Some Correlators of SU(3)3SU(3)_3 WZW Models on Higher-Genus Riemann Surfaces

Using the conformal embedding on the torus, we can express some characters of $SU(3)_3$ in terms of $SO(8)_1$ characters. Then with the help of crossing symmetry, modular transformation and factorization properties of Green functions, we will calculate a class of correlators of $SU(3)_3$ on arbitrary Riemann surfaces. This method can apply to all $k>1$ WZW models which can be conformally embedded in some $k=1$ WZW models.Comment: 19 page

Quantum Chains with GLq(2)GL_q(2) Symmetry

Usually quantum chains with quantum group symmetry are associated with representations of quantized universal algebras $U_q(g)$ . Here we propose a method for constructing quantum chains with $C_q(G)$ global symmetry , where $C_q(G)$ is the algebra of functions on the quantum group. In particular we will construct a quantum chain with $GL_q(2)$ symmetry which interpolates between two classical Ising chains.It is shown that the Hamiltonian of this chain satisfies in the generalised braid group algebra.Comment: 7 pages,latex,this is the completely revised version of my paper which is submitted for publicatio

Exactly solvable models through the generalized empty interval method, for multi-species interactions

Multi-species reaction-diffusion systems, with nearest-neighbor interaction on a one-dimensional lattice are considered. Necessary and sufficient constraints on the interaction rates are obtained, that guarantee the closedness of the time evolution equation for $E^{\mathbf a}_n(t)$'s, the expectation value of the product of certain linear combination of the number operators on $n$ consecutive sites at time $t$. The constraints are solved for the single-species left-right-symmetric systems. Also, examples of multi-species system for which the evolution equations of $E^{\mathbf a}_n(t)$'s are closed, are given.Comment: 18 pages, LaTeX2e, no figure

Generalized simplicial chiral models

Using the auxiliary field representation of the simplicial chiral models on a (d-1)-dimensional simplex, the simplicial chiral models are generalized through replacing the term Tr(AA^{\d}) in the Lagrangian of these models by an arbitrary class function of AA^{\d}; V(AA^{\d}). This is the same method used in defining the generalized two-dimensional Yang-Mills theories (gYM_2) from ordinary YM_2. We call these models, the ``generalized simplicial chiral models''. Using the results of the one-link integral over a U(N) matrix, the large-N saddle-point equations for eigenvalue density function \ro (z) in the weak (\b >\b_c) and strong (\b <\b_c) regions are computed. In d=2, where the model is in some sense related to the gYM_2 theory, the saddle-point equations are solved for \ro (z) in the two regions, and the explicit value of critical point \b_c is calculated for $V(B)$=Tr$B^n$ (B=AA^{\d}). For $V(B$)=Tr$B^2$,Tr$B^3$, and Tr$B^4$, the critical behaviour of the model at d=2 is studied, and by calculating the internal energy, it is shown that these models have a third order phase transition.Comment: 14 pages, LaTex, some minor English corrections, will be published in Nuc. Phys.

Asymptotic behavior of w in general quintom model

For the quintom models with arbitrary potential $V=V(\phi,\sigma)$, the asymptotic value of equation of state parameter w is obtained by a new method. In this method, w of stable attractors are calculated by using the ratio (d ln V)/(d ln a) in asymptotic region. All the known results, have been obtained by other methods, are reproduced by this method as specific examples.Comment: 8 pages, one example is added, accepted for publication in Gen. Rel. Gra

On the phase structure of two--dimensional generalized Yang--Mills theories

The phase structure of the generalized Yang--Mills theories is studied, and it is shown that {\it almost} always, it is of the third order. As a specific example, it is shown that all of the models with the interaction $\sum_j (n_j-j+N)^{2k}$ exhibit third order phase transition. ($n_j$ is the length of the $j$-th row of the Yang tableau corresponding to U($N$).) The special cases where the transition is not of the third order are also considered and, as a specific example, it is shown that the model $\sum_j (n_j-j+N)^2+g\sum_j (n_j-j+N)^{4}$ exhibits a third order phase transition, except for $g=27\pi^2/256$, where the order of the transition is 5/2.Comment: 14 pages, LaTex, one paragraph is added to introduction section, to describe the 5/2 phase transition, accepted for publication in Nucl. Phys. B (2001

A novel method to design water spray cooling system to protect floating roof atmospheric storage tanks against fires

