أجريت هذه الدراسة في محافظة النجف بالعراق لتحليل عينات بيولوجية من المدخنين وغير المدخنين. تم استخدام العينات، بما في ذلك مصل الدم والبول والشعر والأظافر، كمؤشرات حيوية لتحديد تركيزات اليورانيوم (UC) ونظائره (238U، 235U، و234U). وباستخدام طريقة التعرض الطبيعي، تم استخدام كاشف المسار النووي (CR-39، المملكة المتحدة) لقياس تركيزات اليورانيوم في العينات. تم جمع خمسة وسبعين عينة من مصل الدم والبول والشعر والأظافر للمدخنين من الأصحاء وخمسين عينة لغير المدخنين من الأصحاء في خمس فئات عمرية لجميع العينات. اعتمدت هذه الدراسة على العمر والتدخين لمقارنة النتائج وتحديد تأثيرها على تراكيز اليورانيوم. أظهرت النتائج أن متوسط قيم تراكيز اليورانيوم في مصل الدم والبول والشعر والأظافر لدى المدخنين كان 0.180±0.042 جزء في المليون، 0.759±0.024 جزء في المليون، 0.912±0.085 جزء في المليون، و0.934±0.091 جزء في المليون، على التوالي. بينما بلغ متوسط قيم تراكيز اليورانيوم في مصل الدم والبول والشعر والأظافر لدى غير المدخنين 0.110±0.014 جزء في المليون، 0.157±0.023 جزء في المليون، 0.736±0.032 جزء في المليون، و0.756±0.024 جزء في المليون، على التوالي. وتشير النتائج والمقارنات إلى أن جميع تراكيز اليورانيوم تعتمد على المتغيرات التي بنيت عليها هذه الدراسة (العمر والتدخين). وبمقارنة تراكيز اليورانيوم لجميع العينات البيولوجية للمدخنين وغير المدخنين، كانت قيمة P ذات دلالة إحصائية عالية حيث كانت أقل من 0.001. ووفقا لنتائج عينات الدراسة، فإن متوسط قيم UC، 238U، 235U، و234U للعينات البيولوجية لدى المدخنين كانت أعلى منها لدى غير المدخنين. وبالتالي، يمكن القول أن تدخين السجائر يستخدم كمؤشر حيوي لوجود تركيزات اليورانيوم.
Free vibration behavior was developed under the ratio of critical buckling temperature of laminated composite thin plates with the general elastic boundary condition. The equations of motion were found based on classical laminated plate theory (CLPT) while the solution functions consists of trigonometric function and a continuous function that is added to guarantee the sufficient smoother of the so-named remaining displacement function at the boundaries, in this research, a modified Fourier series were used, a generalized procedure solution was developed using Ritz method combined with the imaginary spring technique. The influences of many design parameters such as angles of layers, aspect ratio, thickness ratio, and ratio of initial in-
... Show MoreHeuristic approaches are traditionally applied to find the optimal size and optimal location of Flexible AC Transmission Systems (FACTS) devices in power systems. Genetic Algorithm (GA) technique has been applied to solve power engineering optimization problems giving better results than classical methods. This paper shows the application of GA for optimal sizing and allocation of a Static Compensator (STATCOM) in a power system. STATCOM devices used to increase transmission systems capacity and enhance voltage stability by regulate the voltages at its terminal by controlling the amount of reactive power injected into or absorbed from the power system. IEEE 5-bus standard system is used as an example to illustrate the te
... Show MoreIn this work the radioactive wastes in the Old Russian
Cemetery Al -Tuwaitha site were classified according to risks for
workers who are involved in the retrieval process. The exposure
assessment results expressed as estimates of radionuclide intakes by
inhalation and ingestion, exposure rates and duration for external
exposure pathways, and committed effective dose equivalents to
individuals from all relevant radionuclides and pathways. Results
showed the presence of natural radionuclides Ra-226, Th-234 and K-
40, as well as the produced radionuclide Cs-137 and Eu-152 in the
cemetery wells. The absorbed doses from the waste were classified to
two categories; exempt waste and low level waste according to
Purpose: clarify the integrative relationship of strategic leadership skills and effective management and the role of those skills combined or individually in achieving effective management.
Research design: The researchers used the quantitative method by surveying a class sample from the heads of the executive departments in a group of Iraqi private banks, consisting of (106) individuals according to the (VUCA Prime) methodology for effective management and the ten skills model for Johansen. The questionnaire was analyzed using a model of the structural equation.
Findings: The most prominent results of the research were the presence of a weak ro
... Show MoreBackground: preparation of root canals is an important step in root canal treatment. Mechanical instrumentation of root canals cause an irregular layer of debris, known as the smear layer. As a result, several studies reported that preferring the removal of the smear layer. Objective: To study the influence of the energy (100 mJ) of Erbium, Chromium: Yttrium Scandium Gallium Garnet (Er,Cr:YSGG) laser at short pulse duration (60 μs) on smear layer removal of apical third after using Photon induced photoacoustic streaming technique. Materials and methods: Eighteen straight single-rooted mandibular premolars were used. The roots length were uniform to 14mm from the anatomic apex and
... Show MoreThe simulation of passively Q-switching is four non – linear first order differential equations. The optimization of passively Q-switching simulation was carried out using the constrained Rosenbrock technique. The maximization option in this technique was utilized to the fourth equation as an objective function; the parameters, γa, γc and β as were dealt with as decision variables. A FORTRAN program was written to determine the optimum values of the decision variables through the simulation of the four coupled equations, for ruby laser Q–switched by Dy +2: CaF2.For different Dy +2:CaF2 molecules number, the values of decision variables was predicted using our written program. The relaxation time of Dy +2: CaF2, used with ruby was
... Show MoreAbstract: Polarization beam splitter (PBS) integrated waveguides are the key components in the receiver of quantum key distribution (QKD) systems. Their function is to analyze the polarization of polarized light and separate the transverse-electric (TE) and transverse-magnetic (TM) polarizations into different waveguides. In this paper, a performance study of polarization beam splitters based on horizontal slot waveguide has been investigated for a wavelength of . PBS based on horizontal slot waveguide structure shows a polarization extinction ratio for quasi-TE and quasi-TM modes larger than with insertion loss below and a bandwidth of . Also, the fabrication tolerance of the structure is analyzed.<
... Show MoreA novel demountable shear connector for precast steel-concrete composite bridges is presented. The connector uses high-strength steel bolts, which are fastened to the top flange of the steel beam with the aid of a special locking nut configuration that prevents bolts from slipping within their holes. Moreover, the connector promotes accelerated construction and overcomes the typical construction tolerance issues of precast structures. Most importantly, the connector allows bridge disassembly. Therefore, it can address different bridge deterioration scenarios with minimum disturbance to traffic flow including the following: (1) precast deck panels can be rapidly uplifted and replaced; (2) connectors can be rapidly removed and replaced; and (
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