in river restoration and natural river improvement, groins are recommended as an essential hydraulic component for creating riparian habitats and controlling local flow. The optimum design of groins for environmental purposes is still not defined despite its long history of improving river flow dynamics. The primary goal of this paper is to determine the influence of hybrid groins' orientation angle and geometry on both the flow velocity and structure to enhance fish habitat. This study investigates six models of unsubmerged hybrid L-shape groins installed in a straight channel with a deformed bed. The hybrid L-shape groins consist of two parts, an impermeable part that objected to the flow, and a permeable one (piles rows) arranged in the flow direction. The influences of groin's both contraction/length ratio and orientation angle on the flow velocity and structure are studied. The contraction ratio represents the impermeable groin length relative to channel width (W/B), while the orientation angle (θ) is the groin inclination angle in the up/downstream direction. Groin models with 25% contraction ratio and up/downstream orientation angle (θ) of 45°, 60°, and 90° were used. Groin with an orientation angle of 45° toward downstream has introduced the highest reduction on the flow velocities. Also, groin with θ=90° downstream introduced low velocities, but these velocities still more than the reduction of 45° case. The area of the dead zone -the zone of low velocities-in the case of θ=45° is about 70 % more than that of θ=90°.

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