Bending effects on the transmission of optical signal are investigated on a single mode
optical fiber (SMOF) of 10 m length, core radius of 5 μm and optical refractive index difference
0.003. The bending radii (R) were between 0.08 and 0.0015 m. A great decrease in the amplitude is
shown for radii below 0.01 m. Sudden break down occurs for radii less than 0.0015 m. Birefringence
(B) is difficult to measure for long fibers. Meanwhile, B was found by comparing with calibrated
fiber of the same properties but of length of 0.075 m. The results show an increase in propagation
constant (Δβ) and the decrease in beat length (Lb), and show that bending decreases the critical radius
of curvature (Rc) related to B. The changes induced on the initial phase of the signal are shown for
bending curvatures of radii 0.06, 0.03 and 0.005 m. The linear phase retardation is found to increase
more rapidly for bends of R< 0.05 m. The degree of polarization decreases smoothly for bends of
R>0.01m. Below this curvature, the fluctuation and great instability in the polarization- state of the
output signal are easily detected. All these features are very important in using SMOF in sensitive
optical devices especially in long distance fiber communications.
This research includes a study of Methylenetetrahydrofolate reductase gene’s allele 677C?T and its correlation with oxidative stress and their impact on female infertility. Fifty infertile women with the range age (23-42) years and twenty five fertile women with the range age (22-39) years as control group living in Erbil city were selected. The serum level of Malondialdehyde (MDA), superoxide dismutase (SOD), prolactin hormone (PRL), Luteinizing hormone (LH), Thyroid stimulating hormone (TSH), Triiodothyronine hormone (T3), and Thyroxine hormone (T4) were measured, also a body mass index (BMI) was calculated. A restriction enzyme (Hinf1) was used to improve the mutation in DNA bands of infertile women. The results showed significant inc
... Show MoreObjectives: To find out the effectiveness of education program application on nurses-midwives' knowledge toward prevention and management of postpartum hemorrhage in delivery room and some socio demographic characteristics Methodology: a quasi -experimental "test-retest"design has carried throughout the present study with the application of a pre –test and post- test for nurses-midwives' knowledge toward postpartum hemorrhage. The study was conducted in six hospitals in Baghdad: Fatima Al – Zahra for Maternity and Pediatric, Al -Elwia maternity, Baghdad Teaching, AL-Imamine Al - Kadhimin Teaching, Al-Karckh maternity and Al-Yarmouk Teaching hospital for the period from 27th May
... Show Moreew sports technologies have highlighted the importance of perceptual – cognitive training in order to optimize performance in sports e.g., dynamic team sport such as basketball. Augmented motor reality AMR is a new training model based on realistic movement combined with interactive virtual cues that may be useful to enhance spatial orientation and decision making. The purpose of this study was to investigate the effects of an AMR-based training program on spatial awareness and skill-based decision making in youth basketball players. Twenty-four male young basketball players aged 15.2±0.8 years were randomized to the experimental group n=12, receiving AMR training, and control group n=12, performing conventional practice. The interventio
... Show MoreThis paper compare the accurecy of HF propagation prediction programs for HF circuits links between Iraq and different points world wide during August 2018 when solar cycle 24 (start 2009 end 2020) is at minimun activity and also find out the best communication mode used. The prediction programs like Voice of America Coverage Analysis Program (VOACAP) and ITU Recommendation RS 533 (REC533 ) had been used to generat HF circuit link parameters like Maximum Usable Frequency ( MUF) and Frequency of Transsmision (FOT) .Depending on the predicted parameters (data) , real radio contacts had been done using a radio transceiver from Icom model IC 7100 with 100W RF
... Show MoreBackground: Pain and the usage of local anesthetic agents are still real problem in pediatric dentistry, for these reasons, the use of minimal invasive dentistry (MID) in regard to the patient comfort is important especially for children, anxious and uncooperative patients. Chemomechanical caries removal (CMCR) methods involve the selective removal of the carious dentine hence it avoided the painful removal of the sound dentine and the anxiety resulted due to the vibration of the hand piece which is also decreased thus it appears to be more acceptable and comfortable to the patient. Aims of this study: This study was conducted among group of children to assess and compare the anxiety rating scale (during and after treatment) between the
... Show MorePolycystic ovary syndrome (PCOS) is a complex endocrine–metabolic disorder characterized by hyperandrogenism, ovulatory dysfunction, insulin resistance, and chronic inflammation resulting in reproductive and metabolic complications. Traditional metformin therapy improves insulin sensitivity, while newer dual incretin agonists, such as tirzepatide, may offer broader metabolic and ovarian protection. The objective of this study is to investigate whether tirzepatide could alter hormonal parameters, metabolism, inflammation, and histopathology of a testosterone propionate–induced PCOS rat model compared with metformin. Thirty prepubertal female Wistar rats were divided into five groups (n = 6). PCOS was induced by testosterone propionate (1
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