Inhibitory effect of lactone fractions and individual components from three species of the Achillea millefolium complex of Bulgarian origin on the human neutrophils respiratory burst activity

Achillea species are widely used in folk medicine for treatment of inflammatory diseases. The inhibitory effect on the human neutrophils respiratory burst activity of total extracts, their fractions and some main constituents of the flower heads from Achillea asplenifolia, A. collina and A. distans belonging to A. millefolium complex of Bulgarian origin, were tested by the modified method of Tan and Berridge. Seven from the investigated fractions showed activity similar or higher than that of indomethacine and might be evaluated as nonsteroidal anti-inflammatory agents.     

Quantum Walk on the Generalized Birkhoff Polytope Graph

We study discrete-time quantum walks on generalized Birkhoff polytope graphs (GBPGs), which arise in the solution-set to certain transportation linear programming problems (TLPs). It is known that quantum walks mix at most quadratically faster than random walks on cycles, two-dimensional lattices, hypercubes, and bounded-degree graphs. In contrast, our numerical results show that it is possible to achieve a greater than quadratic quantum speedup for the mixing time on a subclass of GBPG (TLP with two consumers and m suppliers). We analyze two types of initial states. If the walker starts on a single node, the quantum mixing time does not depend on m, even though the graph diameter increases with it. To the best of our knowledge, this is the first example of its kind. If the walker is initially spread over a maximal clique, the quantum mixing time is O(m/ϵ), where ϵ is the threshold used in the mixing times. This result is better than the classical mixing time, which is O(m1.5/ϵ).     

Nanoparticles of Costus speciosus Ameliorate Diabetes-Induced Structural Changes in Rat Prostate through Mediating the Pro-Inflammatory Cytokines IL 6, IL1β and TNF-α

Diabetes mellitus is a common global health problem. Among the complications that are frequently associated with DM are the alternation of sexual function and fertility, especially in young men. This study aimed to assess the efficacy of nanoparticles of Costus speciosus (C. speciosus) in preserving the prostatic structure of diabetic rats and to explore the mechanism behind this effect. A model of DM was induced in male albino rats by a single intraperitoneally injection of streptozotocin (STZ, 60 mg/kg body weight). Five groups (n = 10 each) of rats were included in this study: the control, C. speciosus gold nanoparticles-treated (150 mg/kg body weight through gastric intubation for 30 days), untreated diabetic, metformin-treated diabetic (500 mg/kg/day gastric intubation for 30 days) and the C. speciosus-treated diabetic group. The blood glucose, insulin and testosterone levels as well as oxidants/antioxidants status were assessed in the serum. Gene expression of proinflammatory cytokines TNF-α, IL1β and IL-6 were assessed in the prostate homogenate. At the end of the experiment, the rats were sacrificed and the prostate was dissected out and prepared for histopathological and immunohistochemistry study using Ki67 and Bcl-2. C. Speciosus nanoparticles significantly decreased (p = 0.03) the blood glucose level while significantly increasing insulin (p = 0.01) and testosterone (p = 0.04) levels compared to the untreated diabetic rats. Oxidants/antioxidants status was markedly improved after administration of C. speciosus. Prostatic expression of the mRNA of pro-inflammatory cytokines IL-6, IL1β and TNF-α was down-regulated in metformin- and C. speciosus-treated rats. The histological structure of the ventral prostate was preserved in metformin- and C. speciosus-treated diabetic rats with a significantly thicker epithelial cell layer and significant increase immunoexpression in Bcl-2 and Ki67. In conclusion, the protective effect induced by C. speciosus nanoparticles on the prostate of diabetic rats might be directly mediated through the down-regulation of inflammatory cytokines and the up-regulation of antioxidant activity and indirectly mediated through the anti-hyperglycemic effect through enhancing insulin secretion.     

