Chemical Composition and Antioxidant,Antimicrobial, and Anti-Inflammatory Properties of Origanum compactum Benth Essential Oils from Two Regions: In Vitro and In Vivo Evidence and In Silico Molecular Investigations

The purposes of this investigatory study were to determine the chemical composition of the essential oils (EOs) of Origanum compactum from two Moroccan regions (Boulemane and Taounate), as well as the evaluation of their biological effects. Determining EOs’ chemical composition was performed by a gas chromatography–mass spectrophotometer (GC-MS). The antioxidant activity of EOs was evaluated using free radical scavenging ability (DPPH method), fluorescence recovery after photobleaching (FRAP), and lipid peroxidation inhibition assays. The anti-inflammatory effect was assessed in vitro using the 5-lipoxygenase (5-LOX) inhibition test and in vivo using the carrageenan-induced paw edema model. Finally, the antibacterial effect was evaluated against several strains using the disk-diffusion assay and the micro-dilution method. The chemical constituent of O. compactum EO (OCEO) from the Boulemane zone is dominated by carvacrol (45.80%), thymol (18.86%), and α-pinene (13.43%). However, OCEO from the Taounate zone is rich in 3-carene (19.56%), thymol (12.98%), and o-cymene (11.16%). OCEO from Taounate showed higher antioxidant activity than EO from Boulemane. Nevertheless, EO from Boulemane considerably inhibited 5-LOX (IC₅₀ = 0.68 ± 0.02 µg/mL) compared to EO from Taounate (IC₅₀ = 1.33 ± 0.01 µg/mL). A similar result was obtained for tyrosinase inhibition with Boulemane EO and Taounate EO, which gave IC_50s of 27.51 ± 0.03 μg/mL and 41.83 ± 0.01 μg/mL, respectively. The in vivo anti-inflammatory test showed promising effects; both EOs inhibit and reduce inflammation in mice. For antibacterial activity, both EOs were found to be significantly active against all strains tested in the disk-diffusion test, but O. compactum EO from the Boulemane region showed the highest activity. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) for O. compactum EO from the Boulemane region ranged from 0.06 to 0.25% (v/v) and from 0.15 to 0.21% (v/v) for O. compactum from the Taounate region. The MBC/MIC index revealed that both EOs exhibited remarkable bactericidal effects.     

Performance of hydrodynamic journal bearing under the combined influence of textured surface and journal misalignment: A numerical survey

A wisely chosen geometry of micro textures with the favorable relative motion of lubricated surfaces in contacts can enhance tribological characteristics. In this paper, a computational investigation related to the combined influence of bearing surface texturing and journal misalignment on the performances of hydrodynamic journal bearings is reported. To this end, a numerical analysis is performed to test three texture shapes: square “SQ”, cylindrical “CY”, and triangular “TR”, and shaft misalignment variation in angle and degree. The Reynolds equation of a thin viscous film is solved using a finite differences scheme and a mass conservation algorithm (JFO boundary conditions), taking into account the presence of textures on both full film and cavitation regions. Preliminary results are compared with benchmark data and are consistent with a positive enhancement in misaligned bearing performances (load carrying capacity and friction). The results suggest that the micro-step bearing mechanism is a key parameter, where the micro-pressure recovery action present in dimples located at the second angular part of the bearing (from 180° to 360°) can compensate for the loss on performances caused by shaft misalignment, while the micro-pressure drop effect at the full film region causes poor performances. Considering the right arrangement of textures on the contact surface, their contours geometries can have a significant impact on the performance of misaligned journal bearings, particularly at high eccentricity ratios, high misalignment degrees and when the misalignment angle α approaches to $0\mathrm{°}$ or $180\mathrm{°}$.     

Determination of Phenolic Compounds in Various Propolis Samples Collected from an African and an Asian Region and Their Impact on Antioxidant and Antibacterial Activities

The biological activities of propolis samples are the result of many bioactive compounds present in the propolis. The aim of the present study was to determine the various chemical compounds of some selected propolis samples collected from Palestine and Morocco by the High-Performance Liquid Chromatography–Photodiode Array Detection (HPLC-PDA) method, as well as the antioxidant and antibacterial activities of this bee product. The chemical analysis of propolis samples by HPLC-PDA shows the cinnamic acid content in the Palestinian sample is higher compared to that in Moroccan propolis. The results of antioxidant activity demonstrated an important free radical scavenging activity (2,2-Diphenyl-1-picrylhydrazyl (DPPH); 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and reducing power assays) with EC₅₀ values ranging between 0.02 ± 0.001 and 0.14 ± 0.01 mg/mL. Additionally, all tested propolis samples possessed a moderate antibacterial activity against bacterial strains. Notably, Minimum Inhibitory Concentrations (MICs) values ranged from 0.31 to 2.50 mg/mL for Gram-negative bacterial strains and from 0.09 to 0.125 mg/mL for Gram-positive bacterial strains. The S2 sample from Morocco and the S4 sample from Palestine had the highest content of polyphenol level. Thus, the strong antioxidant and antibacterial properties were apparently due to the high total phenolic and flavone/flavonol contents in the samples. As a conclusion, the activities of propolis samples collected from both countries are similar, while the cinnamic acid in the Palestinian samples was more than that of the Moroccan samples.     

