Alternation of bacterial antioxidant defense pathways might affect susceptibility to antibiotics in dual ways. Using a relatively simple model based on wild-type and oxyR Escherichia coli mature biofilms, their counterpart planktonic cultures and exponentially growing planktonic cultures, we explored the role of OxyR-mediated metabolism alternations in modulation of susceptibility to antibiotics ciprofloxacin and cefotaxime. All three types of cultures were placed in fresh medium,1 h after antibiotics were added and incubation continued further for 2 h. Killing rates of antibiotics were determined, biofilm eradication using crystal violet assay was estimated, expression of rpoS, katG, sulA genes as well as HPI and HPII catalase activity were measured. Biofilms of both strains were more recalcitrant to ciprofloxacin and cefotaxime at all tested concentrations compared to exponentially growing planktonic cultures. In oxyR biofilms killing rate of ciprofloxacin was lower, and killing rate of cefotaxime was higher compared to the parental strain. Compared to biofilms, wild-type biofilm counterpart planktonic cultures showed higher tolerance to low doses of ciprofloxacin, while oxyR plankton demonstrated higher tolerance to cefotaxime. Higher recalcitrance of oxyR biofilms to ciprofloxacin may be caused by an increase in persister cells under conditions of enhanced oxidative stress and activated SOS response.
UML (Unfiled Modeling Language), known as the standard method for object-oriented (analysis and design) modeling, includes other languages which enables it to implement a prototype of the structure and behaviors of the product. This paper attempts to explore the observations about UML role on the cost of software maintenance, and hence on the Total Cost of Ownership (TCO) of a software product. It is therefore important to investigate the benefits obtained through modeling..
This paper includes simulating an electron gun design to investigate the effect of the distance between the cathode and the Wehnelt cylinder bore on the quality of the ion beam emittance and to obtain the best distance of that geometrical factor. A study of a group of designs was conducted to find this distance. The SIMION8.0 program has been used to calculate the trajectories of the electrons with initial kinetic energy of (0.1 eV) and electron current of (1×10-12 A). The investigation also includes comparisons between the equipotential line trajectories for each design as well as the field distribution and the electron trajectories. The best emittance distance was concluded to be (3 mm).
The electronic payment systems are considered the most important infrastructure for the work of banks, particularly after a steady and remarkable development in information and communication technology, Which created the reality of the work of the infrastructure for these systems and these systems also become one of the most important components of infrastructure for the work of banks, cause it is one of the most important channels through which the transfer of cash, financial instruments between financial institutions in general and banking in particular.
In order to achieve the objectives of the research, the most important to identify the concept of electronic payment systems, and its divisions, and th
... Show MoreA field experiment was carried out during the 2020 season at the College of Agricultural Engineering/ University of Baghdad, Al-Jadriya to evaluate the effect of dry farming when applying water stress under the subsurface drip irrigation system on water productivity and rice yield. The experiment was conducted with three levels of irrigation water stress when 10, 20 and 40% of the available water was depleted and in three dimensions between drip lines 10, 15 and 20 cm. The experiment was designed according to a randomized complete block design, according to the split plot design, with three replications. Determine the depth of irrigation water depending on the moisture depletion of th
In this research prepared two composite materials , the first prepared from unsaturated polyester resin (UP) , which is a matrix , and aluminum oxide (Al2O3) , and the second prepared from unsaturated polyester resin and aluminum oxide and copper oxide (CuO) , the two composites materials (Alone and Hybrid) of percentage weight (5,10,15)% . All samples were prepared by hand layup process, and study the electrical and thermal conductivity. The results showed decrease electrical conductivity from (10 - 2.39) ×10-15 for (Up+ Al2O3) and from (10 - 2.06)×10-15 for (Up+ Al2O3+ CuO) .But increase thermal conductivity from( 0.17 - 0.505) for (Up+ Al2O3) and from (0.17 - 0.489) for (Up+ Al2O3+ CuO).
The effect of thermal treatment on optical constants of pure PMMA and with addition (15 and 35) ml of coumarin at different temperatures (100, 110 and 120) C0 for 1 hour were investigated. Cast method used to prepares films of pure PMMA and PMMA with (15 and 35) of coumarin. UV/VIS spectrometer technique used to measure the absorption spectra for these films. The optical constant (absorption spectra and absorption coefficient) don’t changes after applied temperatures in pure PMMA film but the optical constant (absorption spectra and absorption coefficient) in PMMA with (15 and 35) ml of coumarin increased with applied temperatures. The optical energy gap of pure PMMA and PMMA with (15 and 35) ml of coumarin sl
... Show MoreUrbanization phenomenon did expand rapidly in Baghdad-Iraq due to security improvement and the human desire for daily services availability, where reducing the agricultural lands "Greenlands" negatively affected the climate rate. The relationship between urban expansion and relative humidity was studied from 2008 to 2018 using remote sensing data (satellite images of Landsat 5 and Landsat 8) and relative humidity rate data obtained from the European Centre for Medium-Range Weather Forecasts (ECMWF). Data were processed and analyzed using ArcGIS v: 10.2. Results showed changes in human activities (land use (LU)) and urban areas, where increasing urbanization declines vegetation and turbulence climate. The study provides a signi
... Show MoreDouble hydrothermal method was used to prepare nano gamma alumina using aluminum nitrate nano hydrate and sodium aluminate as an aluminum source, CTAB (cetyltrimethylammonium bromide) as surfactant, and variable acids: weak acids like; citric, and acitic acids, and strong acids like; hydrochloric and nitric acids as a bridge between aluminum salts and surfactant. Different crystallization times 12, 24, 48, and 72 hrs were applied. All the batches were prepared at pH equals to 9. XRD diffraction technique was used to investigate the crystalline nano gamma alumina pure from surfactant. N2 adsorption-desorption (BET) was used to measure the surface area and pore volume of the prepared nano alumina, the average p
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