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Herein, silver nanoparticles (Ag) embedded in polystyrene (PS) nanofiber composites have been prepared by an electrospinning technique using N, N-dimethylformamide (DMF) as a solvent and safe reducing agent. Electrospinning of polystyrene (PS) solutions is conducted using different electrospinning parameters such as polymer concentration in the electrospinning solution; solution feed rate, and electrical field strength. Then silver nanoparticles (AgNPs) were embedded into PS nanofibers to obtain an AgNPs-PS nanofiber composite as a powerful, cheap, and nontoxic bioactive material. PS nanofibers and AgNPs-PS nanofibers composite were characterized by using thermogravimetric analysis (TGA), X-ray diffraction, and scanning electron microscopy (SEM). Also, AgNPs were characterized by UV-vis spectroscopy, transmission electron microscopy (TEM), and EDX analysis. Results showed that PS nanofibers were obtained with concentrations ranging from 10–30 wt.% in DMF solvent. Also, an AgNPs-PS nanofiber composite has been produced from its solutions by using DMF at the optimum value. The prepared AgNPs have a 21–40 nm particle size and a semi-spherical shape. In addition, the antibacterial activity of AgNPs-PS nanofibers towards both Gram-positive and Gram-negative bacteria has been increased. Therefore, this nanocomposite can be used as a powerful bioactive material in biomedical fields.

The corrosion resistance of polyvinyl chloride (PVC) pipes immersed in tap water and different chemical solutions was investigated. Tests were performed at room temperature with the material exposed to 100% relative humidity and to different types of liquids such as tap water, sea water, solar, kerosene, lubricating oil, ethyl alcohol (95% C 2 H 5 OH), acetic acid (CH 3 COOH), 20% sodium hydroxide (NaOH), and benzene for exposure periods of 30, 60, and 90 days. Changes in weight, pH values, ultimate flexural strength, ultimate tensile strength, and Charpy impact resistance were measured over interval of testing times and the effects of the different corrosive environments on these parameters were assessed. The results indicated that the change in flexural strength, tensile strength, and ORDER REPRINTS Charpy impact resistance depends upon the period of exposure and the media.

Background: Blastocystis hominis (B. hominis) is a ubiquitous parasite that has spread worldwide and is commonly present in human stool specimens. It was hypothesized that infection with B. hominis plays a role in the pathogenesis of autoimmune diseases in humans. The aim of this study is to test this hypothesis by investigating patients with autoimmune diseases. Patients with various types of autoimmune diseases with gastrointestinal symptoms were enrolled in this study as cases (n = 72) along with nongastrointestinal symptom patients as controls (n = 58). All participants in this study were subjected to history taking and were investigated for B. hominis infection via wet-mount microscopic stool examinations, staining with trichrome stain, and molecular-based tests applied to their fecal samples. Blood samples were also tested for complete blood counts. B. hominis were identified with specific PCR more in cases (12/72; 16.6%) than in controls (3/58; 5.2%), with a significant difference (p < 0.05). Significant decreases in white blood cell counts were demonstrated in systemic lupus erythematosus (SLE) and ulcerative colitis (UC) patients infected with B. hominis when compared to patients with nongastrointestinal symptoms (p-value < 0.05).

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