Modelling of Grey Wolf Optimization Algorithm Using 2D P Colonies

In this paper, we investigate a possibility of Grey wolf optimization algo- rithm simulation by 2D P colonies. We introduce a new kind of 2D P colony equipped with a blackboard. It is used by agents to store information that is reachable by all the agents from every place in the environment

Growth Rate Evaluation of the Alcyonacean Soft Coral Sinularia polydactyla (Ehrenberg, 1834) at Hurghada, Northern Red Sea, Egypt

Growth rate of Sinularia polydactyla has been studied to determine the changes of surface area using 2D method as modified method for measuring growth increasing. The measurements indicate to that restricted and slow growth rates in the big samples under the variable oceanographic conditions. Summer recorded the highest rates of growth. The mean growth rate of the biggest colonies recorded 51.83±4.90mm2 while the small colonies recorded 20.8±6.25 mm2 in summer. On contrary, autumn showed the lowest and restricted rates during. The annual growth reached 116.28±10.57 and 33.78±12.45mm2/y in the big and small colonies respectively. The growth ratio in relation to the original colonies size appears to grow with a relatively faster ratio in the small colonies (9.73±1.62% with a range of 6.67-12.68%) than the elder one (5.79±0.34% with a range of 4.37-6.72%). The temperature changes, gonads and gametes maturation, sedimentation rates are major controlling factors affect the growth rates. ANOVA Bivariate correlation illustrated a positive relationship (without significant difference) between the growth and temperature (ºC) (at P=0.38 and R2=0.62). By comparing the present study and the available growth data of Sinularia sp., we found that, the annual growth of S. polydactyla is higher (116.28±10.57 - 33.78±12.45mm2/yr) than the previous studies. Keywords: Growth Rate Sinularia polydactyla, Hurghada, Red Se

Studies of Bacterial Branching Growth using Reaction-Diffusion Models for Colonial Development

Various bacterial strains exhibit colonial branching patterns during growth on poor substrates. These patterns reflect bacterial cooperative self-organization and cybernetic processes of communication, regulation and control employed during colonial development. One method of modeling is the continuous, or coupled reaction-diffusion approach, in which continuous time evolution equations describe the bacterial density and the concentration of the relevant chemical fields. In the context of branching growth, this idea has been pursued by a number of groups. We present an additional model which includes a lubrication fluid excreted by the bacteria. We also add fields of chemotactic agents to the other models. We then present a critique of this whole enterprise with focus on the models' potential for revealing new biological features.Comment: 1 latex file, 40 gif/jpeg files (compressed into tar-gzip). Physica A, in pres

DNA polymerase α (swi7) and the flap endonuclease fen1 (rad2) act together in the s-phase alkylation damage response in S. pombe

Polymerase α is an essential enzyme mainly mediating Okazaki fragment synthesis during lagging strand replication. A specific point mutation in Schizosaccharomyces pombe polymerase α named swi7-1, abolishes imprinting required for mating-type switching. Here we investigate whether this mutation confers any genome-wide defects. We show that the swi7-1 mutation renders cells hypersensitive to the DNA damaging agents methyl methansulfonate (MMS), hydroxyurea (HU) and UV and incapacitates activation of the intra-S checkpoint in response to DNA damage. In addition we show that, in the swi7-1 background, cells are characterized by an elevated level of repair foci and recombination, indicative of increased genetic instability. Furthermore, we detect novel Swi1-, -Swi3- and Pol α- dependent alkylation damage repair intermediates with mobility on 2D-gel that suggests presence of single-stranded regions. Genetic interaction studies showed that the flap endonuclease Fen1 works in the same pathway as Pol α in terms of alkylation damage response. Fen1 was also required for formation of alkylation- damage specific repair intermediates. We propose a model to explain how Pol α, Swi1, Swi3 and Fen1 might act together to detect and repair alkylation damage during S-phase

Local Decoders for the 2D and 4D Toric Code

We analyze the performance of decoders for the 2D and 4D toric code which are local by construction. The 2D decoder is a cellular automaton decoder formulated by Harrington which explicitly has a finite speed of communication and computation. For a model of independent $X$ and $Z$ errors and faulty syndrome measurements with identical probability we report a threshold of $0.133\%$ for this Harrington decoder. We implement a decoder for the 4D toric code which is based on a decoder by Hastings arXiv:1312.2546 . Incorporating a method for handling faulty syndromes we estimate a threshold of $1.59\%$ for the same noise model as in the 2D case. We compare the performance of this decoder with a decoder based on a 4D version of Toom's cellular automaton rule as well as the decoding method suggested by Dennis et al. arXiv:quant-ph/0110143 .Comment: 22 pages, 21 figures; fixed typos, updated Figures 6,7,8,

The water clock of Proteus mirabilis paces colony periodic and synchronous swarming

For decades, the origin of the concentric ring pattern of bacterial swarming colonies has puzzled microbiologists. Thanks to _in situ_ and real time infrared microspectroscopy and the brilliance of the infrared beam at SOLEIL synchrotron, we demonstrate here that _Proteus mirabilis_ swarming is paced by a periodic variation of the water activity at colony's edge. This periodic variation originates a phase transition within the extracellular matrix water H bond network which switches on and off the exopolysaccharides viscoelasticity and, consequently, the ability of bacterial cells to swarm. A dynamic behaviour emerges from the global properties of the multicellular entity which here relies on the ability of the bacterial cells to tune exoproducts synthesis in order to undergo sharp transitions above/below a given water activity threshold