A chaotic map with infinite number of equilibria in a bounded domain

The European Physical Journal Special Topics - Although chaotic flows with special properties in their equilibria have been investigated widely, such an effort about chaotic maps has been...     

A novel operational vector for solving the general form of distributed order fractional differential equations in the time domain based on the second kind Chebyshev wavelets

Numerical Algorithms - The main aim of this research study is to present a new and efficient numerical method based on the second kind Chebyshev wavelets for solving the general form of distributed...     

Species-Related Difference to Noise Reduction Between Trees in Urban Forest: The Abidar Forest Park (Case Study)

Sound pollution is one of the most important urban problems which endangers mental and physical health of the residents. This study was aimed to assess the influence of different tree species, including Fraxinus rotundifolia, Robinia pseudoacacia, Platanus orientalis, Platycladus orientalis, and Pinus eldarica, in reducing noise pollution in the Abidar Forest Park. A further objective was to identify the contaminated areas of Sanandaj city and to propose suitable noise absorbent tree species in consistent conditions. For each tree stands the noise measurements were performed during intervals at frequencies of 250, 500 and 1000 Hz, besides an open area with the same topography. With regards to the second purpose, a total of 50 stations with residential, commercial, residentialcommercial, and green space applications were selected across the city. Equivalent Continuous Sound Pressure Level (Leq) was determined in five replicates for 30 min. The measurements were performed under stable weather conditions and low wind velocity at 17:00 (traffic peak) in summer and fall. All of the Leq values were above the threshold noise level. The highest noise reduction was recorded in summer (i.e., green season); Platanus and Platycladus species demonstrated the highest and lowest noise absorption (31.43 dB and 22.28 dB, respectively). Furthermore, a meaningful difference was observed between Leq values of commercial, residential, commercial-residential, and green space urban applications, and the central parts of the city showed noticeable noise pollution. Taken together, due to being exposed to higher than the acceptable threshold noise level, the residents of Sanandaj will be endangered to health problems in the near future; thus consideration should be given to the noise pollution sources.     

Stereoretentive elimination and trans-olefination of the dicationic dipalladium moiety [Pd2Ln]2+ bound on 1,3,5-trienes

The reaction of [Pd(2)(CH(3)CN)(6)][BF(4)](2) (1) with 1,3,5-hexatriene, 1,6-diphenyl-1,3,5-hexatriene (DPHT), or 2,2,9,9-tetramethyl-3,5,7-decatriene (DBHT) afforded bi-eta(3)-allyldipalladium complexes 3, 4, or 5. The reaction of 1 and DBHT proceeded in a stereospecific (syn) manner when the reaction was carried out in CD(2)Cl(2) under aerobic conditions, while a mixture of two diastereomers was formed under N(2) atmosphere. The two diastereomers (5-E,Z,E-antifacial and 5-E,E,E-antifacial) formed from DBHT were isolated, and the structure of 5-E,Z,E-antifacial, which was kinetically formed from the reaction of 1 and (E,E,E)-DBHT, was determined by X-ray diffraction analysis. Addition of phosphine ligands (PPh(3) or dppm) to the dinuclear adduct 5-E,Z,E-antifacial or 5-E,E,E-antifacial in acetonitrile resulted in the stereospecific (syn) elimination of [Pd(2)(PPh(3))(2)(CH(3)CN)(4)][BF(4)](2) (2) or [Pd(2)(dppm)(2)(CH(3)CN)(2)][BF(4)](2) (6). During the PPh(3)-induced dinuclear elimination, the phosphine adducts 7 that retain bi-eta(3)-allyldipalladium structure were observed initially. The phosphine adduct generated from 5-E,E,E-antifacial was isolated and structurally characterized by X-ray diffraction analysis. The reaction of 1 and DPHT in CH(2)Cl(2) afforded unique dipalladium sandwich compounds [Pd(2)(mu-eta(3):eta(3)-DPHT)(2)][BF(4)](2) (8). Interconversion between the sandwich complexes and half-sandwich complexes occurred in a stereoretentive manner. The structure of the sandwich complex 8-E,Z,E formed from 4-E,E,E-antifacial and (E,Z,E)-DPHT was determined by X-ray diffraction analysis. Transfer of the dipalladium moiety [Pd(2)(CH(3)CN)(4)](2+) from DPHT ligand of 4-E,E,E-antifacial onto DBHT ligand proceeded in a stereoretentive manner. The observed stereoretentive dinuclear process is featured by the pairwise behavior of two palladium atoms sitting on the triene pi-plane. In the dinuclear elimination, the two Pd atoms that are initially in the divalent state and bound on the opposite faces (antifacial) come to the synfacial positions to form a Pd-Pd bond prior to dissociation. These results represent the unique property of conjugated olefin as the multidentate ligands for metal-metal moieties.     

