Background: Exposure to microwaves radiation from microwave oven may be harmful for users especially for the one who have highest contact with microwave oven. Because the body is electrochemical in nature, any force that disrupts or changes human electrochemical events will affect the physiology of the body by destabilization and interruption of many chemical body substance including growth factors.The insulin-like growth factors (IGFs) are a family of mitogenic proteins that control growth, differentiation, and the maintenance of differentiated function in numerous tissues. It fulfils an important role in growth and development of teeth, mandible, maxillae, and tongue. Platelet derived growth factors (PDGF) are proteins that regulate cell growth and division. In particular, it plays a significant role in blood vessel formation (angiogenesis). It seems that IGF and PDGF share in much tissue developmental process. Therefore they included in the present study in correlation to tooth growth & development. This study Illustrates the expression of insulin like growth factor and platelet derived growth factor by dental cells of rat embryos at periods of gestation 16th,18thday intrauterine life(I.U.L) and one day neonatal life. Materials and Methods: Animal model: Thirty-six female rats were used in this study .Starting from zero days (time of gestation that recorded) the pregnant rats were divided into three groups. Group A serve as a control, groups B exposed to microwave oven radiation For (15 /minutes; 5/min /hour for 3 hours continuously) daily and C exposed to EMF radiation for (45 minutes ;15 min /hour for3hours continuously)daily starting from zero day of gestation till the last day. The embryo of rats at 16thday and 18th day of intrauterine life and one day old rat (new born rat) were studied immunohistochemically for localized of platelet derived growth factor (PDGF) and insulin growth factor (IGF) markers. Results:The results showed that experimental group (B) exposed to short duration of radiation (5/ min.) stimulates the development of tooth germ and faster tooth growing in comparison to control with immunohistochemical results show strong to moderate intense stain for positive expression of growth factors(PDGF,IGF) by dental tissue.For long exposure period of radiation( group C) , it showed retardation in the tooth growth withimmunohistochemical findings record weak to negative intense stain for the expression of growth factors(PDGF,IGF) by dental tissue. Conclusion: Exposure to microwave (oven) radiation during pregnancy may play a role in the expression of IGF and PDGF by cells of tooth germ thatinfluence on cell differentiation and physiological activity of specialized dental cells, depending on exposure time.
Abstract
In the present work, thermal diffusivity and heat capacity measurements have been investigated in temperature range between RT and 1473 K for different duplex stainless steel supplied by Outokumpu Stainless AB, Sweden. The purpose of this study is to get a reliable thermophysical data of these alloys and to study the effect of microstructure on the thermal diffusivity and heat capacity value. Results show the ferrite content in the duplex stainless steel increased with temperature at equilibrium state. On the other hand, ferrite content increased with increasing Cr/Ni ratio and there is no significant effect of ferrite content on the thermal diffusivity value at room temperature. Furthermore, the heat capacity of all sam
... Show MoreSingle Point Incremental Forming (SPIF) is a forming technique of sheet material based on layered manufacturing principles. The sheet part is locally deformed through horizontal slices. The moving locus of forming tool (called as toolpath) in these slices constructed to the finished part was performed by the CNC technology. The toolpath was created directly from CAD model of final product. The forming tool is a Ball-end forming tool, which was moved along the toolpath while the edges of sheet material were clamped rigidly on fixture.
