The importance of vibrations in rotating rotors in engineering applications has been examined, as has the best approach to interpreting vibration data. The most extensively used analytical approaches for rotating shaft vibration analysis have been investigated. In this research, a detailed study was made of the Rayleigh and Dunkerley methods due to their importance in the special calculations to find the amplitude of vibrations in the rotation system. The multi-node method was used to calculate both Dunkerley's and Rayleigh's methods. An experimental platform was built to study the vibrations that occur in the rotating shafts, and the results were compared with theoretical calculations and with different distances of the bearings. It proved that there is very little error between the experimental and theoretical results. The vibration signal from the sensors was analyzed using the LABVIEW program. Rayleigh's method was compared to the exact method, and it was considered the most accurate method. It was found that it made very little difference, up to about 0.06%. As for the Dunkerley method, the difference between it and the proper method is about 4%, which is acceptable. Then a comparison was made between Rayleigh's and Dunkerley's methods, and it was found that Dunkerley's method is the most appropriate in the calculations.
Abstract
Psoriasis is defined as a series of events that begins in its initial stage with dermatitis and then progresses to more widespread inflammation and increased oxidative stress. The aim of this study was to determine whether psoriasis and the levels of IL-15, IL-23, and TNF-α are related, the ELISA technique was used to detect the levels of inflammation in psoriasis patients and to compare them with healthy individuals. This study included 150 samples, including 90 patients with psoriasis and 60 healthy individuals, and the study was conducted from November 2021 to April 2022. The current study revealed that there was a significant difference in the level of TNF-α in the group of psoriasis patients compa
... Show MoreThis study showed that the lens in baloot muluki fish Chondrostoma regium is transparent, spherical shape, and solid in textures, while in the tree frog Hyla arborea savignyi, freshwater turtles Clemmys caspia caspia, white–eared bulbul Pycnonotus leucotis and brown rat Rattus norvegicus are transparent, soft and biconvex, it is very soft in white–eared bulbul. There are many significant differences have been recorded between the average weight lens and the total concentration of the protein in the lens all studied animals. Electrical migration process for lens proteins showed that there is one bundle of crystalline –? and one bundle also crystalline–? in all studied species, either crystalline–? may represent one bundle character
... Show MoreBackground: surgical treatment of established carpal tunnel syndrome (CTS) can be accomplished by various operative modalities, epineurotomy of the median nerve plus carpal ligament release has been advocated by many authors, This study try to evaluate the role of epineurotomy on the outcome of operative treatment of CTS postoperatively, compared to simple release only .
Patients and Methods: 48 hands of 42 patients, 34 female and 8 male. where classified in to two groups, one group had a release of the transverse carpal ligament alone, group (1). and the other group had a release plus epineurotomy of the median nerve, group (2). Selection of patients was according to the same clinical criteria regarding physical finding, periods
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This study is concerned with the estimation of constant and time-varying parameters in non-linear ordinary differential equations, which do not have analytical solutions. The estimation is done in a multi-stage method where constant and time-varying parameters are estimated in a straight sequential way from several stages. In the first stage, the model of the differential equations is converted to a regression model that includes the state variables with their derivatives and then the estimation of the state variables and their derivatives in a penalized splines method and compensating the estimations in the regression model. In the second stage, the pseudo- least squares method was used to es
... Show MoreBackground: Periodontal disease is a chronic bacterial infection that affects the gingiva and bone supporting the teeth. Smoking, which is an important risk factor for periodontitis, induce oxidative stress in the body and cause an imbalance between reactive oxygen species (ROS) and antioxidants, such as superoxide dismutase (SOD). This study aimed to evaluate the influence of smoking on periodontal health status by estimating the levels of salivary SOD level in non-smokers (controls) and light and heavy smokers and to test the correlation between the SOD enzyme level and the clinical periodontal parameters in each group. Materials and Methods: The study sample consisted of 75 male, with age ranged from 35 to 50 years. Clinically, the perio
... Show MoreThe present study aimed to establish reference normal ranges of haematological and biochemical parameters of two vertebrates (rabbits and partridges). Twenty animals (10 rabbits, 10 partridges) were used in this study. Blood samples, collected from heart of rabbits, as well from the right jugular vein of partridge, and delivered to the laboratory. Some biochemical parameters (potassium, sodium, and uric acid) have been investigated, in addition blood samples were tested for: white blood cells (WBC), red blood cells (RBC), haemoglobin (HB), haematocrit (HCT), mean corpuscular hemoglobin (MCH), mean concentration of hemoglobin in the corpuscular volume (MCHC), mean corpuscular volume (MCV).
Results indicate that haematological and bioch
Background : Although development and progress in various diagnostic methods, but still identification of remnants of skeletal and decomposing parts of human is one of the most difficult skills in forensic medicine . Gender and age estimation is also considering an important problem in the identification of unknown skull. The aims of study: To estimate volume and dimension of maxillary sinus in individuals with dentate and edentulous maxillae using CT scan, and to correlate the maxillary sinus volume in relation to gender and age. Materials and Methods : This study included 120 patients ranged from (40-69 years), divided into two groups, dentate group with fully dentate maxilla and edentulous group with complete edentulous maxilla, and e
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In this research, a study of the behavior and correlation between sunspot number (SSN) and solar flux (F10.7) have been suggested. The annual time of the years (2008-2017) of solar cycle 24 has been adopted to make the investigation in order to get the mutual correlation between (SSN) and (F10.7). The test results of the annual correlation between SSN & F10.7 is simple and can be represented by a linear regression equation. The results of the conducted study showed that there was a good fit between SSN and F10.7 values that have been generated using the suggested mutual correlation equation and the observed data.
This investigation was carried out to estimate the antiparasitic potential of silver and Chitosan nanoparticles loaded with spiramycin against toxoplasmosis infected. After mice injected intraperitoneal in a dose 103viable tachyzoites for acute infection; then treated with spiramycin, chitosan nanoparticles and silver nanoparticles as a single or combined therapy given for seven days. Peritoneal fluid examination revealed a significant decrease in the number of