The need for optical fibers has emerged for its ability to transmit information with less attenuation and over long distances. In this work, four optical fibers with core radii from 1 μm to 4.75 μm in steps of 1.25 μm and a numerical aperture of 0.17 were studied and their modes properties have been calculated at a wavelength of 633 nm by using RP Fiber Calculator (free version 2022). Also, the effect of increasing the core radius on these properties has been studied. Multimode fibers can be obtained when the radius of the fiber core is large compared to the operating wavelength of the fiber which is less than the cutoff wavelength of the mode. Otherwise, a single-mode fiber is obtained. It has been concluded that all the calculated p
... Show MoreBackground: Astrocytic tumors are the most common primary tumors of the central nervous system. Several grading systems are used to grade astrocytomas. The most widely used system is the World Health Organization (WHO) classification (1979, 1993, 2000, and 2007) that grades astrocytomas (I-IV) based on cytological atypia, mitotic activity, vascular proliferation, and necrosis: pilocytic astrocytoma (grade I), diffuse astrocytoma (grade II), anaplastic astrocytoma (grade III), and glioblastoma (grade IV).
Objectives: The aim of this study is to evaluate p53 over expression , Ki-67 expression in astrocytomas and Correlate these two markers with histologic grade of astrocytomas.
Methods: Formalin fixed, paraff
Micro metal forming has an application potential in different industrial fields. Flexible tool-assisted sheet metal forming at micro scale is among the forming techniques that have increasingly attracted wide attention of researchers. This forming process is a suitable technique for producing micro components because of its inexpensive process, high quality products and relatively high production rate. This study presents a novel micro deep drawing technique through using floating ring as an assistant die with flexible pad as a main die. The floating ring designed with specified geometry is located between the process workpiece and the rubber pad. The function of the floating ring in this work is to produce SS304 micro cups with profile
... Show MoreIn Paracoccus denitrificans Pd1222 bacterium, Pden_3633 encoding gene has been nominated to encode for Isovaleryl CoA dehydrogenase (IVDH) [1], the enzyme which involve in leucine catabolism pathway. In this study, this putative IVDH was investigated. IVDH encoding gene from P. denitrificans Pd1222 in addition to desired features for cloning, expression and purification have been designed and synthesized. The synthetic coding sequence was expressed in Escherichia coli. The enzyme was purified as a Strep-Tagged protein with a total protein 220.5 mg. An apparent molecular weight of 42.9 kDa was determined on SDS gel. Amino acid alignment showed a very high similarity (91-96%) with corresponding IVDH from several other Paracoccus species. A
... Show MoreThis study was aimed to use plant tissue culture technique to induce callus formation of Aloe vera on MS. Medium supplied with 10 mg/l NAA and 5 mg/l BA that exhibit the best results even with subculturing. As the method of [1] 1g. dru weight of callus induced from A. vera crown and in vivo crown were extracted then injected in HPLC using the standards of Ascorbic acid (vit. C), Salysilic acid and Nicotenic acid (vit. B5) to compare with the plant extracts. Results showed high potential of increasing some secondary products using the crown callus culture of A. vera as compared with in vivo crown, Ascorbic acid was 1.829 ?g/l in in vivo crown and increased to 3.905 ?g/l crown callus culture . Salysilic acid raised from 3.54 ?g/l in in vivo c
... Show MoreGender has considered and become a new trend in women's studies, as it reflects the behaviors, roles and attitudes imposed by society on its members in accordance with their biological nature,with focusing on gender rather than on concentration on women, which is closely linked to the vision that concentrates on women's problems which are not primarily according to their biological differences But rather to a greater extent to social, cultural, historical and religious barriers and Obstacles.
Therefore, the qualitative division due to the concept of "gender" is not a rigid biological division, but is relied on the broad general context through which the social division of work is done. Thus, content in the pages of Facebook with high-
The increasing demand for energy has encouraged the development of renewable resources and environmentally benign fuel such as biodiesel. In this study, ethyl fatty esters (EFEs), a major component of biodiesel fuel, were synthesized from soybean oil using sodium ethoxide as a catalyst. By-products were glycerol and difatty acyl urea (DFAU), which has biological characteristics, as antibiotics and antifungal medications. Both EFEs and DFAU have been characterized using Fourier transform infrared (FTIR) spectroscopy, and 1H nuclear magnetic resonance (NMR) technique. The optimum conditions were studied as a function of reaction time, reactant molar ratios, catalyst percentage and the effect of organic solvents. The conversion ratio of soybea
... Show MoreBackground: Human parvovirus B19 (B19V) is the only human pathogenic parvovirus, It is highly erythrotropic and preferentially replicates in erythroid progenitor cells (EPCs). Recently the effects of B19 infection have been well studied in children with acute lymphoblastic leukemia (ALL).
Objective: To detect parvovirus B19 among children with ALL.
Methods: A cross sectional study involved forty five patients with ALL (21 patients were newly diagnosed ALL and 24 children who underwent chemotherapy) who were attending department of oncology in Children's Welfare Teaching Hospital in Baghdad Medical City between December 2012 and April 2013, compared to forty five of appare
... Show MoreThe Polarographic study of the interaction between ascorbic acid and Ni+2 was carried out at dropping mercury electrode [DME] . This study included the determination of the kinetic parameters (kfh ,n) and thermodynamic parameters such as enthalpy change (H), free energy change (G) and entropy change (S) of Ni+2 complexes with ascorbic acid in 0.1 M KCl solution over the temperature rang of (294-309)K. The electrode processes were irreversible and diffusion controlled.