A total of (25) stool samples were collected from children and adults (2- 4) years old suffering from diarrhea to isolate E. coli strains that produce heat-stable enterotoxin a (STa), and after performing microscopic examination, cultural characterization and biochemical identification only (11) isolates showed positive E. coli. STa activity was estimated by using suckling mouse assay (SMA) and from these (11) isolates only (5) showed STa activity and the one with the highest STa activity was selected for large scale production of STa, which was followed by partial purification using ion-exchange chromatography (normal phase) using DEAE sephadex A-50 column. After purification and determination of protein concentration by using the standard curve of bovine serum albumin, the concentration of toxin-protein was estimated as (1.08) mg/ml. The specific activity varied from (350) U/mg protein at the first step of purification to (2366.6) U/mg protein at the final step, while the final purification of the toxin was about (6.76) fold and with a yield of (18.25) %
Abstract
This work deals with a numerical investigation to evaluate the utilization of a water pipe buried inside a roof to reduce the heat gain and minimize the transmission of heat energy inside the conditioning space in summer season. The numerical results of this paper showed that the reduction in heat gain and energy saving could be occurred with specific values of parameters, like the number of pipes per square meter, the ratio of pipe diameter to the roof thickness, and the pipe inlet water temperature. Comparing with a normal roof (without pipes), the results indicated a significant reduction in energy heat gain which is about 37.8% when the number of pipes per m
... Show MoreBackground: Bacteriocin is a peptidic toxin has many advantages to bacteria in their ecological niche and has strong antibacterial activity. Objective: The aim of this study was to evaluation of bacteriocin using Streptococcus sanguinis isolated from human dental caries.
Subjects and Methods: Thirty five streptococcus isolates were diagnosed and tested for their production of bacteriocin, and then the optimal conditions for production of bacteriocin were determined. After that, the purification of bacteriocin was made partially by ammonium sulfate at 95% saturation levels, followed by and gel filtration chromatography
... Show MoreThermal energy storage is an important component in energy units to decrease the gap between energy supply and demand. Free convection and the locations of the tubes carrying the heat-transfer fluid (HTF) have a significant influence on both the energy discharging potential and the buoyancy effect during the solidification mode. In the present study, the impact of the tube position was examined during the discharging process. Liquid-fraction evolution and energy removal rate with thermo-fluid contour profiles were used to examine the performance of the unit. Heat exchanger tubes are proposed with different numbers and positions in the unit for various cases including uniform and non-uniform tubes distribution. The results show that
... Show MoreNutrient agar medium with various concentrations of cefotaxime was used for isolation spontaneous mutants from wild type strain of P.aeruginosa PHA-1. Eighty-two mutants were successfully isolated with the viable count 52×107 , these mutants were confirmed as spontaneous not physiological adaption mutants by reculture on the same medium. Then, wild type PHA-1 and mutants were examined for production pyocyanin; a blue greenish pigment was clearly noticed on King A medium. Remarkably the mutant strain named S300-8 was distinguished in productivity in comparison with wild type strain PHA-1; the amount of pigment was 56.0667mg/l and 74.53mg/l respectively. In addition, pyocyanin produced by mutant strain S300-8 revealed a potent efficacy again
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The current study was carried out to reveal the plasma parameters such as ,the electron temperature ( ), electron density (ne) , plasma frequency (fp), Debye length ( ) , Debye number ( for CdS to employ the LIBS for the purpose of analyzing and determining spectral emission lines using . The results of electron temperature for CdS range (0.746-0.856) eV , the electron density(3.909-4.691)×1018 cm-3. Finally ,we discuss plasma parameters of CdS through nano second laser generated plasma .
In this study, a system of nonthermal plasma that was operated under atmospheric pressure and was powered by argon gas was employed. The particular plasma properties are affected by changes in the Ar gas flow ranges from 0.5 to 2.5 l/min, product by stream of the plasma jet that is utilized. By using the aforementioned method generated from AC and DC. After placing Ar gas as the cathode, which represents the negative pole, flows toward the anode, which is represented by a tiny metal plate of Zn measuring 6 × 1 cm2 in size, with a submerged part of 4 cm2 long, with both types of current employed having a high voltage of 13.5 kV and the frequency of AC was 30 kHz, we measured these variable parameters. It has been shown that when argon f
... Show MoreLet R be a commutative ring with non-zero identity element. For two fixed positive integers m and n. A right R-module M is called fully (m,n) -stable relative to ideal A of , if for each n-generated submodule of Mm and R-homomorphism . In this paper we give some characterization theorems and properties of fully (m,n) -stable modules relative to an ideal A of . which generalize the results of fully stable modules relative to an ideal A of R.
The current study was conducted on 504(Ros-308) broiler chicks during the period 28/9/2017-9/11/2018to determine the effect of heat shock in early age and additives such as ginseng in three levels on birds weight and feedconsumption. Results showed that the exposure to high temperature (38-400C) lead to significant decrease (p≤≤≤≤≤0.05 (inaverage body weight at7 day of age and significant decrease in body weight in birds expousured to high temperature inthe periods 2, 4 and 6 hours compared with control (Table 1). Significant decrease in live body weight when exposure to2hr compared with 6hr namely (138.54) and (144.21), respectively while no significant difference between 2 and 4h.Results showed no significant effect in body we
... Show MoreEnterotoxin of Vibrio cholerae was extracted by cooling centrifuge at 6.000 rpm for 30 minntes. and filtrated by using milipore filter (0.22 ?m). The effect of crude enterotoxin on phagocytosis was studied by measuring the phagocytic index for 20 blood sample which were collected from healthy people and treated with enterotoxin in addition to control samples. From the results we found that phagocytic index of blood sample which were treated with enterotoxin was 42.9% while the phagocytic index of control blood samples was 64%. This means that there is a negative effect for the enterotoxin resulted from vibrio choleaa on the activity of phagocytic index.
ABSTRACT Possible interference of vamin nutritional solution with the activity of several B-lactam antibiotics against E.coli was evaluated in vitro.In Minimal basal salts-glucose medium rapid growth inhibition of sensitive E. coli was induced by 4 µg/ml of ampicillin / cloxaillin, 8 µg/ml of ampicillin, 6 µg/ml of carbencillin, hostacillin, and cephalotin, and by 32 µg/ml of penicillin G and cloxacillin. Significant inactivation of up to 32 µg/ml of carbencillin, cephalotin, penicillin G, and hostacillin was induced by addition of 1:20 v/v vamin. This inactivation was due to the presence of specific amino acids in the mixture. Deletions of amino acids revealed that valine, leucine, isoleucine, tyrosine, tryptophan, phenylalanine, cys
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