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"n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: According to importance of post operative period, admission duration, post operative pain, and acceptable rate of complications, minimally invasive approaches with endoscope in pancreatic pseudocyst management becomes more popular, but the best choice of procedure and patient selection is currently not completely established. During past decade endoscopic procedures are become first choice in most authors' therapeutic plans, however, open surgery remains gold standard in pancreatic pseudocyst treatment."n"nMethods: we present here a patient with pancreatic pseudocyst unresponsive to conservative management that is intervened endoscopically before 6th week, and review current literatures to depict a schema to management navigation."n"nResults: A 16 year old male patient presented with two episodes of acute pancreatitis with abdominal pain, nausea and vomiting. Hyperamilasemia, pancreatic ascites and a pseudocyst were found in our preliminary investigation. Despite optimal conservative management, including NPO (nil per os) and total parentral nutrition, after four weeks, clinical and para-clinical findings deteriorated. Therefore, ERCP and trans-papillary cannulation with placement of 7Fr stent was performed and led to a dramatic improvement."n"nConclusions: Endoscopic based approaches must be considered the first line intervention for pseudocyst management and its complications. Complexity and need for technical expertise for endoscopic therapy is rate limiting issue for this approach. Surgical intervention must be reserved for unresponsive patients to minimally invasive treatments. Further investigations need for more complex endoscopic procedures that promote the results.

Introduction: The aim of this study was to evaluate the expression of pinopodes as animplantation marker after ovarian hyper stimulation and progesterone injection using scanningelectron microscopic studies. Material and Methods: Three groups of NMRI adult female mice were used in the experiment. The control group (Group A) were untreated pseudopregnant mice. Group B mice were made pseudopregnant after super ovulation treatment with hMG and hCG. Group C micewere treated the same as Group B and then received progesterone daily from day 1 of pseudopregnancy. Animals were sacrificed by cervical dislocation 3.5 and 4.5 days after hCG injection. Tissues were obtained from the middle 1/3 part of uterine horns and processed for scanning electron microscopic studies. Results: In the control group there were some pinopodes at 3.5 days of pseudopregnancy and the apical surface of all cells expressed these projections on day four. In the hyperstimulated group without progesterone injection no pinopodes were seen 3.5 days after hCG injection and some appeared on day 4. In the hyper stimulated and progesterone-injected group well developed pinopodes were expressed 3.5 days after stimulation and they became much smaller on day 4 after hCG injection. Conclusion: The results showed that the life span of pinopodes is short and changeable during hyper stimulation and that progesterone causes premature expression of the pinopodes, suggesting that the implantation after ovarian stimulation might depend upon the timing of the pinopode expression.

Independence test based on empirical copula does not perform well in the presence of weak dependency or when dependency occurs only in the tails. The copula density, which is estimated by a local likelihood probit transformation method, is used to detect the independence. In this article, three nonparametric tests of independence based on α-divergence and copula density are introduced. These tests are capable of considering weak dependency. The asymptotic consistency of the copula-based α-divergence estimator is also derived. In addition, the empirical powers of the proposed tests are computed through extensive simulations. The results show that the new tests outperform in small sample sizes or weak dependencies. Finally, an application in uranium exploration is presented to illustrate the applicability of the proposed tests. [ABSTRACT FROM AUTHOR]

Only representative samples could represent original reservoir conditions and have prevented overdesigning surface facilities and have been requirements of reservoir management programs. Representative samples cannot be collected in unsteady state situations. In some cases, samples must be collected in this state, so non-representative samples are obtained. Gas coning is one of the parameters that makes unsteady state flows. There is no standard method to determine accurate original compositions from non-representative samples. In this article, an attempt is made to introduce an accurate method for obtaining original in situ compositions from gas coning wells. Four Iranian oil reservoir samples obtained from the pressure volume temperature laboratory are used for evaluating methods of obtaining original fluids in unsteady state situations for the first time. For this purpose a synthetic model is formed by compositional simulation, and fluid properties of each reservoir are imported to it. Separator sampling is performed in the model. Methods of synthesizing original compositions (recombination and equilibrium contact mixing) are modeled by detailed equation of state characterization in the new scheme. Then collected samples are imported to them. Comparisons are made on obtained results of recombination and equilibrium contact mixing methods to find the most accurate method. It is concluded that equilibrium contact mixing, which was uncertain for companies, is definitely the most accurate method. Also, the authors conclude that after more than 2 years production performing an equilibrium contact mixing method is impossible in volatile oil models with gas coning but recombination with low accuracy can be used; however, equilibrium contact mixing has no limitation in black oil systems with gas coning and has minimum errors. [ABSTRACT FROM PUBLISHER]

