The use of fuzzy real option valuation method to rank Giga Investment Projects on Iran's natural gas reserves

Giga investments are exposed to numerous systematic and unsystematic (or specific) risks that significantly influence their feasibility and value. In addition to the conventional issues and complexities in evaluating investment projects, factors such as long construction time, high amount of capital required and irreversibility of investment, increase uncertainty of cash flows in these types of projects. As a consequence, decision makers are usually not satisfied with the results of the most popular valuation methodology – discounted cash flow analysis – in valuation of Giga investments. The most promising methodology of valuing flexibility in such investment projects is the real options valuation which quantifies the value of embedded flexibilities through option pricing techniques.In this paper, fuzzy real options valuation techniques are used to rank Giga project proposals faced in Iran's gas industry. To this end, different scenarios of project payoff and future uncertainties are quantified, using fuzzy numbers based on findings from earlier real option valuation methods.Keywords: Giga Investment, Fuzzy Pay Off, Real options valuation, Natural Gas, Ira

In Vitro and in Vivo Enhancement of Antitumoral Activity of Liposomal Antisense Oligonucleotides by Cineole as a Chemical Penetration Enhancer

Cellular uptake and cytoplasmic release of liposomal antisense oligonucleotides (AsODNs), which can act as rate-limiting steps, are still remained to be completely optimized. Here, the possibility of enhancing such processes at cellular and animal levels by cineole, as a penetration enhancer, was investigated. A cationic nanoliposome containing an AsODN against PKC-α and a cineole-containing nanoliposome were prepared and characterized. The effect of nanoliposomal cineole on sequence-specific cytotoxicity of nanoliposomal AsODN against A549, was studied in vitro (MTT, flow cytometry, fluorescence microscopy, and real time PCR) and in vivo (xenograft lung tumor in nude mice) using different concentrations and treatment times. Results showed specific cytotoxicity of nanoliposomal AsODN was increased significantly from 11 to 25 when A549 cells were exposed to 10 μg/mL cineole for 1 or 4 hours. This inhibitory effect was further increased to about 40 when the concentration was increased to 40 μg/mL for 1 hour. In animal studies, cineole significantly decreased the tumor volume (about 75) and increased its doubling time from 13 days to 31 days. A linear relationship exists between cineole concentration and its enhancement effects. Finally it was concluded that cineole, and possibly other membrane fluidizers, can improve nanoliposomal gene therapy at cellular and animal levels. © 2015 Hamid Reza Moghimi et al

The influence of using different reconstruction algorithms on sensitivity of quantitative 18F-FDG-PET volumetric measures to background activity variation

Introduction: This study aims to investigate the influence of background activity variation on image quantification in differently reconstructed PET/CT images. Methods: Measurements were performed on a Discovery-690 PET/CT scanner using a custom-built NEMA-like phantom. A background activity level of 5.3 and 2.6 kBq/ml 18F-FDG were applied. Images were reconstructed employing four different reconstruction algorithms: HD (OSEM with no PSF or TOF), PSF only, TOF only, and TOFPSF, with Gaussian filters of 3 and 6.4 mm in FWHM. SUVmax and SUVpeak were obtained and used as cut-off thresholding; Metabolic Tumor Volume (MTV) and Total Lesion Glycolysis (TLG) were measured. The volume recovery coefficients (VRCs), the relative percent error (�MTV), and Dice similarity coefficient were assessed with respect to true values. Results: SUVmax and SUVpeak decreased and MTV increased as function of increasing the background dose. The most differences occur in smaller volumes with 3-mm filter; Non-TOF and Non-PSF reconstruction methods were more sensitive to increasing the background activity in the smaller and larger volumes, respectively. The TLG values were affected in the small lesions (decrease up to 12). In a range of target volumes, differences between the mean �MTV in the high and low background dose varied from -11.8 to 7.2 using SUVmax and from 2.1 to 7.6 using SUVpeak inter reconstruction methods. Conclusion: The effect of the background activity variation on SUV-based quantification in small lesion was more noticeable than large lesion. The HD and TOFPSF algorithms had the lowest and the highest sensitivity to background activity, respectively. © 2018 Iranian Journal of Nuclear Medicine. All Rights Reserved

Assessment of different MCNP Monte Carlo codes in electron absorbed dose

BackgroundMCNP is a general-purpose Monte Carlo code for simulation of neutrons, photons and electrons or coupled neutron/photon/electron transport. This code is based on ETRAN/ITS codes. There are different versions of this code.AimThis work aims to compare the more recently released MCNP codes with the earlier version in terms of the central axis absorbed dose (CADD), the energy spectrum and the computational efficiency. MCNP codes 4A, 4B, 4C, X and 5 were compared for a 10 MeV electron beam in water.Materials/MethodsThe energy spectra of electrons were scored on the phantom surface and planes 3 and 5cm deep using F2 tally subdivided into 0.1 MeV energy bins. This tally also was repeated for 4A, 4B, 4C and X with smaller energy bins (0.05 MeV). The simulated geometry and other input parameters were kept the same. Both the default and ITS energy indexing algorithms (EIA) were used in 4B, 4C and X, while only the default EIA was employed in 4A and 5.ResultsWith default indexing, X and 5 showed no difference in CADD compared to 4B and 4C and were within 3% of 4A. We found no differences in CADD between codes when 4B, 4C and X were used with ITS indexing. The ITS algorithm improved computational efficiency. For the energy spectrum at the phantom surface, all codes except X show very similar results (within 2%). However, changing the energy indexing to ITS as well as using a 0.05 MeV bin removed this discrepancy at the surface for X code.ConclusionsWhile, under the examined conditions, versions 4B and later behaved similarly in terms of the resulting CADD, the ITS indexing should be used due to its agreement with measurements and computational efficiency