Hydrocarbon bulk storage tank fires are not very common, but their protection is essential due to severe consequences of such fires. Water spray cooling system is one of the most effective ways to reduce damages to a tank from a fire. Many codes and standards set requirements and recommendations to maximize the efficiency of water spray cooling systems, but these are widely different and still various interpretations and methods are employed to design such systems. This article provides a brief introduction to some possible design methods of cooling systems for protection of storage tanks against external non-contacting fires and introduces a new method namely “Linear Density Method” and compares the results from this method to the “Average Method” which is currently in common practice. The average Method determines the flow rate for each spray nozzle by dividing the total water demand by the number of spray nozzles while the Linear Density Method determines the nozzle flow rate based on the actual flow over the surface to be protected. The configuration of the system includes a one million barrel crude oil floating roof tank to be protected and which is placed one half tank diameter from a similar adjacent tank with a full surface fire. Thermal radiation and hydraulics are modeled using DNV PHAST Version 6.53 and Sunrise PIPENET Version 1.5.0.2722 software respectively. Spray nozzles used in design are manufactured by Angus Fire and PNR Nozzles companies. Schedule 40 carbon steel pipe is used for piping. The results show that the cooling system using the Linear Density Method consumes 3.55% more water than the design using the average method assuming a uniform application rate of 4.1 liters per minute. Despite higher water consumption the design based on Linear Density Method alleviates the problems associated with the Average Method and provides better protection

Evaluation of Protective and Immunomodulatory Effects of Hydroalcoholic Extract of Scrophularia striata on Silver Nanoparticle-Induced Toxicity in Male Rats

Introduction: Recently, silver nanoparticles (Ag-NPs) have found extensive and raising biomedical applications. Ag-NPs may lead to increased rate of toxicity on human health and environment. Because of the high antioxidant potential of the Scrophularia striata, the aim of the present study was to investigate the protective influence of Scrophularia striata against Ag-NPs-induced toxicity. Materials and Methods: Thirty male Wistar rats were randomly divided into 5 groups (n=6 for each group). Group 1 was normal control rats. Group 2 received only Ag-NPs (200 ppm). In groups 3 to 5, the rats were pretreated with different concentrations (20, 60 and 180 mg/kg) of the Scrophularia striata extract, respectively and then were treated with Ag-NPs to induce toxicity. Animals were treated once daily by gavage over a period of 30 days. At the end of the treatment period, blood samples were collected and serum IgG, IgM, C3, C4, and CRP levels were determined. Data were statistically analyzed through one-way ANOVA, followed by Tukey’s post hoc test. Results: Oral administration of Ag-NPs evoked a significant increase in the serum IgG, IgM, C3, C4, and CRP levels, compared with those in the control group (P&lt;0.05). These changes were ameliorated through treatment with Scrophularia striata extract at different doses as compared with the Ag-NPs-treated group (P&lt;0.05). Conclusion: The extract was found to be as an effective immunomodulatory agent against Ag-NPs-induced toxicity presumably due to its active compounds with medicinal value

A Review of Common Problems in Design and Installation of Water Spray Cooling and Low Expansion Foam System to Protect Storage Tanks Containing Hydrocarbons Against Fires

Tank fires are rare but carry significant potential risk to life and property. For this reason fire protection of tanks is critical. Fixed Low expansion foam and water spray cooling systems are one of the most effective and economical ways to reduce damages to a tank from fire. Such systems are currently installed in many companies but are not effective enough and require involvement of firefighters which in turn threaten their lives. This paper studies in a systematic way the problems of foam and cooling systems currently installed in a few domestic companies which operate storage tanks with focus on floating and fixed roof atmospheric tanks containing hydrocarbons and offers possible solutions for more efficient installation, design and operation of such systems

Relapses or de-novo IgA nephropathy following COVID-19 vaccination : a narrative review

Immunoglobulin A (IgA) nephropathy is the most common type of glomerulonephritis worldwide characterized by excessive serum levels of glycosylated which triggers the generation of glycan-specific IgG and IgA autoantibodies. This pathological condition results in the formation of circulatory IgA immune complexes, which are essential for the development of glomerular inflammation, especially IgA nephropathy. The serum galactosylated IgA1, IgG, and IgA autoantibodies are suggested as the biomarkers of IgA nephropathy since IgA antibodies are early markers for disease activity too. Serum IgA antibodies emerged as the early COVID-19-specific antibody response about two days after initial symptoms of COVID-19 in comparison with IgG and IgM antibody concentrations, which appeared after five days. IgA nephropathy is frequently presented as microscopic or macroscopic hematuria and proteinuria with a male predominance. COVID-19 infection can include several organs aside from the lungs, such as kidneys through different mechanisms. It is demonstrated in most cases that short-lasting symptoms such as gross hematuria resolve either spontaneously or following a short course of steroids. This review summarized the reported cases of relapses or denovo reported cases of relapses or de-novo IgA nephropathy and IgA vasculitis following COVID-19 vaccination