Al-Mustansiriyah Journal of Science

The work studied the relationship between polar jet stream and surface low pressure in April\'s months during years from 2014 to 2016 which the polar jet passes with high frequencies over the area of study. The study presents the structure of polar jet that affects significantly in the intensity of the low pressure system at the surface. The structuredid not repeat regularly during April\'s months for the years from 2014 to 2016 and it was two structures, continuous and discontinuous with different percentage ratios from a year to year. The percentages ratios of discontinuous jet-types were in2014 about 36 %, 6 % in 2015, 92 % in 2016 which declared to estimate low pressure center value on the surface which need the corrected recognizing the polar jet-type depending on its structure. The relationship between low pressure center value and the lowest polar jet geopotential height was during April 2014 which was generally direct relationship with continuous jet-type while it was indirect relationship with discontinuous jet-type. The mixing continuous and discontinuous jet-types data in same year will distorted that relationship. The discontinuous jet-type structure was significant to limit the relationship between low pressure center on surface and geopotential height which was direct relationship with small ratio of discontinuous as April 2015 jet-type and high ratio as April 2016 while with ratio near from middle as April 2014 relationship was distorted. The study also revealed the low pressure center value would be less withthe discontinuous jet-type if there were same geopotential height values of continuous and discontinuous jet-type

Background: Carbapenems are usually the choice of antimicrobial agents in infections produced by Enterobacteriaceae bacteria-producing ESBL (extended spectrum β-lactamases). Carbapenemase production among clinical isolates of Enterobacteriaceae has been widely reported and Resistance to carbapenems group is generally due to production of Carbapenemases. Phenotypic determination and distinction of Carbapenemases in drug-resistant gram-negative is crucial for appropriate infection control. Materials and Methods: Carbapenemase production among Enterobacteriaceae isolates was identified phenotypically using a commercially available EDTA-combined disc diffusion test containing inhibitors to the various carbapenemase classes and Modified Hodge test (MHT). Results: A total of 98 Enterobacteriaceae isolates were included, 42(42.8%) were Multi-drug resistant (MDR), 27(27.5%) were XDR while 8(8.2%) exhibited pan-drug resistance (PDR). Of the 74 isolates of Escherichia coli and 24 Klebsiella pneumoniae that were positive for carbapenemase production, 12 (16.2%) and 9 (37.5%) were Metallo beta-lactamase (MBL) producers respectively, Hence, the overall prevalence of carbapenemase-producing Escherichia coli and Klebsiella pneumoniae in this study were 47.3% and 87.5%. Conclusion: Carbapenemase-producing Enterobacteriaceae was indeed recognized in our hospitals. The EDTA-combination disk test was a rapid, cost-effective and suitable method which will be able to identify and distinguish the carbapenem-resistant bacterial isolates within the hospitals especially when molecular detection techniques are not available.

This paper concerned with the solution of the nanoscale structures consisting of the with an effective mass envelope function theory, the electronic states of the quantum ring are studied. In calculations, the effects due to the different effective masses of electrons in and out the rings are included. The energy levels of the electron are calculated in the different shapes of rings, i.e., that the inner radius of rings sensitively change the electronic states. The energy levels of the electron are not sensitively dependent on the outer radius for large rings. The structures of quantum rings are studied by the one electronic band Hamiltonian effective mass approximation, the energy- and position-dependent on electron effective mass approximation, and the spin-dependent on the Ben Daniel-Duke boundary conditions. In the description of the Hamiltonian matrix elements, the Finite elements method with different base linear triangular element is adopted. The non-linear energy confinement problem is solved approximately by using the Finite elements method with linear triangular element, to calculate the energy of the electron states for the quantum ring.