Monte Carlo study of electron dose distributions produced by the elekta precise linear accelerator

BackgroundMonte Carlo simulation of radiation transport is considered to be one of the most accurate methods of radiation therapy dose calculation and has ability to reduce the uncertainty in the calculated dose to a few percent.Aims(1) To study the efficacy of the MCNP4C Monte Carlo code to simulate the dose distribution in a homogeneous medium produced by electron beams from the Elekta Precise linear accelerator. (2) To quantify the effect of introduction of various components to the simulated geometry for the above machine.Materials/MethodsFull Monte Carlo simulation of the detailed geometry of the Precise treatment head for 8 and 15 MeV energies and 10×10 applicator was performed. Experimental depth dose and lateral profiles at 2cm depth were measured using a P-type diode detector with a 2.5 mm diameter. To quantify the effects of different parts of the treatment head, seven cases were simulated for a 15 MeV beam to reflect increasing levels of complexity, by step-wise introduction of beam divergence, primary and secondary scattering foils, secondary collimators, applicator, Mirror and Mylar screen.ResultsThe discrepancy between measured and calculated data is within 2%/2 mm at both 8 and 15 MeV. In terms of the mean and most probable energies at the surface, the difference wa

Efficacy of compound therapy by ginseng and ciprofloxacin on bacterial prostatitis

Objective: Genitourinary tract infections play a significant role in male infertility. Infections of reproductive sex glands, such as the prostate, impair function and indirectly affect male fertility. The general aim of this study is to investigate the protective effect of Korean red ginseng (KRG) on prostatitis in male rats treated with ciprofloxacin (CIPX). Materials and Methods: In this experimental study, we randomly divided 72 two male Wistar rats into 9 groups. The groups were treated as follows for 10 days: i. Control (no medication), ii. Sham (normal saline injection into the vas deferens and oral administration of phosphate-buffered saline (PBS), iii. Ginseng, iv. CPIX, v. CIPX+ginseng, vi. Uropathogenic Escherichia coli (E. coli) (UPEC), vii. UPEC+ginseng, viii. UPEC+CIPX, and ix. UPEC+ginseng+CIPX. The rats were killed 14 days after the last injection and the prostate glands were removed. After sample preparation, routine histology was performed using hematoxylin and eosin staining. The terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL) method was used to determine the presence of apoptotic cells. Results: The severity score for acinar changes and inflammatory cell infiltration in the UPEC+CIPX group did not significantly different from the UPEC group. However this score significantly decreased in the UPEC+CIPX+ginseng group compared to the UPEC group. Apoptotic index of all ginseng treated groups significantly decreased compared to the UPEC and CPIX groups. Conclusion: These results suggested that ginseng might be an effective adjunct in CIPX treatment of prostatitis. The combined use ginseng and CIPX was more effective than ginseng or CIPX alone

Testing Logselfsimilarity of Soil Particle Size Distribution: Simulation with Minimum Inputs

Particle size distribution (PSD) greatly influences other soil physical properties. A detailed textural analysis is time-consuming and expensive. Soil texture is commonly reported in terms of mass percentages of a small number of size fractions (typically, clay, silt and sand). A method to simulate the PSD from such a poor description or even from the poorest description, consisting in the mass percentages of only two soil size fractions, would be extremly useful for prediction purposes. The goal of this paper is to simulate soil PSDs from the minimum number of inputs, i.e., two and three textural fraction contents, by using a logselfsimilar model and an iterated function system constructed with these data. High quality data on 171 soils are used. Additionally, the characterization of soil texture by entropy-based parameters provided by the model is tested. Results indicate that the logselfsimilar model may be a useful tool to simulate PSD for the construction of pedotransfer functions related to other soil properties when textural information is limited to moderate textural data

Breast cancer cells imaging by targeting methionine transporters with gadolinium-based nanoprobe

Purpose: Early cancer diagnosis using MRI imaging is of high global interest as a non-invasive and powerful modality. In this study, methionine was conjugated on gadolinium-based mesoporous silica nanospheres to evaluate intra-cellular uptake and its accumulation in human breast cancer cells. Procedures: The contrast agent was synthesized and characterized using different techniques including N2 physisorption, thermal gravimetric analysis, dynamic light scattering, and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The intra-cellular uptake of Gd3+ was measured by ICP-AES, fluorescent microscopy, and flow cytometry. Finally, cellular and tumor MR imaging were performed to determine in vitro and in vivo relaxometry. Results: According to the results, the contrast agents accumulated in tumor cells both in vitro and in vivo. There was no significant cellular toxicity on either normal or cancer cells along with strong intense signal on T1 compared to the unlabeled cells. Conclusions: The results showed that the novel contrast agent could become a useful tool in early detection of cancer. © 2014 World Molecular Imaging Society

Stochastic particle packing with specified granulometry and porosity

This work presents a technique for particle size generation and placement in arbitrary closed domains. Its main application is the simulation of granular media described by disks. Particle size generation is based on the statistical analysis of granulometric curves which are used as empirical cumulative distribution functions to sample from mixtures of uniform distributions. The desired porosity is attained by selecting a certain number of particles, and their placement is performed by a stochastic point process. We present an application analyzing different types of sand and clay, where we model the grain size with the gamma, lognormal, Weibull and hyperbolic distributions. The parameters from the resulting best fit are used to generate samples from the theoretical distribution, which are used for filling a finite-size area with non-overlapping disks deployed by a Simple Sequential Inhibition stochastic point process. Such filled areas are relevant as plausible inputs for assessing Discrete Element Method and similar techniques