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This paper aims to investigate a mathematical model with numerical simulation for bacterial growth in the heart valve.

For antibacterial activities and antibodies properties, nanoparticles have been used. As antibiotics are commonly thought to be homogeneously dispersed through the blood, therefore, non-Newtonian fluid of Casson micropolar blood flow in the heart valve for two dimensional with variable properties is used. The heat transfer with induced magnetic field translational attraction under the influence of slip is considered for the resemblance of the heart valve prosthesis. The numeral results have been obtained by using the Chebyshev pseudospectral method.

It is proven that vascular resistance decreases for increasing blood velocity. It is noted that when the magnetic field will be induced from the heart valve prosthesis then it may cause a decrease in vascular resistance. The unbounded molecules and antibiotic concentration that are able to penetrate the bacteria are increased by increasing values of vascular resistance. The bacterial growth density cultivates for upswing values of magnetic permeability and magnetic parameters.

To the best of the authors’ knowledge, this is the first study to investigate a mathematical model with numerical simulation for bacterial growth in the heart valve.

Bacterial action often constitutes a major cause of corrosion in petroleum refineries and similar plant. The problem occurs in three major areas: in underground structures, in cooling water systems and in storage facilities for both crude and refined petroleum products. What are the factors upon which bacterial corrosion depends and what are the remedies?

The purpose of this research is to assess the removal of oil spills from the seawater surface as well as the antibacterial activity of ZnFe₂O₄-cetyltrimethylammonium bromide (CTAB, cationic surfactant) magnetic nanoparticles (ZFO-CTAB MNPs).

A CTAB-assisted sol–gel method was used to synthesize ZFO-CTAB MNPs. X-ray powder diffraction and Fourier transform infrared spectroscopy were used for ZFO-CTAB MNPs characterization. Also, the magnetic force and apparent density of ZFO-CTAB MNPs were determined. The oil spill cleanup was investigated by using the gravimetric oil removal (GOR) technique, which used ZFO-CTAB MNPs as oil absorbent material and four oil samples (crude, diesel, gasoline and used oil) as oil spill models. The antibacterial activity of ZFO-CTAB MNPs against Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi) was investigated by using the optical density method.

The results revealed that, when the amount of ZFO-CTAB was 0.01 g, gasoline oil had the highest GOR (51.80 ± 0.88 g/g) and crude oil had the lowest (11.29 ± 0.82 g/g). Furthermore, for Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa, ZFO-CTAB MNPs inhibited bacterial growth with a higher percentage (94.24%–95.63%).

The applications of ZFO-CTAB MNPs in the cleanup of oil spills from aqueous solutions, as well as their antibacterial activity. The results showed that ZFO-CTAB MNPs are a promising material for removing oil spills from bodies of water as well as an antibacterial agent against Gram-negative bacterial strains.

The study aims to determine an efficiency of external magnetic field on the bacteria surrounded by thousands of magnetic magnetite nanoparticles. The interstitial nanoliquid in which an artificial bacteria swims in biological cell is utilized with variable thermal conductivity. Two dimensions unsteady motion of second grade fluid are considered. The stretching wall is taken as a curved surface pattern.

The mathematical results have been obtained by Chebyshev pseudospectral method.

The impact of the various governing parameters is described by numerical tables and diagrams. It is proven that the pure blood velocity curves are higher when compared with the magnetite/blood. It is demonstrated from clinical disease that dangerous tumors show diminished blood flow. This study concludes that the blood velocity profile increases by increasing the values of fluid parameters. This implies that the medication conveyance therapy lessens the tumor volume and helps in annihilating malignancy cells. The blood temperature distribution raises as the magnetite nanoparticles concentration increases. Consequently, the physical properties of the blood can be enhanced by immersing the magnetite nanoparticles. Further, the present outcomes cleared the thermal conductivity as, a variable function of the temperature, has an important role to enhance the heat transfer rate.

To the best of authors’ knowledge, this study is reported for the first time.

