Preparation of Sensitivity Test Antibiotic Discs Using Some Nanomaterials to Detect Resistance of Pseudomonas Aergenosa to Some Antibiotics

This study was conducted to synthesize bentonite nanoparticles and load them on different antibiotics to increase the effectiveness of the antibiotics or treat the resistance of Pseudomonas aeruginosa to some types of antibiotics in the laboratory. The biosynthesized bentonite nanoparticles were characterized by spectrophotometry and scanning electron microscopy. Their antibacterial activity against Pseudomonas aeruginosa was determined by the (muller-hinton) method of diffusion in plates compared with antibiotics using different concentrations of each ranging from 12.5-200 µg/ml. The results of this study showed that it is possible to synthesize bentonite nanoparticles in an easy and environmentally friendly manner, and the maximum absorption spectra of these nanoparticles were at 420 and 430 nm using a spectrophotometer. The scanning electron microscope analysis also showed that the average diameter of these particles was 26 nanometers, in addition to their high activity against bacteria.

Effect of Metallisation of Basalt Fabric on Its Surface Resistivity

The main aim of the research was to carry out the surface modification of basalt fabric in order to improve selected thermal properties of the material, i.e., resistance to contact and radiant heat, to apply it in a hot work environment. Attention was focused on checking whether the metal coating deposited does not cause too high conductivity, which is dangerous to human health. The process of magnetron sputtering with the use of chromium and aluminum of various thickness values was applied to basalt fabrics. Based on scanning electron microscope analysis, it was found that none of the aluminum or chromium coatings covered 100% of the basalt fabric surface. Results of the surface resistance analysis of four out of the six samples of basalt fabrics tested indicate that they belong to anti-static materials. The metallic coatings obtained can potentially be used to improve the thermal properties of basalt fabric mentioned.

Daturaquids at Pinwheel Cave, California, provide unambiguous confirmation of the ingestion of hallucinogens at a rock art site

While debates have raged over the relationship between trance and rock art, unambiguous evidence of the consumption of hallucinogens has not been reported from any rock art site in the world. A painting possibly representing the flowers ofDaturaon the ceiling of a Californian rock art site called Pinwheel Cave was discovered alongside fibrous quids in the same ceiling. Even though Native Californians are historically documented to have usedDaturato enter trance states, little evidence exists to associate it with rock art. A multianalytical approach to the rock art, the quids, and the archaeological context of this site was undertaken. Liquid chromatography−mass spectrometry (LC-MS) results found hallucinogenic alkaloids scopolamine and atropine in the quids, while scanning electron microscope analysis confirms most to beDatura wrightii. Three-dimensional (3D) analyses of the quids indicate the quids were likely masticated and thus consumed in the cave under the paintings. Archaeological evidence and chronological dating shows the site was well utilized as a temporary residence for a range of activities from Late Prehistory through Colonial Periods. This indicates thatDaturawas ingested in the cave and that the rock painting represents the plant itself, serving to codify communal rituals involving this powerful entheogen. These results confirm the use of hallucinogens at a rock art site while calling into question previous assumptions concerning trance and rock art imagery.

Susceptibility Assessment of Multidrug Resistant Bacteria to Natural Products

Objective: The aim of this study was to examine the effect of some natural compounds against multidrug-resistant bacteria. Methods: Forty-three bacterial strains were collected. Disc diffusion and minimum inhibitory concentration (MIC) tests were carried out for natural compounds including quercetin, Acacia nilotica, Syzygium aromaticum, and Holothuria atra. Scanning electron microscope analysis and bacterial DNA apoptosis assays were performed. Results: Staphylococcus aureus strains were resistant to imipenim, ampicillin, and penicillin. Most Escherichia coli strains were resistant to amoxicillin, clavulanat, and ampicillin. Finally, tigecycline was effective with Klebsiella pneumoniae and was resistant to all antibiotics. Only S aromaticum had an antibacterial effect on K pneumoniae. Most S aureus strains were sensitive to S aromaticum, A nilotica, and quercetin. All examined natural extracts had no effect on E coli. Holothuria atra had no effect on any of the strains tested. Minimum inhibitory concentration and minimum bactericidal concentration values for examined plants against S aureus were 6.25 to 12, 1.6 to 3.2, and 9.12 to 18.24 mg/mL, respectively. Syzygium aromaticum was active against K pneumoniae with an MIC of 12.5 mg/mL. Scanning electron microscope analysis performed after 24 and 48 hours of incubation showed bacterial strains with distorted shapes and severe cell wall damage. Syzygium aromaticum, quercetin, and A nilotica showed clear fragmentations of S aureus DNA. Conclusions: Current findings confirmed the beneficial effect of using natural products such as clove (S aromaticum), quercetin, and A nilotica as a promising therapy to overcome multidrug resistant bacteria.

Characterisation of Electrode Drying Effect on the Tungsten Carbide Hardfacing Microstructure

This study addresses characterization of ED (electrode drying) effect on WC hardfacing welding microstructure. Medium carbon steel blade which used as CD (continuous digester) blade to mix up sulphuric acid together with ilmenite ore in a digester tank as a major part of production. Microstructure of WC hardfacing, elemental composition alongside hardness analyses are executed to investigate the effect of ED (electrode drying). The ED (electrode drying) effect on microstructure and hardness values of WC hardafcing coating are characterized by SEM (scanning electron microscope) analysis and micro-Vickers hardness tester correspondingly. Results revealed that ED (electrode drying) effect less significant in the larger carbides at overall coating zone. However, the absence of ED (electrode drying) led to distribution of uniform smaller carbide in non-carbide zone. The uniform carbide distribution increases the hardness of the WC hardfacing coating.

Failure Analysis of Clamp Crack on TA Equipment in Converter Station

Through macro inspection, chemical composition analysis, hardness test, tensile performance test, microstructure inspection and scanning electron microscope analysis, the causes of clamp crack on TA equipment in the 500kV AC filter field of the ± 800kV converter station were analyzed. The results show that improper selection of the manufacturing process of the equipment clamps will cause more micro-defects inside it, leading to poor mechanical properties and excessive internal stress, which are the main causes of cracking. Corresponding measures are put forward to improve the manufacturing quality of equipment clamps, which can avoid similar failures from happening again.