A Review of the `BMS' Package for R

This paper describes the relative merits and attractiveness of the newest Bayesian model averaging package, BMS, available in the statistical software R to implement a Bayesian model averaging exercise. This package provides the user with a wide range of customizable priors for conducting a BMA analysis, provides ample graphs to visualize the results and offers several alternative model search mechanisms.Model Averaging, Zellner's g Prior, BMS

Bayesian Model Averaging in R

Bayesian model averaging has increasingly witnessed applications across an array of empirical contexts. However, the dearth of available statistical software which allows one to engage in a model averaging exercise is limited. It is common for consumers of these methods to develop their own code, which has obvious appeal. However, canned statistical software can ameliorate one's own analysis if they are not intimately familiar with the nuances of computer coding. Moreover, many researchers would prefer user ready software to mitigate the inevitable time costs that arise when hard coding an econometric estimator. To that end, this paper describes the relative merits and attractiveness of several competing packages in the statistical environment R to implement a Bayesian model averaging exercise.Model Averaging, Zellner's g Prior, BMS

Decomposing The Conditional Variance of Cross-Country Output

A well established fact in the growth empirics literature is the increasing variation in output per capita across countries. This phenomena however does not adequately describe changes in the distribution of output since it does not account for changes in the covariates which undoubtedly in influence per capita output levels. We propose a robust, nonparametric decomposition of the conditional variation of per capita output and find that OECD countries have experienced diminishing conditional variation while other regions have experienced increasing conditional variation. Our decomposition suggests that most of these changes in the conditional variance of output is due to unobserved factors not accounted for by the traditional growth determinants. In addition to this we show as these factors played very different roles over time and across regions.Generalized Kernel, Nonparametric, Conditional Variation

Development and application of the method of distributed volumetric sources to the problem of unsteady-state

This work introduces the method of Distributed Volumetric Sources (DVS) to solve the transient and pseudosteady-state flow of fluids in a rectilinear reservoir with closed boundaries. The development and validation of the DVS solution for simple well/fracture configurations and its extension to predict the pressure and productivity behavior of complex well/fracture systems are the primary objectives of this research. In its simplest form, the DVS method is based on the calculation of the response for a closed rectilinear system to an instantaneous change in a rectilinear, uniform volumetric source inside the reservoir. Integration of this response over the time provides us with the solution to a continuous change (constantrate pressure response). Using the traditional material balance equations and the DVS pressure response of the system, we can calculate the productivity index of the system in both transient and pseudosteadystate flow periods, which enables us to predict the production behavior over the life of the well/reservoir. Solutions for more complex situations, such as sources with infinite or finite-conductivity (i.e., a fracture), are provided using discretization of the source. This work considers the case of a complex system with a horizontal well intersecting multiple transverse fractures as an example to show the ability (and flexibility) of the new method. The DVS solution method provides accurate solutions for complex well/fracture configurations — which will help engineers to design and implement optimum well completions. The DVS solutions has been validated by comparing to existing analytical solutions (where applicable), as well as to numerical (simulation) solutions. In all cases the DVS solution was successfully validated — at least in a practical sense — specifically in terms of the accuracy and precision of the DVS solution. As the DVS method is approximate (at early times), there are small discrepancies which are of little or no practical consequence. In terms of computation times, because of its analytic nature, the DVS method is not always optimal in terms of speed for certain problems, but the DVS approach is similar in computation speed with commercial reservoir simulation programs

On the effect of texture on kinking non-linear elasticity of MAX phases and MAX-reinforced Mg matrix composites