The main purpose of this study resides essentially in the development of a new tool to quantify the biomass in the bioreactor operating under steady state conditions.

Modeling is the most relevant tool for understanding the functioning of some complex processes such as biological wastewater treatment. A steady state model equation of activated sludge model 1 (ASM1) was developed, especially for autotrophic biomass (XBA) and for oxygen uptake rate (OUR). Furthermore, a respirometric measurement, under steady state and endogenous conditions, was used as a new tool for quantifying the viable biomass concentration in the bioreactor.

The developed steady state equations simplified the sensitivity analysis and allowed the autotrophic biomass (XBA) quantification. Indeed, the XBA concentration was approximately 212 mg COD/L and 454 mgCOD/L for SRT, equal to 20 and 40 d, respectively. Under the steady state condition, monitoring of endogenous OUR permitted biomass quantification in the bioreactor. Comparing XBA obtained by the steady state equation and respirometric tool indicated a percentage deviation of about 3 to 13%. Modeling bioreactor using GPS-X showed an excellent agreement between simulation and experimental measurements concerning the XBA evolution.

These results confirmed the importance of respirometric measurements as a simple and available tool for quantifying biomass.

Several factors may play critical roles in alterations to product quality during storage of hog plum juice. This study aims to evaluate variations to physicochemical, antioxidant, anti-nutritional properties and microbial stability of hog plum juice during storage.

Juice was produced from hog plum fruits and stored for eight weeks at refrigerated and ambient conditions. Physicochemical, antioxidant properties, antinutritional factors and microbial properties of juices were determined using standard procedures

Degradation of ascorbic acid was higher in juices stored at ambient conditions (64.4%) compared to those stored by refrigeration (44.4%). Trends were similar for total phenolic, total flavonoid and total carotenoid contents. Total phenolic, total carotenoid and lycopene contents of fresh juice were 3.9 mg GAE/mL, 4.0 mg/mL and 1.3 mg/mL, which were not significantly different (at p = 0.08, 0.07 and 0.08, respectively) from the values at two weeks of storage at refrigerated conditions (3.9 mg GAE/mL, 3.9 mg/mL and 1.3 mg/mL). A sharp decrease of more than 40% (p = 0.02) in lycopene was recorded after four weeks, irrespective of storage temperature. Pasteurized hog plum juice showed no microbial growth until after four weeks of refrigerated storage when 1 CFU/mL each of bacterial and fungal growth were recorded. The juices, however, showed higher susceptibility to fungal growth as storage period increased.

Other variables not considered in this study such as nature of packaging materials may have significantly contributed to the observed data set. Further studies may, therefore, widen the scope of discussion to evaluate the associated relationship of these variables. Hog plum juice retained a considerable amount of bioactive components during refrigerated storage, which makes it a viable nutraceutical drink with industrial potentials and possible positive health implications for consumers.

This study provides new information that support the possible classification and use of hog plum juice as a safe functional beverage for human consumption.

Although the effect of storage temperature was significant in most of the properties studied, storage duration seems to have a greater influence on the stability of quality parameters during the storage of hog plum juice.

The purpose of this paper is to evaluate the prevalence and antibiograms of bacteria isolated from various fresh fruit juices at a local market in Faisalabad.

Fresh fruit juice samples (n=125) were randomly collected using aseptic technique. Each sample (10 mL) was serially diluted with 90 mL of sterile peptone water, from 1×10⁻¹ to 1×10⁻⁵. Each dilution was then used to inoculate nutrient agar by surface spread plating. Aerobic colony counts (ACCs) were determined by colony counting. The isolates were sub-cultured on blood and MacConkey agar. Preliminary identification was achieved on the basis of colony morphology and culture characteristic, and confirmed by API® 20E, 20NE, and API® Staph testing. Antimicrobial susceptibility testing was carried out using the Kirby-Bauer disk diffusion assay, per CLSI 2015 guidelines.