Low-swirl burners are of interest in industrial applications due to their low NO x emissions. In the present work, a 3.81 cm diameter low-swirl burner is acoustically forced with different fuel mixtures. The measured results are compared to 2.54 cm diameter low-swirl burner data to infer scaling properties. The experiments and analysis show that three coupling modes were present in the 3.81 cm burner: base mode coupling, shear layer generated coupling, and transitional coupling. The 3.81 cm burner was observed to have a critical acoustic driving pressure amplitude, similar to the 2.54 cm burner; however, the 3.81 cm burner had higher frequency natural acoustic modes. This counter-intuitive result is shown to arise because the modes are tied to shear layer behavior rather than burner size. It was also observed that adding hydrogen to the fuel stream resulted in less coherence. This is likely the result of increased flame speed and decreased ignition limit, allowing the flame to interact less with both large and small vortices. Small scale interaction leads to more small scale wrinkling while strong large scale vortices produce more flame role up and displacement of heat release zones. The ability of hydrogen addition to negate these effects suggests selective hydrogen addition as a possible method of inhibiting combustion instability. [ABSTRACT FROM AUTHOR]

Equivariant functions can be useful for constructing of maximal invariant statistic. In this article, we discuss construction of maximal invariants based on a given weakly equivariant function under some additional conditions. The theory easily extends to the case of two or more weakly equivariant functions. Also, we derive a maximal invariant statistic when the group contains a sharply transitive and a characteristic subgroup. Finally, we consider the independence of invariant and weakly equivariant functions under some special conditions. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the effects of supplemented curcumin (CMN), derived from plant Curcuma longa, extract on performance and blood parameters of acetaminophen (ACT) induced quail hepatic injury. 240 quails from 0-37 days of age were used in a completely randomized design with 4 treatments of 4 replicates each and 15 chickens per replicate. All groups received 750 mg/kg body weight oral doses of ACT at 12 days of age. Japanese quails were divided into four groups: control (no CMN), commercial diet with 20 g CMN per ton, commercial diet with 40 g CMN per ton and commercial diet with 60 g CMN per ton. Feed intake and body weight gain were recorded weekly. Blood albumin, glucose, total protein, triglyceride, aspartate aminotransferase, alanine aminotransferase, bilirubin, uric acid and creatinine were determined at 28 and 35 days of age. Adding curcumin to the diets significantly increased serum aspartate aminotransferase at 28 days of age (P<0.05) and decreased triglyceride and bilirubin at 35 days of age (P<0.05). There were no significant differences in performance and other blood parameters among the treatment groups at 28 and 35 days of age. The data indicated that curcumin is a natural antioxidant hepatoprotective agent against hepatotoxicity induced by acetaminophen model. Thus, curcumin may have a therapeutic value in drug-induced hepatotoxicity as well as in acetaminophen therapy. [ABSTRACT FROM AUTHOR]

Foamy oil expression has puzzled many reservoir engineers in characterizing some heavy oil reservoirs. The strange fluid behavior of such reservoirs is considered as the reason of abnormally high flow rates and (the higher than expected) recovery factors. The authors aimed to briefly elaborate the foamy oil concept, review methodologies and laboratory experiments for identifying foamy oil behavior, and present a modified methodology for laboratory investigation of foamy behavior. The concern here is an Iranian heavy oil reservoir whose foamy nature is under debate (according to some production reports). Experimental results indicate that the studied crude oil acquires foamy characteristics, which makes it the first heavy oil reservoir with foamy behavior in the Middle East region. [ABSTRACT FROM PUBLISHER]

Screening analysis is a useful guideline that helps us with proper field selection for different enhanced oil recovery processes. In this work, reservoir simulation is combined with experimental design to estimate the effect of reservoir rock and fluid properties on performance of immiscible nitrogen injection. Reservoir dip, thickness, and horizontal permeability are found to be the most influential parameters. Possible interactions of parameters are also discussed to increase reliability and robustness of screening results. Finally, significance of both main effects and interactions are evaluated by employing a statistical inference approach (hypothesis testing) and results are compared to Pareto analysis. [ABSTRACT FROM PUBLISHER]