The MAX phases and hexagonal metals, among many other plastically anisotropic solids with c/a ratios > 1.5, have been recently classified as kinking nonlinear elastic (KNE) solids – the signature of which is the formation of fully reversible, hysteretic stress-strain loops during cyclic loadings.Herein, a unique and novel class of Mg matrix composites reinforced with Ti2AlC was fabricated, for the first time, by spontaneous melt infiltration. The ~ 35 nm Mg grains that constituted the matrix of these composites were exceptionally stable: repeatedly heating the composite to 700 °C – 50 °C above the melting point of Mg – remarkably did not lead to any coarsening. At 380±20 MPa, 700±10 MPa and 1.5±0.5 GPa, the ultimate tensile and compressive strengths and Vickers hardness of these composites, respectively, are significantly greater than other pure Mg-composites reported in the literature, a fact attributed to nanocrystalline nature of the Mg-matrix. The advantages of melt infiltration as a processing technique are affordability and ease of scalability. To make these composites, all one needs to do is melt bulk Mg above a porous preform of Ti2AlC; nature does the rest.Because kinking is a form of plastic instability, orienting the Ti2AlC grains, prior to infiltration, with their basal planes parallel to the loading direction led to exceptionally high values of dissipated energy per unit volume per cycle, Wd. At 450 MPa, Wd of these composites with this texture was found to be ≈ 0.6 MJ/m3, believed to be the highest ever reported for a crystalline solid. Counterintuitively, the Wd’s of bulk Ti2AlC samples, in which the basal planes are normal to the applied load were higher than those in which the basal planes were loaded parallel to the loading axis. In the case of the composites, the relatively softer Mg phase in between the Ti2AlC grains allows the latter to kink, while in the Ti2AlC bulk samples the majority of the plate-like grains of Ti2AlC seem to be constrained by the minority grains. In-situ neutron diffraction experiments suggest that the minority grains are kinking significantly more than the majority grains. The KNE microscale model – previously developed to explain kinking nonlinear elasticity – is in excellent agreement with the experimental results obtained in this work. The model is capable of calculating the critical resolved shear stresses, CRSS, of basal plane dislocations making up the incipient kink bands – the reversible micro-constituent responsible for the nonlinearity and Wd. The model can also estimate the Taylor factor that, as far as we are aware, is the first time that factor has been measured experimentally. The Taylor factor – that ranged from 1.8 to 3.0 – was found to be a function of texture and grain size.In summary, this work shows that the MAX-metal composites and their monolithic MAX phase counterparts fabricated herein are all KNE solids and their KNE behavior is a strong function of texture, and characterized by the formation of fully reversible hysteretic stress-strain loops under uniaxial cyclic compression.Ph.D., Materials Science and Engineering -- Drexel University, 200

Yield and Yield Components of Faba Bean

ABSTRACT This study set out to investigate the effect of bio-fertilizers containing nitrogen-fixing bacteria and phosphorus on grain yield and yield components of Faba bean. To this end a factorial experiment on the basis of randomized complete block design with four replications was conducted in Behbahan region at South eastern part of Khuzestan Province of Iran. The experimental treatments included Nitroxin containing nitrogenfixing bacteria in three levels of 0, 250, and 500 cc per 1000 m 2 and phosphorus biofertilizer (fertile 2 phosphates) containing phosphorus-fixing bacteria in three levels of 0, 100, and 150 g.ha -1 . The results showed that the effect of treatments with phosphorus bio-fertilizer and Nitroxin on grain yield, biological yield, and harvest index, number of pods per plant, number of grain per pod, 1000-grain weight, and leaf area index was significant at 1% level. The highest grain yield, biological yield, harvest index, number of pods per plant, number of grains per pod, 1000-grain weight, and leaf area index belonged to the treatment with consumption of 500 cc Nitroxin per 1000 m 2 and 150 g.ha -1 phosphorus bio-fertilizer and the lowest rates belonged to the control treatment

Isothermal Oxidation of Ti\u3csub\u3e2\u3c/sub\u3eSC in Air

The oxidation behavior of fully dense Ti2SC was studied thermogravimetrically in air in the 500–800°C temperature range. The oxidation product was a single-layer of rutile in all cases. At 800°C, the oxide layer was not protective and the oxidation kinetics were rapid. At 600 and 700°C, and up to ~50 h, the kinetics were parabolic before they became linear. It was only at 500°C that the weight gain reached a plateau after a 50 h initial parabolic regime. Mass spectrometry of the gases evolved during oxidation confirmed that both CO2 and SO2 are oxidation products. The overall oxidation reaction is thus Ti2SC + 4O2 → 2TiO2 + SO2 + CO2. On the basis of this and previous work, we conclude that oxidation occurs by the outward diffusion of titanium, sulfur, and carbon, the latter two either as atoms or in the form of CO2 and SO2 and, most probably, the inward diffusion of oxygen. Mesopores and microcracks were found in all rutile layers formed except those formed at 500°C. The presence of these defects is believed to have led to significantly higher oxidation rates as compared to other rutile-forming ternary carbides, such as Ti3SiC2