This paper presented an investigation study of thinning distribution of a conical shapes carried out by incremental forming and the validation of finite element method to evaluate the limits of the p
... Show MoreThis paper analyzes a piled-raft foundation on non-homogeneous soils with variable layer depth percentages. The present work aims to perform a three-dimensional finite element analysis of a piled-raft foundation subjected to vertical load using the PLAXIS 3D software. Parametric analysis was carried out to determine the effect of soil type and initial layer thickness. The parametric study showed that increasing the relative density from 30 % to 80 % of the upper sand layer and the thickness of the first layer has led to an increase in the ultimate load and a decrease in the settlement of piled raft foundations for the cases of sand over weak soil. In clay over weak soil, the ultimate load of the piled raft foundation w
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KE Sharquie, AA Noaimi, AG Al-Ghazzi, Journal of Dermatology & Dermatologic Surgery, 2015 - Cited by 19
A novel series of chitosan derivatives were synthesized via reaction of chitosan with carbonyl compounds and grafted it’s by with different amine compounds substituted hydrogen. The produced polymers were characterized by different analyses FTIR, 1HCNMR, XRD, DSC and TGA. Solubility in water as well as many solvent was investigated, antibacterial activity of chitosan and its derivatives against two types of bacteria E. coli and S. aureus was also investigated. The results showed that derivatives sort of have antibacterial activities against Esherichia coli (Gram negative) better than chitosan whilst compound IX has better antibacterial against Staphylococcus aureus (Gram positive). SEM analysis showed that increase of surface roughness wi
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In this research a study of the effect of quality, sequential and directional layers for three types of fibers are:(Kevlar fibers-49 woven roving and E- glass fiber woven roving and random) on the fatigue property using epoxy as matrix. The test specimens were prepared by hand lay-up method the epoxy resin used as a matrix type (Quick mast 105) in prepared material composit . Sinusoidal wave which is formed of variable stress amplitudes at 15 Hz cycles was employed in the fatigue test ( 10 mm )and (15mm) value 0f deflection arrival to numbers of cycle failure limit, by rotary bending method by ( S-N) curves this curves has been determined ( life , limit and fa
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In this study, ultraviolet (UV), ozone techniques with hydrogen peroxide oxidant were used to treat the wastewater which is produced from South Baghdad Power Station using lab-scale system. From UV-H2O2 experiments, it was shown that the optimum exposure time was 80 min. At this time, the highest removal percentages of oil, COD, and TOC were 84.69 %, 56.33 % and 50 % respectively. Effect of pH on the contaminants removing was studied in the range of (2-12). The best oil, COD, and TOC removal percentages (69.38 %, 70 % and 52 %) using H2O2/UV were at pH=12. H2O2/ozone experiments exhibited better performance compared to
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The present work aims to improve the flux of forward osmosis with the use of Thin Film Composite membrane by reducing the effect of polarization on draw solution (brine solution) side.This study was conducted in two parts. The first is under the effect of polarization in which the flux and the water permeability coefficient (A) were calculated. In the second part of the study the experiments were repeated using a circulating pump at various speeds to make turbulence and reduce the effect of polarization on the brine solution side.
A model capable of predicting water permeability coefficient has been derived, and this is given by the following equations:
Z=Z0 +C.R.T/9.8(d2/D2+1) [Exp. [-9.8(d
Soil is considered one of the main factors of subsidence phenomena which
became continually happen in Baghdad (Ghazalia, Ameria, and Hay al-Amyl)
causing bad effects as shortage of drinking water, traffic jam and formation
swamps.
This thesis depends on soil study to a depth 15 meters, due to its
importance in subsidence. This done through specifying its chemical physical
properties.
Soil within Iraq climate, in case of water stopping for any reason it contract
and shrink away especially when it exposed to high pressure these factors
finally caused subsidence. In case of leakage underground water or that of
damaged water pipes this will contribute to chemical reactions which damage soil
structure and incr
The finite element method has been used in this paper to investigate the behavior of precast reinforced concrete dapped-ends beams (DEBs) numerically. A parametric investigation was performed on an experimental specimen tested by a previous researcher to show the effect of numerous parameters on the strength and behavior of RC dapped-end beams. Reinforcement details and steel arrangement, the influence of concrete compressive strength, the effect of inclined load, and the effect of support settlement on the strength of dapped-ends beams are examples of such parameters. The results revealed that the dapped-end reinforcement arrangement greatly affects the behavior of dapped end beam. The failure load decreases by 25% when
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