New figuring model based on surface slope profile for grazing‐incidence reflective optics

Surface slope profile is widely used in the metrology of grazing‐incidence reflective optics instead of surface height profile. Nevertheless, the theoretical and experimental model currently used in deterministic optical figuring processes is based on surface height, not on surface slope. This means that the raw slope profile data from metrology need to be converted to height profile to perform the current height‐based figuring processes. The inevitable measurement noise in the raw slope data will introduce significant cumulative error in the resultant height profiles. As a consequence, this conversion will degrade the determinism of the figuring processes, and will have an impact on the ultimate surface figuring results. To overcome this problem, an innovative figuring model is proposed, which directly uses the raw slope profile data instead of the usual height data as input for the deterministic process. In this paper, first the influence of the measurement noise on the resultant height profile is analyzed, and then a new model is presented; finally a demonstration experiment is carried out using a one‐dimensional ion beam figuring process to demonstrate the validity of our approach.     

A damage identification technique for beam-like and truss structures based on FRF and Bat Algorithm

In this paper, a Structural Health Monitoring (SHM) technique for damage identification in beam-like and truss structures using Frequency Response Function (FRF) data coupled with optimization techniques is presented. Genetic Algorithm (GA) and Bat Algorithm (BA) are used to estimate the location and severity of damage. The damage in the structures is simulated by reduction in rigidity of specific members. Both optimization techniques are coupled with modelled structures using Finite Element Method (FEM). The approach is based on minimizing an objective function by comparing measured and calculated FRFs. The results show that better accuracy is obtained using BA than using GA in terms of precision and computational time. Furthermore, it is found that the proposed approach provides faster solution than other approaches in the literature.     

Automatic alignment of a Kirkpatrick-Baez active optic by use of a soft-x-ray Hartmann wavefront sensor

We present what we believe to be the first automatic alignment of a synchrotron beamline by the Hartmann technique. Experiments were performed, in the soft-x-ray range (E=3 keV, lambda=0.414 nm), by using a four-actuator Kirkpatrick-Baez (KB) active optic. A system imaging the KB focal spot and a soft-x-ray Hartmann wavefront sensor were used alternatively to control the KB optic. The beam corrected with the help of the imaging system was used to calibrate the wavefront sensor. With both closed loops, we focused the beam into a 6.8 microm x 9 microm FWHM focal spot.     

Recent developments in X-UV optics and X-UV diagnostics

Metrology of XUV beams (X-ray lasers, high-harmonic generation and VUV free-electron lasers) is of crucial importance for the development of applications. We have thus developed several new optical systems enabling us to measure the optical properties of XUV beams. By use of a Michelson interferometer working as a Fourier-transform spectrometer, the line shapes of different X-ray lasers have been measured with a very high accuracy (/10^-6). Achievement of the first XUV wavefront sensor has enabled us to measure the beam quality of laser-pumped as well as discharge-pumped X-ray lasers. A capillary discharge X-ray laser has demonstrated a very good wavefront allowing us to achieve an intensity as high as 3×10¹⁴ Wcm^-2 by focusing with a f=5 cm mirror. The sensor accuracy has been measured using a calibrated spherical wave generated by diffraction. The accuracy has been estimated to be as good as /120 at 13 nm. Commercial developments are underway. At Laboratoire dOptique Appliquée, we are setting up a new beamline based on high-harmonic generation in order to start the femtosecond, coherent XUV optic . PACS 07.85.Nc;32.70.Jz;41.50.+h;42.15.Dp;42.55.Vc;52.70.La     

Hartmann wave-front measurement at 13.4 nm with lambdaEUV/120 accuracy

We report, for the first time to our knowledge, experimental demonstration of wave-front analysis via the Hartmann technique in the extreme ultraviolet range. The reference wave front needed to calibrate the sensor was generated by spatially filtering a focused undulator beam with 1.7- and 0.6-microm-diameter pinholes. To fully characterize the sensor, accuracy and sensitivity measurements were performed. The incident beam's wavelength was varied from 7 to 25 nm. Measurements of accuracy better than lambdaEUV/120 (0.11 nm) were obtained at lambdaEUV = 13.4 nm. The aberrations introduced by an additional thin mirror, as well as wave front of the spatially unfiltered incident beam, were also measured.     

Quadriwave lateral shearing interferometry in an achromatic and continuously self-imaging regime for future x-ray phase imaging

We present in this Letter a type of quadriwave lateral shearing interferometer for x-ray phase imaging. This device is based on a phase chessboard, and we take advantage of the large spectrum of the source to produce interferograms with a propagation-invariant contrast. Such a grating has been created for hard x-ray interferometry and experimentally tested on a synchrotron beamline at Soleil.