Salivary levels of IgE and ECP in patients with recurrent aphthous stomatitis

Recurrent aphthous stomatitis is a common oral mucosa disease, with no specific etiology. Atopy has been implicated in the development of this disease. In this study, the salivary levels of immunoglobulin E (IgE) and eosinophil cationic protein (ECP) were measured as allergy-related biomarkers in patients with aphthous stomatitis. In this case-control study, non-stimulated saliva was collected from 85 participants and IgE and ECP were measured. Data were analyzed in SPSS 20 through the Mann-Whitney test, and p<0.05 was considered significant. The salivary levels of IgE and ECP were 1.11±0.65 Iu/ml and 26.93±6.95 ng/ml in the case group and 0.73±0/39 Iu/ml and 21.97±6.72 ng/ml in the control group. There was a significant difference between the two groups in terms of salivary levels of IgE and ECP (p=0.001). The results showed that patients with oral aphthous had higher levels of salivary IgE and ECP than controls. Therefore, measurement of these biomarkers may be useful in the initial evaluation of patients with aphthous stomatitis

Increased Plasma Levels of Soluble CD27 among HIV/HCV Co-infected and HIV/HCV/GBV-C Triply Infected Subjects

CD27 is a biomarker associated with both T-cells and B-cells activation .Plasma soluble CD27 (sCD27) was identified as  a marker of disease outcome in Human Immunodeficiency Virus (HIV) infection .Testing of plasma sCD27 represents a good tool to monitor the change of immune activation during HIV infection.We sought to analyses role of Hepatitis C Virus (HCV) and also GB Virus type C (GBV-C) co-infections on HIV-related immune activation, through measuring sCD27 plasma levels.Blood samples from a total of 86 patients with HIV infection were taken. Plasmas were analyzed for HCV using serologic test and GBV-C by reverse transcriptase polymerase chain reaction (RT-PCR). CD4+ and CD8+T-cell counts were evaluated by CD3/CD4+ and CD3/CD8+ double staining of whole blood followed by flow cytometric analysis .Then  Cross-sectional comparison of sCD27 plasma levels was carried out among patients : HIV (n=20), HIV/ GBV-C (n=14), HIV/ (HCV) (n=26) and HIV/HCV/GBV-C (n=26).Plasma level of sCD27 was higher in HIV/HCV/GBV-C patients as compared to HIV mono-infected patients (p= 0.006) and based on results there was significant differences in the plasma levels of sCD27 between HIV-infected individuals with and without HCV coinfection (P=0.017) and also correlation between sCD27 and percent of CD4+T-cells was in highest level among HIV/HCV co-infected patients group [r= -0.59 (p=0.001)]. High levels of sCD27 among HIV/HCV patients argues in favor of sCD27 plasma level determination for monitoring of clinical features among HIV/HCV coinfected patients

Low-Dose Fentanyl, Propofol, Midazolam, Ketamine and Lidocaine Combination vs. Regular Dose Propofol and Fentanyl Combination for Deep Sedation Induction; a Randomized Clinical Trial

Introduction: Need for procedural sedation and analgesia (PSA) is felt in emergency department (ED) more and more each day. This study aimed to compare the effectiveness of low-dose fentanyl, propofol, midazolam, ketamine and lidocaine combination with regular dose of propofol and fentanyl combination for induction of deep sedation.Methods: In this single-blind clinical trial, candidate patients for sedation and analgesia aged more than 15 and less than 60 years old, with pain score ≥6 were allocated to one of the groups using block randomization and were compared regarding onset of action, recovery time, and probable side effects.Results: 125 patients with the mean age of 37.8 ± 14.3 years were randomly allocated to each group. 100% of the patients in group 1 (5 drugs) and 56.5% of the patients in group 2 (2 drugs) were deeply sedated in the 3rd minute after injection. The 2 groups were significantly different regarding onset of action (p = 0.440), recovery time (p = 0.018), and treatment failure (p &lt; 0.001).Conclusion: Low-dose fentanyl, propofol, midazolam, ketamine and lidocaine combination was more successful in induction of deep sedation compared to regular dose of propofol and fentanyl combination. Recovery time was a little longer in this group and both groups were similar regarding drug side effects and effect on vital signs