This article aims at the image processing of surface uniformity and thermally bonded points uniformity in polypropylene spunbonded non-wovens. The investigated samples were at two different weights and three levels of non-uniformity. An image processing method based on the k-means clustering algorithm was applied to produce clustered images. The best clustering procedure was selected by using the lowest Davies-Bouldin index. The peak signal-to-noise ratio (PSNR) image quality evaluation method was used to choose the best binary image. Then, the non-woven surface uniformity was calculated using the quadrant method. The uniformity of thermally bonded points was calculated through an image processing method based on morphological operators. The relationships between the numerical outcomes and the empirical results of tensile tests were investigated. The results of image processing and tensile behavior showed that the surface uniformity and the uniformity of thermally bonded points have great impacts on tensile properties at the selected weights and non-uniformity levels. Thus, a sample with a higher level of uniformity and, consequently, more regular bonding points with further bonding percentage depicts the best tensile properties.

In some practical inferential situations, it is needed to mix some finite sort of distributions to fit an adequate model for multi-modal observations. In this article, using evidential analysis, we determine the sample size for supporting hypotheses about the mixture proportion and homogeneity. An Expectation-Maximization algorithm is used to evaluate the probability of strong misleading evidence based on modified likelihood ratio as a measure of support. [ABSTRACT FROM AUTHOR]

For direction of arrival (DOA) estimation in compact arrays, a new approach based on time delay and amplitude estimation is presented for a known signal. The DOA can be accurately estimated without any calibration sources since the mutual coupling and multipath effects can be eliminated by the inherent mechanism of the proposed algorithm. The algorithm has significantly lower error and much less computational burden compared with the previous methods in high signal-to-noise ratio (SNR) conditions. [ABSTRACT FROM AUTHOR]

In this study, the authors perform a complete survey on S-parameter method applications to compensate the coupling effect in circular arrays. The authors illustrate that, despite the simplicity and ease of measurements, the S-parameter algorithm has an adequate performance in comparison with the external calibration techniques in real environments. Based on the simulation and experimental results, for unmatched arrays and low-frequency applications [e.g. high-frequency (HF) radars], the S-parameter method performance is demonstrated to be comparable in accuracy to the external calibration techniques. Despite multipath effect and structural scattering, the direction of arrival can be estimated by the S-parameter method with the same accuracy as obtained by the external calibration techniques, which are disadvantageously location dependent. [ABSTRACT FROM AUTHOR]

To explore the effects of the combination of tryptophan (Trp) and arginine (Arg) on growth performance, serum parameters and immune response of broiler chickens challenged with intermediate plus strain of infectious bursal disease virus vaccine, an in vivo experiment was conducted. A corn-soybean meal-based diet containing different levels of Arg and Trp was used. Cobb500 male broiler chickens from 0 to 49 days of age were subjected to a diet supplemented with the combination of Trp and Arg. Growth performance parameters and serum parameters were measured at 27 and 49 days of age. To evaluate the immunomodulatory effects of the combination of Trp and Arg on the challenged chickens, we measured the serum levels of interferon-α, interferon-γ and immunoglobulin G at 27, 35, 42, and 49 days of age. The results showed that the three evaluated immune system parameters including interferon-α, interferon-γ and immunoglobulin G were significantly enhanced after treatment. This enhancement resulted in the recovery of infectious bursal disease virus-infected chickens compared with controls as confirmed by histopathological examinations. Moreover, serum parameters such as albumin and total protein increased, whereas the treatment decreased (P<0.05) the feed:gain ratio, aspartate amino-transferase, alkaline phosphatase, lactic dehydrogenase, triglyceride and cholesterol. These findings suggest that the combination of Arg and Trp has a regulatory effect on growth performance. Moreover, it modulates the systemic immune response against infectious bursal disease. [ABSTRACT FROM AUTHOR]

Abstract: The accurate prediction of diffusion coefficients of methane in liquid hydrocarbons is one of the key parameters for improving the prediction of compositional oil reservoir simulators, for designing surface facilities, and for high pressure gas/liquid mass transfer operations. In this investigation, a precision high pressure and temperature diffusion cell apparatus has been used to measure diffusion coefficients of methane in dodecane and in a typical Iranian crude oil at high pressures and temperatures. The diffusion cell is modelled using a finite-domain moving boundary method. Extensive experimental results are presented at high pressures and temperatures, especially for regions where published data were insufficient. The mechanism of mass transfer during the incubation period is analysed by solving the equation of continuity for the diffusion cell numerically and considering that the diffusion coefficient is changing with time and concentration. The effects of pressure, liquid phase viscosity and operating temperature on the diffusion coefficient of the solute gas in the solution are discussed. The results indicate that uncertainties which generally exist in the physical and thermodynamic properties of the crude oils may have a significant effect on the diffusion coefficient of a solute gas in a complex mixture like crude oil. [Copyright &y& Elsevier]