The purpose of this paper is to find best multiplier approximation of unbounded functions in L_(p,∅_n ) –space by using Trigonometric polynomials and by de la Vallee- Poussin operators. Also we will estimate the degree of the best multiplier approximation by Weighted –Ditzian-Totik modulus

The aim of this work is to deal with a new integrable nonlinear equation of wave propagation, the combined of the Korteweg-de vries equation and the negative order Korteweg-de vries equation (combined KdV-nKdV) equation, which was more recently proposed by Wazwaz. Upon using wave reduction variable, it turns out that the reduced combined KdV-nKdV equation is alike the reduced (3+1)-dimensional Jimbo Miwa (JM) equation, the reduced (3+1)-dimensional Potential Yu-Toda-Sasa-Fukuyama (PYTSF) equation and the reduced (3 + 1)¬dimensional generalized shallow water (GSW) equation in the trav¬elling wave. In fact, the four transformed equations belong to the same class of ordinary differential equation. With the benefit of a well known general solutions for the reduced equation, we show that sub¬jects to some scaling and change of parameters, a variety of families of solutions are constructed for the combined KdV-nKdV equation which can be expressed in terms of rational functions, exponential functions and periodic solutions of trigonometric functions and hyperbolic func¬tions. In addition to that the equation admits solitary waves, and double periodic waves in terms of special functions such as Jacobian elliptic functions and Weierstrass elliptic functions.

Nanoparticles of semiconductor material have get more interest due to their desirable properties and applications in different areas. In this study Zinc Oxide Nanoparticles (ZnO NPs) were synthesized using laser ablation in water by applying (1600 pulses) of Nd- YAG laser ( λ = 1064 nm ) . The crystal structure morphology of synthesized ZnO NPs were investigated using X-Ray diffraction, atomic force microscope (AFM) , optical microscope image , and optical properties characterized using UV-VIS as well as FTIR spectroscopy . The investigation revealed high purity of the ZnO NPs thin film prepared with a regular and homogeneous semi-spherical shape nanoparticles distribution on the substrate surface with size around 50nm. The optical properties shows energy band gap (1.5 and 4) eV respectively. I-V characteristics have been studied for the heterojunction structure of (Ag/ZnO/Si/Al) indicates that this heterojunc-tion could be used as a solar cell with efficiency about 10.9%.

This work aims to use the color distribution of galaxies to differentiate between blue and red galaxies. The photometric data of 300000 galaxies at redshift of z = 0 – 0.15 were collected from the Sloan Digital Sky Survey (SDSS). Three redshift ranges were considered for the purpose of this work: 100000 galaxies at z = 0-0.05, 100000 galaxies at z = 0.05-0.1 and 100000 galaxies at z = 0.1-0.15. The color distributions for all redshift ranges were determined. The results have clearly shown that the color distributions for all redshift ranges are bimodal. One of the two peaks corresponds to the blue galaxies (young and star-forming galaxies), whereas the other peak corresponds to the red galaxies (old and non-star-forming galaxies). Therefore, the color distribution of galaxies can be considered as an efficient tool to distinguish between blue and red galaxies.

In this work, thin films of lead iodide (PbI2) were deposited on glass substrates with different thicknesses by vacuum thermal evaporation method. The structural, chemical, electrical and optical characteristics of the thin films were studied. XRD analysis showed that lead iodide film is polycrystalline having hexagonal structure. A particle size was estimated by Williamson - Hall technique (13) nm and strain (4.90*10-3) are founded from the intercept with y-axis and slope for PbI2. The UV-VIS measurements illustrated that the lead iodide has a direct optical band gap and Urbach energy to be 0.677 eV2. Raman peaks are detected at 70, 96, 99.5, 188 and 202 cm-1 which corresponding to characteristic of PbI2 at (E21, A11, 2E11 and A1g). The FTIR spectrum of PbI2 thin film showed six bands at 1650, 1900, 3100, 3400, 3600 and 3800 cm-1. Mechanism of dc transport was also analyzed in the temperature range 315–395 K. Also the variation of reflectivity in the range near infrared is conductive generally attributed to thin film nature, where this film contain light scattering and large surface area, which enhance the optical absorption and hence, a low reflectivity is obtained.

In this study, a sensitive technique (Broadband Cavity Enhanced Absorption Spectroscopy (BBCEAS)) is employed for measuring the absorption of thin films deposited onto a glass substrate. A thin film of the biological solution such as Lyophilied Bovine haemoglobin is deposited on glass microscope coverslips. Drop coating method was used to deposit a thin film over the microscope coverslips. The number of passes is calculated: 612 passes for the high reflectivity mirror were obtained. The best measurements are made with the mirror set of reflectivity of (R≥ 0.99) which produced an αmin value of 0.0043 cm-1 and LOD of 1.9×10-7M.