An <Emphasis Type="BoldItalic">O</Emphasis>(<Emphasis Type="BoldItalic">h</Emphasis><Superscript><Emphasis Type="Bold">6</Emphasis></Superscript>) numerical solution of general nonlinear fifth-order two point boundary value problems

A sixth-order numerical scheme is developed for general nonlinear fifth-order two point boundary-value problems. The standard sextic spline for the solution of fifth order two point boundary-value problems gives only O(h ²) accuracy and leads to non-optimal approximations. In order to derive higher orders of accuracy, high order perturbations of the problem are generated and applied to construct the numerical algorithm. O(h ⁶) global error estimates obtained for these problems. The convergence properties of the method is studied. This scheme has been applied to the system of nonlinear fifth order two-point boundary value problem too. Numerical results are given to illustrate the efficiency of the proposed method computationally. Results from the numerical experiments, verify the theoretical behavior of the orders of convergence.     

Burst-duration mechanism of in-phase bursting in inhibitory networks

We study the emergence of in-phase and anti-phase synchronized rhythms in bursting networks of Hodgkin-Huxley-type neurons connected by inhibitory synapses. We show that when the state of the individual neuron composing the network is close to the transition from bursting into tonic spiking, the appearance of the network’s synchronous rhythms becomes sensitive to small changes in parameters and synaptic coupling strengths. This bursting-spiking transition is associated with codimension-one bifurcations of a saddle-node limit cycle with homoclinic orbits, first described and studied by Leonid Pavlovich Shilnikov. By this paper, we pay tribute to his pioneering results and emphasize their importance for understanding the cooperative behavior of bursting neurons. We describe the burst-duration mechanism of inphase synchronized bursting in a network with strong repulsive connections, induced by weak inhibition. Through the stability analysis, we also reveal the dual property of fast reciprocal inhibition to establish in- and anti-phase synchronized bursting.     

Nonequilibrium Keldysh formalism for interacting leads—Application to quantum dot transport driven by spin bias

The conductance through a mesoscopic system of interacting electrons coupled to two adjacent leads is conventionally derived via the Keldysh nonequilibrium Green’s function technique, in the limit of noninteracting leads [Y. Meir, N.S. Wingreen, Phys. Rev. Lett. 68 (1992) 2512]. We extend the standard formalism to cater for a quantum dot system with Coulombic interactions between the quantum dot and the leads. The general current expression is obtained by considering the equation of motion of the time-ordered Green’s function of the system. The nonequilibrium effects of the interacting leads are then incorporated by determining the contour-ordered Green’s function over the Keldysh loop and applying Langreth’s theorem. The dot–lead interactions significantly increase the height of the Kondo peaks in density of states of the quantum dot. This translates into two Kondo peaks in the spin differential conductance when the magnitude of the spin bias equals that of the Zeeman splitting. There also exists a plateau in the charge differential conductance due to the combined effect of spin bias and the Zeeman splitting. The low-bias conductance plateau with sharp edges is also a characteristic of the Kondo effect. The conductance plateau disappears for the case of asymmetric dot–lead interaction.