Ali Amiri

Determination of Doxepin in human plasma using cloud‐point extraction with high‐performance liquid chromatography and ultraviolet detection

A new straightforward method based on cloud-point extraction has been developed, optimized, and validated for the determination of doxepin in human plasma by high-performance liquid chromatography separation and UV detection. The nonionic surfactant Triton X-114 was chosen as the extraction solvent. Chromatography separation was performed on a μBondapakR C18 column (4.6 mm id × 300 mm, 3 μm particle size), which was used for isocratic elution at a detection wavelength of 289 nm. Under the optimum conditions, the linear range of doxepin in human plasma was 0.1-0.9 μg/mL. Also, the detection limit, preconcentration factor, and enrichment factor were 0.08 μg/mL, 50, and 49.0, respectively.

Stable isotope (O and C) geochemistry of non-sulfide Zn–Pb deposits; case study: Chah-Talkh non-sulfide Zn–Pb deposit (Sirjan, south of Iran)

The study of oxygen and carbon isotopic ratios has gained importance to determine the origin of ore-bearing fluids, carbon origin, and also to determine the formation temperature of non-sulfide Pb and Zn minerals. In order to determine the origin of fluids and carbon existing in Zn carbonate minerals in Chah-Talkh deposit, initially the amounts of δ18OSMOW and δ13CPDB changes in various zinc minerals in important deposits in Iran and the world were studied, and then by comparing these values in Chah-Talkh deposit with those of other deposits, the origin of fluids responsible for ore forming, carbon, and formation temperature of Chah-Talkh deposit was determined. The range of δ18OSMOW changes in smithsonite mineral in non-sulfide lead and zinc deposits varies from 18.3 to 31.6 ‰, and δ18OSMOW in hydrozincite mineral varies from 7.8 to 27 ‰. Due to the impossibility of smithsonite sampling from Chah-Talkh deposit (due to it being fine-grained and dispersed), hydrozincite minerals which have high isotopic similarities with smithsonite are used for the isotopic analysis of carbon and oxygen. The range of δ18OSMOW changes in hydrozincite mineral of Chah-Talkh deposit varies from 7.8 to 15.15 ‰, which places in the domain of metamorphic water. The extensiveness of δ18OSMOW changes in Chah-Talkh indicates the role of at least two fluids in the formation of non-sulfide minerals. The obtained formation temperature of non-sulfide minerals (hydrozincite) in Chah-Talkh deposit is 70 to 100xa0°C, which indicates the role of metamorphic fluids in the formation of deposit. Complete weathering of sulfide minerals to a depth of 134xa0m confirms the role of rising metamorphic fluids in the formation of non-sulfide minerals. The δ13CPDB values of Chah-Talkh deposit are set in the range of atmospheric CO2 and carbonate rocks, in which the existence of atmospheric CO2 indicates the role of atmospheric fluids, and the existence of carbonate carbon rock indicates of the role of metamorphic fluids in the precipitation of non-sulfide Zn minerals.

The protective effects of erythropoietin on photoreceptor damage by formaldehyde

INTRODUCTIONnThe photoreceptor layer of retina has important role for sight. The previous study showed that accidental formaldehyde injection caused ischemia and damage in the retina. On the other hand the erythropoietin prevents neuronal injury of ischemic damage.nnnOBJECTIVESnThe aim of this study was to survey the effect of erythropoietin on retro bulbar formaldehyde injected photoreceptor layer of rat retina.nnnMATERIALS AND METHODSn30 adult rats were used and divided into three groups: 1- control group, 2- formaldehyde group (1 ml retro bulbar injected by 10% formaldehyde solution), 3- erythropoietin group (5000 units/kg immediately intraperitoneally injected by erythropoietin after formaldehyde injection for 7 days). The photoreceptor layer of retina studied using a transmission electron microscope.nnnRESULTSnOur observation showed that disorganization and vacuolization in outer segment and inner segment, pyknotic and karyolysis in outer nuclear layer were seen in formaldehyde group. But the minor sign of pathology such as lightly vacuolization in inner segment were obvious in erythropoietin group.nnnCONCLUSIONnWe concluded that formaldehyde caused damage in photoreceptor layer and erythropoietin was improvement this injury.

Investigate The Relationship Between Cost Management Strategy, Organization Size, Growth Options and The Performance Of Companies In Tehran Stock Exchange

This study aimed to investigate the relationship between cost management strategy, organization size and growth Options on the performance of the company. In this regard, the financial statements of 76 companies listed in Tehran Stock Exchange for the years 2009 to 2013 were analyzed. In this study, cost management strategy (the ratio of capital expenditure to sales, sales of the book value of fixed assets) and size (natural logarithm of total assets) and growth Options (market value of assets to book value of assets) as a variable. independent, and firm performance (return on assets, sales growth) was used as the dependent variable, so that the relationship between strategy, size, growth Options and firm performance during a 5-year period studied. The method used for data collection, library and field. To test the hypotheses of the model Autoregressive conditional heteroscedasticity (ARCH) and generalized regression model, the conditional heteroscedasticity (GARCH) were analyzed using the software Eviews8. And significance was determined using a Z score and likelihood ratio. The criteria for the variable sales strategy to sell the book value of fixed assets and the capital expenditure of a significant and positive relationship with sales growth. In the capital, Tehran Stock Exchange Market participants are recommended to consider it as the time-varying volatility and time efficiencies associated with corporate assets can be public relations strategy, cost management and growth Options of the company described. Also associated with the companys sales growth can be described by the relationship between the size and cost management strategy

Uncertainty assessment in access control of pervasive computing environments

One of the important risk factors in pervasive computing environments is uncertainty. The cause of this uncertainty, changes in user mobility or transport user. In general, uncertainty in pervasive computing environments occurs in two cases: uncertainty in sensors and uncertainty in sensor information combination. Error in the verification and misunderstanding can be caused to fall risk pervasive computing applications security, power, efficiency and performance. In fact, access control in this environment is dependent on the evaluation of sensors and information received from them. In other words, if the information is correct, that is received through the sensors, can have access control with high reliability.

Partial and Random Updating Weights in Error Back Propagation Algorithm

One of the introduce discussions in the field of using MLPNN, as a tools for data classification is related to the error back propagation algorithm which use to train the network. It has challenges for large-scale and heterogeneous data such as, lack of memory and low–speed convergence, besides, computational load is high. In this paper proposed method with partial and random updating some of weights instead of all of them in each iteration, cause to decrease computational rate, improve lack of memory’s problem and somewhat increase convergence speed. Result of experiments on two standard dataset, demonstrate efficiency of algorithm.