Background: This research identified Streptococci spp. depending on culture, biochemistry, the VITEK technique, ability to produce biofilms, and antibiotic resistance. Aim: The goal of this study was to perform microbiological procedures to evaluate the qualitative qualities of mozzarella cheese against infective Streptococci using microbiological care. Methods: Sixty (60) mozzarella cheese samples were brought from diverse markets in Baghdad from October 2023 to December 2023 at the Zoonoses Research Unit and Veterinary Public Health Department, Veterinary Medicine College, University of Baghdad. Culture of samples on agar (MacConkey and blood) and aerobically incubated at 37°C for 48 hours. Gram staining purified colonies to notice Gram-positive cocci arranged in strings that were supposed to be Streptococcus species, and then sub cultured on nutrient agar for identification using the VITEK technique. The isolates were tested for their capacity to lyse human red blood cells by streaking blood agar and incubating at 37°C for 24 hours. Streptococcal isolates were streaked on a Congo-red medium. All isolates were inspected for antibiotic susceptibility using 15 common antibiotics via the disc diffusion method. Results: Isolates mozzarella cheese samples 8 (13.3%), these (eight) isolates include: (Streptococcus thoraltensis, Streptococcus sanguinis, Streptococcus cremoris, and Streptococcus alactolyticus. The susceptibility of S. thoraltensis, S. sanguinis, and S. alactolyticus was (26.6%), and S. cremoris (20%) to all antibiotics. Resistance of S. thoraltensis was (53%), S. sanguinis, S. alactolyticus were (66%), and S. cremoris was (73%) to all antibiotics. S. thoraltensis, S. cremoris, and S. alactolyticus were susceptible (75%) to Amikacin. S.sanguinis and S. cremoris were susceptible (50%) to Tigecycline. Streptococcus thoraltensis and S. alactolyticus were susceptible (50%) to Doxycycline. Streptococcus sanguinis and S. alactolyticus were susceptible (50%) to Ciprofloxacin. Streptococcus thoraltensis and S. sanguinis were susceptible (50%) to Azithromycin. Streptococcus sanguinis was susceptible (25%) to vancomycin. Streptococcus alactolyticus was susceptible (25%) to Streptomycin. Streptococcus thoraltensis was susceptible (25%) to Amoxicillin and Clavulanic acid. S. cremoris was susceptible (25%) to Penicillin. All isolates were 100% resistant to imipenem, lincomycin, meropenem, methicillin, and chloramphenicol. Conclusion: Analysis of mozzarella cheese samples identified four predominant Streptococcus species and their antibiotic activity.
The esterification of oleic acid with 2-ethylhexanol in presence of sulfuric acid as homogeneous catalyst was investigated in this work to produce 2-ethylhexyl oleate (biodiesel) by using semi batch reactive distillation. The effect of reaction temperature (100 to 130°C), 2-ethylhexanol:oleic acid molar ratio (1:1 to 1:3) and catalysts concentration (0.2 to 1wt%) were studied. Higher conversion of 97% was achieved with operating conditions of reaction temperature of 130°C, molar ratio of free fatty acid to alcohol of 1:2 and catalyst concentration of 1wt%. A simulation was adopted from basic principles of the reactive distillation using MATLAB to describe the process. Good agreement was achieved.
Photonic Crystal Fiber Interferometers (PCFIs) are widely used for sensing applications. This work presents the fabrication and the characterization of a relative humidity sensor based on a polymer-coated photonic crystal fiber that operates in a Mach- Zehnder Interferometer (MZI) transmission mode. The fabrication of the sensor involved splicing a short (1 cm) length of Photonic Crystal Fiber (PCF) between two single-mode fibers (SMF). It was then coated with a layer of agarose solution. Experimental results showed that a high humidity sensitivity of 29.37 pm/%RH was achieved within a measurement range of 27–95%RH. The sensor also showed good repeatability, small size, measurement accuracy and wide humidity range. The RH sensitivity o
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Numerical study has been conducted to investigate the thermal performance enhancement of flat plate solar water collector by integrating the solar collector with metal foam blocks.The flow is assumed to be steady, incompressible and two dimensional in an inclined channel. The channel is provided with eight foam blocks manufactured form copper. The Brinkman-Forchheimer extended Darcy model is utilized to simulate the flow in the porous medium and the Navier-Stokes equation in the fluid region. The energy equation is used with local thermal equilibrium (LTE) assumption to simulate the thermofield inside the porous medium. The current investigation covers a range of solar radiation intensity at 09:00 AM, 12:00 PM, and 04:00
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A true random TTL pulse generator was implemented and investigated for quantum key distribution systems. The random TTL signals are generated by low cost components available in the local markets. The TTL signals are obtained by using true random binary sequences based on registering photon arrival time difference registered in coincidence windows between two single – photon detectors. The true random TTL pulse generator performance was tested by using time to digital converters which gives accurate readings for photon arrival time. The proposed true random pulse TTL generator can be used in any quantum -key distribution system for random operation of the transmitters for these systems
Phase change materials are extensively studied for use in low-, mid-, and high-temperature applications due to their melting and solidification temperatures, latent heat, and thermophysical properties. This work aims to explore the energy stored, or released and their duration for the energy storage unit formed of a phase change material surrounding a tube within which a hot or cold, single or Two-Phase fluid flows, serving as a heat source or sink. The 3D axial transient thermal analysis of the energy storage unit is performed using the finite element method via a MATLAB-developed computer program. The effects of single- or Two-Phase fluid flow on temperature distribution, solidification, melting duration, and energy stored within phase ch
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A mathematical method with a new algorithm with the aid of Matlab language is proposed to compute the linear equivalence (or the recursion length) of the pseudo-random key-stream periodic sequences using Fourier transform. The proposed method enables the computation of the linear equivalence to determine the degree of the complexity of any binary or real periodic sequences produced from linear or nonlinear key-stream generators. The procedure can be used with comparatively greater computational ease and efficiency. The results of this algorithm are compared with Berlekamp-Massey (BM) method and good results are obtained where the results of the Fourier transform are more accurate than those of (BM) method for computing the linear equivalenc
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Extract from cell culture of medicinal plant like Nigella sativa have been assessed for its cytotoxic properties. Thymol is likely responsible for the theraputic effects of Nigella sativa leaf callus extract. In this short study the inhibitory effect of Nigella sativa leaf callus extract (Thymol) has been studied on Human Lorgnx Epidrmoid Carcinoma (Hep-2) cell line during different exposure period of time (24, 48 and 72 hrs.) using different concentration of the extract (1000, 500, 400, 300, 200 and 100 µg/ml). The optical density of the Hep-2 cells has been readed on 492 nm wave length. Thymol –induced cytotoxicity was (500 µg/ml) which inhibit cell growing compared to the control and this
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