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We calculate the strong coupling constants among the doubly heavy spin- 3 2 baryons Ξ QQ ∗ and Ω QQ ∗ , with Q and Q ′ being c or b quark, with light vector meson by means of the light-cone QCD sum rules. The matrix elements defining these vertices are described by four coupling constants g 1 , g 2 , g 3 , and g 4 . The unwanted pollution coming from the doubly heavy spin- 1 2 baryons are removed by a special ordering of Dirac matrices and selection of appropriate Lorentz structures. The strong coupling constants are basic parameters that carry information on the nature of the strong interaction among hadronic multiplets. Investigation of these parameters may help physicists in the construction of the strong potentials among the doubly heavy baryons and light vector mesons. The values obtained for the strong coupling constants may also help experimental groups in analyses of the data produced at various hadron colliders. [ABSTRACT FROM AUTHOR]

Due to their light weights and high load carrying capacities, composite structures are widely used in various industrial applications especially in aerospace industry. Strength to weight ratio is known to be as one of the most critical design parameters in these structures. In this paper, geometrical parameters of composite lattice structures are optimized to obtain the desired strength to weight ratio using finite element method, neural networks and ABC algorithm. At first, the finite element model is validated by experimental results and neural network is employed as the fitness function. The ABC algorithm is also applied to achieve the optimized strength to weight ratio. The results obtained from PSO algorithm on the basis of neural network have shown reasonable agreement with those of the finite element simulation. Increasing the thickness of the outer shell causes the structural strength-to-weight ratio to rise by 50 percent. The next effective parameter is reduction of rib angle which provides an increase of 30 percent in strength-to-weight ratio. Although Stiffeners (ribs) have a major role in load carrying, increasing the rib thickness causes the structural weight to rise. Thus compared with the two previous parameters, they do not have a significant effect on the strength of structures. [ABSTRACT FROM AUTHOR]

This paper presents a new method for non-linear analysis of structures using an iterative method originated from quadrature rule based on spline function. At first, the above-mentioned method is developed for solving systems of non-linear algebraic equations and then it is implemented on structural problems. In this procedure like many other state of the art methods, the non-linear equations are linearized by evaluating the non-linear terms with the known solution from the preceding iteration. The proposed method is constructed as a predictor-corrector one, must frequently taking Newton's method in the first iteration. For this method, a simple step-by-step algorithm was implemented and presented to calculate non-linear analysis of structures. It should be noted that currently, the proposed method is incapable of tracing the equilibrium curve after passing the limit points. The presented method incorporates the known information at each stage of the loading process to determine the subsequent unknown variables. Compared with the classic Newton-Raphson algorithm and a recently proposed two-point method, it offers a strategy that can be deployed to reduce the number of the iterations to trace the equilibrium path in non-linear analysis of structures. [ABSTRACT FROM AUTHOR]

Airborne particulate matter has been collected by a high volume and a Gent-type stacked filter unit (SFU) low volume sampler during the 2000-2001 period. The high volume sampler used S&S cellulosic and the SFU two Nuclepore polycarbonate filters to collect fine and coarse size fractions. The elemental analysis of the collected TSP, fine and coarse particles has been performed using instrumental neutron activation analysis and atomic absorption spectrometry. Twenty-two trace elements on Nuclepore and twenty-four elements on S&S filters have been measured. The collected data have been compared with the previous data of Tehran air and with other cities in the world. [ABSTRACT FROM AUTHOR]

