Effect of the dynamic topology on the performance of PSO-2S algorithm for continuous optimization

International audiencePSO-2S is a multi-swarm PSO algorithm using charged particles in a partitioned search space for continuous optimization problems. In order to improve the performance of PSO-2S, this paper proposes a novel variant of this algorithm, called DPSO-2S, which uses the Dcluster neighborhood topologies to organize the communication networks between the particles. Experiments were conducted on a set of classical benchmark functions. The obtained results prove the effectiveness of the proposed algorithm

A Note on Transfinite M Theory and the Fine Structure Constant

In this short note, using notions from $p$-Adic QFT and $p$-branes, we derive the transfinite M $theoretical$ corrections $(\alpha_M)^{-1} = 100 + 61 \phi$ to El Naschie's inverse fine structure constant value $(\alpha_{HS})^{-1}= 100 + 60\phi$ which was based on a transfinite Heterotic string theory ormalism . $\phi$ is the Golden Mean $0.6180339...$. Our results are consistent with recent Astrophysical observations of he Boomerang and Maxima experiments, with previous results based on the four dimensional gravitational conformal anomaly calculations and with an enhanced hierarchy of the number of lines on Del Pezzo surfaces.Comment: 11 pages,LaTe

Resolvent of Large Random Graphs

We analyze the convergence of the spectrum of large random graphs to the spectrum of a limit infinite graph. We apply these results to graphs converging locally to trees and derive a new formula for the Stieljes transform of the spectral measure of such graphs. We illustrate our results on the uniform regular graphs, Erdos-Renyi graphs and preferential attachment graphs. We sketch examples of application for weighted graphs, bipartite graphs and the uniform spanning tree of n vertices.Comment: 21 pages, 1 figur

Regional increase in the expression of the BCAT proteins in Alzheimer's disease brain: Implications in glutamate toxicity

BACKGROUNDThe human branched chain aminotransferases (hBCATm, mitochondrial and hBCATc, cytosolic) are major contributors to brain glutamate production. This excitatory neurotransmitter is thought to contribute to neurotoxicity in neurodegenerative conditions such as Alzheimer's disease (AD) but the expression of hBCAT in this disease has not previously been investigated.OBJECTIVEThe objective of investigating hBCAT expression is to gain insight into potential metabolic pathways that may be dysregulated in AD brain, which would contribute to glutamate toxicity.METHODSWestern blot analysis and immunohistochemistry were used to determine the expression and localization of hBCAT in postmortem frontal and temporal cortex from AD and matched control brains.RESULTSWestern blot analysis demonstrated a significant regional increase in hBCATc expression in the hippocampus (↑ 36%; p-values of 0.012), with an increase of ↑ 160% reported for hBCATm in the frontal and temporal cortex (p-values = 4.22 × 10-4 and 2.79 × 10-5, respectively) in AD relative to matched controls, with evidence of post-translational modifications to hBCATm, more prominent in AD samples. Using immunohistochemistry, a significant increase in immunopositive labelling of hBCATc was observed in the CA1 and CA4 region of the hippocampus (p-values = 0.011 and 0.026, respectively) correlating with western blot analysis. Moreover, the level of hBCATm in the frontal and temporal cortex correlated significantly with disease severity, as indicated by Braak staging (p-values = 5.63 × 10-6 and 9.29 × 10-5, respectively).CONCLUSIONThe expression of the hBCAT proteins is significantly elevated in AD brain. This may modulate glutamate production and toxicity, and thereby play a role in the pathogenesis of the disease

Cluster J Mycobacteriophages: Intron Splicing in Capsid and Tail Genes

Bacteriophages isolated on Mycobacterium smegmatis mc2155 represent many distinct genomes sharing little or no DNA sequence similarity. The genomes are architecturally mosaic and are replete with genes of unknown function. A new group of genomes sharing substantial nucleotide sequences constitute Cluster J. The six mycobacteriophages forming Cluster J are morphologically members of the Siphoviridae, but have unusually long genomes ranging from 106.3 to 117 kbp. Reconstruction of the capsid by cryo-electron microscopy of mycobacteriophage BAKA reveals an icosahedral structure with a triangulation number of 13. All six phages are temperate and homoimmune, and prophage establishment involves integration into a tRNA-Leu gene not previously identified as a mycobacterial attB site for phage integration. The Cluster J genomes provide two examples of intron splicing within the virion structural genes, one in a major capsid subunit gene, and one in a tail gene. These genomes also contain numerous free-standing HNH homing endonuclease, and comparative analysis reveals how these could contribute to genome mosaicism. The unusual Cluster J genomes provide new insights into phage genome architecture, gene function, capsid structure, gene mobility, intron splicing, and evolution. © 2013 Pope et al

Loss of survivin in intestinal epithelial progenitor cells leads to mitotic catastrophe and breakdown of gut immune homeostasis

A tightly regulated balance of proliferation and cell death of intestinal epithelial cells (IECs) is essential for maintenance of gut homeostasis. Survivin is highly expressed during embryogenesis and in several cancer types, but little is known about its role in adult gut tissue. Here, we show that Survivin is specifically expressed in transit-amplifying cells and Lgr5(+) stem cells. Genetic loss of Survivin in IECs resulted in destruction of intestinal integrity, mucosal inflammation, and death of the animals. Survivin deletion was associated with decreased epithelial proliferation due to defective chromosomal segregation. Moreover, Survivin-deficient animals showed induced phosphorylation of p53 and H2AX and increased levels of cell-intrinsic apoptosis in IECs. Consequently, induced deletion of Survivin in Lgr5(+) stem cells led to cell death. In summary, Survivin is a key regulator of gut tissue integrity by regulating epithelial homeostasis in the stem cell niche

An unusual cause of gastric outlet obstruction during percutaneous endogastric feeding: a case report

<p>Abstract</p> <p>Introduction</p> <p>The differential diagnoses of acute abdomen in children include common and rare pathologies. Within this list, different types of bezoars causing gastrointestinal obstruction have been reported in the literature and different methods of management have been described. The aim of this article is to highlight a rare presentation of lactobezoars following prolonged percutaneous endoscopic gastrostomy feeding and its successful surgical management.</p> <p>Case presentation</p> <p>A 16-year-old boy was admitted to a paediatric ward with abdominal distension and high output from his permanent gastrostomy feeding tube, with drainage of bilious fluids. The clinical, radiological and endoscopical examinations were suggestive of partial duodenal obstruction with multiple bezoars in the stomach and duodenum. Gastrojejunostomy was performed after the removal of 14 bezoars. The child had an uneventful postoperative course and was discharged on the sixth postoperative day in a stable condition.</p> <p>Conclusion</p> <p>Lactobezoars should be included in the differential diagnosis of acute abdominal pain in patients with percutaneous endogastric feeding. Endoscopy is important in making the diagnosis of this surgical condition of the upper gastrointestinal tract in a child.</p