The mean ACC ranged from 2.0×10⁶ CFU/mL to 4.93×10⁶ CFU/mL, with the highest ACC determined for orange juice. Overall, 153 polymicrobial were identified in 125 samples; 103 of these were Gram-negative rods (GNR) and 28 were Gram-positive cocci (GPC). Escherichia coli (n=38), Klebsiella pneumoniae (n=32) and Pseudomonas aeruginosa (n=24) were the predominant GNR; Staphylococcus aureus (n=28) was the predominant GPC. Antibiogram analysis revealed that all GNR were resistant to ampicillin. However, most E. coli isolates were resistant to ceftazidime (72.4 percent of isolates), and ceftriaxone and cefepime (68.9 percent), while most K. pneumoniae isolates were resistant to cefepime (72 percent) and ceftriaxone (64 percent). All S. aureus isolates were resistant to penicillin, while most (64 percent) were resistant to piperacillin; the most effective drugs against bacteria were vancomycin and imipenem.

The findings suggest that the local government regulatory food and public health authorities should take immediate emergency measures. Appropriate surveillance studies and periodic monitoring of food items should be regularly performed to safeguard public health.

The current study revealed the prevalence of multidrug-resistant bacteria in freshly prepared fruit juices sold by local street vendors.

Microbiologically induced corrosion of copper intrauterine devices “TCu380A” and “Nova T” by Enterobacter sp. in a synthetic intrauterine medium was investigated. The corrosion behaviour was evaluated applying cyclic voltammetry and Tafel Polarization. The surface morphology was determined using scanning electron microscopy, the corrosion products were analyzed using energy dispersive X‐rays and the biofilm composition was examined by Fourier transform infrared spectroscopy with an attenuated total reflectance device.

The purpose of this paper was to synthesize novel antibacterial reactive dyes for dyeing cotton fabrics.

Four synthetic novel antibacterial reactive dyes based on sulfonamide (D1-D4) have been synthesized by the coupling reaction of sulfonamide diazonium salt with sulfonamido-cyanurated 7-amino-4-hydroxynaphthalene-2-sulfonic acid “j-acid”. The chemical structure of the synthesized dyes was secured by their spectral data [infra red (IR) and proton Nuclear magnetic Resonance (1HNMR)].

The prepared reactive dyes (D1-D4) were applied to cotton fabrics. Optimum conditions of the dying samples at sodium sulfate 100 g/l, liquor ratio (L.R.) 1:10, sodium carbonate 20 g/l at 80°C (D1, D2 and D4), 60°C (D3 for 60 min) were investigated. The fastness properties toward washing, perspiration, rubbing and light were evaluated. Dyed fabrics showed good light fastness property and good to very good washing and perspiration fastness properties according to the gray scale. Antimicrobial activities for synthesized dyes showed excellent activity against gram-negative organisms such as Pseudomonas aeruginosa and Proteus mirabilis faecalis, whereas very good activity against gram-positive organisms such as Staphylococcus aureus and Enterococcus faecalis with respect to the standard drugs ampicillin and chloramphenicol.

The principle advantages in this study were that the synthesis of novel synthesized dyes by introducing bisulfonamide-based moieties to increase the antimicrobial activity of the cellulose fabrics could be used as a medical textile, short reaction time and reaction procedure conducted in few steps, the work up is convenient and thus the starting material can be easily prepared.

A novel two series of self‐sequestering surfactants have been prepared by the reaction of itaconic acid, phthalic anhydride, citric acid with oxypropylated 1,4‐butane diol and oxypropylated 1,6‐hexane diol. The structure features of these surfactants have been confirmed by IR and ¹H NMR spectra. These surfactants exhibit excellent properties of self‐sequestering. Besides good surface active properties including surface tension, interfacial tension, low foaming, good wetting properties, good stability towards acidic and basic media, emulsifying power and dispresent properties, solubilization properties and good biodegradability, they possess autonomous sequestering ability without any help of additional sequestering agent.