Enacyloxins are products of an unusual hybrid modular polyketide synthase encoded by a cryptic Burkholderia ambifaria Genomic Island

Gram-negative Burkholderia cepacia complex (Bcc) isolates were screened for antimicrobial activity against cystic fibrosis microbial pathogens, and the ability of B.?ambifaria to inhibit B.?multivorans was identified. The activity was mapped to a cluster of cryptic, quorum-sensing-regulated modular polyketide synthase (PKS) genes. Enacyloxin IIa and its stereoisomer designated iso-enacyloxin IIa were identified as metabolic products of the gene cluster, which encoded an unusual hybrid modular PKS consisting of multiple proteins with sequence similarity to cis-acyltransferase (cis-AT) PKSs and a single protein with sequence similarity to trans-AT PKSs. The discovery of the potent activity of enacyloxins against drug-resistant bacteria and the gene cluster that directs their production provides an opportunity for engineered biosynthesis of innovative enacyloxin derivatives and highlights the potential of Bcc bacteria as an underexploited resource for antibiotic discovery.     

Artificial neural network for discrete model order reduction with substructure preservation

This paper presents a new technique for model order reduction (MOR) that is based on an artificial neural network (ANN) prediction. The ANN-based MOR can be applied for different scale systems with substructure preservation. In the proposed technique, the ANN is implemented for predicting the unknown elements of the reduced order model. Prediction of the ANN architecture is based on minimizing the cost function obtained by the difference between the actual and desired system behaviour. The ANN prediction process is pursued while maintaining the full order substructure in the reduced model. The proposed ANN-based model order reduction method is compared to recently published work on MOR techniques. Simulation results verify the validity of the new MOR technique.     

Fully Depletion of Advanced Silicon on Insulator MOSFETs

Scaling of the transistor has been tremendous successful in the beginning with reduction of the gate oxide thickness and increase of doping concentration. Moving into smaller dimension, those are not enough to overcome the short channel effect. Starting with changing in materials and followed by device architecture is needed which require fully depletion operation. This article reviews the fully-depletion operation of thin body of silicon on insulator of advanced MOSFETs.     

Thermodynamic Effects on Grade Transition of Polyethylene Polymerization in Fluidized Bed Reactors

An off‐line dynamic optimization procedure is employed to optimize the transition between different grades of linear low density polyethylene in a fluidized bed reactor. This type of reactor is frequently operated under condensed mode, which consists of injecting induced condensing agents (ICA) to absorb part of the reaction heat. However, the presence of ICA affects the solubility of monomers in the polymer, so it is important to account for this effect in a grade transition optimization strategy. A kinetic model is combined with a thermodynamic model based on the Sanchez–Lacombe equation of state to describe the grade transitions. Simplified correlations are then suggested to predict the impact of ICA on ethylene and comonomer solubility in a quaternary system. The results highlight the importance of the thermodynamic model during grade transition.     

Study of Optical Soliton Perturbation with Quadratic-Cubic Nonlinearity by Lie Symmetry and Group Invariance

Here, optical soliton perturbation with quadratic-cubic nonlinearity has been discussed by applying Lie symmetry and group invariants. The perturbation terms include third and fourth order dispersions in addition to self-steepening, intermodal dispersion and higher order dispersion effects. Using presented algorithms, Bright and dark soliton solutions are revealed.     

(Ba<Subscript>0.93</Subscript>Nd<Subscript>0.07</Subscript>)TiO<Subscript>3</Subscript> thin films prepared by sol–gel method as a potential dielectric resonator antenna application

In this paper, we report the application of Neodymium (Nd) doped barium titanate thin films (Ba_1-xNd_x) TiO₃ with x = 0 and 0.07 as dielectric resonator antenna. The films were prepared using the sol–gel method and dip-coating technique. Barium acetate, titanium (IV) isopropoxide and neodymium (III) acetate hydrate were used as precursors while glacial acetic acid and acetylacetone were used as solvents. Si wafers were used as a substrate with dipping times varying from 10, 30, and 50 s. The 0.07 films were >800 nm thick and crystallized after being annealed at 800°C for 30 min. The films were tested as dielectric resonator antenna. It was found that, on the actual antenna circuit, the resonant frequency decreased as the (Ba_0.93Nd_0.07) TiO₃ films thickness increased (from 0.8379, to 5.4525 μm). All samples resonate in the range of 8.68–8.83 GHz with quasi omni-directional radiation patterns.