A simple kinetic spectrophotometric method for the determination of oxalic acid has been described, based on its catalytic effect on the oxidation of pyrocathecol violet (PCV) with potassium dichromate in acidic media. The reaction was monitored photometrically by measuring the decrease in absorbance of PCV at 450 nm. The influence of acid, PCV concentration, dichromate concentration, and temperature were studied and optimized completely. Under the optimum condition, a calibration graph from 0.08 to 1.3 µg/mL of oxalic acid with a detection limit of 0.07 µg/mL was obtained. The relative standard deviation for ten replicate measurement of 0.8 µg/mL oxalic acid is 0.8%. The proposed method is fast and simple. The applicability of the method was demonstrated by the determination of oxalic acid in wastewater, spinach, and mushroom samples. [ABSTRACT FROM AUTHOR]

In traditional material balance calculations, shut-in well pressure data are used to determine average reservoir pressure while recent techniques do not require the well to be shut-in and use instead flowing well pressure-rate data. These methods, which are known as “dynamic” material balance, are developed for single-phase flow (oil or gas) in reservoirs. However, utilization of such methods for gas-condensate reservoirs may create significant errors in prediction of average reservoir pressure due to violation of the single-phase assumption in such reservoirs. In a previous work, a method for production data analysis in gas-condensate reservoirs was developed. The method required standard gas production rate, producing gas-oil ratio, flowing well pressure, CVD data and relative permeability curves. This paper presents a new technique which does not need relative permeability curves and flowing well pressure. In this method, the producing oil-gas ratio is interpolated in the vaporized oil in gas phase (Rv) versus pressure (p) data in the CVD table and the corresponding pressure is located. The parameter pressure/two-phase deviation factor (p/ztp) is then evaluated at the determined pressure points and is plotted versus produced moles (np) which forms a straight line. The nature of this plot is such that its extrapolation to point where p/ztp = 0 will give initial moles in place. Putting initial pressure/initial two-phase deviation factor (pi/ztp,i) (known parameter) and estimated initial moles (ni) into the material balance equation, average reservoir pressure can be determined. A main assumption behind the method is that the region where both gas and condensate phases are mobile is of negligible size compared to the reservoir. The approach is quite simple and calculations are much easier than the previous work. It provides a practical engineering tool for industry studies as it requires data which are generally available in normal production operations. However, it is only applicable when average reservoir pressure approaches dew point pressure and falls below it. The methodology is validated using synthetic production data for several examples. In addition, the method is evaluated through estimation of average reservoir pressure and original gas in place from actual field data. The results show a fairly good agreement in gas in place obtained from the new method and that of volumetrically calculated value for this field.

The majority of oilfields, especially those under water injection suffer from scale deposition. The common method of addressing the scale issue is to deploy the integrated scale risk management, by which the data from all available disciplines such as Chemistry, Field Engineering, Completion Engineering, etc. are integrated to make the most suitable decision. The main aim of this study is to perform integrated scale risk management in the A carbonate oil field, under water injection. Several experimental, field and simulation studies were done to investigate the main causes of scales. Produced waters were sampled and analyzed every three months to follow their compositional variations. Comprehensive atmospheric and core flood tests were carried out to assess the impact of deposited scales. Moreover, several real samples of scales were sampled and analyzed. Since the reservoir rock is carbonate type, the emphasis must be on the associated challenges such as rock-fluid interaction and fluid flow. Several simulators including finite difference, streamline, and reaction simulators (CMG-GEM GHG) were used to study the scales and the communication between wells. Integrating the results, a comprehensive workflow was designed for the continuation of this study and analog fields. The main sources of scales, their types and severity through the reservoir were evaluated and reactive and proactive approaches were suggested to reduce or eliminate the scale risks. Furthermore, this study shows that a proper design of inhibitor placement by coil would result in satisfactory placement for all wells, and fluid-rock interaction raises the severity of Calcite deposition. [ABSTRACT FROM AUTHOR]