Charge delocalization characteristics of regioregular high mobility polymers.

Controlling the regioregularity among the structural units of narrow bandgap conjugated polymer backbones has led to improvements in optoelectronic properties, for example in the mobilities observed in field effect transistor devices. To investigate how the regioregularity affects quantities relevant to hole transport, regioregular and regiorandom oligomers representative of polymeric structures were studied using density functional theory. Several structural and electronic characteristics of the oligomers were compared, including chain planarity, cation spin density, excess charges on molecular units and internal reorganizational energy. The main difference between the regioregular and regiorandom oligomers is found to be the conjugated backbone planarity, while the reorganizational energies calculated are quite similar across the molecular family. This work constitutes the first step on understanding the complex interplay of atomistic changes and an oligomer backbone structure toward modeling the charge transport properties

First record of Sphaeralcea bonariensis (Cav.) Griseb. (Malvaceae) as a casual alien species in the Mediterranean area

Sphaeralcea bonariensis (Cav.) Griseb. is here reported for the first time as alien species in Italy and in the Mediterranean area. It is a perennial shrub native to Southern America, where it is often considered a ruderal species frequent in cultivated areas. It was found in a population of a few individuals within Opuntia ficus-indica groves of Rocca Palumba territory (Western Sicily). Actually, due to short-term observational period and the low number of plants, Sphaeralcea bonariensis should be considered as a casual species in Italy. The ecological characteristics of the growing stand and the consistency of the population, as well as the possible causes of its introduction, are briefly discussed

From Design to Production Control Through the Integration of Engineering Data Management and Workflow Management Systems

At a time when many companies are under pressure to reduce "times-to-market" the management of product information from the early stages of design through assembly to manufacture and production has become increasingly important. Similarly in the construction of high energy physics devices the collection of (often evolving) engineering data is central to the subsequent physics analysis. Traditionally in industry design engineers have employed Engineering Data Management Systems (also called Product Data Management Systems) to coordinate and control access to documented versions of product designs. However, these systems provide control only at the collaborative design level and are seldom used beyond design. Workflow management systems, on the other hand, are employed in industry to coordinate and support the more complex and repeatable work processes of the production environment. Commercial workflow products cannot support the highly dynamic activities found both in the design stages of product development and in rapidly evolving workflow definitions. The integration of Product Data Management with Workflow Management can provide support for product development from initial CAD/CAM collaborative design through to the support and optimisation of production workflow activities. This paper investigates this integration and proposes a philosophy for the support of product data throughout the full development and production lifecycle and demonstrates its usefulness in the construction of CMS detectors.Comment: 18 pages, 13 figure

COX-2 in the neurodegenerative process of Parkinson's disease

Copyright © 2012 International Union of Biochemistry and Molecular Biology, Inc.Peer reviewedPublisher PD

Uses and Knowledge of Plant Species by Mongolian Herders in the Gobi Desert and Identification of Species of Interest for Planting

In Central Asia, many projects propose to establish single-species saxaul (Haloxylon ammodendron (C.A. Meyer) Bunge) plantations. An ethnobotanical survey was carried out among herders in Ulaanbadrakh, in the Dornogobi province, and herders in Gurvansaikhan, in the Dundgobi province in the Gobi Desert (Mongolia). The aim of this survey is to verify the interest of saxaul for the local populations, and to identify other woody species of interest for planting. Herders were questioned about the use of plant species from the Gobi grazing lands: livestock feed, human food, and then about plant species non-eaten by livestock and those that could be toxic to them. A total of 75 species and 413 uses related to these species were cited. We retained the species cited by at least 25% of the herders: 8 species of interest were selected, then sorted according to the number of associated positive uses, while focusing on the species cited in Ulaanbadrakh (area of interest in the Dornogobi). Saxaul appears to be the most numerous woody species for the herders and their livestock. Three other woody species of interest have also been identified. These results show that there is a high diversity of plant species used. It would be interesting to investigate the interest of a multi-species plantation for herders and their livestock in future surveys

ENVIRONMENTAL QUALITY OF SOFT-BOTTOM IN HAIFA BAY (ISRAEL): AMPHIPOD ASSEMBLAGES

Ecological information concerning amphipods and representation of their spatial distribution through GIS provides an estimate of local environmental quality

α,ω-Dithiol Oligo(phenylene vinylene)s for the Preparation of High-Quality π-Conjugated Self-Assembled Monolayers and Nanoparticle-Functionalized Electrodes

While thioacetate-terminated oligo(phenylene vinylene)s (OPVs) have been synthesized and employed in applications involving the formation of metal–molecule–metal junctions, the synthesis and application of potentially more versatile α,ω-dithiol OPVs have not previously been described. Here, a thiomethyl-precursor route to the synthesis of α,ω-dithiol OPVs is reported and their ability to form well-ordered self-assembled monolayers (SAMs) without the addition of exogenous deprotection reagents is described. α,ω-Dithiol OPV monolayers exhibit thicknesses consistent with molecular length and are nearly defect-free, as assayed by electrochemical measurements. To demonstrate the ease with which SAMs containing these bifunctional OPVs can, in contrast to thioacetate functionalized OPVs, be further functionalized with materials other than gold, we have modified them in a single step with a sub-monolayer of cadmium selenide nanocrystals (NCs). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) confirm that these NC-modified films are both smooth and uniform over the largest areas investigated (\u3e 10 μm2) and no evidence of NC aggregation is observed. To evaluate the electrochemical response of these metal–molecule– semiconductor assemblies we have fabricated NC-modified OPV SAMs with ferrocene-coated NCs. Variable-frequency alternating current voltammetry indicates that electron transfer in these assemblies is much more rapid than in analogous structures formed using simple alkane dithiols. It thus appears that α,ω-dithiol OPVs are well suited for the formation of high-quality conducting SAMs for the functionalization of gold and other surfaces