Back ground: Several devices with different physical bases have been developed for the clinical measurement of corneal thickness, they classified into 4 categories: Scheimpflug photography based, Slit –Scanning topography, optical coherence tomography (OCT) based and ultrasound (US) based.Objective:To evaluatethe precision of the new Scheimpflug –Placido disc corneal topography in measurement of corneal thickness and to compare the measured values with that obtained by US pachymetry.Methods: Setting of this study is Lasik center in Eye Specialty Private Hospital. Baghdad. Iraq.Eyes of healthy subjects were examined with the Sirius topography.3 consecutive measurements of central (CCT)and thinnest (TCT) corneal thicknesses were obtainedand the measurements repeated within 1 week. The within –subject standard deviation (Sw),test-retest repeatability ,coefficient of variation (CoV),and interclass correlation coefficient (ICC) were calculated to evaluate intra session repeatability and intersession reproducibility. For US pachymetry (Tomey-SP 100) only CCT was measured. Comparison ofthe measurements that obtained by the 2 devices done by paired t-test.Results: The topography provides high intrasession repeatability with test-retest and CoV close to 6μm and0.4%, respectively for both CCT and TCT. The inter session reproducibility also high with test-retest and CoV close to 8μm and 0.5%, respectively.ICC was higher than 0.97 for repeatability and reproducibility . Anarrow 95% limit of agreement was found between the pachymetry obtained by topography and US pachymetry measurements.Conclusions :The topography has been used showed high intrasession repeatability and intersession reproducibility of CCT and TCT measurements in healthy eyes .Absence of statistically significant differences suggest that the topography -TCT and the US pachymetry - CCT can be used interchangeably in subject with normal cornea.Financial Disclosure: No financial or proprietary interest in any material or method mentioned.
This work presents a design for a pressure swing adsorption process (PSA) to separate oxygen from air with approximately 95% purity, suitable for different numbers of columns and arrangements. The product refill PSA process was found to perform 33% better (weight of zeolite required or productivity) than the pressure equalization process. The design is based on the adsorption equilibrium of a binary mixture of O2 and N2 for two of the most commonly used adsorbents, 5A & 13X, and extension from a single column approach. Zeolite 13X was found to perform 6% better than zeolite 5A. The most effective variables were determined to be the adsorption step time and the operational pressure. Increasing the adsorption step
... Show MoreLow salinity (LS) water flooding is a promising EOR method which has been examined by many experimental studies and field pilots for a variety of reservoirs and oils. This paper investigates applying LS flooding to a heavy oil. Increasing the LS water temperature improves heavy oil recovery by achieving higher sweep efficiency and improving oil mobility by lowering its viscosity. Steam flooding projects have reported many problems such as steam gravity override, but override can be lessened if the steam is is alternated with hot LS water. In this study, a series of reservoir sandstone cores were obtained from Bartlesville Sandstone (in Eastern Kansas) and aged with heavy crude oil (from the same reservoir) at 95°C for 45 days. Five reservo
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Background: Dialysis is in common use to treat patients
with end stage renal failure .However longstanding dialysis
harboring some cellular changes in various body fluids.
This study was conducted in order to detect these changes
in urine.
Objective: The study was conducted to detect cellular
changes in urine of patients with longstanding dialysis.
Method: Fifty-three urine samples were examined
cytologically obtained from patients with longstanding
dialysis during 6 months period. Freshly voided midstream
urine samples were taken . Samples were centrifuged and 2
to 3 drops of sediments were smeared on 2 glass slides and
fixed in 95% ethyl alcohol then stained with Hand E stain
to be evaluated.
R
The non static chain is always the problem of static analysis so that explained some of theoretical work, the properties of statistical regression analysis to lose when using strings in statistic and gives the slope of an imaginary relation under consideration. chain is not static can become static by adding variable time to the multivariate analysis the factors to remove the general trend as well as variable placebo seasons to remove the effect of seasonal .convert the data to form exponential or logarithmic , in addition to using the difference repeated d is said in this case it integrated class d. Where the research contained in the theoretical side in parts in the first part the research methodology ha
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In this paper, simulation studies and applications of the New Weibull-Inverse Lomax (NWIL) distribution were presented. In the simulation studies, different sample sizes ranging from 30, 50, 100, 200, 300, to 500 were considered. Also, 1,000 replications were considered for the experiment. NWIL is a fat tail distribution. Higher moments are not easily derived except with some approximations. However, the estimates have higher precisions with low variances. Finally, the usefulness of the NWIL distribution was illustrated by fitting two data sets
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In this paper, a discretization of a three-dimensional fractional-order prey-predator model has been investigated with Holling type III functional response. All its fixed points are determined; also, their local stability is investigated. We extend the discretized system to an optimal control problem to get the optimal harvesting amount. For this, the discrete-time Pontryagin’s maximum principle is used. Finally, numerical simulation results are given to confirm the theoretical outputs as well as to solve the optimality problem.
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In this paper, new concepts which are called: left derivations and generalized left derivations in nearrings have been defined. Furthermore, the commutativity of the 3-prime near-ring which involves some
algebraic identities on generalized left derivation has been studied.
In this paper we generalize some of the results due to Bell and Mason on a near-ring N admitting a derivation D , and we will show that the body of evidence on prime near-rings with derivations have the behavior of the ring. Our purpose in this work is to explore further this ring like behavior. Also, we show that under appropriate additional hypothesis a near-ring must be a commutative ring.
Background: Laparoscopic surgery for
appendicitis is now a well established and
advanced method of performing general surgical
procedures.
Objectives: To compare the outcome of
laparoscopic and open appendectomies in terms
of operative time, analgesic requirement,
postoperative complications, hospital stay, return
to normal activity and condition of scar.
Methods: This prospective study was carried
out from 1stMay 2008-1st January 2010, involving
110 patients (45 male and 65 female) with
features suggestive of acute appendicitis were
divided into 45 patients laparoscopic
appendectomy (LA) group and 65 patients open
appendectomy (OA) group, after taking informed
consent. LA was done with the