Persons with rheumatoid arthritis (RA) have increased risk of myocardial infarction (MI). Overlapping associations with MI of weighted genetic risk scores (wGRS) for coronary artery disease (CAD) and RA is unknown in a population-based setting. Data from the prospective Nord-Trøndelag Health Study (HUNT2: 1995–1997 and HUNT3: 2006–2008) were used. wGRS added each participant's carriage of all risk variants weighted by the coefficient from published association studies. Published wGRS for CAD and RA were analysed in Cox regression with MI as outcome, age as analysis time, and censoring at the first MI, death, or 31.12.2017. 2609 of 61,465 participants developed MI during follow-up (mean 17.7 years). The best-fitting wGRS for CAD and RA included 157 and 27 single-nucleotide polymorphisms, respectively. In multivariable analysis including traditional CAD risk factors, the CAD wGRS was associated with MI [hazard ratio = 1.23 (95% CI 1.18–1.27) for each SD increase, p < 0.0001] in RA patients (n = 433) and controls. The RA wGRS was not significant (p = 0.06). Independently from traditional risk factors, a CAD wGRS was significantly associated with the risk for MI in RA patients and controls, whereas an RA wGRS was not. The captured genetic risk for RA contributed little to the risk of MI. [ABSTRACT FROM AUTHOR]

The doubly charmed Ξ cc + + (c c u) state is the only listed baryon in PDG, which was discovered in the experiment. The LHCb collaboration gets closer to discovering the second doubly charmed baryon Ξ cc + (c c d) , hence the investigation of the doubly charmed/bottom baryons from many aspects is of great importance that may help us not only get valuable knowledge on the nature of the newly discovered states, but also in the search for other members of the doubly heavy baryons predicted by the quark model. In this context, we investigate the strong coupling constants among the Ξ cc + (+) baryons and π 0 (±) mesons by means of light cone QCD sum rule. Using the general forms of the interpolating currents of the Ξ cc + (+) baryons and the distribution amplitudes (DAs) of the π meson, we extract the values of the coupling constants g Ξ cc Ξ cc π . We extend our analyses to calculate the strong coupling constants among the partner baryons with π mesons, as well, and extract the values of the strong couplings g Ξ bb Ξ bb π and g Ξ bc Ξ bc π . The results of this study may help experimental groups in the analyses of the data related to the strong coupling constants among the hadronic multiplets. [ABSTRACT FROM AUTHOR]

In most non-perturbative methods in hadron physics the calculations are started with a correlation function in terms of some interpolating and transition currents in x -space. For simplicity, the calculations are then transformed to the momentum space by a Fourier transformation. To suppress the contributions of the higher states and continuum, and enhance the ground state contribution, the Borel transformation as well as continuum subtraction are applied with the help of quark-hadron duality assumption. In the present study we work out the mathematics required for these processes in the case of light and multi-heavy hadrons. We address a well-known problem in the subtraction of the effects of the higher states and continuum and discuss how we find finite results without any divergence by using an appropriate representation of the modified Bessel functions, appearing in the heavy quark propagator, and successive applications of the Borel transformations, which lead to more suppression of the higher states and continuum contributions. The results obtained can be used in the determination of the spectroscopic and decay properties of the multi-heavy standard and non-conventional (exotic) systems in many non-perturbative methods, especially the QCD sum rules. [ABSTRACT FROM AUTHOR]

A novel modified glassy carbon electrode with ytterbium fluoride nanoparticles (YFNPs)-multiwalled carbon nanotubes (MWCNTs) was fabricated and then successfully used for the simultaneous determination of ascorbic acid (AA), dopamine (DA) and uric acid (UA). YFNPs were successfully coated on the MWCNTs via the intermediate of noncovalent hydrophobic interactions of the MWCNTs surface with sodium dodecyl sulfate. The YFNPs and immobilization of YFNPs on MWCNTs were confirmed by transmission electron microscopy. The particle size of YFNPs was measured to be around 45 nm. The catalytic peak currents for AA, DA and UA were linearly dependent on their concentrations in the range of 2.0-600.0, 2.0-560.0 and 1.8-640.0 μM, respectively, with the corresponding detection limits of 0.77, 0.22 and 0.17 μM. The modified electrode provided good sensitivity and stability, and was successfully applied for the simultaneous determination of AA, DA and UA in human blood serum and urine samples. [ABSTRACT FROM AUTHOR]