Extracellular Polymeric Substances (EPS) from Aerobic Granular Sludges: Extraction,Fractionation, and Anionic Properties

A multi-method protocol previously proposed for the extraction of extracellular polymeric substances (EPS) from flocculated sludges was investigated on dense aerobic granules. The protocol combines mechanical disruption by sonication and chemical extraction using the Tween detergent and the cation chelator, EDTA. Polysaccharides were mainly recovered during the first sonication step while proteins were recovered all along the extractive procedure with a high prevalence in the EDTA step. These data confirmed the interest of the multi-method protocol for harvesting a diversified pool of EPS from dense granules and for fractionation of the polymers according to their physicochemical properties. In addition, the high extractability of proteins with EDTA confers a specific behavior of the aerobic granules towards the multi-method extraction protocol, supporting the idea that proteins are associated in the granule matrix through ionic interactions involving divalent cations. Analysis of the extracted EPS by anionic exchange chromatography confirmed the presence of highly anionic proteins that were specifically detected in the extracts obtained from granules. One important question is now to investigate whether these highly anionic proteins are involved in the aggregation and densification process and if their presence is related to the cohesive properties of these particles.     

A Novel Parameter Identification Approach for C–V–T Characteristics of Multi-Quantum Wells Schottky Diode Using Ant Lion Optimizer

Russian Microelectronics - We report the capacitance-voltage (C–V) characteristics of multi quantum wells Schottky diode. This diode is based on Aluminum gallium arsenide, which is highly...     

The specification of the temporal behaviour for multimedia scheduling

In this paper, we present a timing model for describing the temporal behaviour of a multimedia application. This timing model is based on the so called temporal profiles. After illustrating such a notion through examples, we specify formally temporal profiles and the scheduling problem through a relation between temporal profiles.     

Adapting contention-based forwarding to urban vehicular topologies for active safety applications

Contention-based forwarding (CBF) is a broadcasting technique used to disseminate emergency messages for traffic safety applications in intelligent transportation systems. Its design hypotheses have however been based on three major assumptions: uniform vehicular topology, nonfading channels and homogeneous communication capabilities. Realistic vehicular urban topologies do not comply with any of them, making CBF select relays, which may not exist, may not be reached or may not be optimal due to heterogeneous transmit capabilities. In this paper, we propose to adapt CBF to such challenging environment by first employing two different mechanisms as a function of the topology and second by considering the dissemination capabilities of the relays, allowing for example road-side units or tall vehicles to preferably act as relays when necessary. Our protocol, called Bi-Zone Broadcast, is evaluated in a realistic urban environment and showed to provide around 46 % improvement in dissemination delay and 40 % reduction in overhead compared to plain CBF or flooding. We finally shed light to other aspects of CBF that remain unsolved and should be addressed in future work to further improve the reliability of dissemination protocols for traffic safety protocols.     

Finite-dimensional right ideals in some algebras associated with a locally compact group

Let be a discrete group, a commutative discrete cancellative semigroup or a locally compact abelian group. Let be the space of bounded, uniformly continuous, complex-valued functions on With an Arens-type product, the conjugate becomes a Banach algebra. We prove, that unlike left ideals, finite-dimensional right ideals exist in if and only if is compact.

     

Design and Calibration of a Large Open-Ended Coaxial Probe for the Measurement of the Dielectric Properties of Concrete

The subject of this paper is the design and calibration of an open-ended coaxial probe for the nondestructive measurement of the dielectric properties of concrete. Measurements are made between 100-900 MHz, frequencies which are often used in geophysics and civil engineering for ground penetrating radar inspection. The probe is calibrated using measurements on saline solutions in conjunction with three different mathematical techniques for comparative study. Measurements of mortar and concrete specimens having different water/cement ratios were made in order to observe the standard deviations due to their heterogeneous nature. Similar to the case of relatively homogeneous rock specimens (limestone and granite), the standard deviation for heterogeneous concrete samples do not exceed 5%. In addition, the effect of the concrete's porosity on its dielectric properties was clearly observed: measured permittivity between 4-4.5 at 900 MHz for porous concrete, and between 6.5-7.5 at 900 MHz for dense concrete.     

Right Cancellation in the LUC-Compactification of a Locally Compact Group

Write G^* = G^LUC\G where G^LUC is the largest semigroup compactificationof the locally compact group G. Then the set of points of G^*which are right cancellable in G^* = G^LUC is large; in fact ithas an interior in G^* which is dense in G^*. Corollaries aregiven about the number of left ideals in G^* = G^LUC and the sizeof right ideals in the algebra LUC(G)^*.     

Multi-radio multi-channel routing metrics in IEEE 802.11s based wireless mesh networks

IEEE 802.11s is one of the emerging standards designed to build wireless mesh networks which may serve to extend the coverage of access networks. The default IEEE 802.11s path selection protocol Hybrid Wireless Mesh Protocol (HWMP) is based on the radio-aware airtime link metric (ALM) that outperforms the hop-count metric in single channel multi-hop wireless networks. However, this metric may lead to capacity degradation when multiple channels and/or multi-radio are used. To fully exploit the capacity gain of multiple channels use, new routing metrics have been proposed such as weighted cumulative expected transmission time, metric of interference and channel switching, interference aware routing metric, exclusive expected transmission time, and normalized bottleneck link capacity. These metrics distribute the data traffic load among channels and/or radios to reach the final destination. In this paper, we provide a qualitative comparison study that considers the characteristics of these metrics. Indeed, we substitute ALM by these different metrics, and we evaluate the performance of HWMP through simulation. Obtained results allow us to identify the appropriate use case of each metric.     

Tuning the hydrophilicity of gold nanoparticles templated in star block copolymers

We report on a simple procedure to tune the hydrophilicity of hybrid gold nanoparticles. The nanoparticles have been prepared in the core of a poly(ethylene glycol)-block-poly(epsilon-caprolactone) (PEG-b-PCL) five-arm star block copolymer. A hydrophilic corona was then added to these hybrid gold nanoparticles by direct chemisorption of trithiocarbonate-containing poly(acrylic acid) chains. These polymers were synthesized by RAFT polymerization with a trithiocarbonate as the chain-transfer agent. The efficiency of the grafting was evidenced by TEM, AFM, and DLS and by the successful transfer of these nanoparticles from organic solvent to water.